CN105406081A

CN105406081A - Preparation method for lithium ion battery positive electrode slurry

Info

Publication number: CN105406081A
Application number: CN201510985412.XA
Authority: CN
Inventors: 王海波; 方振华; 吴曲勇
Original assignee: Suzhou Gerui Dynamic Power Technology Co Ltd
Current assignee: Suzhou Gerui Dynamic Power Technology Co Ltd
Priority date: 2015-12-25
Filing date: 2015-12-25
Publication date: 2016-03-16
Also published as: WO2017107806A1

Abstract

The invention discloses a preparation method for lithium ion battery positive electrode slurry. The preparation method comprises the following steps: mixing a positive electrode active substance material, a conductive agent and conductive graphene together based on a certain proportion; performing dry mixing by a dispersion machine; then adding a dispersed graphene glue solution or a carbon nanotube glue solution at a certain proportion, and performing stirring based on programs of a low speed, an intermediate speed and a lower speed for different time; then adding the residual glue solution, and performing stirring based on programs of a low speed, a high speed and a low speed for different time, and then adding NMP for adjusting the viscosity of the slurry; and performing bubble extracting, discharging, coating, pole piece manufacturing and cell manufacturing. According to the preparation method, the dispersing performance of the graphene or the carbon nanotube or other ultra-micro conductive material is improved, so that the capacity and cycling performance of the cell can be effectively improved, and particularly the radiating performance of the battery can be improved so as to improve the safety of the battery.

Description

A kind of preparation method of lithium ion battery anode glue size

Technical field

The present invention relates to a kind of preparation method of lithium ion battery anode glue size.

Background technology

Operating voltage is high owing to having for lithium ion battery, specific energy is large, have extended cycle life, self-discharge rate is low, memory-less effect and the advantage such as environmentally friendly, not only be widely used in the portable sets such as mobile phone, video camera, notebook computer, be also listed in candidate's power supply of electric automobile, space flight, military affairs and large-scale energy storage device.Lithium ion battery is primarily of formations such as positive electrode, negative material, isolated material and electrolyte, and the performance of positive electrode directly affects the property indices of lithium ion battery, in lithium ion battery, occupy core status.Although the market prospects of anode material for lithium-ion batteries are very optimistic, also there is certain technical bottleneck in it, and especially the high advantage strong with security performance of its capacitance does not also give full play of.The capacitance of lithium ion battery, electric conductivity and fail safe can be improved by adding the ultra micro such as Graphene or CNT (carbon nano-tube) electric conducting material in positive electrode.

But these ultra micro electric conducting materials are all difficult to be evenly dispersed in electrode active material, limit giving full play to of its function.The stirring technique of existing anode material for lithium-ion batteries all cannot make ultra micro electric conducting material be disperseed fully.

Summary of the invention

The object of the invention is to overcome the defect existed in prior art, provide a kind of preparation method of lithium ion battery anode glue size, the dispersive property of ultra micro electric conducting material can be improved, and then effectively improve the capacity of battery core, cycle performance and security performance.

For achieving the above object, technical scheme of the present invention comprises the following steps:

1) cathode active material, conductive agent, electrically conductive graphite in (88-95): (1-2): (0-1) ratio (by weight percentage) mixing, be dry mixed with dispersion machine;

2) scattered ultra micro electric conducting material glue is added wherein, can be Graphene glue or CNT (carbon nano-tube) glue, the amount of glue is the 1-3% of positive electrode total amount, first add a part, 0.5-1h is stirred respectively by low speed (being generally 50-100r/min), middling speed (being generally 1000r/min), low speed program, 0.5-2h, 0.5-1h;

3) add remaining described glue, (be generally 1000r/min) by low speed, at a high speed, low speed program stirs 0.5-1h, 1-2h, 0.5-1h respectively;

4) add 1-METHYLPYRROLIDONE (NMP) and adjust slurry viscosity, if cathode active material is cobalt acid lithium, ternary material or LiMn2O4, then viscosity is adjusted to 2000-10000CPS, if cathode active material is phosphoric acid ferrimanganic, then viscosity is adjusted to 8000-12000CPS;

5) take out bubble, discharging, coating, film-making, make battery core;

As preferably, described cathode active material is any one in cobalt acid lithium, ternary material, LiMn2O4, LiFePO4.

Advantage of the present invention and beneficial effect are: the dispersive property effectively improving the micro conductive such as Graphene or CNT (carbon nano-tube) material, effectively can improve capacity, the cycle performance of lithium ion battery cell, the heat dispersion of battery can be improved especially, thus improve the security performance of battery.

Embodiment

Below in conjunction with embodiment, the specific embodiment of the present invention is further described.Following examples only for technical scheme of the present invention is clearly described, and can not limit the scope of the invention with this.

The technical scheme that the present invention specifically implements is:

1) cathode active material, conductive agent, electrically conductive graphite are mixed in the ratio of 92:2:1, be dry mixed with dispersion machine;

2) add scattered Graphene glue wherein, the amount of glue is 3% of positive electrode total amount, first adds a part, under 100r/min condition, stir 0.5h, stirs 1h under 1000r/min condition, stirs 1h under 50r/min condition;

3) add remaining glue, under 100r/min condition, stir 0.5h, under 3000r/min condition, stir 2h, under 50r/min condition, stir 1h;

4) add NMP and adjust slurry viscosity, if cathode active material is cobalt acid lithium, ternary material or LiMn2O4, then viscosity is adjusted to 2000-10000CPS, if cathode active material is phosphoric acid ferrimanganic, then viscosity is adjusted to 8000-12000CPS;

5) take out bubble, discharging, coating, film-making, make battery core.

The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, under the prerequisite not departing from the technology of the present invention principle; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims

1. a preparation method for lithium ion battery anode glue size, is characterized in that, comprises the steps:

1) cathode active material, conductive agent, electrically conductive graphite in (88%-95%): (1-2%): (0-1%) ratio mixing, be dry mixed with dispersion machine;

2) add the scattered ultra micro electric conducting material glue of part wherein, stir 0.5-1h respectively, 0.5-2h, 0.5-1h by low speed, middling speed, low speed program;

3) add remaining described glue, by low speed, at a high speed, low speed program stirs 0.5-1h, 1-2h, 0.5-1h respectively;

4) add NMP and adjust slurry viscosity;

5) take out bubble, discharging, coating, film-making, make battery core.

2. according to the preparation method of the lithium ion battery anode glue size described in claim 1, it is characterized in that, described cathode active material is any one in cobalt acid lithium, ternary material, LiMn2O4, LiFePO4.