JP2001319641A - Manufacturing method of non-aqueous electrolyte secondary battery - Google Patents

Abstract

(57) [Problem] To provide a method for manufacturing a non-aqueous electrolyte secondary battery which can be achieved with simpler equipment. A method of manufacturing a non-aqueous electrolyte secondary battery according to the present invention includes an electrode body forming step of forming an electrode body by stacking a positive electrode, a negative electrode, and a separator sandwiched between the positive electrode and the negative electrode. A method for inserting a non-aqueous electrolyte into the case, and a step for injecting a non-aqueous electrolyte into the case. An electrode body drying step of drying the electrode body is provided between the electrode body forming step and the non-aqueous electrolyte injecting step.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a non-aqueous electrolyte secondary battery using a non-aqueous electrolyte as an electrolyte.

[0002]

2. Description of the Related Art In recent years, there has been a high demand for a secondary battery which can be made lighter and smaller as a power source for driving portable equipment. Among them, non-aqueous electrolyte secondary batteries, particularly lithium secondary batteries, are highly expected as batteries having high voltage and high energy density.

In general, a lithium secondary battery has a laminated electrode body in which a belt-like positive electrode and a belt-like negative electrode are laminated by winding or the like through a separator made of a porous material, and an electrolyte dissolved in an organic solvent. It is constituted by storing the electrolyte solution in a case.

An electrolyte used in a non-aqueous electrolyte battery such as a lithium secondary battery has high reactivity with moisture, so that the battery manufacturing process is carried out in a battery so that moisture does not enter the electrolyte. Batteries are manufactured after sufficiently drying electrodes and other materials.

Specifically, in a conventional method of manufacturing a non-aqueous electrolyte secondary battery, a positive electrode and a negative electrode are processed to a predetermined thickness and width in order to remove water from an electrode or the like or to suppress re-adsorption. Before and after the drying, a drying process is performed at a high temperature.
After that, it is carried into a drying room such as a dry room, where main processes such as winding, storage in a case, injection of an electrolytic solution, and hermetically sealing the case are performed.

[0006] Further, since the non-aqueous electrolyte has a higher viscosity than the aqueous solvent-based electrolyte, a method of lowering the viscosity by heating when injected into a case is disclosed in JP-A-10-28412.
However, these heating facilities also need to be installed in the dry room.

[0007]

However, in the conventional method of manufacturing a non-aqueous electrolyte secondary battery, not only an expensive dry room facility is required in the manufacturing process, but also water management in many steps after the electrode is dried. The labor required for this is also enormous.

[0008] Introducing a heating facility into a dry room increases the scale of the dry room, which further increases the cost.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method of manufacturing a nonaqueous electrolyte secondary battery which can be achieved with simpler equipment.

[0010]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have made the following inventions.

That is, the method for producing a non-aqueous electrolyte secondary battery according to the present invention comprises a method in which a positive electrode, a negative electrode, and a separator sandwiched between the positive electrode and the negative electrode are stacked and laminated or wound. Non-aqueous electrolysis comprising an electrode body forming step of forming an electrode body, an electrode body inserting step of inserting the electrode body into a case, and a non-aqueous electrolyte solution injecting step of a non-aqueous electrolyte solution into the case. A method for manufacturing a liquid secondary battery, comprising an electrode body drying step of drying the electrode body between the electrode body forming step and the non-aqueous electrolyte injecting step.

That is, in the method of manufacturing a nonaqueous electrolyte secondary battery of the present invention, the drying step is performed after the formation of the electrode body, so that the drying process is performed before and after processing the positive electrode, the negative electrode, and the like, as in the related art. The drying step and the step of transporting the dried positive electrode or the like into a drying chamber such as a dry room when forming the dried positive electrode or the like on the electrode body can be collectively performed. Therefore, the drying process can be simplified, and the equipment can be simplified.

Further, the drying step is preferably performed with the electrode body inserted in the case.

[0014] This is because it is possible to save the trouble of housing the dried electrode body in the case, and it is possible to dry and remove moisture adhering to the inner wall of the case by heating the case.

