阅读说明：本技术 一种三维锂离子电池的制备方法 (Preparation method of three-dimensional lithium ion battery ) 是由 闫小舍 邱扬 康书文 于 2018-06-22 设计创作，主要内容包括：一种三维锂离子电池的制备方法,用于锂离子电池制造。将混合均匀的正极导电胶液、负极导电胶液分别涂布于三维箔材的一侧,烘干即得到正极导电胶膜和负极导电胶膜,再将正极浆料、负极浆料分别涂布于正极导电胶膜、负极导电胶膜上,制备成三维锂离子电池。本发明的导电胶膜粘结性和导电性良好,可以有效防止在使用三维箔材涂布过程中漏料、掉料等问题,降低电池制造成本,同时可有效提高三维锂离子电池的充放电效率、能量密度、循环性能和倍率性能。(A preparation method of a three-dimensional lithium ion battery is used for manufacturing the lithium ion battery. Respectively coating the uniformly mixed positive conductive glue solution and negative conductive glue solution on one side of the three-dimensional foil, drying to obtain a positive conductive adhesive film and a negative conductive adhesive film, and respectively coating the positive slurry and the negative slurry on the positive conductive adhesive film and the negative conductive adhesive film to prepare the three-dimensional lithium ion battery. The conductive adhesive film disclosed by the invention is good in cohesiveness and conductivity, can effectively prevent the problems of material leakage, material falling and the like in the process of coating by using a three-dimensional foil material, reduces the manufacturing cost of the battery, and can effectively improve the charge-discharge efficiency, the energy density, the cycle performance and the rate capability of the three-dimensional lithium ion battery.)

1. A preparation method of a three-dimensional lithium ion battery is characterized by comprising the following steps: the preparation method comprises the following steps:

(a) respectively preparing positive conductive glue solution and negative conductive glue solution;

(b) uniformly coating the positive conductive glue solution on one side of a three-dimensional foil, drying the three-dimensional foil by using an oven to prepare a positive conductive glue film, uniformly coating the negative conductive glue solution on one side of the three-dimensional foil, and drying the three-dimensional foil by using the oven to prepare a negative conductive glue film, wherein the coating thickness of the positive conductive glue solution and the negative conductive glue solution is 0.2 ~ 50 mu m, and the temperature of the oven is 60 ~ 130 ℃;

(c) preparing positive electrode slurry and negative electrode slurry;

(d) uniformly coating the positive electrode slurry on the surface of a positive electrode conductive adhesive film, drying the positive electrode slurry by using an oven, uniformly coating the positive electrode slurry on one side or two sides of a three-dimensional foil according to needs, and drying the positive electrode slurry by using the oven to obtain a positive electrode plate, uniformly coating the negative electrode slurry on the surface of a negative electrode conductive adhesive film, drying the negative electrode slurry by using the oven, uniformly coating the negative electrode slurry on one side or two sides of the three-dimensional foil according to needs, and drying the negative electrode plate by using the oven to obtain a negative electrode plate, wherein the coating thickness is 5 ~ 1000 mu m, and the temperature of the oven is 60 ~ 130 ℃;

(e) respectively carrying out rolling, slicing, assembling, baking, injecting, forming and grading on the prepared positive plate and the prepared negative plate to prepare a lithium ion battery or a lithium ion button battery; the lithium ion battery comprises a positive plate, a negative plate, a diaphragm, electrolyte, a battery shell and a lug; the lithium ion button cell comprises a pole piece, a lithium piece, a diaphragm, electrolyte and a cell shell.

2. The preparation method of the three-dimensional lithium ion battery according to claim 1, wherein the positive conductive glue solution comprises a conductive agent, a solvent and a binder, the mass ratio of the conductive agent to the binder is (0.1 ~ 20): 1, the solid content of the positive conductive glue solution is 1% ~ 40%, the negative conductive glue solution comprises a conductive agent, a solvent and a binder, the mass ratio of the conductive agent to the binder is (0.1 ~ 20): 1, and the solid content of the negative conductive glue solution is 1% ~ 40%.

