CN114703404B - Aluminum foil material for low-density pinhole current collector of new energy lithium battery and preparation method of aluminum foil material - Google Patents
Aluminum foil material for low-density pinhole current collector of new energy lithium battery and preparation method of aluminum foil material Download PDFInfo
- Publication number
- CN114703404B CN114703404B CN202210201104.3A CN202210201104A CN114703404B CN 114703404 B CN114703404 B CN 114703404B CN 202210201104 A CN202210201104 A CN 202210201104A CN 114703404 B CN114703404 B CN 114703404B
- Authority
- CN
- China
- Prior art keywords
- controlled
- rolling
- aluminum
- refining
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 134
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 127
- 239000011888 foil Substances 0.000 title claims abstract description 73
- 239000000463 material Substances 0.000 title claims abstract description 67
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims abstract description 41
- 229910052744 lithium Inorganic materials 0.000 title claims abstract description 41
- 238000002360 preparation method Methods 0.000 title claims abstract description 11
- 238000007670 refining Methods 0.000 claims abstract description 66
- 238000000034 method Methods 0.000 claims abstract description 53
- 238000005096 rolling process Methods 0.000 claims abstract description 53
- 238000003723 Smelting Methods 0.000 claims abstract description 52
- 238000010438 heat treatment Methods 0.000 claims abstract description 40
- 238000001914 filtration Methods 0.000 claims abstract description 33
- 238000005097 cold rolling Methods 0.000 claims abstract description 21
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 102
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 74
- 239000007789 gas Substances 0.000 claims description 52
- 229910052757 nitrogen Inorganic materials 0.000 claims description 51
- 229910052786 argon Inorganic materials 0.000 claims description 37
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 35
- 239000000047 product Substances 0.000 claims description 32
- 239000003921 oil Substances 0.000 claims description 24
- 239000010731 rolling oil Substances 0.000 claims description 24
- 239000002245 particle Substances 0.000 claims description 23
- 238000000137 annealing Methods 0.000 claims description 18
- 239000011265 semifinished product Substances 0.000 claims description 18
- 229910000831 Steel Inorganic materials 0.000 claims description 16
- 238000001816 cooling Methods 0.000 claims description 16
- 239000007788 liquid Substances 0.000 claims description 16
- 239000010959 steel Substances 0.000 claims description 16
- 239000003795 chemical substances by application Substances 0.000 claims description 15
- 238000001035 drying Methods 0.000 claims description 14
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 9
- 238000007664 blowing Methods 0.000 claims description 9
- 238000005266 casting Methods 0.000 claims description 9
- 229910017604 nitric acid Inorganic materials 0.000 claims description 9
- 239000000843 powder Substances 0.000 claims description 9
- 239000002253 acid Substances 0.000 claims description 8
- 239000000654 additive Substances 0.000 claims description 8
- 230000000996 additive effect Effects 0.000 claims description 8
- 238000004458 analytical method Methods 0.000 claims description 8
- 238000007599 discharging Methods 0.000 claims description 8
- 238000003466 welding Methods 0.000 claims description 8
- 239000008367 deionised water Substances 0.000 claims description 7
- 229910021641 deionized water Inorganic materials 0.000 claims description 7
- 230000000007 visual effect Effects 0.000 claims description 7
- 239000002994 raw material Substances 0.000 claims description 5
- 238000004321 preservation Methods 0.000 claims description 4
- 238000004140 cleaning Methods 0.000 claims description 2
- 238000005516 engineering process Methods 0.000 abstract description 42
- 229910045601 alloy Inorganic materials 0.000 abstract description 22
- 239000000956 alloy Substances 0.000 abstract description 22
- 238000004519 manufacturing process Methods 0.000 abstract description 11
- 239000002131 composite material Substances 0.000 abstract description 9
- 238000005098 hot rolling Methods 0.000 abstract description 7
- 238000005265 energy consumption Methods 0.000 abstract description 6
- 229910052799 carbon Inorganic materials 0.000 abstract description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 4
- 238000005275 alloying Methods 0.000 abstract description 2
- 238000013329 compounding Methods 0.000 abstract description 2
- 230000007613 environmental effect Effects 0.000 abstract description 2
- 238000005457 optimization Methods 0.000 abstract description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 50
- 239000000243 solution Substances 0.000 description 14
- 229910052742 iron Inorganic materials 0.000 description 9
- 150000001875 compounds Chemical class 0.000 description 6
- 238000007689 inspection Methods 0.000 description 6
- 230000001590 oxidative effect Effects 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 4
- 238000009413 insulation Methods 0.000 description 3
- 238000004806 packaging method and process Methods 0.000 description 3
- 229910000838 Al alloy Inorganic materials 0.000 description 2
- 229910000905 alloy phase Inorganic materials 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 239000012467 final product Substances 0.000 description 2
- 239000008267 milk Substances 0.000 description 2
- 210000004080 milk Anatomy 0.000 description 2
- 235000013336 milk Nutrition 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 229910018191 Al—Fe—Si Inorganic materials 0.000 description 1
- 241001391944 Commicarpus scandens Species 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910016583 MnAl Inorganic materials 0.000 description 1
- 238000004026 adhesive bonding Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000019771 cognition Effects 0.000 description 1
- 238000007872 degassing Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 238000000265 homogenisation Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C21/00—Alloys based on aluminium
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/40—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling foils which present special problems, e.g. because of thinness
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B3/00—Rolling materials of special alloys so far as the composition of the alloy requires or permits special rolling methods or sequences ; Rolling of aluminium, copper, zinc or other non-ferrous metals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/06—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
- C22C1/026—Alloys based on aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/04—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B3/00—Rolling materials of special alloys so far as the composition of the alloy requires or permits special rolling methods or sequences ; Rolling of aluminium, copper, zinc or other non-ferrous metals
- B21B2003/001—Aluminium or its alloys
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Metal Rolling (AREA)
- Cell Electrode Carriers And Collectors (AREA)
Abstract
The invention belongs to the field of aluminum material manufacturing, and relates to an aluminum foil material for a low-density pinhole anode current collector of a new energy lithium battery and a preparation method thereof, wherein the method comprises the following steps: preparing alloy components; fe element pretreatment technology; compounding a multi-step refining technology by a smelting furnace; an online multistage composite filtering technology; a heat treatment technique; cold rolling; foil rolling. Compared with the prior art, the aluminum foil material for the positive electrode current collector is produced by using a green short-flow method, and has the characteristics of excellent mechanical property, low-density pinholes and the like through alloying treatment, element pretreatment technology, composite refining technology, online filtering technology and processing technology optimization. In the aspect of environmental protection, the process technology belongs to a green manufacturing technology, and compared with the traditional hot rolling technology, the energy consumption and carbon emission are reduced by more than 30%, so that the process technology has a wide application market.
Description
Technical Field
The invention belongs to the field of aluminum material manufacturing, and relates to an aluminum foil material for a low-density pinhole current collector of a new energy lithium battery and a preparation method thereof.
