High performance, environmentally friendly and low cost anodes for lithium-ion battery based on TiO_2 anatase and water soluble binder carboxymethyl cellulose

摘要

The challenge of producing lithium-ion batteries meeting performance requirements and low environmental impact is strictly related to the choice of materials as well as to the manufacturing processes. Most electrodes are currently prepared using poly(vinilydene fluoride) (PVDF) as binder. This fluorinated polymer is expensive and requires the use of a volatile and toxic organic solvent such as N-methyl-pyrrolidone (NMP) in the processing. Water soluble sodium carboxymethyl cellulose (CMC) can be a suitable substitute for PVDF as binder for both anodes and cathodes eliminating the necessity of NMP and thus decreasing the cost and the environmental impact of battery production. In this work, CMC has been successfully used to prepare efficient and stable anatase TiO_2 anodes by optimizing the electrode manufacturing process in terms of composition and compression. The stability and the high rate performances of the TiO_2/CMC are described and compared with those of TiC^/PVDF electrodes. The compatibility of the TiO_2/CMC with a LiFePO_4 cathode in a full-cell is also reported.