Improved Elevated Temperature Performance of LiFePO4/Graphite Cell by Blending NMC640 in Cathode

Abstract

Physical mixtures of LiMn2O4 (LMO) and NMC active cathode materials is a well-known strategy in commercial batteries to achieve better cycling and storage performance than cells with a pure LMO cathode. In this work, we demonstrated a similar synergic effect in LiFePO4(LFP)/NMC640 cathode material blends. Blending LFP with NMC640 in the weight ratio of 90% to 10% lead to improvements in cycling and storage compared to cells with LFP alone. A clear linear coordination between capacity loss and iron deposition on the graphite anode was observed in these blended cells. This work shows that blending NMC in LFP cathode is a promising strategy to improve the high-temperature stability of LFP/graphite cells for long-term operation.