CN106601979A - Anode of secondary battery - Google Patents

Abstract

The invention discloses an anode of a secondary battery, and belongs to the field of batteries. The anode of the secondary battery disclosed by the invention comprises a current collector and an active layer coated on the surface of the current collector, the active layer is of a three-dimensional porous structure, and signal peptides are filled among holes of the active layer. The anode of the secondary battery disclosed by the invention has the characteristics that the specific capacity of the battery can be improved, and specifically high specific capacity still can be maintained under the condition of high current density, so that the charging rate of the battery and the cruising power of the battery are improved.

Description

A negative electrode of a secondary battery

technical field

The invention relates to an electrode material, in particular to a negative pole of a secondary battery.

Background technique

With energy consumption, the problem of pollution has become increasingly serious. As a power source, new energy vehicles have the advantage of less pressure on the environment. New energy vehicles include pure electric vehicles, extended-range electric vehicles, hybrid vehicles, fuel cell electric vehicles, hydrogen engine vehicles, and other new energy vehicles. Among them, a pure electric vehicle is a vehicle that uses a single battery as an energy storage power source , it uses the battery as the power source for energy storage, provides electric energy to the motor through the battery, drives the motor to run, and thus drives the car, and its technology is relatively simple and mature, with zero emission and zero pollution, which is a current research hotspot. However, the energy stored in the unit weight of the battery is too little, and because the battery of the electric vehicle is more expensive and does not form an economic scale, the purchase price is more expensive; as for the cost of use, some trial results are more expensive than the car, and some results are only 1/ of the car 7~1/3.

Contents of the invention

The purpose of the present invention is to solve the above-mentioned problems and provide a secondary battery that can increase the specific capacity of the battery, especially under the condition of high current density, can still maintain a high specific capacity, thereby improving the charging rate of the battery and the battery life. Secondary battery negative terminal.

The technical scheme that the present invention adopts is as follows:

A secondary battery negative electrode of the present invention comprises a current collector and an active layer covering the surface of the current collector, the active layer has a three-dimensional porous structure, and signal peptides are filled between the pores of the active layer.

Due to the adoption of the above technical solution, the current transmission rate can be enhanced through the signal peptide, and the electrical signal molecule of the signal peptide has a positive response to the transmission of current, thereby increasing the specific capacity of the battery.

A secondary battery negative electrode of the present invention, the characteristic sequence of the signal peptide is: (1) MFAKRFKTSLLAKFAGFLLPLFHLVAKRFGGPLLPLAEN (35).

Due to the adoption of the above technical solution, the characteristic sequence can enable the signal peptide to increase the current transmission rate, thereby increasing the specific capacity of the battery, avoiding the memory effect of the negative electrode, and at the same time improving the ability of the negative electrode material to maintain a high specificity under high current density conditions. capacity.

In the negative electrode of a secondary battery of the present invention, the current collector is a manganous oxide/graphene composite material.

Due to the adoption of the above technical scheme, the negative electrode material has a high specific capacity. At a current density of 100mA·g ^-1 , its specific capacity reaches 870mAh·g ^-1 , but at a current density of 1600mA·g ^-1 , its specific capacity is only is 390 mAh·g ^-1 .

A secondary battery negative electrode of the present invention, the active layer is made of three-dimensional ordered macroporous ceria with mesoporous pore walls, the active layer is bonded to the current collector through an adhesive, and the two The cerium oxide has a pore diameter of 50-200 nm, a pore wall thickness of 15-40 nm, and a diameter of the mesopores of 2-5 nm.

Due to the adoption of the above technical solution, the activation layer can increase the specific surface area of the electrode, thereby increasing the transmission efficiency of the current.

In the negative electrode of a secondary battery of the present invention, the binder is thermoplastic polyimide, and the mass ratio of the binder to the active layer is 1:7.

Due to the adoption of the above technical solution, the current collector has a tensile strength greater than 80N/mm ² .

In the negative electrode of the secondary battery of the present invention, the signal peptide is filled in the pores of the active layer with the electric sensitive hydrogel as the carrier.