Preferably, the electrode body drying step is a step of heating the electrode body under reduced pressure to a temperature equal to or higher than the boiling point of water under the reduced pressure.

This is because, when drying under reduced pressure, drying proceeds rapidly at the same temperature, and as described above, the drying temperature can be lowered to a temperature that does not affect the separator.

Therefore, the method for manufacturing a non-aqueous electrolyte secondary battery of the present invention can more reliably perform drying of the electrode body, and can provide a non-aqueous secondary battery with higher performance.

Further, the electrode body drying step is preferably a step of heating the electrode body to a temperature of 100 ° C. or more.

Since the boiling point of water is 100 ° C. at normal pressure,
When the temperature is raised to 100 ° C. or more, the electrode body can be surely dried.

Therefore, the method for producing a non-aqueous electrolyte secondary battery of the present invention can more reliably perform drying of the electrode body, and can provide a non-aqueous secondary battery with higher performance.

The melting point of the separator is preferably at least 150.degree. This is to prevent the separator from thermally contracting due to heat in the electrode body drying step. Therefore, a short circuit between the positive electrode and the negative electrode can be avoided.

Further, in the electrode body drying step, it is preferable that a contraction rate of the separator before and after the electrode body drying step is 5% or less.

In the electrode body drying step, the separator
When the shrinkage is less than 10%, the insulation, which is the original function of the separator, cannot be ensured. Therefore, on the contrary, it is preferable that the separator has a shrinkage ratio of 5% or less before and after the electrode body drying step. Here, the shrinkage is defined as [{(length before drying) − (length after drying)} / (length before drying)] × 100 similarly to the shrinkage determined by the measurement method of ASTM-D1204. Is the value defined by

Therefore, the method of manufacturing a non-aqueous electrolyte secondary battery of the present invention can manufacture a non-aqueous electrolyte secondary battery without risk of impairing the original function of the battery.

Further, the non-aqueous electrolyte injecting step includes:
It is preferable that the heating is performed after the temperature of the electrode body is cooled to a predetermined temperature of 50 ° C. or more.

When the non-aqueous electrolyte is injected when the temperature of the electrode body after the drying step is 50 ° C. or higher, there is no need to perform a separate heating step for reducing the viscosity of the non-aqueous electrolyte. Because.

Therefore, the method for producing a non-aqueous electrolyte secondary battery of the present invention can further reduce the number of production steps.

Preferably, the non-aqueous electrolyte injected in the non-aqueous electrolyte injection step has a flash point of at least 70 ° C. This is because even if the electrolyte is injected at a high temperature, no ignition occurs, and both safety and productivity can be achieved.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A manufacturing method according to this embodiment includes an electrode body forming step, an electrode body inserting step, a non-aqueous electrolyte injection step, and an electrode body forming step and the non-aqueous electrolyte injection step. And an electrode body drying step between them.

The manufacturing method will be described below based on a method for manufacturing a lithium ion secondary battery as a non-aqueous electrolyte battery. In the present embodiment, the present invention will be described by taking a lithium ion secondary battery as an example, but the method of manufacturing a nonaqueous electrolyte secondary battery of the present invention is limited to the method of manufacturing a lithium ion secondary battery. However, the present invention can be applied to any non-aqueous electrolyte secondary battery having a non-aqueous electrolyte which needs to avoid mixing of water. In addition, the figures are schematic views, and dimensions and forms are not accurate.

A lithium ion secondary battery is a lithium-ion battery capable of occluding and releasing lithium ions as a positive electrode active material.
A lithium ion secondary battery includes a positive electrode having a metal composite oxide as a positive electrode active material layer and a negative electrode capable of inserting and extracting lithium ions.

The lithium ion secondary battery of the present embodiment is
The shape is not particularly limited, and it can be used as batteries of various shapes such as a coin type, a cylindrical type, and a square type. The present embodiment will be described based on a cylindrical lithium ion secondary battery as shown in FIG.

FIG. 1 shows a partial cutaway view of a cylindrical lithium ion secondary battery in this embodiment. In the lithium ion secondary battery of the present embodiment, the positive electrode 1 and the negative electrode 2 are formed in a sheet shape, both of which are laminated via a separator 4, and a spirally wound spirally wound electrode is formed together with the electrolytic solution 3 filling the voids. Are stored in the cylindrical case 7. Positive electrode 1 and positive electrode terminal 5 and negative electrode 2
And the negative electrode terminal 6 are electrically connected to each other.

