BYD executives have defended the company’s flash charging technology following concerns over battery temperatures during ultra-fast charging tests.
Sun Huajun, chief technology officer of BYD’s battery business group, said advances in battery materials, thermal management and electrochemical systems have overcome traditional limitations associated with high-speed charging.
In comments published by Chinese media outlet 36Kr following the 2026 Beijing Auto Show, Sun said concerns about battery degradation from ultra-fast charging were based on outdated assumptions.
“We cannot simply look at new technologies using our past experiences, habits, and inertial thinking,” Sun said.
BYD introduced its second-generation Blade Battery and flash charging technology on March 5.
The system supports charging power levels of up to 1,500 kilowatts and is designed to charge a vehicle battery from 10% to 97% in approximately nine minutes.
The company has also emphasized the system’s low-temperature charging performance, stating that charging times at minus 30 degrees Celsius increase by only around three minutes compared with room-temperature operation.
The technology was prominently displayed at BYD’s exhibition area during the Beijing Auto Show earlier this month.
Questions surrounding the technology intensified after a Chinese automotive blogger published test results showing battery cell temperatures reaching 70 degrees Celsius during flash charging sessions.
Sun acknowledged that high-current charging naturally generates additional heat but argued that elevated temperatures no longer necessarily imply safety risks or structural damage for lithium iron phosphate batteries.
“Seventy degrees Celsius is only a cognitive boundary of the past,” Sun said.
He added that the industry had previously believed LFP batteries could not safely exceed 60 degrees Celsius before advances in cooling systems and battery chemistry changed those assumptions.
According to Sun, BYD conducted extensive durability and reliability testing before deploying the technology commercially.
“We did a massive amount of cycle and reliability testing before turning it into a technology that can be installed in vehicles on a large scale,” he said.
The company said testing included 1,000 full flash-charging cycles and long-term degradation simulations under extreme operating conditions.
BYD plans to build 20,000 flash charging stations across China by the end of 2026, targeting coverage within five kilometres for 90% of urban areas.
Sun said the technology raises technical barriers within the battery industry because it requires advanced expertise in electrochemistry and systems engineering to achieve full battery charging within 10 minutes.
Since March, BYD has expanded adoption of the flash charging platform across several models, including the recently launched Denza N9 flash charging edition under its Denza brand.