Organic Batteries Operated at −70°C

Low-temperature operation is a great challenge facing rechargeable batteries, and insufficient ionic conductivity and freezing of electrolyte are generally considered as the main reasons for this issue. Herein, an ethyl acetate-based electrolyte with a sufficient ionic conductivity of 0.2 mS cm−1 at the ultra-low temperature of −70°C is first used to fabricate intercalation compounds-based Li-ion batteries (LIBs) and an organic electrodes-based rechargeable battery, respectively, to clarify their low-temperature behavior. It is demonstrated that the LIBs cannot work at −70°C because of the sluggish desolvation of Li+. However, the rechargeable battery using organic electrodes can work well at such low temperature and retains ∼70% of capacity at room temperature, owing to the fast kinetics of charge storage on the surface groups or in the large interstitial space of organic solids. These results indicate a new way for developing low-temperature batteries.