3. The method of claim 1, wherein the three-dimensional foil is one of aluminum, copper, iron, tin and stainless steel, the thickness of the foil is 5 ~ 30 μm, the porosity of the foil is 10% ~ 80%, and the pore size of the foil is 0.1 ~ 300 μm.

4. The method for preparing the three-dimensional lithium ion battery according to claim 1, wherein the anode slurry comprises an anode active material, a conductive agent, a binder and a solvent, the anode active material content is 80% ~ 98%, the conductive agent content is 0.5 ~ 10%, the binder content is 1 ~ 10%, and the slurry solid content is 30% ~ 80%, and the cathode slurry comprises a cathode active material, a conductive agent, a binder and a solvent, the cathode active material content is 80% ~ 98%, the conductive agent content is 0.5 ~ 10%, the binder content is 1 ~ 10%, and the slurry solid content is 30% ~ 80%.

5. The method according to claim 1, wherein the method comprises the following steps: the conductive agent comprises one or more of conductive carbon black, acetylene black, Ketjen black, conductive graphite, carbon nano tubes and graphene.

6. The method according to claim 1, wherein the method comprises the following steps: the binder comprises one or more of sodium carboxymethylcellulose (CMC), Styrene Butadiene Rubber (SBR), acrylonitrile multipolymer (LA 132, LA 133), Polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF).

7. The method according to claim 1, wherein the method comprises the following steps: the solvent includes one of deionized water and N-methylpyrrolidone (NMP).

8. The method according to claim 4, wherein the method comprises the following steps: the positive active material is one or more of lithium iron phosphate, lithium vanadium phosphate, lithium cobaltate, lithium manganate, lithium nickel cobalt manganate and lithium nickel cobalt aluminate; the negative active material is one or more of artificial graphite, natural graphite, mesocarbon microbeads, silicon monoxide and silicon-carbon composite materials.

Technical Field

The invention relates to the technical field of lithium ion battery manufacturing, in particular to a preparation method of a three-dimensional lithium ion battery.

Background

In recent years, lithium ion batteries have been widely used in the fields of small portable electrical appliances such as notebook computers, mobile phones and digital cameras, aerospace, electric vehicles and the like due to their advantages of high energy density, high voltage, no memory effect, low self-discharge rate and the like. With the development of a new generation of electric vehicles and hybrid electric vehicles, the nation strongly supports the research, development, production and sale of lithium ion batteries, and puts higher requirements on the energy density of the lithium ion batteries.

Compared with the traditional two-dimensional flat plate foil, the three-dimensional foil is characterized in that a large number of micron-sized through holes are prepared on the surfaces of aluminum foil and copper foil, and the three-dimensional foil is used as a current collector, so that the conductive interface of an active substance can be greatly increased, the interface resistance is reduced, the performance of the active substance can be fully exerted, and the three-dimensional foil has very important significance in the aspects of improving the energy density and safety performance of a battery, reducing the manufacturing cost of the battery and the like. The improvement of the porosity of the three-dimensional foil can increase the coating amount of the electrode material, and meanwhile, the electrolyte can fully permeate through the micropores on two sides of the base material, so that the infiltration of the electrolyte in the battery is improved, the polarization of the battery cell is reduced, and the battery performance can be obviously improved in the aspects of circulation, multiplying power, internal resistance and the like.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a preparation method of a three-dimensional lithium ion battery, which aims to solve the problems of material leakage, material falling and the like in the process of preparing the three-dimensional lithium ion battery.