The wound electrode is composed of a positive electrode 1, a negative electrode 2, and a separator 4. The positive electrode 1 and the negative electrode 2 are formed in a sheet shape, and both are laminated via the separator 4, and are wound in a spiral form many times. .

The form of the electrode body is not particularly limited. In addition to a cylindrical wound electrode body, a square wound electrode body or an electrode is not wound, and a plurality of positive and negative electrodes are not wound. May be a laminated electrode body laminated via a separator.

The electrode body forming step includes a positive electrode 1, a negative electrode 2, and a positive electrode 1.
And the step of forming an electrode body by overlapping the separator 4 sandwiched between the negative electrode 2.

Specifically, the ends of the positive electrode 1, the negative electrode 2, and the separator 4 are attached to a winding core, and the positive electrode 1 is attached to the winding core.
The electrode body is formed by winding the like.

Further, it is necessary to connect the positive electrode side and the negative electrode side of the formed electrode body to the positive electrode terminal part 5 and the negative electrode terminal part 6, respectively, but the connection can be made before or after the electrode body forming step. For example, the positive electrode 1 before forming the electrode body
And leads 13, 2 connected to terminals 5, 6 on negative electrode 2.
3 may be connected, or may be connected during or after the formation of the electrode body.

Here, the positive electrode 1 has a lithium-metal composite oxide capable of releasing lithium ions during charging and occluding during discharging, as a positive electrode active material. Lithium-
The metal composite oxide has excellent performance of the active material, such as excellent diffusion performance of electrons and lithium ions. Therefore, when such a composite oxide of lithium and transition metal is used for the positive electrode active material, high charge / discharge efficiency and good cycle characteristics can be obtained. Further, as the positive electrode 1, it is preferable to use a material obtained by applying a positive electrode mixture obtained by mixing a positive electrode active material, a conductive material and a binder to a current collector.

The positive electrode active material includes a lithium-metal composite oxide.
Is not particularly limited as long as it is a known active material.
Can be used. For example, Li_(1-X)NiO_Two,
Li _(1-X)MnO_Two, Li_(1-X)Mn_TwoO_Four, Li_(1-X)Co
O_TwoAnd transition metals such as Li, Al, and Cr, respectively.
Materials added or substituted are exemplified. The positive electrode active
Limited to the case where one kind of substance is used alone
Instead, a plurality of substances may be used as a mixture. And
X in the example of this positive electrode active material shows the number of 0-1.

If the negative electrode 2 can occlude lithium ions during charging and release lithium ions during discharging,
The material configuration is not particularly limited, and a known material configuration can be used. In particular, it is preferable to use a material obtained by applying a negative electrode mixture obtained by mixing a negative electrode active material, a conductive material and a binder to a current collector.
The negative electrode active material is not particularly limited by the type of the active material, and a known negative electrode active material can be used. Above all, carbon materials such as natural graphite and artificial graphite having high crystallinity have excellent performance of active materials such as excellent lithium ion occlusion performance and diffusion performance. Therefore, when such a carbon material is used for the negative electrode active material, high charge / discharge efficiency and good cycle characteristics can be obtained. Further, it is more preferable to use lithium metal or a lithium alloy as the negative electrode 2 from the viewpoint of battery capacity.

The description of the separator 4 will be described later together with the description of the electrode body drying step.

The electrode body inserting step is a step of inserting the electrode body into the case 7.

The shape and material of the case 7 are not particularly limited in applying the present invention. In general, cylindrical and square shapes are well known. Further, the material needs to be a material which is electrochemically stable in relation to the electrolytic solution 3 as an internal non-aqueous electrolytic solution. For example, it can be made of a metal such as stainless steel, aluminum, or copper, or made of a resin.

