- Yangwang says its U7 retained 98.7% battery capacity after more than 350 flash-charging cycles.
- The manufacturer-run car covered 30,000 km in eight days, 19 hours and 58 minutes.
- Nine days of testing cannot establish how the battery will withstand years of calendar ageing.
A punishing nine-day programme
BYD's premium Yangwang brand says a U7 electric sedan retained 98.7% of its battery capacity after covering 30,000 km and completing more than 350 flash-charging cycles.
Yangwang announced the result on 25 August, describing a manufacturer-run endurance test completed in eight days, 19 hours and 58 minutes. The company says the car was randomly selected from production rather than prepared as a special test vehicle.
The programme was designed to compress an unusually high amount of driving and charging into a very short window. Yangwang says average ambient temperatures exceeded 36 degrees Celsius, with humidity reaching 80%. The U7 was also driven continuously at up to 240 km/h, while its cabin air conditioning was held at 24 degrees Celsius.
After more than 350 charging cycles, the reported 98.7% capacity-retention figure equates to a 1.3% reduction. It is a striking result given the test's intensity, although it comes from Yangwang rather than an independent laboratory.
What the result cannot prove
The distinction between intensive use and long-term ownership matters. This test concentrated distance, heat, high speed and repeated charging into nine days, offering a useful data point on cycling durability under Yangwang's chosen conditions.
It cannot reproduce calendar ageing, which occurs as a battery spends months and years at different temperatures and states of charge. Real-world battery health also depends on charging habits, climate, storage and everyday use, so the result should not be read as a prediction of how every U7 battery will perform over its lifetime.
Yangwang's official model page separately claims the current U7 can charge from 10 to 97% in nine minutes under suitable conditions. Pricing and New Zealand availability have not been disclosed.
