Chinese EV Maker Patents Voice-Controlled Toilet Hidden Under Car Seat

Chinese electric vehicle maker Seres has been granted a patent for what it describes as an “in-vehicle toilet”, a fold-out lavatory hidden beneath a passenger seat and activated either manually or by voice command, in a sign of how fiercely carmakers are competing to stand out in China’s crowded EV market. Public reporting on the patent says the command phrase is “start up toilet function”, and the design is intended for long-distance travel, camping and extended stays inside the vehicle.

The patent, identified as CN224104011U, was filed on April 22, 2025, and approved on April 10, 2026, according to reports citing Chinese patent records. The unit slides out from under the seat on rails when needed, then retracts to preserve cabin space when not in use. The filing says the design is meant to “optimize the utility of the car’s interior”, framing the feature as a practical answer to emergencies during long journeys or while stuck on the road.

Reports on the patent say the toilet would include a fan and exhaust pipe to direct odours out of the cabin, along with a waste tank that would need to be emptied manually. A rotating heating element is also described as drying solid waste and evaporating urine, suggesting Seres is trying to solve not just the space problem but also hygiene and smell, the two biggest obstacles to bringing such a feature into a passenger car.

Seres has not announced plans to put the patented system into a production vehicle, and a patent grant does not guarantee commercial launch. Still, the filing has drawn attention because it comes at a time when Chinese EV brands are under pressure to differentiate on technology, comfort and novelty as competition intensifies. Reuters has previously reported that Seres founder Zhang Xinghai described competition in China’s EV market as extremely intense on both price and technology.

The company is no fringe player. Seres is Huawei’s EV partner and the manufacturer behind Aito vehicles, a relationship that has helped it build scale in China’s smart vehicle segment. Reuters reported earlier this year that Aito sold more than 420,000 units in 2025, accounting for the bulk of Seres’ 472,269 EV sales, while the company has also been expanding internationally, including into the Middle East. Seres’ latest annual report says the group sharply increased research spending in 2025, underlining its push for new technologies and premium features.

In-car toilets remain rare in mainstream passenger vehicles, but they are not entirely without precedent. Reports accompanying the Seres patent noted a much older example: a custom 1954 Rolls-Royce Silver Wraith limousine fitted with a concealed toilet under a seat. For now, though, Seres’ invention remains a patent, intriguing enough to spark conversation, but still far from proving whether motorists actually want a bathroom built into the daily commute