Lithium iron phosphate (LiFePO4) batteries have received much attention because they can provide higher power density with abundant raw materials, better safety, low toxicity, and high thermal stability. In general, the production of LiFePO4 cathodes uses polyvinylidene fluoride (PVDF) as a binder and N-methyl-2-pyrrolidone (NMP) as a solvent. These components are expensive, toxic, and can adversely affect the environment. Therefore, to address these shortcomings, the solvent and binder were replaced in this study. The solvent in the current study is water. The water soluble binders employed in this study are carboxymethyl cellulose (CMC) and styrene-butadiene rubber (SBR). Suitable electrode formulations were investigated to obtain high performance cylindrical Li-ion batteries. As a result, a formulation with a ratio of LiFePO4:AB:KS6:SBR:CMC equal to 90:3:3:2.677:1.333 was used. It has a high specific discharge capacity, 120 mAh/g. This NMP-based cathode can yield about 145 mAh/g, which is slightly higher than a water-based LiFePO4 cathode.

Lithium-ion batteries have received much attention for their potential use in electric vehicles (EV's) and portable electronic devices. Fabrication of lithium ion (Li-ion) batteries via ecologically sound (green) processes is also of great interest. Typically, in the production of cathode electrodes, organic solvents such as N-methyl-pyrrolidone (NMP) are used, but these chemicals are toxic. Water-based processing of LiNi0.6Mn0.2Co0.2O2 (NMC) for manufacturing cathode electrodes can provide a more environmental friendly option. In this work, water soluble styrene butadiene copolymer (SBR) and carboxymethyl cellulose (CMC) are used as binders. The active material ratio was set at 90%. The electrochemical performance of water-based NMC electrodes is examined. Additionally, various conductive agents were considered including acetylene black (A) and graphite (B). The particle sizes of conductive agent affect the electrochemical performance of the batteries. Our results show that replacing the conventional organic solvent-based manufacturing route for NMC cathodes with a water-based process is a promising way to fabricate Li-ion batteries with comparable electrochemical behavior, while avoiding toxic process materials and simultaneously reducing the overall manufacturing costs.