A secondary battery negative electrode of the present invention, the electrosensitive hydrogel is 2-acrylamide-2-methylpropanesulfonic acid/N,N-dimethylaminoethyl methacrylate hydrogel, the The molar ratio of 2-acrylamido-2-methylpropanesulfonic acid to N,N-dimethylaminoethyl methacrylate is 15:1.

Due to the adoption of the above technical solution, the hydrogel can enhance the effect of gain on the current sensing of the signal peptide.

In the negative electrode of a secondary battery of the present invention, the mass ratio of the current collector to the active layer is 20:1.

By adopting the above technical scheme, the specific capacity of the electrode can reach 930mAh·g ^-1 at a current density of 100mA·g ^-1 , and the specific capacity can reach 610 mAh·g ^-1 at a current density of 1600mA·g ^-1 , which is comparable to that of Compared with the prior art, it has a great improvement.

In summary, owing to adopting above-mentioned technical scheme, the beneficial effect of the present invention is:

1. It can increase the specific capacity of the battery, especially under the condition of high current density, it can still maintain a high specific capacity, thereby improving the charging rate of the battery and the battery life.

2. At a current density of 100mA·g ^-1 , the specific capacity of the electrode reaches 930mAh·g ^-1 , and at a current density of 1600mA·g ^-1 , its specific capacity can reach 610 mAh·g ^-1 , compared with the prior art has greatly improved.

detailed description

The present invention will be described in detail below.

In order to make the object, technical solution and advantages of the invention clearer, the present invention will be further described in detail below in conjunction with the examples. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

1. Prepare negative electrode current collector material and signal peptide respectively.

The current collector material is prepared by the following steps. Step 1, prepare graphene oxide according to the existing method for subsequent use; Step ₂ , add MnO in an appropriate amount of distilled water at room temperature, and after ultrasonic treatment for 1h, add an appropriate amount of 2mol/L MnO Heat sodium hydroxide solution to adjust the pH of the system to 12, and after heating for 24 hours, centrifuge the suspension to collect the precipitate to obtain Mn ₃ O ₄ ; in step 3, the graphene oxide and the prepared Mn ₃ O ₄ are prepared in a molar ratio of 1:1 Mix evenly, in an argon atmosphere containing 10% hydrogen, and raise the temperature to 500°C at a heating rate of 5°C/min, sinter for 4 hours, and then anneal to obtain a manganese oxide/graphene composite material. The characteristic sequence of the signal peptide is: (1) MFAKRFKTSLLAKFAGFLLPLFHLVAKRFGGPLLPLAEN (35).

2. Prepare the activation layer material by carrying the signal peptide through the hydrogel.

The method of carrying signal peptide on the hydrogel is carried out through the following steps. Step 1: Add appropriate amount of 2-acrylamido-2-methylpropanesulfonic acid and N,N-dimethylaminoethyl methacrylate according to the molar ratio of 15:1 Dissolve in distilled water, and then add ammonium persulfate and sodium bisulfite to the system according to the molar ratio of N,N-dimethylaminoethyl methacrylate: ammonium persulfate: sodium bisulfite 1:1:1; Step 2 , after stirring evenly, inject the mixed solution into a plastic tube with a syringe and seal it. After reacting in a constant temperature water bath at 50°C for 3 hours, add a signal peptide to the plastic tube, and then react in a constant temperature water bath at 32°C for 7 hours; step 3, The hydrogel was taken out of the plastic tube, soaked in deionized water for 3 days, and the water was changed twice a day to remove unreacted monomers and small molecules to obtain a hydrogel carrying a signal peptide.

The activation layer is prepared through the following steps. Step 1 is to synthesize monodisperse PMMA colloidal crystal microspheres with a pore size of 298nm according to the prior art; Dissolve in an appropriate amount of ethanol aqueous solution, where the ethanol content is 40%, stir until dissolved; step 3, put the solution in a porcelain boat, and raise it from room temperature to 300°C at a rate of 1°C/min in an air atmosphere to maintain 3 h, then raised to 500 °C and baked at this temperature for 5 h to obtain a three-dimensional ordered macroporous ceria with mesoporous pore walls; step 4, rapidly cooling to 36 °C and evenly spreading the hydrogel carrying the signal peptide On the surface of ceria, quickly add an appropriate amount of acetonitrile dropwise, and let it stand at 36°C for 30~40min, then wash the surface of ceria with deionized water to obtain an active layer.