Background
Along with the deeper and deeper cognition of people on the environment-friendly concept, the new energy lithium battery car has the trip advantages of low carbon and environment protection and becomes the first choice of people. In recent years, the occupancy of new energy lithium battery automobiles rises year by year, and the market demand is expanding along with the fact that the aluminum foil material of the positive electrode current collector of the lithium battery is used as a key material of the new energy lithium battery. Along with the continuous expansion of the endurance mileage, the energy density of the lithium battery is higher and higher, so that the surface density requirement on the aluminum foil material of the positive current collector of the lithium battery is higher and higher, the thickness of the aluminum foil material of the positive current collector of the lithium battery is expected to be further thinned, the thickness is thinned from 15 mu m to below 8-10 mu m, and the thinning degree is 33% -46%; the number of pinholes can reach 50 per square meter after the current technical means is thinned, but the requirement of obtaining pinholes on the thinned lithium battery anode current collector aluminum foil material is contrary to the requirement that high-density pinholes are not allowed to occur at the same time for downstream clients. Along with the thickness reduction of the aluminum foil material of the positive current collector of the lithium battery, pinholes are a necessary phenomenon, but how to control the aluminum foil material of the positive current collector of the lithium battery to avoid high-density pinholes, and the preparation process of the aluminum foil material of the positive current collector of the lithium battery needs to be optimized. The prior art CN 110423920A is mainly aimed at improving the process of a soft package foil product with the thickness of 6.5 mu m, so as to meet the packaging tightness requirement of the soft package foil product in the service process; the CN 111519050A improves the processing process of the 15 mu m product of the electronic tag foil, and solves the problems of rolling dark lines, tissue stripes, easy belt breakage and the like in the aluminum foil production process; CN 112921213A solves the problem that the number of pinholes per square meter of aluminum foil for packaging milk is less than 300, the pinhole aperture is less than 0.1mm, and the glue leakage is avoided when downstream milk packaging clients are placed for gluing and compounding. The three prior arts do not relate to the management and control of the low density pinholes in the thickness range of 8-10 mu m of the aluminum foil material of the positive current collector of the lithium battery and the service characteristics of the lithium battery, and meanwhile, the production modes of the three prior arts all adopt the traditional hot rolling technology, so that the defects of high energy consumption, high pollution and the like are overcome, and the development direction of the double-carbon policy advocated by the state is not met. Therefore, a special technology for lithium battery anode current collector aluminum foil material capable of meeting the low-density pinholes of the thickness range of 8-10 μm and the service characteristics of lithium batteries is needed to meet the development requirements of future new energy lithium batteries.
Disclosure of Invention
In order to overcome the defects, the aluminum foil material for the low-density pinhole current collector of the lithium battery and the preparation method thereof are produced by using a green short-flow casting and rolling method, and the aluminum foil material for the low-density pinhole current collector of the lithium battery can meet the low-density pinhole with the thickness of 8-10 mu m and the service characteristic of the lithium battery by optimizing the micro-alloying optimization proportion, the online aluminum melt quality treatment and filtering technology and the heat treatment process in the cold rolling process, and meanwhile, the aluminum foil material for the positive current collector of the lithium battery has excellent mechanical properties, is convenient to roll and not easy to break after the positive material is coated later, has the Vickers hardness of 50-60Hv, the tensile strength of 260-280Mpa, the elongation percentage of more than or equal to 3.0 percent, and the number of pinholes of less than or equal to 10 per square meter. The excellent mechanical property can improve the subsequent processing property of the aluminum foil material of the positive current collector of the lithium battery, and meanwhile, the thickness is greatly thinned, so that the energy density of the new energy lithium battery can be improved, and the cruising ability of the new energy automobile is improved. The invention adopts the cast rolling-cold rolling process flow to replace the conventional hot rolling-cold rolling process flow, has the advantages of short flow and low production cost, and has good application prospect.
In order to achieve the aim of the invention, the invention adopts the following technical scheme:
the aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery is prepared from the following raw materials in percentage by mass: 0.4-0.55% of Fe, 0.05-0.1% of Si, 0.01-0.02% of Ti, 0.35-0.45% of Mn and the balance of aluminum; (Fe content-Si content): mn content = 1:1.
The invention also provides a preparation method of the aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery, which is characterized by comprising the following steps: according to the raw materials proportioning of claim 1, adding Fe element pretreated by dilute nitric acid and cleaned and dried at the bottom of a smelting furnace; after molten aluminum is 2/3 flattened, adding Si element and Mn element into a smelting furnace, synchronously adding a covering agent, and introducing mixed gas of nitrogen and argon to perform powder blowing refining; introducing molten aluminum into a filter box, performing tertiary filtration, and performing cast rolling through a casting and rolling machine to obtain cast-rolled coil blanks; the cast-rolled coil blank is rolled for 2 passes and then subjected to heat treatment. Welding an outer ring, tightening a steel belt on the surface of the steel belt, and carrying out homogenizing annealing in a high-temperature annealing furnace to obtain a semi-finished product of the aluminum coil; and (3) rolling the obtained semi-finished product to the thickness of a finished product after cold rolling and foil rolling.
Further, the pretreatment steps of Fe element are as follows: and (3) putting Fe element into 0.1-0.15% dilute nitric acid solution to dissolve for 20-30min, then transferring into deionized water to clean for 1-2h, putting into a drying box to remove water, introducing 99.5-99.7% nitrogen protection gas into the drying box, keeping the temperature of furnace gas at 100-110 ℃ for 3-5h.
Further, the refining step is as follows: adding a refining agent according to the proportion of 1.5-2.0kg/t of aluminum water, and simultaneously introducing mixed gas of nitrogen and argon to perform powder blowing refining, wherein the refining is controlled according to 30min, and the refining is divided into 3 stages; the first stage, 0-10min, the refining route in the smelting furnace walks according to the W-shaped route; a second stage, 10-20min, wherein the refining route in the smelting furnace walks according to a 'type' route; a third stage, 20-30min, wherein a refining route in the smelting furnace walks according to a 'loop' route; after the operation is completed, nitrogen is introduced into the smelting furnace, the positive pressure in the furnace is maintained, and the furnace is kept still for 1h. And (5) carrying out a furnace reversing procedure after the scum is not seen on the surface of the visual aluminum liquid.
Further, in the three-stage filtration, the mesh number of the first-stage filter plate is 30PPi, the temperature in the heat preservation box is controlled to be 720-725 ℃, and argon is introduced into the filter box; the mesh number of the second-stage filtering plate is 50PPi, the temperature in the incubator is controlled at 714-719 ℃, and mixed gas of nitrogen and argon is introduced into the filtering box; the mesh number of the third-stage filter plate is 70PPi, the temperature in the incubator is controlled at 705-710 ℃, and nitrogen is introduced into the filter tank.
Further, the homogenizing annealing process comprises the following steps: and (5) preserving heat for 10 hours at the temperature of 380 ℃ of the furnace gas. And then heating to the target heating temperature of 430-480 ℃ according to 3-5 ℃/min, preserving heat for 3-5h after reaching the target heating temperature, cooling the furnace gas according to 5-8 ℃/min, and immediately discharging the furnace and then cooling by air when the furnace gas temperature reaches 280 ℃ to obtain the semi-finished product of the aluminum coil.
Further, the convexity of a working roll of the cold rolling mill is controlled to be 0.02-0.04mm, the roughness Ra value is controlled to be 0.2-0.3 mu m, the online plate shape is controlled to be 7-10I during rolling, the oil temperature is controlled to be 38-43 ℃, the oil nozzle flow is controlled to be 48-55%, and the oil acid value is controlled to be 0.1-0.25mgKOH/g. Wherein the ash content of the rolling oil is controlled to be 5-8g/L.
