The current research of battery energy storage system (BESS) fault is fragmentary, which is one of the reasons for low accuracy of fault warning and diagnosis in monitoring and controlling system of BES. ••We review the possible faults occurred in battery energy storage system.••. The development of renewable energy generation, distributed energy supply and electrification on customer side provide a stage for the rapid development of energy storage technolo. 2.1. Hierarchy and components of BESSBESS uses battery as energy storage carrier to store and release recyclable electric energy, which includes LIBs, electrical compo. 3.1. Thermal abuseThermal abuse refers to the continuous overheating of LIB by an external heat source, resulting in thermal runaway. The fault evolution m. 4.1. Unwelded connectorsBattery packs are usually connected with metal joints. If the connection joints were loose, it would cause the increase of contact resistanc.