An environmentally friendly and economic membrane based on cellulose as a gel polymer electrolyte for lithium ion batteries

A green and environmentally friendly polymer, methyl cellulose (MC), is used as a host matrix of a gel polymer electrolyte for lithium ion batteries. It shows good mechanical performance and thermal stability. The ionic conductivity of the gel polymer electrolyte is 0.20 mS cm^-1 and it has a higher lithium ion transference number (t₊ = 0.29) than the commercial separator (0.27). When evaluated using LiFePO₄ as cathode and Li metal as the counter and reference electrode, the LiFePO₄ cathode exhibits relatively higher reversible capacity for the gel polymer electrolyte than that for the commercial separator. In addition, the rate capability and cycling performance are also comparable with those for the commercial separator. This provides another direction for gel polymer electrolytes and environmental protection.