Further, in the foil rolling process, the rolling oil additive is controlled to be 5-15%, the on-line plate type is controlled to be 3-5I, and the temperature of the rolling oil is controlled to be 40-50 ℃.
Further, carrying out metallographic analysis on the homogenized coiled material, wherein the size of second phase particles is controlled to be 1-5 mu m, and the second phase particles are uniformly distributed; wherein the particles with the size of 1-3 μm account for more than 80%.
Further, the volume ratio of argon to nitrogen in the mixed gas of nitrogen and argon is 1:1.
The preparation method of the aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery comprises the following steps:
(1) Preparing alloy components: according to (Fe content-Si content, i.e. mass of elemental iron minus mass of elemental silicon): mn content=1:1 (mass percent below), fe content 0.4-0.55%, si content 0.05-0.1%, ti content 0.01-0.02%, mn content 0.35-0.45%, and balance aluminum, wherein the sum of Fe, si, ti, mn and Al weight percent is 100%. And (5) performing alloy element proportioning.
(2) Fe element pretreatment technology: the alloy in the step (1) is proportioned according to the proportion, the pretreated Fe element is added at the bottom of the smelting furnace, the pretreatment process is that the Fe element is put into 0.1-0.15% dilute nitric acid solution to be dissolved for 20-30min, then the solution is put into deionized water to be washed for 1-2h, the solution is put into a drying box to remove water, 99.5-99.7% nitrogen protection gas is introduced into the drying box, the furnace gas temperature is 100-110 ℃, and the temperature is kept for 3-5h.
(3) A smelting furnace compound multi-step refining technology: after the aluminum water is flattened by 2/3, adding Si element and Mn element into the smelting furnace, and synchronously adding 2-3kg/t of covering agent of the aluminum water to prevent the aluminum liquid from further oxidizing and slagging. And (3) adding a covering agent, then carrying out refining process for 2-4 hours, adding the refining agent according to the proportion of 1.5-2.0kg/t aluminum water, and simultaneously introducing mixed gas of nitrogen and argon (volume ratio, argon: nitrogen=1:1) to carry out powder blowing refining, wherein the refining is controlled according to 30 minutes, and the total steps are divided into 3 stages. The first stage, 0-10min, the refining route in the smelting furnace walks according to the W-shaped route; a second stage, 10-20min, wherein the refining route in the smelting furnace walks according to a 'type' route; a third stage, 20-30min, wherein a refining route in the smelting furnace walks according to a 'loop' route; after the operation is completed, nitrogen is introduced into the smelting furnace, the positive pressure in the furnace is maintained, and the furnace is kept still for 1h. And (5) carrying out a furnace reversing procedure after the scum is not seen on the surface of the visual aluminum liquid.
(4) On-line multistage composite filtration technology: introducing the aluminum water treated in the step (3) into a filter box, wherein the filter box adopts a three-stage filtering process, the mesh number of a first-stage filter plate is 30PPi, the temperature in the heat preservation box is controlled at 720-725 ℃, and argon is introduced into the filter box; the mesh number of the second-stage filtering plate is 50PPi, the temperature in the incubator is controlled at 714-719 ℃, and mixed gas of nitrogen and argon (volume ratio, argon: nitrogen=1:1) is introduced into the filtering box; the mesh number of the third-stage filter plate is 70PPi, the temperature in the incubator is controlled at 705-710 ℃, and nitrogen is introduced into the filter tank; and then the molten aluminum passes through a casting and rolling machine to obtain cast-rolled coil blanks with the thickness of 6.8 mm.
(5) Heat treatment technology: and (3) rolling the cast-rolled coil obtained in the step (4) for 2 passes, and then performing heat treatment. Welding an outer ring, tightening a steel belt on the surface of the steel belt, performing homogenizing annealing in a high-temperature annealing furnace, and preserving heat for 10 hours at the temperature of 380 ℃. Heating to a target heating temperature of 430-480 ℃ according to 3-5 ℃/min, preserving heat for 3-5h after reaching the target heating temperature, cooling the furnace gas according to 5-8 ℃/min, discharging immediately when the furnace gas temperature reaches 280 ℃, and cooling by air to obtain a semi-finished product of the aluminum coil; and carrying out metallographic analysis on the homogenized coiled material, wherein the particle size of the second phase is controlled to be 1-5 mu m, and the second phase is uniformly distributed. Wherein the particles with the size of 1-3 μm account for more than 80%. After the standard is met, the next flow is carried out, the smaller the second phase size is, the probability of generating pinholes is reduced, otherwise, the second phase size is coarse, and high-density pinholes are generated.
(6) Cold rolling: rolling the semi-finished product obtained in the step (5) to 0.15-0.25mm, wherein the convexity of a working roll of a cold rolling mill is controlled to be 0.02-0.04mm, the roughness Ra value is controlled to be 0.2-0.3 mu m, the online plate shape is controlled to be 7-10I during rolling, the oil temperature is controlled to be 38-43 ℃, the oil nozzle flow is controlled to be 48-55%, and the acid value of an oil product is controlled to be 0.1-0.25mgKOH/g. Wherein the ash content of the rolling oil is controlled to be 5-8g/L.
(7) Foil rolling: transferring the material obtained in the step (6) to a foil rolling mill, and rolling for 3-5 times to obtain a finished product of 8-10 mu m, wherein the rolling oil additive is controlled to be 5-15% (weight percentage), the on-line plate type is controlled to be 3-5I, and the rolling oil temperature is controlled to be 40-50 ℃. And after the finished product is offline, offline pinhole inspection is carried out in a darkroom.
The aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery has the finished product of 50-60Hv in Vickers hardness, 260-280Mpa in tensile strength, elongation of more than or equal to 3.0% and less than or equal to 10 pinholes per square meter.
Advantageous effects
Compared with the traditional aluminum foil material for the positive current collector produced by hot rolling and cold rolling, the aluminum foil material for the positive current collector has the advantages of short flow, low energy consumption and the like. The conventional hot rolling process of the process part of the invention produces the same type of products, the period is reduced from 30 days to 15 days, the period is shortened by more than 15 days, and the production period is shortened by more than 30 percent; in terms of energy consumption and carbon emission, hot rolling milling surfaces and hot rolling procedures are omitted, and the energy consumption is reduced by more than 30%. The technical innovation has the following advantages that (a) the special pretreatment technology for the Fe element of the raw material is utilized to eliminate Fe 2 O 3 And Fe (Fe) 3 O 4 Foreign metal oxides that affect pinholes, etc.; (b) Simultaneously, the method is matched with online three-stage filtration to eliminate aluminum liquid inclusions, and mixed inert protective gas is introduced to prevent aluminum liquid slagging technology and the like; (c) The aluminum melt is refined in all directions by utilizing a smelting furnace composite multi-step refining technology, so that the purity of the aluminum melt is ensured, and after refining is finished, inert protective gas is introduced into the furnace to prevent the aluminum melt from being oxidized multiple times; (d) The homogenization treatment process and the cold foil rolling process are optimized, so that the particles of the material tend to be dispersed and distributed, the particle size is fine and uniform, wherein the particle size of the second phase is controlled to be 1-5 mu m, and the distribution is uniform. Wherein the particles with a size of 1-3 μm account for more than 80%, further reducing the generationProbability of pinholes; (e) Meanwhile, mn element is properly added according to the following steps: mn content=1:1, and the proportion is carried out until Fe element which is easy to form a coarse alloy phase forms an alpha-Al-Fe-Si ternary phase in preference to Si element; the rest of Fe element and MnAl 6 Forming a dispersion distributed substitutional solid solution (Mn, fe) Al 6 The alloy phase, and thus the second phase particle size in the material, is precisely controlled. Therefore, the aluminum foil material for the positive current collector has the characteristics of excellent mechanical property, low-density pinholes and the like, the Vickers hardness of the aluminum foil material is 50-60Hv, the tensile strength of the aluminum foil material is 260-280Mpa, and the elongation of the aluminum foil material is more than or equal to 3.0%. Compared with the aluminum foil material for producing the positive electrode current collector in the prior art, the aluminum foil material has the pinhole density of 50 per square meter, the pinhole number density of the aluminum foil material is less than or equal to 10 per square meter, and the pinhole density is greatly reduced to more than 80 percent. In the aspect of environmental protection, the process technology belongs to a green manufacturing technology, and compared with the traditional hot rolling technology, the process technology has wide application market, wherein the energy consumption and the carbon emission are reduced by more than 30 percent.
