Xiaomi Auto Details Triple Redundancy Safety Design for Pengcheng Door Handles

At the 2026 Chengdu International Auto Show (August 21–30), Xiaomi Auto unveiled details about the safety design behind the door handles on its new Pengcheng N90 Max, emphasizing triple redundancy to ensure doors can be opened during and after severe collisions.

Triple Redundancy for Emergency Access

Xiaomi said the design addresses a critical concern: whether doors can still be unlocked and opened after an extreme collision. The company built three independent fallback paths across three critical stages.

First layer — mechanical external opening. The semi-hidden exterior door handle retains a mechanical override. When a collision meets trigger conditions, the central locking system automatically unlocks, and rescuers outside the vehicle can pull the handle open by hand.

Second layer — redundant backup power for the door lock. Xiaomi acknowledged that severe crashes can disconnect both the vehicle's 12V battery and the high-voltage traction battery. To address this, a dedicated backup power supply is installed beneath the driver's seat, closer to the passenger compartment and therefore less likely to be damaged in a crash. This backup can power the door-lock actuators even when both main power sources are offline.

Third layer — mechanical interior door handle. Inside the cabin, the Pengcheng uses a purely mechanical door handle that does not depend on any electronic control. Passengers can open the door by hand regardless of whether the vehicle has lost all electrical power.

Broader Body Structure Context

The door-handle design sits within a wider passive-safety architecture. The Pengcheng N90 Max features a "armor cage" body structure in which high-strength steel and aluminum account for 90.4 percent of the material mix. The vehicle uses 16 locations of 2,200 MPa ultra-high-strength steel from Xiaomi, an integrated hot-formed door ring spanning all four columns (A through D), an integrated hot-formed front floor skeleton, and a 2,200 MPa "embedded roll-cage" design.

The one-piece hot-formed door ring measures 3,289 mm long and 1,556 mm high, covering all four columns and running through all three rows — a departure from the industry norm of stopping at the C pillar. In simulated side-pole impacts, Xiaomi says the integrated door ring raises the body's lateral load-bearing capacity by 19 percent compared with conventional multi-stamp, resistance-welded designs.

Chengdu Auto Show Lineup

Xiaomi Auto's booth at the Chengdu show (China Western International Expo City, Hall 10, H1004) will feature the Pengcheng N90 Max, N70 Max, SU7, YU7 and SU7 Ultra. The brand also confirmed a patent for a rising/falling exterior emblem that can switch between two designs.