Sodium Carboxymethyl Cellulose

The electrochemical performance of negative electrodes based on commercially available crystalline Si powder and sodium carboxymethyl cellulose (CMC) binder was investigated. Compared to the conventional binder, polyvinylidene fluoride, Si electrodes using CMC binder show vastly improved cycling performance. A high specific capacity of about for has been achieved with a lower cutoff potential of vs . Si electrodes made using CMC binder have better capacity retention than those using a binder consisting of CMC and styrene butadiene rubber. CMC is an extremely stiff and brittle polymer, so it is surprising that it functions well as a binder in electrodes where the volume change of the active material particles is about 100%.