Detailed Description
The present invention will be described in further detail with reference to the following examples.
The production process of the aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery comprises the following steps of,
example 1:
(1) Preparing alloy components: according to the content of Fe (weight percentages below) of 0.4%, the content of Si of 0.05%, the content of Ti of 0.01%, the content of Mn of 0.35% and the balance of aluminum, wherein the sum of the weight percentages of Fe, si, ti, mn and Al is 100%. And (5) performing alloy element proportioning.
(2) Fe element pretreatment technology: the alloy in the step (1) is proportioned according to the proportion, the pretreated Fe element is added at the bottom of a smelting furnace, the pretreatment process is that the Fe element is put into 0.1 percent dilute nitric acid solution to be dissolved for 30min, the solution is transferred into deionized water to be cleaned for 1h, the solution is put into a drying box to remove water, 99.5 percent nitrogen protection gas is introduced into the drying box, the furnace gas temperature is 100 ℃, and the temperature is kept for 5h.
(3) A smelting furnace compound multi-step refining technology: after the aluminum water is flattened by 2/3, adding Si element and Mn element into the smelting furnace, and synchronously adding 2kg/t of covering agent of the aluminum water to prevent the aluminum liquid from further oxidizing and slagging. And (3) carrying out refining process for 2 hours, adding a refining agent according to the proportion of 1.5kg/t aluminum water, and simultaneously introducing mixed gas of nitrogen and argon (volume ratio, argon: nitrogen=1:1) for blowing powder for refining, wherein the refining is controlled according to 30 minutes, and the total steps are divided into 3 stages. The first stage, 0-10min, the refining route in the smelting furnace walks according to the W-shaped route; a second stage, 10-20min, wherein the refining route in the smelting furnace walks according to a 'type' route; a third stage, 20-30min, wherein a refining route in the smelting furnace walks according to a 'loop' route; after the operation is completed, nitrogen is introduced into the smelting furnace, the positive pressure in the furnace is maintained, and the furnace is kept still for 1h. And (5) carrying out a furnace reversing procedure after the scum is not seen on the surface of the visual aluminum liquid.
(4) On-line multistage composite filtration technology: introducing the aluminum water treated in the step (3) into a filter box, wherein the filter box adopts a three-stage filtering process, the mesh number of a first-stage filter plate is 30PPi, the temperature in the heat-insulating box is controlled at 720 ℃, and argon is introduced into the filter box; the mesh number of the second-stage filtering plate is 50PPi, the temperature in the heat insulation box is controlled at 714 ℃, and mixed gas of nitrogen and argon (volume ratio, argon: nitrogen=1:1) is introduced into the filtering box; the mesh number of the third-stage filter plate is 70PPi, the temperature in the incubator is controlled at 705 ℃, and nitrogen is introduced into the filter tank; and then the molten aluminum passes through a casting and rolling machine to obtain cast-rolled coil blanks with the thickness of 6.8 mm.
(5) Heat treatment technology: and (3) rolling the cast-rolled coil obtained in the step (4) for 2 passes, and then performing heat treatment. Welding an outer ring, tightening a steel belt on the surface of the steel belt, performing homogenizing annealing in a high-temperature annealing furnace, and preserving heat for 10 hours at the temperature of 380 ℃. Heating to a target heating temperature of 430 ℃ at 3 ℃/min, preserving heat for 5 hours after reaching the target heating temperature, cooling the furnace gas at 5 ℃/min, discharging immediately when the furnace gas temperature reaches 280 ℃, and cooling by air to obtain a semi-finished product of the aluminum coil; and carrying out metallographic analysis on the homogenized coiled material, wherein the particle size of the second phase is controlled to be 1-5 mu m, and the second phase is uniformly distributed. Wherein the particles with the size of 1-3 μm account for 85%.
(6) Cold rolling: rolling the semi-finished product obtained in the step (5) to 0.15mm, wherein the convexity of a working roll of a cold rolling mill is controlled to be 0.02mm, the roughness Ra value is controlled to be 0.2 mu m, the online plate type is controlled to be 7I during rolling, the oil temperature is controlled to be 38 ℃, the oil nozzle flow is controlled to be 48%, and the acid value of an oil product is controlled to be 0.1mgKOH/g. Wherein the ash content of the rolling oil is controlled at 5g/L.
(7) Foil rolling: transferring the material obtained in the step (6) to a foil mill, and rolling for 3-5 times to obtain a finished product of 8 mu m, wherein the rolling oil additive is controlled to be 5% (weight percentage), the online plate type is controlled to be 3I, and the rolling oil temperature is controlled to be 40 ℃. And after the finished product is offline, offline pinhole inspection is carried out in a darkroom.
The aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery has the finished product of 50Hv in Vickers hardness, 260Mpa in tensile strength, 3.2% in elongation and 6 pinholes per square meter.
Example 2:
(1) Preparing alloy components: according to the content of Fe (weight percentages below) of 0.55%, the content of Si of 0.1%, the content of Ti of 0.02%, the content of Mn of 0.45% and the balance of aluminum, wherein the sum of the weight percentages of Fe, si, ti, mn and Al is 100%. And (5) performing alloy element proportioning.
(2) Fe element pretreatment technology: the alloy in the step (1) is proportioned according to the proportion, the pretreated Fe element is added at the bottom of a smelting furnace, the pretreatment process is that the Fe element is put into 0.15 percent dilute nitric acid solution for dissolving for 20min, the Fe element is transferred into deionized water for cleaning for 2h, the Fe element is put into a drying box for removing water, 99.7 percent nitrogen protection gas is introduced into the drying box, the furnace gas temperature is 110 ℃, and the temperature is kept for 5h.