In order to achieve the above object, the preparation method of the present invention comprises the following steps:

(a) respectively preparing positive conductive glue solution and negative conductive glue solution;

(b) uniformly coating the positive conductive glue solution on one side of a three-dimensional foil, drying the three-dimensional foil by using an oven to prepare a positive conductive glue film, uniformly coating the negative conductive glue solution on one side of the three-dimensional foil, and drying the three-dimensional foil by using the oven to prepare a negative conductive glue film, wherein the coating thickness of the positive conductive glue solution and the negative conductive glue solution is 0.2 ~ 50 mu m, and the temperature of the oven is 60 ~ 130 ℃;

(c) preparing positive electrode slurry and negative electrode slurry;

(d) uniformly coating the positive electrode slurry on the surface of a positive electrode conductive adhesive film, drying the positive electrode slurry by using an oven, uniformly coating the positive electrode slurry on one side or two sides of a three-dimensional foil according to needs, and drying the positive electrode slurry by using the oven to obtain a positive electrode plate, uniformly coating the negative electrode slurry on the surface of a negative electrode conductive adhesive film, drying the negative electrode slurry by using the oven, uniformly coating the negative electrode slurry on one side or two sides of the three-dimensional foil according to needs, and drying the negative electrode plate by using the oven to obtain a negative electrode plate, wherein the coating thickness is 5 ~ 1000 mu m, and the temperature of the oven is 60 ~ 130 ℃;

(e) respectively carrying out rolling, slicing, assembling, baking, injecting, forming and grading on the prepared positive plate and the prepared negative plate to prepare a lithium ion battery or a lithium ion button battery; the lithium ion battery comprises a positive plate, a negative plate, a diaphragm, electrolyte, a battery shell and a lug; the lithium ion button cell comprises a pole piece, a lithium piece, a diaphragm, electrolyte and a cell shell.

The positive conductive glue solution comprises a conductive agent, a solvent and a binder, the mass ratio of the conductive agent to the binder is (0.1 ~ 20): 1, the solid content of the positive conductive glue solution is 1% ~ 40%, the negative conductive glue solution comprises the conductive agent, the solvent and the binder, the mass ratio of the conductive agent to the binder is (0.1 ~ 20): 1, and the solid content of the negative conductive glue solution is 1% ~ 40%.

The three-dimensional foil is one of aluminum, copper, iron, tin and stainless steel, the thickness of the foil is 5 ~ 30 mu m, the porosity of the foil is 10% ~ 80%, and the aperture of the foil is 0.1 ~ 300 mu m.

The anode slurry comprises an anode active substance, a conductive agent, a binder and a solvent, wherein the content of the anode active substance is 80% ~ 98%, the content of the conductive agent is 0.5 ~ 10%, the content of the binder is 1 ~ 10%, the solid content of the slurry is 30% ~ 80%, the cathode slurry comprises a cathode active substance, a conductive agent, a binder and a solvent, the content of the cathode active substance is 80% ~ 98%, the content of the conductive agent is 0.5 ~ 10%, the content of the binder is 1 ~ 10%, and the solid content of the slurry is 30% ~ 80%.

The conductive agent comprises one or more of conductive carbon black, acetylene black, Ketjen black, conductive graphite, carbon nano tubes and graphene.

The binder comprises one or more of sodium carboxymethylcellulose (CMC), Styrene Butadiene Rubber (SBR), acrylonitrile multipolymer (LA 132, LA 133), Polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF).

The solvent includes one of deionized water and N-methylpyrrolidone (NMP).

The positive active material is one or more of lithium iron phosphate, lithium vanadium phosphate, lithium cobaltate, lithium manganate, lithium nickel cobalt manganate and lithium nickel cobalt aluminate; the negative active material is one or more of artificial graphite, natural graphite, mesocarbon microbeads, silicon monoxide and silicon-carbon composite materials.

Compared with the prior art, the invention has the following advantages:

(1) the conductive adhesive film in the preparation process of the three-dimensional lithium ion battery has good cohesiveness, can solve the problems of material leakage, material falling and the like when the three-dimensional porous foil is used for coating, avoids material waste, reduces the preparation cost, and improves the energy density, the cycle performance and the rate capability of the lithium ion battery.

(2) The conductive adhesive film in the preparation process of the three-dimensional lithium ion battery has good conductivity, and the conductive agent contained in the conductive adhesive film can play a role in collecting micro-current between the active substances and the current collector so as to reduce the contact resistance of the electrode and accelerate the moving speed of electrons. In addition, the conductive adhesive film and the three-dimensional foil act together, so that the pole piece can be soaked by the electrolyte, the migration rate of lithium ions in the electrode material can be effectively improved, the polarization is reduced, the charge-discharge efficiency is improved, and the service life of the lithium ion battery is prolonged.

