The challenge of producing lithium-ion batteries meeting performance requirements and low environ- mental 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 TiO2 anodes by optimizing the elec- trode manufacturing process in terms of composition and compression. The stability and the high rate performances of the TiO2/CMC are described and compared with those of TiO2/PVDF electrodes. The compatibility of the TiO2/CMC with a LiFePO4 cathode in a full-cell is also reported.
High performance, environmentally friendly and low cost anodes for lithium-ion battery based on TiO2 anatase and water soluble binder carboxymethyl cellulose
NOBILI, Francesco;TOSSICI, Roberto;MARASSI, Roberto
2011-01-01
Abstract
The challenge of producing lithium-ion batteries meeting performance requirements and low environ- mental 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 TiO2 anodes by optimizing the elec- trode manufacturing process in terms of composition and compression. The stability and the high rate performances of the TiO2/CMC are described and compared with those of TiO2/PVDF electrodes. The compatibility of the TiO2/CMC with a LiFePO4 cathode in a full-cell is also reported.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