(3) A smelting furnace compound multi-step refining technology: after the aluminum water is flattened by 2/3, adding Si element and Mn element into the smelting furnace, and synchronously adding 3kg/t of covering agent of the aluminum water to prevent the aluminum liquid from further oxidizing and slagging. And (3) carrying out refining process for 4 hours, adding a refining agent according to the proportion of 2.0kg/t aluminum water, and simultaneously introducing mixed gas of nitrogen and argon (volume ratio, argon: nitrogen=1:1) for blowing powder for refining, wherein the refining is controlled according to 30 minutes, and the total steps are divided into 3 stages. The first stage, 0-10min, the refining route in the smelting furnace walks according to the W-shaped route; a second stage, 10-20min, wherein the refining route in the smelting furnace walks according to a 'type' route; a third stage, 20-30min, wherein a refining route in the smelting furnace walks according to a 'loop' route; after the operation is completed, nitrogen is introduced into the smelting furnace, the positive pressure in the furnace is maintained, and the furnace is kept still for 1h. And (5) carrying out a furnace reversing procedure after the scum is not seen on the surface of the visual aluminum liquid.
(4) On-line multistage composite filtration technology: introducing the aluminum water treated in the step (3) into a filter box, wherein the filter box adopts a three-stage filtering process, the mesh number of a first-stage filter plate is 30PPi, the temperature in the heat preservation box is controlled at 725 ℃, and argon is introduced into the filter box; the mesh number of the second-stage filter plate is 50PPi, the temperature in the incubator is controlled at 719 ℃, and mixed gas of nitrogen and argon (volume ratio, argon: nitrogen=1:1) is introduced into the filter chamber; the mesh number of the third-stage filter plate is 70PPi, the temperature in the incubator is controlled at 710 ℃, and nitrogen is introduced into the filter box; and then the molten aluminum passes through a casting and rolling machine to obtain cast-rolled coil blanks with the thickness of 6.8 mm.
(5) Heat treatment technology: and (3) rolling the cast-rolled coil obtained in the step (4) for 2 passes, and then performing heat treatment. Welding an outer ring, tightening a steel belt on the surface of the steel belt, performing homogenizing annealing in a high-temperature annealing furnace, and preserving heat for 10 hours at the temperature of 380 ℃. Heating to a target heating temperature of 480 ℃ at 5 ℃/min, preserving heat for 3 hours after reaching the target heating temperature, cooling the furnace gas at 8 ℃/min, discharging immediately when the furnace gas temperature reaches 280 ℃, and cooling by air to obtain a semi-finished product of the aluminum coil; and carrying out metallographic analysis on the homogenized coiled material, wherein the particle size of the second phase is controlled to be 1-5 mu m, and the second phase is uniformly distributed. Wherein the particles with the size of 1-3 μm account for 88%.
(6) Cold rolling: rolling the semi-finished product obtained in the step (5) to 0.25mm, wherein the convexity of a working roll of a cold rolling mill is controlled to be 0.04mm, the roughness Ra value is controlled to be 0.3 mu m, the online plate type is controlled to be 10I during rolling, the oil temperature is controlled to be 43 ℃, the oil nozzle flow is controlled to be 55%, and the acid value of an oil product is controlled to be 0.25mgKOH/g. Wherein the ash content of the rolling oil is controlled at 8g/L.
(7) Foil rolling: transferring the material obtained in the step (6) to a foil mill, and rolling for 3-5 times to obtain a finished product of 10 μm, wherein the rolling oil additive is controlled to be 15% (weight percentage), the online plate type is controlled to be 5I, and the rolling oil temperature is controlled to be 50 ℃. And after the finished product is offline, offline pinhole inspection is carried out in a darkroom.
The aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery has the finished product of the aluminum foil material with the Vickers hardness of 60Hv, the tensile strength of 280Mpa, the elongation of 3.8 percent and the number of pinholes of 3 per square meter.
Comparative example 1
Preparing alloy components: according to the content of Fe (weight percentages below) of 0.35%, the content of Si of 0.15%, the content of Ti of 0.05%, the content of Mn of 0.15% and the balance of aluminum, wherein the sum of the weight percentages of Fe, si, ti, mn and Al is 100%. And (5) performing alloy element proportioning. The remaining production steps are as in example 1, and the final product of the aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery is obtained, wherein the Vickers hardness of the final product is 45Hv, the tensile strength is 220Mpa, the elongation is 2.3%, and the number of pinholes is 45 per square meter.
Compared with the example 1, the example has the advantages that as the proportion of Fe, si and Mn is unreasonable, a large amount of Fe elements are not matched with corresponding alloy elements, so that coarse Fe-Al phases distributed in a needle shape appear in the subsequent production process of the example, and pinholes of the product are increased, and the number of pinholes is 45 per square meter; the mechanical property is reduced, the tensile strength is 220Mpa, and the elongation is 2.3%.
Comparative example 2
1) Preparing alloy components: according to the content of Fe (weight percentages below) of 0.4%, the content of Si of 0.05%, the content of Ti of 0.01%, the content of Mn of 0.35% and the balance of aluminum, wherein the sum of the weight percentages of Fe, si, ti, mn and Al is 100%. And (5) performing alloy element proportioning.
(2) A smelting furnace compound multi-step refining technology: and (3) proportioning the alloy in the step (1) according to the proportion, and after the aluminum liquid is flattened by 2/3, adding Si element and Mn element into a smelting furnace, and synchronously adding 2kg/t of covering agent of the aluminum liquid to prevent the aluminum liquid from further oxidizing and slagging. And (3) carrying out refining process for 2 hours, adding a refining agent according to the proportion of 1.5kg/t aluminum water, and simultaneously introducing mixed gas of nitrogen and argon (volume ratio, argon: nitrogen=1:1) for blowing powder for refining, wherein the refining is controlled according to 30 minutes, and the total steps are divided into 3 stages. The first stage, 0-10min, the refining route in the smelting furnace walks according to the W-shaped route; a second stage, 10-20min, wherein the refining route in the smelting furnace walks according to a 'type' route; a third stage, 20-30min, wherein a refining route in the smelting furnace walks according to a 'loop' route; after the operation is completed, nitrogen is introduced into the smelting furnace, the positive pressure in the furnace is maintained, and the furnace is kept still for 1h. And (5) carrying out a furnace reversing procedure after the scum is not seen on the surface of the visual aluminum liquid.
(3) On-line multistage composite filtration technology: introducing the aluminum water treated in the step (2) into a filter box, wherein the filter box adopts a three-stage filtering process, the mesh number of a first-stage filter plate is 30PPi, the temperature in the heat-insulating box is controlled at 720 ℃, and argon is introduced into the filter box; the mesh number of the second-stage filtering plate is 50PPi, the temperature in the heat insulation box is controlled at 714 ℃, and mixed gas of nitrogen and argon (volume ratio, argon: nitrogen=1:1) is introduced into the filtering box; the mesh number of the third-stage filter plate is 70PPi, the temperature in the incubator is controlled at 705 ℃, and nitrogen is introduced into the filter tank; and then the molten aluminum passes through a casting and rolling machine to obtain cast-rolled coil blanks with the thickness of 6.8 mm.
(4) Heat treatment technology: and (3) performing heat treatment after rolling the cast-rolled coil obtained in the step (3) for 2 passes. Welding an outer ring, tightening a steel belt on the surface of the steel belt, performing homogenizing annealing in a high-temperature annealing furnace, and preserving heat for 10 hours at the temperature of 380 ℃. Heating to a target heating temperature of 430 ℃ at 3 ℃/min, preserving heat for 5 hours after reaching the target heating temperature, cooling the furnace gas at 5 ℃/min, discharging immediately when the furnace gas temperature reaches 280 ℃, and cooling by air to obtain a semi-finished product of the aluminum coil; and carrying out metallographic analysis on the homogenized coiled material, wherein the particle size of the second phase is controlled to be 1-5 mu m, and the second phase is uniformly distributed. Wherein the particles with the size of 1-3 μm account for 85%.
