Lithium Ion Batteries Operated at –100 °C

Abstract

Enabling lithium-ion batteries (LIBs) to operate in a wider temperature range, e.g., as low or high as possible or capable of both, is an urgent need and shared goal. Here we report, for the first time, a low-temperature electrolyte consisting of traditional ethylene carbonate, methyl acetate, butyronitrile solvents, and 1 M LiPF6 salt, attributed to its very low freezing point (T f = −126.3 °C) and high ion conductivity at extremely low temperatures (0.21 mS/cm at −100 °C), successfully extends the service temperature of a practical 9.6 Ah LIB down to −100 °C (49.6% capacity retention compared to that at room temperature), which is the lowest temperature reported for practical cells so far as we know, and is lower than the lowest natural temperature (−89.2 °C) recorded on earth. Meanwhile, the high-temperature performance of lithium-ion batteries is not affected. The capacity retention is 88.2% and 83.4% after 800 cycles at 25 °C and 45 °C, respectively. The progress also makes LIB a proper power supplier for space vehicles in astronautic explorations.