The case 7 has a gasket 72 sandwiched between the case 7, the lid 71, and the positive and negative terminal portions 5 and 6 in order to maintain the sealing property, the insulating property and the like. Gasket 7
Numeral 2 secures electrical insulation between the case and the terminal portions 5 and 6 and hermeticity in the case 7. The gasket 72 can be made of, for example, a polymer such as polypropylene which is chemically and electrically stable with respect to the electrolyte 3.

The non-aqueous electrolyte injection step is a step of injecting the electrolyte 3 as a non-aqueous electrolyte into the case 7.

The electrolyte 3 is obtained by dissolving an electrolyte in an organic solvent.

The organic solvent is not particularly limited as long as it is an organic solvent usually used in an electrolyte of a lithium ion secondary battery. Examples thereof include a carbonate compound, a lactone compound, an ether compound, a sulfolane compound, a dioxolan compound, and a ketone. Examples include compounds, nitrile compounds, halogenated hydrocarbon compounds, and the like.

Specifically, carbonates such as dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, ethylene carbonate, propylene carbonate, ethylene glycol dimethyl carbonate, propylene glycol dimethyl carbonate, ethylene glycol diethyl carbonate, vinylene carbonate, and γ-butyl lactone Lactones such as dimethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, ethers such as tetrahydropyran and 1,4-dioxane, sulfolane such as sulfolane and 3-methylsulfolane, dioxolanes such as 1.3-dioxolan and 4, -Ketones such as -methyl-2-pentanone, and nitriles such as acetonitrile, pyropionitrile, pareronitrile, and benzonitrile Halogenated hydrocarbons such as 1,2-dichloroethane, other methyl formate,
Examples thereof include dimethylformamide, dimethylformamide, and dimethylsulfoxide. These may be used alone or in a mixture of a plurality of organic solvents selected from these.

By using one or more non-aqueous solvents selected from the group consisting of carbonates and ethers among these organic solvents mentioned in the examples, the solubility, dielectric constant and viscosity of the electrolyte are improved. This is preferable because the charge and discharge efficiency of the battery is high. Further, those having a high flash point are preferable from the viewpoint of easiness in injecting an electrolytic solution described later. In particular, it is preferable to use an electrolyte having a flash point of 70 ° C. or higher. The flash point can be improved by, for example, mixing a phosphate ester.

The type of the electrolyte is not particularly limited, but an inorganic salt selected from LiPF ₆ , LiBF ₄ , LiClO ₄ and LiAsF ₆ , a derivative of the inorganic salt,
LiSO ₃ CF ₃ , LiC (SO ₃ CF ₃ ) ₂ and LiN
It is preferably at least one kind of an organic salt selected from (SO ₃ CF ₃ ) ₃ and a derivative of the organic salt.

With this electrolyte, the battery performance can be further improved, and the battery performance can be maintained even higher in a temperature range other than room temperature.

The concentration of the electrolyte is not particularly limited either, and it is preferable to appropriately select the concentration in consideration of the type of the electrolyte and the organic solvent according to the application.

The electrode body drying step is a step of drying the electrode body to such an extent that it can be used in a lithium ion secondary battery. In the lithium ion secondary battery, the electrolyte solution 3 is consumed and deteriorated due to the remaining water.
This step is performed between the electrode body forming step and the non-aqueous electrolyte injection step. More preferably, after the electrode body insertion step,
This step is preferably performed immediately before the nonaqueous electrolyte injection step with the electrode body inserted in the case. The reason for this is that the time for keeping the substrate in a dry state is shortened, and the intrusion of moisture can be prevented without using a special device.

After this step, it is necessary to continue the production operation in a dry atmosphere or to carry out the subsequent operation promptly to prevent water from entering.

Examples of the method of drying the electrode body include a method of heating the electrode body to a temperature higher than the boiling point of water, a method of extracting moisture with a dried liquid or gas, and the like. preferable.

Heating is preferred because heating to a temperature equal to or higher than the boiling point of water under reduced pressure enables more rapid removal of water. It is more preferable to perform the heating by heating to 100 ° C. or more.

