Influence of Coolant Properties on Battery Thermal Management in Electric Buses during Cold Starts

<div>Improving electric vehicles’ overall thermal management strategy can directly or indirectly improve battery efficiency and vehicle range [<span>1</span>].</div> <div>In this study, the effect of the coolant type used in BTMS (battery thermal management system) units used for heating batteries in cold weather conditions was investigated in electric buses. In this investigation, tests were performed with two types of antifreeze, which have different characteristics. The study evaluated the impact of coolant flow, BTMS circulation pump performance, and battery heating using these two types of antifreeze in the BTMS coolant line. In addition to carrying out tests, 1D computational fluid dynamics models’ simulations were carried out for both types of antifreeze, and the results were validated with experimental findings.</div> <div>In this study, a 12-m EV Citivolt vehicle of Anadolu Isuzu was used for tests.</div> <div>As a result, it was observed that differences in the properties of the antifreeze that is used in BTMS coolant line affected the coolant flow and BTMS heating performance in cold weather conditions.</div>