(5) Cold rolling: rolling the semi-finished product obtained in the step (4) to 0.15mm, wherein the convexity of a working roll of a cold rolling mill is controlled to be 0.02mm, the roughness Ra value is controlled to be 0.2 mu m, the online plate type is controlled to be 7I during rolling, the oil temperature is controlled to be 38 ℃, the oil nozzle flow is controlled to be 48%, and the acid value of an oil product is controlled to be 0.1mgKOH/g. Wherein the ash content of the rolling oil is controlled at 5g/L.
(6) Foil rolling: transferring the material obtained in the step (5) to a foil mill, and rolling for 3-5 times to obtain a finished product of 8 mu m, wherein the rolling oil additive is controlled to be 5% (weight percentage), the online plate type is controlled to be 3I, and the rolling oil temperature is controlled to be 40 ℃. And after the finished product is offline, offline pinhole inspection is carried out in a darkroom.
The aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery has the finished product of 50Hv in Vickers hardness, 260Mpa in tensile strength, 3.2% in elongation and 35 pinholes per square meter.
Compared with the example 1, the example lacks the treatment process of Fe element, the oxide of Fe element is an important cause for causing the pinhole exceeding of the aluminum foil, the oxide of Fe generally exists in the aluminum foil in the form of inclusion, the thickness of the aluminum foil is thinned, the oxide of Fe is separated from the aluminum foil, the elongation rate of the surface of the finished product is 3.2%, the number of pinholes is 35 per square meter, the pinhole exceeding is formed, and the mechanical property is reduced.
Comparative example 3
(1) Preparing alloy components: according to the content of Fe (weight percentages below) of 0.4%, the content of Si of 0.05%, the content of Ti of 0.01%, the content of Mn of 0.35% and the balance of aluminum, wherein the sum of the weight percentages of Fe, si, ti, mn and Al is 100%. And (5) performing alloy element proportioning.
(2) Fe element pretreatment technology: the alloy in the step (1) is proportioned according to the proportion, the pretreated Fe element is added at the bottom of a smelting furnace, the pretreatment process is that the Fe element is put into 0.1 percent dilute nitric acid solution to be dissolved for 30min, the solution is transferred into deionized water to be cleaned for 1h, the solution is put into a drying box to remove water, 99.5 percent nitrogen protection gas is introduced into the drying box, the furnace gas temperature is 100 ℃, and the temperature is kept for 5h.
(3) On-line multistage composite filtration technology: introducing the aluminum water treated in the step (2) into a filter box, wherein the filter box adopts a three-stage filtering process, the mesh number of a first-stage filter plate is 30PPi, the temperature in the heat-insulating box is controlled at 720 ℃, and argon is introduced into the filter box; the mesh number of the second-stage filtering plate is 50PPi, the temperature in the heat insulation box is controlled at 714 ℃, and mixed gas of nitrogen and argon (volume ratio, argon: nitrogen=1:1) is introduced into the filtering box; the mesh number of the third-stage filter plate is 70PPi, the temperature in the incubator is controlled at 705 ℃, and nitrogen is introduced into the filter tank; and then the molten aluminum passes through a casting and rolling machine to obtain cast-rolled coil blanks with the thickness of 6.8 mm.
(4) Heat treatment technology: and (3) performing heat treatment after rolling the cast-rolled coil obtained in the step (3) for 2 passes. Welding an outer ring, tightening a steel belt on the surface of the steel belt, performing homogenizing annealing in a high-temperature annealing furnace, and preserving heat for 10 hours at the temperature of 380 ℃. Heating to a target heating temperature of 430 ℃ at 3 ℃/min, preserving heat for 5 hours after reaching the target heating temperature, cooling the furnace gas at 5 ℃/min, discharging immediately when the furnace gas temperature reaches 280 ℃, and cooling by air to obtain a semi-finished product of the aluminum coil; and carrying out metallographic analysis on the homogenized coiled material, wherein the particle size of the second phase is controlled to be 1-5 mu m, and the second phase is uniformly distributed. Wherein the particles with the size of 1-3 μm account for 85%.
(5) Cold rolling: rolling the semi-finished product obtained in the step (4) to 0.15mm, wherein the convexity of a working roll of a cold rolling mill is controlled to be 0.02mm, the roughness Ra value is controlled to be 0.2 mu m, the online plate type is controlled to be 7I during rolling, the oil temperature is controlled to be 38 ℃, the oil nozzle flow is controlled to be 48%, and the acid value of an oil product is controlled to be 0.1mgKOH/g. Wherein the ash content of the rolling oil is controlled at 5g/L.
(6) Foil rolling: transferring the material obtained in the step (5) to a foil mill, and rolling for 3-5 times to obtain a finished product of 8 mu m, wherein the rolling oil additive is controlled to be 5% (weight percentage), the online plate type is controlled to be 3I, and the rolling oil temperature is controlled to be 40 ℃. And after the finished product is offline, offline pinhole inspection is carried out in a darkroom.
The aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery has the finished product of the aluminum foil material with the Vickers hardness of 50Hv, the tensile strength of 260Mpa, the elongation of 3.2 percent and the number of pinholes of 55 per square meter.
Compared with the embodiment 1, the missing compound refining process in the embodiment, on one hand, the aluminum alloy is easy to react with air and water in materials in the smelting process, and the phenomenon that the hydrogen content of an aluminum melt exceeds the standard occurs; on the other hand, in the smelting process, the aluminum melt contacts with air, and slag formation occurs. Both of these phenomena require a refining process to treat, and if there is no refining process, the number of pinholes in this example is 55 per square meter, and the pinholes are out of specification.
Comparative example 4
(1) Preparing alloy components: according to the content of Fe (weight percentages below) of 0.4%, the content of Si of 0.05%, the content of Ti of 0.01%, the content of Mn of 0.35% and the balance of aluminum, wherein the sum of the weight percentages of Fe, si, ti, mn and Al is 100%. And (5) performing alloy element proportioning.
(2) Fe element pretreatment technology: the alloy in the step (1) is proportioned according to the proportion, the pretreated Fe element is added at the bottom of a smelting furnace, the pretreatment process is that the Fe element is put into 0.1 percent dilute nitric acid solution to be dissolved for 30min, the solution is transferred into deionized water to be cleaned for 1h, the solution is put into a drying box to remove water, 99.5 percent nitrogen protection gas is introduced into the drying box, the furnace gas temperature is 100 ℃, and the temperature is kept for 5h.
