Voltage Fault Precaution and Safety Management of Lithium-ion Batteries Based on Entropy for Electric Vehicles

In operation process of electric vehicles, some factors, such as road conditions, driving habits, vehicle performance always affect batteries performance, which can characterized by batteries voltage to a certain extent. Voltage fault, such as over-voltage or under-voltage will greatly affect the cycle life, state of health and security of lithium-ion batteries. This paper proposed a method of voltage abnormity detection of lithium-ion batteries based on entropy for electric vehicles. The voltage fluctuation data in real time can be obtained by operation service and management center for electric vehicles. The monitoring data was analyzed based on Shannon entropy and sample entropy. The best method of voltage abnormity detection of lithium-ion batteries by using entropy is presented for electric vehicle. The analyzed monitoring data shows that modified Shannon entropy can predict the accurate time and the location of battery or battery pack with voltage fault in advance, so the better security management scheme of the batteries in electric vehicles can be proposed. This method can be used in not only electric vehicles but also in other areas in complex voltage environment.