Advances in electrolyte safety and stability of ion batteries under extreme conditions

Electric vehicles have been promoted worldwide due to fast-charge technology of ion batteries. However, ion batteries’ capacity and cycle life severely decay under extreme conditions, which is mostly related to electrolyte conductivity drop and side reactions. This review highlights the safety and stability of ion batteries in terms of thermal stability, non-flammability, low-temperature, and so on, outlining the disadvantages of organic liquid electrolyte, and summarizing effective solutions of polymer electrolytes, solid-state electrolytes, ionic liquid electrolytes, and aqueous electrolytes for the batteries. Moreover, the outlook on the electrolytes is put forward, which is available for research and development of the next generation batteries.