When this step is performed by heating, it is preferable to perform the above-described nonaqueous electrolyte injection step after cooling the electrode body to a predetermined temperature of 50 ° C. or higher. Since the viscosity of the electrolyte 3 decreases as the temperature increases, the injection of the electrolyte 3 at a high temperature allows the electrolyte 3 to penetrate into the case 7 and the electrode faster. Here, the predetermined temperature is not particularly limited, but it is preferable that the predetermined temperature be as high as possible.
Is preferred from the viewpoint of lowering the viscosity of the polymer. However, if the temperature is too high and the flash point is higher than the flash point of the organic solvent used for the electrolytic solution 3, capital investment for preventing ignition is required. Therefore, the flash point is preferably lower than the flash point of the organic solvent used.
For example, when ethylene carbonate or diethylene carbonate is used as the organic solvent, the temperature is preferably set to 70 ° C. or lower.

When drying by heating in the electrode body drying step, it is preferable that the contraction rate of the separator 4 before and after this step is 5% or less. To control the shrinkage, there is a method of changing the material of the separator 4 or changing the drying temperature.

The separator 4 electrically insulates the positive electrode 1 and the negative electrode 2, holds the electrolytic solution 3, and
It plays a role of ensuring conduction between the materials, and the material constituting the separator 4 preferably has high insulation properties.
In addition, it is preferable to have intermolecular gaps or pores that do not impede the transmission of ions. For example, a microporous film can be used as the separator 4.

The material of the separator 4 is polybenzimidazole, polyimide, polyetherimide, polyamideimide, polyphenylene ether (polyphenylene oxide), polyarylate, polyacetal, polyphenylene sulfide, polyether sulfone, polysulfone, polyether ketone having a high melting point. , Polyester resin, polyethylene naphthalate, ethylene-cycloolefin copolymer, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer, and the like. Among them, polyphenylene ether and polyester resin (for example, polyethylene Terephthalate, polybutylene terephthalate)
It is preferable to contain at least one or more of these from the viewpoint of resistance to electrolyte. Further, the melting point of the separator is 15
The temperature is preferably set to 0 ° C. or higher for the purpose of imparting further electrolytic solution resistance.

As a method for manufacturing the separator 4, a solution obtained by dissolving the above-mentioned resin or the like in a good solvent is applied on a flat plate,
It is manufactured by a chemical method such as immersion in a poor solvent or a physical method such as stretching the above-mentioned resin melt-molded into a film. The size of the separator 4 is the same as that of the positive electrode 1 and the negative electrode 2.
In order to ensure the insulation of the positive electrode 1 and the negative electrode 2 more securely, it is preferable that the positive electrode 1 and the negative electrode 2 have larger sizes. In this case, it is preferable to increase the size of the separator 4 so that the separator 4 protrudes from the electrode body to some extent, because even if the separator 4 shrinks in the electrode drying step, the separation between the electrodes can be more reliably achieved.

[0063]

The present invention will be further described below with reference to examples.

Example 1 (Method of Manufacturing Battery) A lithium ion secondary battery shown in FIG. 1 was manufactured as follows.

The positive electrode plate 1 is composed of 85 parts by weight of lithium manganate as an active material, 10 parts by weight of acetylene black as a conductive material, and 5 parts by weight of polyvinylidene fluoride as a binder.
The mixture obtained by kneading the mixture by weight with a mixture of
It is applied and pressed on both sides of a current collector of aluminum foil of μm. Further, the negative electrode plate 2 is obtained by kneading 92.5 parts by weight of carbon as an active material and 7.5 parts by weight of polyvinylidene fluoride as a binder, and mixing a paste into a paste.
It is applied and pressed on both surfaces of a copper foil current collector having a thickness of 10 μm. Each of the positive electrode plate 1 and the negative electrode plate 2 has an uncoated portion where the mixture is not applied,
A plurality of aluminum leads 13 are provided on the surface of the uncoated portion 111 of the positive electrode current collector 11, and a plurality of copper leads 23 are provided on the surface of the uncoated portion 211 of the negative electrode current collector 21. Were joined by an ultrasonic welding method for extracting current from the positive electrode terminal 5 and the negative electrode terminal 6.

