Liquid-gas heat transfer characteristics of near isothermal compressed air energy storage based on Spray Injection

•Liquid-gas heat transfer of I-CAES based on spray injection was analyzed.•Spray effectively suppresses air temperature change due to high heat transfer rate.•Spray flow rate determines the dominant heat transfer mechanism.•Slow compression/expansion with enough heat transfer duration leads to high RTE.•High air storage pressure deviates CAES from isothermal system leads to low RTE.