By mixing this binders to the electrolyte powder to produce uniform in thickness and produce green strength of the pellet.we are using only powders not solutions because the electrolyte is moisture problems.also tell me the procedure to follow this mixing process and what temperatures we have to maintain.
Could you explain it further. For what application and material?
If it is for batteries, why to mix electrolyte powders with binders?
Do you mean solvent, not electrolyte? PVDF dissolved in NMP is probably most common. I have also seen PTFE used in literature, but I have never successfully made a solution with NMP. The other binder I commonly see is CMC (carboxymethly cellulose, sodium salt) with water as the solvent. However, since it is water soluble you cannot use it for aqueous electrolytes. Also if your electrode material is water sensitive then you can't use water as the binder solvent. Also when using CMC/water, I first clean the electrode current collector with 0.1 M oxalic acid solution, this helps the binder solution wet the surface, otherwise a good film will not be made.
As for the procedure, we prepare a binder/solvent solution first, I have been using 20 mg/ml concentration. The electrode powder is mixed with carbon with mortar and pestle (this is important, I do this for about 30 minutes). Then add the binder/solvent solution to the dry powder and mix with mortar and pestle, or take the dry powder and add it with binder solution in a sample vial to be ultrasonicated with ultrasonic probe several times. I have seen other methods of mixing binder with powder in literature, such as stirring overnight. When the electrode slurry is ready, deposit it on your current collector and doctor blade it. There are some tools to help doctor blading, but if you don't have them you could just use tape as railings and doctor blade with a glass rod on top of the tape. The concentration of binder solution and time spent mixing or sitting on current collector before doctor blading is important, it can affect your film thickness and quality. It will probably take many trials to achieve what you are looking for.
Thank you ram.yes we used in batteries.to achieve uniform in size and green strength and to with stand the temperatures above 400oC.we used licl and kcl in this which binder is used for to achieve our goal and the binder is must be inorganic compund.we didn't mix any water.
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