Patent ID: 9692044
Date: 2017-06-27
CPC Classifications: H01M,Y02E,Y02P

Claim:
1. A process for preparing a rechargeable battery comprising a positive electrode, a negative electrode and an electrolyte, comprising: providing a battery container, a current collector and a separator, providing a positive electrode, providing an electrolyte comprising an SEI-film forming agent, wherein the SEI film-forming agent is selected from one or more of the group consisting of fluoro ethylene carbonate, vinylidene carbonate, vinyl ethylene carbonate, phenyl ethylene carbonate, phenylvinylene carbonate, catechol carbonate, allyl methyl carbonate, allyl ethyl carbonate, vinyl acetate, acrylonitrile and 2-cyanofuran, providing a negative electrode comprising a micrometric Si based active material having a particle size distribution with 1 μm<D50<15 μm and with 1 μm<D80<15 μm, a polymeric binder material having carboxyl functional groups and a conductive agent, wherein at least part of a surface of the Si based active material comprises a Si—OCO—R group, Si being part of the active material, and R being a polymeric chain of the binder material, and assembling the current collector, the separator, the electrolyte, the positive electrode and the negative electrode in the battery container to prepare the rechargeable battery.