(Yicai Global) March 14 -- Chinese new energy vehicle manufacturers WM Motor and Xpeng Motors have recently received complaints about their cars’ charging capacity and mileage after the over-the-air upgrade.

Car owners aired their grievances on the complaint resolution platform Black Cat, moaning that their cars’ charging capacity dropped and corresponding mileage shrank after the OTA upgrade.

Zhang Qi, a user of a WM Motor vehicle, revealed that a group set up to safeguard the legitimate rights of car owners now has 600-plus members.

In January, more than 170 car owners sent attorney’s letters to the Shanghai-based EV maker, stating that WM’s unilateral limitation of charging capacity of users’ vehicles led to a sharp decline in corresponding mileage, Zhang revealed.

But WM Motor told Yicai Global that the company had not limited the charging capacity. However, it added the mileage of NEVs will be reduced a bit in winter. As of March 8, WM Motor had received a total of 247 calls asking about the mileage, and it has invited car owners to its sales stores to help them better understand the status of their vehicles, the firm stated.

A number of Xpeng car owners also complained on Black Cat, claiming that the first batch of 670 Xpeng P7 models encountered charging capacity limit for no reason and an 80.3-kilowatt-hour capacity battery could only be charged to around 70kwh.

Responding to the claims, Xpeng’s customer service staff insisted that there were no charging capacity restrictions.

Industry analyst Zhang Xiang said that although fast-charging technology is swift, it can lead to overcharging and spontaneous combustion accidents. So “locking power or limiting the charging capacity” can reduce overcharging by restricting the charging power while at the same time ensuring relatively fast charging speed.

However, the automakers have not specifically informed car users about the impacts and effects brought by such limitation during relevant OTA or offline upgrades. Regulatory bodies, therefore, should introduce relevant rules, requiring carmakers to tell vehicle owners about the upgrade content and impact, Zhang added.

Editors: Zhang Yushuo, Peter Thomas