3. After the surface of the current collector material is activated, the activation layer is bonded to the current collector material through a binder.

The method for treating the surface of the current collector includes the following steps. In step 1, the surface of the current collector is washed with distilled water for 3 to 5 times, and then dried at 50° C.; in step 2, the current collector is soaked in ten Sodium dialkylbenzenesulfonate aqueous solution, after soaking for 24h, dry.

The bonding of the current collector and the active layer includes the following steps. In step 1, the thermoplastic polyimide is evenly spread on the surface of the treated current collector according to the mass ratio of the active layer to 1:7, and the active layer is covered on the thermoplastic polyimide. Polyimide surface; step 2, connect the current collector to the welding circuit, and bond the current collector and the active layer together by current welding method, the diameter of the welding wire is 0.6, and the current range is 100A.

The prepared secondary battery negative electrode comprises a current collector and an active layer covering the surface of the current collector. The active layer has a three-dimensional porous structure, and signal peptides are filled between the pores of the active layer. The current collector is a manganous oxide/graphene composite material. The active layer is made of three-dimensional ordered macroporous ceria with mesoporous walls. The active layer is bonded to the current collector through an adhesive. The ceria has a pore diameter of 50-200nm and a pore wall thickness of The diameter of the mesopore is 15~40nm, and the diameter of the mesopore is 2~5nm. The signal peptide is carried by the electric sensitive hydrogel and filled in the pores of the active layer. The electrosensitive hydrogel is 2-acrylamido-2-methylpropanesulfonic acid/N,N-dimethylaminoethyl methacrylate hydrogel, the 2-acrylamido-2-methylpropanesulfonic acid The molar ratio of acid to N,N-dimethylaminoethyl methacrylate is 15:1. The mass ratio of current collector to active layer is 20:1.

At a current density of 100mA·g ^-1 , the specific capacity of the electrode reaches 930mAh·g ^-1 , and at a current density of 1600mA·g ^-1 , its specific capacity can reach 610 mAh·g ^-1 , which is extremely superior to the prior art. Big improvement.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (8)

1. a kind of secondary battery negative pole, it is characterised in that：Including collector and the active layer for being overlying on collector surface, the activity Layer has three-dimensional cavernous structure, and signal peptide is filled between the active layer hole.

2. a kind of secondary battery negative pole as described in claim 1, it is characterised in that：The characteristic sequence of the signal peptide is：(1) MFAKRFKTSLLAKFAGFLLPLFHLVAKRFGGPLLPLAEN (35)。

3. a kind of secondary battery negative pole as claimed in claim 2, it is characterised in that：The collector is manganous oxide/graphite Alkene composite.

4. as claimed in claim 2 or claim 3 a kind of secondary battery negative pole, it is characterised in that：The active layer is by with mesoporous hole The three-dimensional ordered macroporous ceria of wall is made, and the active layer is bonding with collector by binding agent, the ceria Aperture is 50 ~ 200nm, and pore wall thickness is 15 ~ 40nm, mesoporous a diameter of 2 ~ 5nm.

5. a kind of secondary battery negative pole as claimed in claim 4, it is characterised in that：Described adhesive is that thermoplasticity polyamides is sub- Amine, described adhesive are 1 with the mass ratio of active layer：7.

6. a kind of secondary battery negative pole as claimed in claim 5, it is characterised in that：The signal peptide is made by electric sensitive aquagel For carrier, it is filled in Jie of active layer Kong.

7. a kind of secondary battery negative pole as claimed in claim 6, it is characterised in that：The electric sensitive aquagel is 2- acryloyls Amido -2- methyl propane sulfonic acids/methacrylic acid N, N- dimethylaminoethyl hydrogels, the 2- acrylamidos -2- methyl-props Sulfonic acid and methacrylic acid N, the mol ratio of N- dimethylaminoethyls is 15：1.

8. a kind of secondary battery negative pole as described in claim 5 or 6 or 7, it is characterised in that：The collector and active layer Mass ratio is 20：1.