(3) A smelting furnace compound multi-step refining technology: after the aluminum water is flattened by 2/3, adding Si element and Mn element into the smelting furnace, and synchronously adding 2kg/t of covering agent of the aluminum water to prevent the aluminum liquid from further oxidizing and slagging. And (3) carrying out refining process for 2 hours, adding a refining agent according to the proportion of 1.5kg/t aluminum water, and simultaneously introducing mixed gas of nitrogen and argon (volume ratio, argon: nitrogen=1:1) for blowing powder for refining, wherein the refining is controlled according to 30 minutes, and the total steps are divided into 3 stages. The first stage, 0-10min, the refining route in the smelting furnace walks according to the W-shaped route; a second stage, 10-20min, wherein the refining route in the smelting furnace walks according to a 'type' route; a third stage, 20-30min, wherein a refining route in the smelting furnace walks according to a 'loop' route; after the operation is completed, nitrogen is introduced into the smelting furnace, the positive pressure in the furnace is maintained, and the furnace is kept still for 1h. And (5) carrying out a furnace reversing procedure after the scum is not seen on the surface of the visual aluminum liquid. And then the molten aluminum passes through a casting and rolling machine to obtain cast-rolled coil blanks with the thickness of 6.8 mm.
(4) Heat treatment technology: and (3) performing heat treatment after rolling the cast-rolled coil obtained in the step (3) for 2 passes. Welding an outer ring, tightening a steel belt on the surface of the steel belt, performing homogenizing annealing in a high-temperature annealing furnace, and preserving heat for 10 hours at the temperature of 380 ℃. Heating to a target heating temperature of 430 ℃ at 3 ℃/min, preserving heat for 5 hours after reaching the target heating temperature, cooling the furnace gas at 5 ℃/min, discharging immediately when the furnace gas temperature reaches 280 ℃, and cooling by air to obtain a semi-finished product of the aluminum coil; and carrying out metallographic analysis on the homogenized coiled material, wherein the particle size of the second phase is controlled to be 1-5 mu m, and the second phase is uniformly distributed. Wherein the particles with the size of 1-3 μm account for 85%.
(5) Cold rolling: rolling the semi-finished product obtained in the step (4) to 0.15mm, wherein the convexity of a working roll of a cold rolling mill is controlled to be 0.02mm, the roughness Ra value is controlled to be 0.2 mu m, the online plate type is controlled to be 7I during rolling, the oil temperature is controlled to be 38 ℃, the oil nozzle flow is controlled to be 48%, and the acid value of an oil product is controlled to be 0.1mgKOH/g. Wherein the ash content of the rolling oil is controlled at 5g/L.
(6) Foil rolling: transferring the material obtained in the step (5) to a foil mill, and rolling for 3-5 times to obtain a finished product of 8 mu m, wherein the rolling oil additive is controlled to be 5% (weight percentage), the online plate type is controlled to be 3I, and the rolling oil temperature is controlled to be 40 ℃. And after the finished product is offline, offline pinhole inspection is carried out in a darkroom.
The aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery has the finished product of 50Hv in Vickers hardness, 260Mpa in tensile strength, 3.2% in elongation and 30 pinholes per square meter.
In contrast to example 1, the present example lacks an online multistage composite filtration process, on the one hand, during the smelting process of aluminum alloy, nonmetallic oxides in the hearth and launder can mix into the aluminum melt, and due to the excessive density and size, conventional refining and degassing processes can not clean out the foreign matters, can continue to mix into the aluminum melt, and requires an online filtration process to process, and if there is no filtration process, the phenomenon of pinhole count of 30 per square meter and pinhole overscaling in this example can result.
The foregoing has shown and described the basic principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined in the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (4)
1. The preparation method of the aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery is characterized by comprising the following raw materials in percentage by mass: 0.4-0.55% of Fe, 0.05-0.1% of Si, 0.01-0.02% of Ti, 0.35-0.45% of Mn and the balance of aluminum; (Fe content-Si content): mn content = 1:1;
the preparation method comprises the following steps: according to the proportion of the raw materials, adding Fe element which is pretreated by dilute nitric acid, cleaned and dried at the bottom of a smelting furnace; after molten aluminum is 2/3 flattened, adding Si element and Mn element into a smelting furnace, synchronously adding a covering agent, and introducing mixed gas of nitrogen and argon to perform powder blowing refining; introducing molten aluminum into a filter box, performing tertiary filtration, and performing cast rolling through a casting and rolling machine to obtain cast-rolled coil blanks; rolling the cast-rolled coil blank for 2 passes, and then performing heat treatment; welding an outer ring, tightening a steel belt on the surface of the steel belt, and carrying out homogenizing annealing in a high-temperature annealing furnace to obtain a semi-finished product of the aluminum coil; cold rolling and foil rolling the obtained semi-finished product to a finished product thickness of 8-10 mu m;
the pretreatment steps of Fe element are as follows: dissolving Fe element in 0.1-0.15% dilute nitric acid solution for 20-30min, transferring into deionized water, cleaning for 1-2h, placing into a drying oven to remove water, introducing 99.5-99.7% nitrogen protection gas into the drying oven, maintaining the temperature of furnace gas at 100-110 ℃ for 3-5h;
the refining steps are as follows: adding a refining agent according to the proportion of 1.5-2.0kg/t of aluminum water, and simultaneously introducing mixed gas of nitrogen and argon to perform powder blowing refining, wherein the refining is controlled according to 30min, and the refining is divided into 3 stages; the first stage, 0-10min, the refining route in the smelting furnace walks according to the W-shaped route; a second stage, 10-20min, wherein the refining route in the smelting furnace walks according to a 'type' route; a third stage, 20-30min, wherein a refining route in the smelting furnace walks according to a 'loop' route; after the operation is finished, introducing nitrogen into the smelting furnace, keeping positive pressure in the furnace, and standing for 1h; when the scum is not seen on the surface of the visual aluminum liquid, a furnace reversing procedure is carried out;
in the three-stage filtration, the mesh number of the first-stage filter plate is 30ppi, the temperature in the heat preservation box is controlled at 720-725 ℃, and argon is introduced into the filter box; the mesh number of the second-stage filtering plate is 50ppi, the temperature in the incubator is controlled at 714-719 ℃, and mixed gas of nitrogen and argon is introduced into the filtering box; the mesh number of the third-stage filter plate is 70ppi, the temperature in the incubator is controlled at 705-710 ℃, and nitrogen is introduced into the filter tank;
the homogenizing annealing process comprises the following steps: preserving heat for 10h at the temperature of 380 ℃ of furnace gas; heating to a target heating temperature of 430-480 ℃ according to 3-5 ℃/min, preserving heat for 3-5h after reaching the target heating temperature, cooling the furnace gas according to 5-8 ℃/min, discharging immediately when the furnace gas temperature reaches 280 ℃, and cooling by air to obtain a semi-finished product of the aluminum coil; carrying out metallographic analysis on the homogenized coiled material, wherein the size of second phase particles is controlled to be 1-5 mu m, and the second phase particles are uniformly distributed; wherein the particles with the size of 1-3 μm account for more than 80%.
2. The method for preparing the aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery, which is disclosed in claim 1, is characterized in that convexity of a working roller of a cold rolling mill is controlled to be 0.02-0.04mm, roughness Ra value is controlled to be 0.2-0.3 mu m, on-line plate type is controlled to be 7-10I during rolling, oil temperature is controlled to be 38-43 ℃, oil nozzle flow is controlled to be 48-55%, oil acid value is controlled to be 0.1-0.25mgKOH/g, and ash content of rolling oil is controlled to be 5-8g/L.
3. The method for preparing the aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery, which is disclosed in claim 1, is characterized in that in the foil rolling process, the rolling oil additive is controlled to be 5-15%, the online plate type is controlled to be 3-5I, and the rolling oil temperature is controlled to be 40-50 ℃.