Next, between the positive electrode plate 1 and the negative electrode plate 2, a separator 4 which is cut so as to be wide so that the positive electrode plate 1 and the negative electrode plate 2 do not come into direct contact with each other is spirally wound. A turn electrode body was produced. At this time, a film obtained by subjecting polyphenylene ether to a porous treatment was used as the separator 4.

Subsequently, the leads 13 and 23 attached to the positive electrode plate 1 and the negative electrode plate 2 are subjected to convergence processing, and are joined to the positive electrode terminal portion 5 and the negative electrode terminal portion 6 by ultrasonic welding, respectively, and then stored in the battery can 7. A gasket 7 is provided between the positive terminal 5 and the cover plate 71 and between the negative terminal 6 and the battery can 7, respectively.
2 with the nut 8 interposed, and the cover plate 71
And the battery can 7 were joined by a laser welding method under welding conditions that maintain airtightness and liquid tightness.

The battery in which the electrode body was housed in the battery can prepared as described above was housed in a drying furnace and stored for 8 hours while reducing the pressure to 133 Pa and further heating to 120 ° C.
Thereafter, the electrolyte injection opening 711 previously set in the lid 71 is transported to the electrolyte injection device in a state of being temporarily sealed with a sealing part made of EPDM, and the sealing part is removed. A non-aqueous electrolyte was injected from the opening 711 for injection of an electrolyte. The non-aqueous electrolyte used was one in which lithium hexafluorophosphate was dissolved in a solvent in which ethylene carbonate and diethylene carbonate were mixed at a weight ratio of 3: 7. After injecting a predetermined amount of the electrolytic solution, the injection opening 711 was hermetically and liquid-tightly sealed with the sealing plug 9. This was subjected to a test as a battery of Example 1.

<Comparative Example 1> The drying temperature was set to 80 ° C.
A battery was prepared in exactly the same manner as in Example 1 except that the battery was changed to, and subjected to a test as a battery of Comparative Example 1.

<Embodiment 2> The drying temperature was set to 100
A battery was prepared in exactly the same manner as in Example 1 except that the temperature was changed to ° C., and was subjected to a test as the battery of Example 2.

<Embodiment 3> The drying temperature was set to 150.
A battery was prepared in exactly the same manner as in Example 1 except that the temperature was changed to ° C., and was subjected to a test as the battery of Example 3.

<Comparative Example 2> A battery was produced in exactly the same manner as in Example 1 except that a porous film made of polyethylene was used as the separator and the drying temperature was 100 ° C. This was subjected to a test as a battery of Comparative Example 2.

<Tests and Results> The battery was disassembled, the amount of water contained in the positive electrode plate was measured, and at the same time, the state of the separator was observed.

Table 1 shows the measurement results of the battery capacities of the battery of this example and the comparative battery.

[0075]

[Table 1]

In the batteries of the examples, almost the same battery capacity was obtained, but in the battery of Comparative Example 1, a decrease in the battery capacity was observed. From the results of the water content, the electrode plate in the battery was not sufficiently removed under the conditions of Comparative Example 1. In the battery of Comparative Example 2, the polyethylene separator was extremely shrunk at a drying temperature of 100 ° C., and the battery capacity could not be measured due to short-circuiting and charge / discharge.

Thus, according to the method of manufacturing a battery using a separator having a heat shrinkage temperature of 100 ° C. or higher and a drying temperature of 100 ° C. or higher, it is possible to manufacture the battery without using expensive facilities such as a dry room. Thus, a lithium secondary battery can be provided at low cost.

Example 4 The battery of Example 4 was manufactured in exactly the same manner as in Example 1 except for the steps from manufacturing the electrode plate to drying. Next, the flash point 70
The electrolyte was injected using a solution of lithium hexafluorophosphate dissolved in a solvent at a temperature of ° C. At this time, a solvent in which ethylene carbonate and triethyl phosphate were mixed at a weight ratio of 1: 1 was used as a solvent of the non-aqueous electrolyte. As the conditions for injecting the electrolyte, first, the battery before the injection of the electrolyte which had been heated and dried to 120 ° C. before taking out the electrolyte was taken out of the drying oven, and then allowed to stand until the battery temperature reached 70 ° C. by natural cooling under room temperature environment. After the standing, the pressure inside the battery was reduced to 4000 Pa, and then the pressure was released to the atmospheric pressure. At the same time, a predetermined amount of the electrolyte was injected. The time required for the battery temperature to be cooled to 70 ° C. was 10 minutes. Thereafter, a battery was manufactured in the same manner as in Example 1 until the opening for injecting the electrolyte was sealed.

