China’s BYD has unveiled an upgraded version of its Denza Z9 GT, claiming it now offers the longest driving range of any production electric vehicle in the world. The company says the new all-electric grand tourer can travel up to 644 miles on a single charge under China’s CLTC testing cycle, marking a dramatic leap over its predecessor.
The new range figure represents roughly a 64% improvement over the previous Z9 GT, which was rated at 391 miles under the same standard, according to Electrek. Regulatory filings in China list two battery configurations for the updated model: 102.326 kWh and 122.496 kWh packs, delivering between 509 and 644 miles of CLTC range depending on specification.
Interestingly, Denza’s standard Z9 sedan may go even further. Using the same battery options, it is rated for up to 664 miles under CLTC testing, although the company has not formally branded it as the world’s longest-range EV. It is important to note that CLTC figures typically exceed EPA estimates, meaning real-world results in other markets would likely be lower.
The Z9 GT will continue to be offered in both fully electric and plug-in hybrid versions. The updated plug-in hybrid variant receives a 63.82 kWh battery pack, enabling more than 248 miles of all-electric range under CLTC standards, nearly double the previous model’s 125-mile electric range.
Beyond range gains, the new Z9 GT integrates BYD’s next-generation driver assistance platform, branded God’s Eye 5.0. The system supports features such as Navigate on Autopilot for urban and highway use, along with Automatic Emergency Steering that can actively intervene if braking alone may not prevent a collision.
The launch marks a new chapter for Denza, which debuted the Z9 GT in September 2024 as its flagship grand touring model. Founded in 2011 as a joint venture between BYD and Daimler, now Mercedes-Benz, the brand shifted firmly under BYD’s control in 2022 when the Chinese automaker increased its stake to 90%.
With range figures pushing beyond 600 miles on paper, Denza is clearly targeting the top tier of the global EV performance and endurance race.
