Process suggestions when LA is used in anode materials（for reference only）
Notes：
The electrode composition of lithium-ion battery (formula) is determined by the final requirements of battery performance, the specific operation process is closely related to the physical and chemical properties of the electrode materials that are used, the composition of slurry, the condition of the equipment and the thickness of the electrode etc. So this information has no practical guiding significance and can only be used as a reference document, the example listed in this paper is only used to evaluate the performance of the binder, but not the production instance.
LA aqueous binder has excellent mechanical stability, there’s no demulsification while stirring it for as long as less than 10h under the linear velocity of 18m/s; the appropriate range of PH is 4 to 10, it is applicable to both ordinary and high viscosity slurry preparation process.
The thermal decomposition temperature of LA is no less than 220℃.
1 Formula
a、 C：Super-P：LA=96：1：3
b、 C：Super-P：LA：CMC=96：1：2.5：0.5
c、 C：LA=97 or 96：3.0 or 4.0
d、 C：LA：CMC=97：2.5：0.5
Solvent : water（deionized water, distilled water, pure water）;
Solid content : about 40-50%.
2 Preparation of electrode slurry
2.1 Dispersion of binder
First, add water (distilled water, deionized water or pure water) to the agitate tank, make the solid content of slurry is about 60%, then add LA that is needed, turn on stirring, revolution of 10-20 r/min, rotation of 5-10r/min, stirring for 15-20min; if CMC is needed, refer to the process of SBR/CMC, CMC is configured as solution first and then added into the LA dispersion.
2.2 Dispersion of SP
Add conductive agent to the prepared binder solution, turn on stirring, revolution of 10-20 r/min, stirring for 3-5min,then turn on rotation of 10-20 r/min, stirring for 10-20 min, after the conductive agent is fully wetted, rising the stirring paddle, scrape the drier which stick to the agitate tank wall, bottom and stirring paddle to the tank; after repeating the above process for 1-2 times, dispersing conductive agent under high-speed, revolution of 30-45 r/min, rotation of 25-35 r/min, stirring for 1.0-2.0 h.
2.3 Dispersion of carbon powder
Add carbon powder in batches (according to the amount of powder and the condition of equipment, it can be divided into 2-3 batches to ensure each addition of dry powder can be fully wetted) to the dispersion of binder and conductive agent which has been initially dispersed, after each feeding, turn on stirring, revolution of 15-20 r/min for 3-5min to wet the powder, then turn on the rotation of 15-20 r/min, stirring for 10-20min; rising the stirring paddle, scrape the drier which stick to the agitate tank wall, bottom and stirring paddle to the tank; and then continue stirring for 10-20min, feeding again, repeat the preceding operation.
2.4 Disperse under high-speed
2.5 Viscosity test
Take 250-300mL slurry and test its viscosity at the temperature of 25℃；
The anode viscosity control :about 1500-3500cps at the temperature of 25℃;
Pay special attention: the influence of temperature and humidity to the viscosity while testing.
2.6 Sieving
The slurry can be coated after it through 100-150 mesh screen.
2.7 Instructions
Slurry is also suitable for high viscosity stirring.
3 Coating （example）
4 Instructions
4.1 If LA is placed for more than 2 months, shake well the independent packaging materials that can not use up in onetime before using again.
4.2 Once the packing barrel of LA is opened , cover the inner cap and tighten the barrel cover during later placement, retesting the solid content according to the test methods specified in the product specifications before using it again, and feeding material according to test result.