Synergetic modulation on solvation structure and electrode interface to achieve lithium-ion batteries cycled at ultra-low temperature

Abstract

The performance of rechargeable lithium-ion batteries (LIBs) in cold environments remains a challenge due to the insufficient ionic conductivity of electrolyte and lithium plating at graphite anodes. Herein, we demonstrate that the synergistic effect of ether-based electrolyte and niobium oxide with high intercalation potential can significantly improve the low-temperature charging/discharging performance of LIBs. Theoretical calculations and in-situ characterizations prove that the weak desolvation energy of electrolyte and the strong binding energy Li+-O bridging coordination synergistically accelerate the interfacial reaction kinetics. The full cells by coupling the niobium oxide anode with LiFePO4 cathode show 95.6% of the initial capacity after 500 cycles at −30 °C, and exhibit excellent rechargeability at −50 °C. This work verifies that the synergism of solvating power of solvent and Li+ intercalation behavior is crucial in low-temperature LIBs.