CN102024940A

CN102024940A - Process for producing anode slurry and cathode slurry for lithium ion power battery core

Info

Publication number: CN102024940A
Application number: CN2010105271340A
Authority: CN
Inventors: 李春生
Original assignee: ANHUI ZHONGLING ELECTRIC MOTOR Co Ltd
Current assignee: ANHUI ZHONGLING ELECTRIC MOTOR Co Ltd
Priority date: 2010-10-29
Filing date: 2010-10-29
Publication date: 2011-04-20
Anticipated expiration: 2030-10-29
Also published as: CN102024940B

Abstract

The invention relates to a process for producing anode slurry and cathode slurry for a lithium ion power battery core. When the anode slurry and the cathode slurry are produced, anode and cathode active substances are pretreated and then prepared into the anode slurry and the cathode slurry respectively. The process comprises the following steps of: when the anode slurry is prepared, mixing acetylene black serving as a conductive agent and adhesive, then adding a solvent and the pretreated active substances, and fully stirring the mixture uniformly to produce the anode slurry; and when the cathode slurry is prepared, fully dissolving adhesive into deionized water, adding a solvent, stirring the solution uniformly, adding the pretreated cathode active substance graphite, stirring the solution uniformly, and finally adding neutral vinyltriethoxysilane to produce the cathode slurry. The active substances of a lithium ion power battery produced by using the anode slurry and the cathode slurry have high specific capacity, and high battery capacity still can be kept after multiple times of recycling.

Description

A kind of production technology of electric core of lithium ion power battery positive and negative electrode slurry

Technical field

The present invention relates to lithium battery manufacturing technology field, be specifically related to a kind of production technology of electric core of lithium ion power battery positive and negative electrode slurry.

Background technology

Electric core of lithium ion power battery generally is made up of positive pole, negative pole, diaphragm paper, electrolyte and housing, its manufacture craft at first is after positive and negative pole material is handled, high molecular polymer, inorganic compound and auxiliary material are fully mixed under stirring state, through sieving, make dispersion: amount in accordance with regulations will disperse somaplasm cloth on the template of regulatory specifications then, after roll-in, cut, reel (stacked), the welding, promptly through the aging check; Carry out the charging measurement packing at last.

By the electric core of lithium ion power battery that existing technology is made, the specific capacity of its active material is lower, and after repeatedly recycling, the decline of battery capacity is comparatively obvious, and these deficiencies all await further being improved.

Summary of the invention

The objective of the invention is to deficiency at existing technology for manufacturing electric core of lithium ion power battery, a kind of specific capacity that improves the lithium-ion-power cell active material is provided, and after repeatedly recycling, still can keep the production technology of the electric core of lithium ion power battery positive and negative electrode slurry of higher battery capacity.

The following technical scheme of employing of the present invention:

A kind of collocation method of electric core of lithium ion power battery positive and negative electrode slurry is characterized in that: specifically may further comprise the steps:

(1) preliminary treatment of positive electrode

A, usefulness bolting anode active material of phosphate iron lithium particle, the particle diameter that requires LiFePO4 is 3.6～9um

B, the isolated LiFePO4 of step (a) is dewatered, under the normal pressure, 110-130 ℃ of baking 1.5-2.5 hour;

C, with conductive agent dehydration, require under the normal pressure 190-210 ℃ of baking 1.5-2.5 hour;

D, with binding agent dehydration, 120-140 ℃ of normal pressure baking 1.5-2.5 hour;

(2) negative material preliminary treatment

A, graphite is mixed; ,

B, the graphite that mixes is toasted at normal pressure, remove surperficial oily matter, baking temperature is 300-400 ℃;

C, suitably dilute binding agent with deionized water;

(3) preparation of anode sizing agent

A, be 1 by weight with conductive agent and binding agent: the ratio of (58～62) is fully mixed;

B, solvent is joined in the compound that step (a) mixes, fully mix with the mode that the ultrasonic wave dissolving disperses, the weight ratio of compound and solvent is 1: (14-16);

C, join in the abundant mixed compound of step (b) with conductive agent with through the mixture of the pretreated anode active material of phosphate iron lithium of step (1), after vacuum stirring dissolving evenly, produce anode sizing agent, wherein, carbon black: LiFePO4: solvent three's weight ratio is 3.5: (98-102): (40-50);

Wherein, described conductive agent is an acetylene black; Described binding agent is polyvinylidene fluoride resin (PVDF); Described solvent is a N-methyl pyrrole Lip river alkane ketone;

(4) preparation of cathode size

A, elder generation fully are dissolved in binding agent in the deionized water, add solvent again, stir, and wherein binding agent, deionized water and solvent three's weight ratio is (1-1.5): (42-48): (5.0-5.5);

B, will join in the material that step (a) mixes through the pretreated negative electrode active material graphite of step (2), and stir, wherein the weight ratio of graphite and deionized water is 100: (42-48);

C, neutral vinyltriethoxysilane is joined in the step (b) again, through vacuum stirring evenly after, produce cathode size, wherein, the weight ratio of the negative pole mixed slurry of neutral vinyltriethoxysilane and step (b) is 1: (285-290);

Wherein, described binding agent is sodium carboxymethylcellulose CMC; Described solvent is a styrene-butadiene latex.

