Controlling cabin heating to improve range and battery lifetime of electric vehicles

Short range remains a major disadvantage of battery electric vehicles compared to vehicles that have combustion engines. Range reductions also result from low ambient temperatures and from battery aging. By varying power of the heating system depending on the highly fluctuating propulsion power and using electrothermal recuperation, range losses can be minimized. This paper focuses on the development and comparison of strategies to control the vehicle's heating circuit. Rule-based, fuzzy logic, and optimization-based strategies are designed and implemented in a validated BMW i3 simulation model. The results show that fuzzy logic leads to the greatest improvement of range and battery lifetime. Compared to the standard strategy, range can be increased by 14% at -10 degrees C and by 6.5% at 0 degrees C. The current throughput during recuperation is reduced the most by a rule-based strategy that prioritizes the heater. For discharging, fuzzy logic can reduce the current throughput by a maximum of 11%, which leads to a capacity fade reduction of 4.3%. Since air mass is controlled separately, the cabin temperature remains almost constant, thus maintaining the comfort of the user. (c) 2022 Published by Elsevier B.V.

Automated summary

Short range remains a major disadvantage for battery electric vehicles compared to combustion engine vehicles. This paper focuses on the development and comparison of strategies to control the vehicle's heating circuit in order to minimize range losses. The results show that fuzzy logic leads to the greatest improvement in range and battery lifetime.