Development of Battery Hardware-In-the-Loop System Implemented with Reduced-Order Electrochemistry Li-Ion Battery Models

Aggressive battery usage profiles in electrified vehicle applications require extensive efforts in developing battery management strategy and system design determination to guarantee safe operation under every real-world driving conditions. Experiment based approaches have been widely used for battery system development, but higher costs and longer testing time restrain the number of test cases in the product development process. Battery experiments tend to be conservative to avoid inherent risks of battery failure modes under aggressive battery operation close to the capability limits. Battery Hardware-In-the-Loop (HIL) is an alternative way to overcome the limitations of experiment-based approaches. Battery models in the HIL should provide real-time computation capability and high (at least acceptable) prediction accuracy. Equivalent circuit model (ECM) based HILs have been used owing to their relatively good balance between computational time and prediction accuracy. However, there are difficulties in constructing compact ECM structures to capture reliable battery responses over wide ranges of State of Charge (SOC), current, and temperature. In this study, a new battery HIL platform based on reduced-order electrochemistry Lithium-ion (Li-ion) battery models is developed to overcome the limitations of the ECMs in the HIL platform. Reduced-order electrochemistry battery models show an excellent balance of real-time computation capability and prediction accuracy, and they can be directly implemented in the HIL platform. HIL test results are demonstrated to show their benefits for computational time and prediction accuracy. The developed battery HIL will be used for battery system analysis and battery control development for electrified vehicles.