In this case, the time when the electrolytic solution permeated the wound electrode when the electrolytic solution was injected and the internal resistance became substantially constant was measured.

Comparative Example 3 A battery was prepared in exactly the same manner as in Example 5 except that after drying, the battery was allowed to stand for about 1 hour until the battery temperature was substantially equal to room temperature. Similarly, for the battery of Example 3, the time during which the electrolytic solution permeated the wound electrode during the injection of the electrolytic solution was measured. Tested.

<Results> The results are shown in Table 2.

[0082]

[Table 2]

It is understood that the time required for infiltration of the electrolyte can be significantly reduced by injecting the battery at a high temperature.

Thus, a battery with high productivity can be provided by utilizing the heating of the battery during drying and using an electrolytic solution having a high flash point.

[Brief description of the drawings]

FIG. 1 is a partially cutaway view showing the overall configuration of a cylindrical lithium ion secondary battery.

[Explanation of symbols]

1: Positive electrode 11: Positive electrode collector 111: Uncoated portion 12: Positive electrode mixture layer 13: Positive electrode lead 2: Negative electrode 21: Negative electrode collector 211: Uncoated portion 22: Negative electrode mixture layer 23: Negative electrode lead 3: Non-aqueous electrolyte 4: Separator 5: Positive terminal 6: Negative terminal 7: Case

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Uejima 1-1-1, Showa-cho, Kariya-shi, Aichi Pref. F term (for reference) 5H021 CC17 HH00 HH01 HH06 5H023 AA03 AS01 BB01 BB05 5H028 AA01 AA05 BB03 BB05 CC12 HH08 HH09 5H029 AJ14 AK03 AL06 AM03 AM04 AM05 AM07 BJ02 BJ14 CA13JJA14J13CA14 GA27 HA14

Claims (8)

[Claims] An electrode body forming step of forming an electrode body by laminating a positive electrode, a negative electrode, and a separator sandwiched between the positive electrode and the negative electrode; and inserting the electrode body into a case. And a non-aqueous electrolyte injecting step of injecting a non-aqueous electrolyte into the case. A method for manufacturing a non-aqueous electrolyte secondary battery, comprising: the electrode body forming step and the non-aqueous electrolyte injecting. A method for manufacturing a nonaqueous electrolyte secondary battery, comprising an electrode body drying step of drying the electrode body between the steps. 2. The non-aqueous electrolyte according to claim 1, wherein the electrode body drying step is performed in a state where the electrode body is inserted into the case after the electrode body insertion step. A method for manufacturing a secondary battery. 3. The non-aqueous electrolyte according to claim 1, wherein the electrode body drying step is a step of heating the electrode body under reduced pressure to a temperature equal to or higher than the boiling point of water under reduced pressure. A method for manufacturing a secondary battery. 4. The method according to claim 1, wherein the electrode body drying step comprises:
The method for producing a non-aqueous electrolyte secondary battery according to claim 1 or 2, wherein the method is a step of heating to a temperature of 00 ° C or higher. 5. The separator having a melting point of at least 1
The method for producing a non-aqueous electrolyte secondary battery according to claim 1, wherein the temperature is 50 ° C. or higher. 6. The non-aqueous electrolyte secondary battery according to claim 1, wherein in the electrode body drying step, a contraction rate of the separator before and after the electrode body drying step is 5% or less. Production method. 7. The non-aqueous electrolyte secondary according to claim 1, wherein the non-aqueous electrolyte injection step is performed after cooling the temperature of the electrode body to a predetermined temperature of 50 ° C. or higher. Battery manufacturing method. 8. The non-aqueous electrolyte according to claim 1, wherein the non-aqueous electrolyte injected in the non-aqueous electrolyte injection step has a flash point of at least 70 ° C. or higher. A method for manufacturing an electrolyte secondary battery.