Low-temperature and high-rate-charging lithium metal batteries enabled by an electrochemically active monolayer-regulated interface

Abstract

Stable operation of rechargeable lithium-based batteries at low temperatures is important for cold-climate applications, but is plagued by dendritic Li plating and unstable solid–electrolyte interphase (SEI). Here, we report on high-performance Li metal batteries under low-temperature and high-rate-charging conditions. The high performance is achieved by using a self-assembled monolayer of electrochemically active molecules on current collectors that regulates the nanostructure and composition of the SEI and deposition morphology of Li metal anodes. A multilayer SEI that contains a lithium fluoride-rich inner phase and amorphous outer layer effectively seals the Li surface, in contrast to the conventional SEI, which is non-passive at low temperatures. Consequently, galvanic Li corrosion and self-discharge are suppressed, stable Li deposition is achieved from −60 °C to 45 °C, and a Li | LiCoO2 cell with a capacity of 2.0 mAh cm−2 displays a 200-cycle life at −15 °C with a recharge time of 45 min. In addition to high energy, batteries need to possess high power and to be able to operate in all climates. Here, the authors present an electrochemically active monolayer-coated current collector that is used to produce high-performance Li metal batteries under low-temperature and high-rate-charging conditions.