| abstract |
The invention relates to electrically conductive adhesion promoters for electrodes, primarily for lithium-ion batteries. DOLLAR A Known adhesion promoters have serious disadvantages in the adhesion of active anode materials based on carbon capable of intercalation or of active cathode materials based on transition metal oxides with intercalated Li in the adhesion to copper or aluminum current collectors. DOLLAR A The adhesion promoter generally causes the above materials to adhere to one another (intra effect) as well as to the adhesion to the current collector (extra effect). DOLLAR A The adhesion or binding of the transition metal oxides or the carbons should meet the following conditions: DOLLAR A 1. an adhesion on the current collector that is stable even over longer cycles> 200 cycles, d. H. shows no detachment and DOLLAR A 2. is so stable that mechanical loads such as kinking or pressure do not lead to cracks, detachments or displacements from the current collector. DOLLAR A The adhesion promoter is a polymer that is completely indifferent to the processes and ion exchange reaction in the battery system and fulfills the requirements for "intra or extra effect" and is electrically conductive. DOLLAR A Suitable polymers according to the invention are polyvinylpyrrolidone homo- and / or copolymers which are listed in the BASF brochure "PVP and more" (MER 9709d). The homopolymers have molecular weights from 10,000 to 25,000, the copolymers have molecular weights from 25,000 to 2,000,000. As comonomers, ... |