Aqueous processing based novel composite electrode for Li-ion batteries using an environmentally benign binder
Along with the high energy density and safer battery materials, easy and environment benign electrode processing is also one of the major concerns for the battery manufacturing industries. Therefore, herein, water-based electrode processing is used which reduces manufacturing cost and makes easy and cost-effective recycling of discarded batteries. In addition, the increasing use of Li-ion batteries from portable electronics to electric vehicles has imposed a threat to the environment due to hazardous materials used. The present study also focuses on the replacement of polyvinylidene difluoride (PVDF) non-conducting binder dissolves in toxic solvent N-methyl 2-pyrrolidone with water-soluble poly (3,4-ethylene dioxythiophene): poly (styrene sulfonate) (PEDOT:PSS) conducting binder. The entire study is performed on the synergistic effect of PEDOT: PSS with multi-walled carbon nanotubes (MWCNTs or MC) and carbon black (CB) on Li-ion battery performance using LiFePO4 cathode active material. The discharge capacities were found 144 mAh g−1 and 160 mAh g−1 at 0.1C for composite electrodes LFP/CB-9P and LFP/MC-9P, respectively having 9 wt% PEDOT: PSS. Whereas the composite electrodes LFP/CB-10PV and LFP/MC-10PV having 10 wt% PVDF binder show only capacities 117 mAh g−1 and 134 mAh g−1, respectively. The composite electrode LFP/MC-9P shows the highest capacities up to 20C rate and maximum retention capacity of 84% at 5C after 500 cycles among all samples studied. Whereas electrodes prepared with PVDF binder could not perform well at more than 5C current rate, capacity retention is also found nearly 0% after 500 cycles. Therefore, superior results of PEDOT: PSS and MWCNTs with LiFePO4 propose an environmentally benign composite electrode of next generation Li-ion batteries for electric vehicles.