The production technology of described electric core of lithium ion power battery positive and negative electrode slurry, it is characterized in that: the described vibrating screen of step is three layers of screen cloth, the ground floor screen cloth sifts out the LiFePO4 particle of particle diameter greater than 9um, and the second layer and the 3rd layer of mesh screen are fallen particle diameter less than the ultra-fine LiFePO4 particle of 3.5um.

Advantage of the present invention:

1, the specific capacity of active material is improved in the anode sizing agent, the present invention is when the anode sizing agent of preparation electric core of lithium ion power battery, mix with conductive agent acetylene black and binding agent earlier, and then add solvent and active material, make the specific capacity of active material bring up to 140mAh/g by original 135mAh/g; And anode active material of phosphate iron lithium after separating treatment tap density be greatly improved, bring up to 1.8-2.0g/cm3 from 1.3g/cm3, thereby have 5～8% to improve the electric core of lithium ion power battery capacity.

2, when the preparation cathode size, add neutral vinyltriethoxysilane, make electric core after repeatedly recycling, still can keep higher capacity.

Embodiment

Below in conjunction with specific embodiment the present invention is described in detail.

1, before the anode sizing agent that is formulated in the preparation electric core of lithium ion power battery of anode sizing agent, with fully separating with vibrating screen (three layers) with the composition of desired 3.6～9um particle diameter of anode active material of phosphate iron lithium, obtain required LiFePO4 more than or equal to the 10um super-size and smaller or equal to the composition of 3.5um ultra-fine grain diameter.

Take by weighing 0.047 gram conductive agent acetylene black and 2.8 gram binding agent polyvinylidene fluoride resins, add then in the 45 gram solvent n methyl pyrrole Lip river alkane ketone, fully mix with the mode that the ultrasonic wave dissolving disperses, the mixture that adds 3.5 gram conductive agent carbon blacks and 100 gram anode active material of phosphate iron lithium again, after vacuum stirring dissolving evenly, produce anode sizing agent.

2, before the cathode size that is formulated in the preparation electric core of lithium ion power battery of cathode size, it is 300-400 ℃ of baking that negative active core-shell material graphite is mixed back temperature under normal pressure, removes surperficial oily matter;

Take by weighing 1.2 gram binding agent sodium carboxymethylcelluloses, fully be dissolved in the 45 gram deionized waters, adding 5.3 gram styrene-butadiene latexes more fully dissolves, add the treated negative electrode active material graphite of 100 grams then, vacuumize stirring until mixing, add neutral vinyltriethoxysilane 0.525 gram then, after vacuum stirring is even, produce cathode size.

Claims

1. the production technology of an electric core of lithium ion power battery positive and negative electrode slurry is characterized in that: specifically may further comprise the steps:

(1) preliminary treatment of positive electrode

A, usefulness bolting anode active material of phosphate iron lithium particle, the particle diameter that requires LiFePO4 is 3.6～9um;

(2) negative material preliminary treatment

A, graphite is mixed; ,

C, suitably dilute binding agent with deionized water;

(3) preparation of anode sizing agent

C, join in the abundant mixed compound of step (b) with conductive agent with through the mixture of the pretreated anode active material of phosphate iron lithium of step (1), after vacuum stirring dissolving evenly, make anode sizing agent, wherein, carbon black: LiFePO4: solvent three's weight ratio is 3.5: (98-102): (40-50);

Wherein, described conductive agent is an acetylene black; Described binding agent is polyvinylidene fluoride resin (PVDF); Described solvent is a N methyl pyrrole Lip river alkane ketone;

(4) preparation of cathode size

A, elder generation fully are dissolved in binding agent in the deionized water, add solvent again, stir, and wherein binding agent, deionized water and solvent three's weight ratio is (3-4.2): (42-48): (5.0-5.5);

C, neutral vinyltriethoxysilane is joined in the step (b) again, through vacuum stirring evenly after, make cathode size, wherein, the weight ratio of the negative pole mixed slurry of neutral vinyltriethoxysilane and step (b) is 1: (285-290);

Wherein, described binding agent is the mixture that polytetrafluoroethylene (PTFE) and sodium carboxymethylcellulose (CMC) mix, and the weight ratio of the two is (1.8-3.0): 1.2; Described solvent is a styrene-butadiene latex.

2. the production technology of electric core of lithium ion power battery positive and negative electrode slurry according to claim 1, it is characterized in that: the described vibrating screen of step is three layers of screen cloth, the ground floor screen cloth sifts out the LiFePO4 particle of particle diameter greater than 9um, and the second layer and the 3rd layer of mesh screen are fallen particle diameter less than the ultra-fine LiFePO4 particle of 3.5um.