Research progress, challenges and prospects of fault diagnosis on battery system of electric vehicles

Due to the limited capacity and voltage of single battery cell, the battery system for electric vehicles often consists of hundreds or thousands of single cells in series and parallel connection. The inconsistency of individual cell in capacity, voltage, internal resistance, etc., and their coupling effects with aging make the battery system fail frequently, which brings great challenges to the safe and reliable operation of the battery system. This paper discusses the research progress of battery system faults and diagnosis from sensors, battery and components, and actuators: (1) the causes and influences of sensor fault, actuator fault, internal/external short circuit fault, overcharge/over-discharge fault, connection fault, inconsistency, insulation fault, thermal management system fault are analyzed; (2) the fault diagnosis methods and their application characteristics in up-to-date battery system fault research are discussed, and the research trends of battery system fault diagnosis are sorted out; (3) Further, the future challenges and potential research directions of battery system fault diagnosis driven by new technologies such as big data are discussed. Finally, the summarization of whole paper is presented.