BYD launches new luxury EV that may adopt solid-state battery technology, boosting range

For luxury EVs, longer range typically comes with a familiar compromise: larger batteries add weight. Solid-state technology could help ease this trade-off, as it can store more energy without requiring heavier battery packs. BYD's upcoming Yangwang luxury sedan brings this possibility into the ultra-luxury car conversation. The vehicle is undergoing testing in China, measuring approximately 5.5 meters (about 18 feet) in length, combining coach doors with an imposing silhouette, and reports suggest it may feature solid-state batteries. BYD has not confirmed the specification.

Although its styling evokes the Rolls-Royce Phantom, the battery question links it to broader development efforts. BMW and Mercedes-Benz are already using electric sedans to investigate how advanced batteries perform outside the laboratory.

Technical advantages of solid-state batteries

What changes inside the battery? The difference starts with the electrolyte, which allows lithium ions to move between electrodes during charging and discharging. Conventional lithium-ion batteries typically use liquid electrolytes, while all-solid-state designs replace them with solid materials. This change can support electrode materials such as lithium metal, potentially increasing the energy stored for a given battery weight. For EVs, this could mean longer range without simply adding battery mass. Mercedes-Benz notes that higher energy density is a key benefit of its solid-state development work.

Safety is another potential advantage. According to the U.S. Department of Energy, solid electrolytes are less prone to leakage when damaged, although the performance of a complete battery still depends on its materials and structure. None of these possibilities have yet determined the Yangwang sedan's range or charging speed. Those figures will require confirmed specifications and testing.

How does Yangwang support BYD's luxury push? Yangwang sits at the top of BYD's lineup, above Denza, showcasing technologies such as the company's four-wheel-drive e4 platform. The upcoming sedan extends this role into the executive segment. Its long wheelbase, boxy silhouette, and coach doors introduce styling associated with established luxury flagships, giving BYD's technological ambitions a more conventional appearance. Yangwang General Manager Hu Xiaoqing described the vehicle as "the culmination of three years of meticulous development by Yangwang, featuring the brand's signature design language, an ultra-luxury executive sedan."

BYD's luxury positioning

This combination signals a strategy built around luxury design and technological differentiation. Solid-state batteries could reinforce this positioning, but whether they will be fitted remains unconfirmed.

What do real-world road tests show? In May 2025, BMW announced that an i7 prototype near Munich is testing Solid Power's all-solid-state battery. Engineers are studying battery expansion, pressure control, and thermal management, with BMW acknowledging that a competitive complete battery system still requires further development. Mercedes-Benz showed another advance in August 2025. An EQS prototype equipped with a Factorial lithium-metal solid-state battery traveled 1,205 kilometers (748.8 miles) without recharging.

Mercedes reported that the battery used delivered 25% more energy compared to a comparable battery pack size and weight. These are development results, not specifications for models available to buyers. The tests demonstrate progress while revealing engineering work that remains. For BYD, the next step is confirming its flagship's powertrain, followed by evidence that the battery can match the luxury experience.