Aqueous Slurry For Battery Electrodes

Abstract

A slurry or paste for the manufacture of electrodes for secondary batteries such as lithium ion containing electrochemical cells. The slurry comprises a water based binder with CMC, SBR and PVDF as binder materials.

1 . A slurry for the manufacture of an electrode for an (lithium ion containing) electrochemical cell, the slurry comprising a combination of at least three of polyacrylic acid (PAA), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR) and polyvinylidene fluoride (PVDF) in an aqueous solution and an electrochemically activateable compound. 
     
     
         2 . The slurry of  claim 1 , comprising the polyvinylidene fluoride (PVDF) and at least two of polyacrylic acid (PAA), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR). 
     
     
         3 . The slurry of  claim 1 , further comprising latex in the aqueous solution. 
     
     
         4 . The slurry of  claim 3 , comprising a dispersion of the polyvinylidene fluoride (PVDF) and the latex in the aqueous solution. 
     
     
         5 . The slurry of  claim 1 , wherein in the aqueous solution comprises de-ionized water. 
     
     
         6 . The slurry of  claim 1 , wherein the composition is free of organic solvent. 
     
     
         7 . The slurry of  claim 1 , wherein the concentration of each one of the at least three of the polyacryilic acid (PAA), the carboxymethyl cellulose, the styrene-butadiene rubber and the polyvinylidene fluoride is about 0.5% to about 10% by weight. 
     
     
         8 . The slurry of  claim 1 , wherein the slurry is an electrode slurry of a lithium ion battery. 
     
     
         9 . The slurry of  claim 1 , wherein the electrochemically activateable material comprises at least one of graphite, titanate, lithium metal oxides such as LMO, Li—NCA, LCO, LNCM, LFP and other metal oxides or other materials known in the art, as well as their blends. 
     
     
         10 . A method for the manufacture of an electrode for use in an electrochemical cell, the method comprising:
 preparing a slurry comprising a combination of at least three of polyacylic acid (PAA), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR) and polyvinylidene fluoride (PVDF) as binder in an aqueous solution,   coating or laminating the slurry on a current collector.   
     
     
         11 . The method of  claim 10 , wherein preparing the slurry comprises dispersing latex in the aqueous solution for stabilizing the aqueous solution. 
     
     
         12 . The method of  claim 10 , further comprising adding a non-aqueous electrolyte. 
     
     
         13 . The method of  claim 10 , wherein the concentration of each one of the at least three of the polyacrylic acid (PAA), the carboxymethyl cellulose, the styrene-butadiene rubber and the polyvinylidene fluoride is about 0.5% to about 10% by weight. 
     
     
         14 . The method of  claim 10 , further comprising drying the slurry.