As we are facing more frigid and frosty weather during 2020/21 winter, more concerns have been focused on issues of battery performance and mileage of electric vehicle. The low-temperature performance of 9 Chinese popular electric vehicles has been compared from EV-Test evaluation results, to help customers alleviate range anxiety.
CATARC EV-Test evaluates the EV driving range test under China Light-Duty Vehicle Test Cycle (CLTC) considering both normal weather and cold weather, which are characterized as 23°C and -7°C respectively. For the cold-weather test of driving range and charging performance, all vehicles shall be frozen in an environmental chamber at -7°C for 14-16 hours firstly, and the cabin temperature should be maintained by car heater to around 20 - 22°C during driving test.
1. Analysis of the mileage range based on CLTC
Under above simulated cold conditions, electric vehicle range fluctuates extremely and suffered an average loss of 40% range. BYD Qin Pro EV shows the least mileage loss of 26% among 9 EV models. Based on CLTC, the average EV range of 9 EVs was around 426 miles at 23°C and drops to 261 miles at -7°C.
2. Comparison of the accuracy of mileage range estimation
The accurate prediction of range for electric vehicles is also crucial in reducing range anxiety. EV-Test recorded the displayed remaining range and the actual driving range, and evaluates the accuracy of range estimation by a statistical method called "coefficient of determination R². The closer R² is to 1, the more accurate the mileage estimation will be.
3. Analysis of the charging speed
EVs charge more slowly in winter because the battery’s ability to accept a charge is reduced. EV-Test compared the DC charging time from empty to 80% of SoC (State of Charge) in normal environment with the charging time in simulated cold weather. For 9 tested EV models, the average increase rate of charging time caused by cold was about 40%, and no unusual interruption of charging occurred during the low temperature test.
4. Research and test capability
Learn more about CATARC EV-Test (now has been integrated in China Automotive Consumer Research and Testing Regulation, CCRT): http://ccrt.xn--fiqs8s/
