China’s New Luxury EV Claims World’s Longest Range—Is It True?

Two years ago at Auto China, electric carmaker BYD showed off the Denza Z9 GT, a luxurious model with a shooting brake body style. Denza was formed as a luxury branch of BYD in a joint venture with Mercedes-Benz, although the German company has since reduced its stake in Denza. The Z9 GT is one of the models to come from Denza’s restructuring, and it has just achieved an impressive feat, if proven: This is now the EV with the longest range on a full charge. Denza claims it can cover a remarkable 1,036 kilometers or around 644 miles between charges, although that figure does come with one major caveat.

CLTC Vs. EPA Range: Not Nearly The Same Thing

Denza’s 644-mile range claim is based on the China Light Duty Vehicle Test Cycle, or CLTC. According to Green Cars Compare, the CLTC test cycle typically results in much more optimistic claims, while the EPA test cycle used in the U.S. is more closely correlated with real-world range. CLTC range estimates can be around 30% higher than the EPA’s. Using this difference, the Denza Z9 GT—which has a maximum battery size of 122.5 kWh—would have an EPA rating of about 451 miles.

That would place it well behind the Lucid Air Grand Touring, which has a 512-mile EPA range on 19-inch wheels. Of course, we can only draw a definitive conclusion if both cars were tested under identical conditions.

According to China-based publication CnEVPost, the Z9 sedan will have an even longer CLTC range of 1,068 km/663 miles. That would place the EPA rating at around 470 miles, assuming it’s 30% lower than the CLTC figure.

Even if the “longest EV range in the world” claim is dubious, the Z9 EVs are impressive machines that display China’s growing prominence and technological expertise in the auto industry. They have a long range, advanced LiDAR sensors, a Crab Walk function (allowing for sideways parking in tight spots), and three electric motors producing up to 952 horsepower.

What It Means

Until—and if—Chinese EVs are ever sold here and assessed by the EPA, the debate about what the longest-range EV actually is will continue. In the United States, that car remains the Lucid Air Grand Touring. Vastly different testing cycles make direct comparisons impossible, as some have lower average speeds than others or feature more or less acceleration/braking events.

Perhaps the more relevant question is whether EVs with over 500 miles of range matter at all. A 2025 study showed that EV owners already aren’t using more than 80% of their vehicles’ range, indicating that the more common 300 miles or so are sufficient.

In the current climate, charging speeds and accessible infrastructure may be more crucial than chasing longer ranges with ever-bigger battery packs.