Detailed Description

The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention as described. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions. The reagents and starting materials used in the following examples are commercially available.

The preparation method comprises the following steps:

(a) respectively preparing positive conductive glue solution and negative conductive glue solution;

(b) uniformly coating the positive conductive glue solution on one side of a three-dimensional foil, drying the three-dimensional foil by using an oven to prepare a positive conductive glue film, uniformly coating the negative conductive glue solution on one side of the three-dimensional foil, and drying the three-dimensional foil by using the oven to prepare a negative conductive glue film, wherein the coating thickness of the positive conductive glue solution and the negative conductive glue solution is 0.2 ~ 50 mu m, and the temperature of the oven is 60 ~ 130 ℃;

(c) preparing positive electrode slurry and negative electrode slurry;

(d) uniformly coating the positive electrode slurry on the surface of a positive electrode conductive adhesive film, drying the positive electrode slurry by using an oven, uniformly coating the positive electrode slurry on one side or two sides of a three-dimensional foil according to needs, and drying the positive electrode slurry by using the oven to obtain a positive electrode plate, uniformly coating the negative electrode slurry on the surface of a negative electrode conductive adhesive film, drying the negative electrode slurry by using the oven, uniformly coating the negative electrode slurry on one side or two sides of the three-dimensional foil according to needs, and drying the negative electrode plate by using the oven to obtain a negative electrode plate, wherein the coating thickness is 5 ~ 1000 mu m, and the temperature of the oven is 60 ~ 130 ℃;

(e) respectively carrying out rolling, slicing, assembling, baking, injecting, forming and grading on the prepared positive plate and the prepared negative plate to prepare a lithium ion battery or a lithium ion button battery; the lithium ion battery comprises a positive plate, a negative plate, a diaphragm, electrolyte, a battery shell and a lug; the lithium ion button cell comprises a pole piece, a lithium piece, a diaphragm, electrolyte and a cell shell.

The positive conductive glue solution comprises a conductive agent, a solvent and a binder, the mass ratio of the conductive agent to the binder is (0.1 ~ 20): 1, the solid content of the positive conductive glue solution is 1% ~ 40%, the negative conductive glue solution comprises the conductive agent, the solvent and the binder, the mass ratio of the conductive agent to the binder is (0.1 ~ 20): 1, and the solid content of the negative conductive glue solution is 1% ~ 40%.

The three-dimensional foil is one of aluminum, copper, iron, tin and stainless steel, the thickness of the foil is 5 ~ 30 mu m, the porosity of the foil is 10% ~ 80%, and the aperture of the foil is 0.1 ~ 300 mu m.

The anode slurry comprises an anode active substance, a conductive agent, a binder and a solvent, wherein the content of the anode active substance is 80% ~ 98%, the content of the conductive agent is 0.5 ~ 10%, the content of the binder is 1 ~ 10%, the solid content of the slurry is 30% ~ 80%, the cathode slurry comprises a cathode active substance, a conductive agent, a binder and a solvent, the content of the cathode active substance is 80% ~ 98%, the content of the conductive agent is 0.5 ~ 10%, the content of the binder is 1 ~ 10%, and the solid content of the slurry is 30% ~ 80%.

The conductive agent comprises one or more of conductive carbon black, acetylene black, Ketjen black, conductive graphite, carbon nano tubes and graphene.

The binder comprises one or more of sodium carboxymethylcellulose (CMC), Styrene Butadiene Rubber (SBR), acrylonitrile multipolymer (LA 132, LA 133), Polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF).

The solvent includes one of deionized water and N-methylpyrrolidone (NMP).

The positive active material is one or more of lithium iron phosphate, lithium vanadium phosphate, lithium cobaltate, lithium manganate, lithium nickel cobalt manganate and lithium nickel cobalt aluminate; the negative active material is one or more of artificial graphite, natural graphite, mesocarbon microbeads, silicon monoxide and silicon-carbon composite materials.