Xiaomi Corp.'s promotion of its YU7 electric vehicle's range performance has sparked controversy after a prominent automotive reviewer questioned the validity of a winter test conducted at temperatures critics say were too mild to qualify as genuine cold-weather conditions.

Lei Jun, Xiaomi's founder, chairman and CEO, shared data from Autohome showing the YU7 achieved 687 kilometers of range in Beijing at 10 degrees Celsius, ranking first in both total range and achievement rate among tested vehicles. The results were presented as winter testing performance.

The claims drew immediate pushback from Chen Zhen, a well-known automotive reviewer, who disputed the characterization of the test as winter conditions. The controversy highlights growing scrutiny of electric vehicle range claims as automakers compete intensely in China's crowded EV market.

Chen questioned whether testing at 10 degrees Celsius constitutes meaningful winter evaluation, noting the methodology could mislead consumers about real-world cold-weather performance.

Test Methodology Challenged

Chen Zhen characterized the assessment as "a regular three-car range comparison test" organized by Autohome rather than authentic winter testing. He argued that labeling the evaluation as "winter testing" or "quasi-winter testing" could mislead consumers about the vehicle's performance in genuinely cold conditions.

The reviewer emphasized that 10 degrees Celsius falls short of temperatures where electric vehicles typically experience significant range degradation, questioning the appropriateness of applying winter testing terminology to the results.

Battery Technology Context

Chen pointed to the battery chemistry used in the tested vehicles as further evidence the conditions were insufficient for meaningful winter evaluation. All three vehicles in the comparison utilized lithium iron phosphate batteries, which theoretically only experience range degradation at temperatures between 0 and minus 10 degrees Celsius.

This technical detail underscores the gap between the actual test conditions and the temperatures at which consumers would expect to see winter-specific performance impacts on electric vehicle range.

The incident reflects broader challenges facing automakers as they market electric vehicles in markets with varying climates, where range anxiety remains a significant consumer concern and testing standards continue to evolve.