4. The preparation method of the aluminum foil material for the low-density pinhole anode current collector of the new energy lithium battery, which is disclosed in claim 1, is characterized in that the volume ratio of argon to nitrogen in the mixed gas of nitrogen and argon is 1:1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210201104.3A CN114703404B (en) | 2022-03-02 | 2022-03-02 | Aluminum foil material for low-density pinhole current collector of new energy lithium battery and preparation method of aluminum foil material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210201104.3A CN114703404B (en) | 2022-03-02 | 2022-03-02 | Aluminum foil material for low-density pinhole current collector of new energy lithium battery and preparation method of aluminum foil material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114703404A CN114703404A (en) | 2022-07-05 |
| CN114703404B true CN114703404B (en) | 2023-07-21 |
Family
ID=82166331
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210201104.3A Active CN114703404B (en) | 2022-03-02 | 2022-03-02 | Aluminum foil material for low-density pinhole current collector of new energy lithium battery and preparation method of aluminum foil material |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114703404B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116043070B (en) * | 2023-01-09 | 2024-11-08 | 江苏鼎胜新能源材料股份有限公司 | Preparation method of aluminum foil material for battery with low-density second-phase particles |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01218702A (en) * | 1988-02-26 | 1989-08-31 | Kobe Steel Ltd | Manufacture of aluminum foil base |
| JP2012224927A (en) * | 2011-04-21 | 2012-11-15 | Mitsubishi Alum Co Ltd | Aluminum alloy foil for positive electrode current collector of lithium ion battery, and method for manufacturing the same |
| JP2014040659A (en) * | 2012-07-26 | 2014-03-06 | Mitsubishi Alum Co Ltd | Manufacturing method of aluminum alloy foil for lithium ion secondary battery positive electrode collector, aluminum alloy foil for lithium ion secondary battery positive electrode collector, and lithium ion secondary battery |
| CN111349824A (en) * | 2020-04-03 | 2020-06-30 | 江苏鼎胜新能源材料股份有限公司 | Ultrathin single-sided smooth aluminum foil for lithium battery tab and preparation method thereof |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0693396A (en) * | 1992-09-14 | 1994-04-05 | Furukawa Alum Co Ltd | Production of aluminum foil excellent in strength and foil rollability |
| JP5898476B2 (en) * | 2010-12-14 | 2016-04-06 | 三菱アルミニウム株式会社 | Aluminum alloy foil for lithium ion battery positive electrode current collector and method for producing the same |
| CN103748713B (en) * | 2011-07-29 | 2016-03-16 | 株式会社Uacj | Aluminum alloy foil for electrode current collector and method for producing same |
| CN104213001B (en) * | 2014-09-08 | 2016-12-07 | 广西南南铝加工有限公司 | Cathode Foil low aluflex and preparation method thereof |
| CN110060871B (en) * | 2019-04-04 | 2021-07-09 | 乳源东阳光优艾希杰精箔有限公司 | Preparation method of 1XXX series cathode foil for aluminum electrolytic capacitor |
| CN111349825A (en) * | 2020-04-26 | 2020-06-30 | 江苏鼎胜新能源材料股份有限公司 | A preparation method for producing high-toughness battery aluminum foil by using short-flow casting and rolling billets |
| CN111607722B (en) * | 2020-07-09 | 2021-08-24 | 包头常铝北方铝业有限责任公司 | Aluminum foil for air conditioner and preparation method thereof |
-
2022
- 2022-03-02 CN CN202210201104.3A patent/CN114703404B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01218702A (en) * | 1988-02-26 | 1989-08-31 | Kobe Steel Ltd | Manufacture of aluminum foil base |
| JP2012224927A (en) * | 2011-04-21 | 2012-11-15 | Mitsubishi Alum Co Ltd | Aluminum alloy foil for positive electrode current collector of lithium ion battery, and method for manufacturing the same |
| JP2014040659A (en) * | 2012-07-26 | 2014-03-06 | Mitsubishi Alum Co Ltd | Manufacturing method of aluminum alloy foil for lithium ion secondary battery positive electrode collector, aluminum alloy foil for lithium ion secondary battery positive electrode collector, and lithium ion secondary battery |
| CN111349824A (en) * | 2020-04-03 | 2020-06-30 | 江苏鼎胜新能源材料股份有限公司 | Ultrathin single-sided smooth aluminum foil for lithium battery tab and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114703404A (en) | 2022-07-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113755722A (en) | High-strength and high-toughness heat-treatment-free aluminum alloy material and preparation method thereof | |
| CN101880802B (en) | Al-Mg series high magnesium aluminum alloy for automobile body plate and manufacturing method thereof | |
| CN111270109B (en) | Method for producing 8021 aluminum alloy soft packaging foil for lithium battery by cast rolling method | |
| WO2012079433A1 (en) | Low-zinc hot-dip aluminum alloy plating material with seven modification components and preparation method thereof | |
| CN114250402B (en) | A kind of manufacturing method of low carbon nitrogen-containing austenitic stainless steel rod | |
| CN110629077B (en) | High-yield-ratio air conditioner foil base material and preparation method thereof | |
| CN112143975A (en) | Economical high-efficiency X70-grade pipeline steel and manufacturing method thereof | |
| WO2021189621A1 (en) | S355g10+n-thickness steel plate for offshore structure and production method therefor | |
| CN108486506A (en) | A kind of preparation method and application of high-performance low-density steel plate | |
| CN116695022A (en) | A kind of high strength and toughness gear round steel for wind power and its preparation method | |
| CN114703404B (en) | Aluminum foil material for low-density pinhole current collector of new energy lithium battery and preparation method of aluminum foil material | |
| CN118531263A (en) | Aluminum foil for lithium ion battery and production method thereof | |
| CN113881874A (en) | Foil blank for new energy battery and preparation method thereof | |
| CN117758142A (en) | A method of preparing steel for automobile engine rotors | |
| CN114657467B (en) | A kind of production method of yield strength 415MPa grade weathering steel plate | |
| CN117144101A (en) | A production method for thin-gauge, low-cost normalized rolled steel plate Q355NE | |
| CN110629128A (en) | A kind of FeCrAlZr cladding material and preparation method | |
| CN114737036A (en) | Preparation method of high-plasticity titanium alloy ultrathin plate for hydrogen fuel cell bipolar plate | |
| CN107815593A (en) | A kind of economical high-aluminum low-silicon TRIP steel of automobile using and preparation method thereof | |
| CN115386800B (en) | A low-carbon, high-manganese-sulfur environmentally friendly free-cutting steel and its manufacturing method | |
| CN117210760A (en) | Low-carbon austenitic high-toughness plastic light steel and preparation method thereof | |
| CN117144197A (en) | 3105 aluminum alloy sheet for pot shell and mobile phone lithium battery shell and preparation method thereof | |
| CN116987932A (en) | Aluminum foil for earphone voice coils made of cast-rolled 3003 aluminum alloy packaging material and its preparation method | |
| AU2023266433A1 (en) | Ultralow-carbon cold-rolled high-strength steel applicable to electrostatic dry powder enamel, and manufacturing method therefor | |
| CN111057828B (en) | High-oxygen enamel steel and production method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |