The sandwich-like sulfonated polyimide/chitosan (SPI/CS) composite membranes were prepared and the SDs of the SPI were adjusted from 30 to 70%. Based on the proton/vanadium ion selectivity and chemical stability, the SPI40/CS and SPI50/CS membranes are selected as optimum candidates for all-vanadium redox flow battery (VRFB) applications. The 100-time cyclic charge–discharge testing (50 mA cm−2) results show that the SPI40/CS membrane possessed higher coulombic efficiency than Nafion 117. In addition, the SPI40/CS membrane exhibited more stable energy efficiency than pure SPI40 membrane.
- Xiaodong Huang
- Shuai Zhang
- Xuping Yang
