BYD claims 98.7% capacity after 30,000 km test

In Nanning, a Yangwang U7 has been driving for nearly nine days when its odometer reaches 30,000 km. The production sedan drove in average temperatures above 36 °C, with humidity of up to 80% and an announced cruising speed of 240 km/h. At the end of the marathon organized by BYD, its battery still showed 98.7% of its initial capacity.

The charging pace was as unusual as the distance. In 8 days, 19 hours and 58 minutes, the car underwent more than 350 fast charges. This schedule compressed into a few days the kind of demands a driver would generally spread over several years, while also putting the powertrain and battery cooling system to the test.

The battery in question is the Blade 2.0, a new generation installed for the first time in the 2026 Yangwang U7. The automaker reports a loss limited to 1.3% after the test. The figure therefore describes the remaining capacity of this particular vehicle after an extreme sequence, not a battery-aging guarantee for every car.

So what does it mean in practice? If other teams reproduce the measurement, drivers could gain a reassuring indication of a battery’s resistance to repeated fast charging. For heavily used fleets, the result would be particularly interesting: it directly concerns the available capacity after many cycles. But no independent test has yet been published to confirm the significance of this performance.

BYD controlled the protocol itself and says the car was chosen at random from a dealership. Yangwang’s general manager says she is open to independent verification. The automaker may also be sending a signal to Beijing ahead of January 1, 2027, when new electrified vehicles sold in China will have to undergo validation tests covering at least 30,000 km.