Lei Jun Explains Xiaomi's 'Sacrifice Wheel, Protect Cabin' Safety Logic

[Technical Analysis] Lei Jun addressed controversy over Xiaomi EVs losing wheels in collisions during a live stream, describing it as a mature 'sacrifice wheel, protect cabin' safety design.

Core Insight: 'Sacrifice Wheel, Protect Cabin' Is Energy Management, Not a Flaw

During his January 3 live stream, Lei Jun disassembled the YU7 to explain that the wheel is designed to detach intentionally during a 25% small-offset collision to prevent the wheel hub from intruding into the passenger compartment. This design uses preset control arm fracture thresholds to sacrifice the wheel and preserve passenger cabin integrity, aligning with the same philosophy as plastic bumpers—'sacrificing the less critical to protect the essential.'

Key Data: No A-Pillar Deformation at 64 km/h Collision

Xiaomi released test footage showing that during a 64 km/h small-offset collision, the vehicle body rebounded and the wheel was ejected outward, yet the A-pillar showed no deformation and the passenger cabin structure remained intact—validating the effectiveness of its passive safety system.

Strategic Foundation: Safety Logic Inherited from Mercedes-Benz and Volvo

Lei Jun clarified that this technology was not originally developed by Xiaomi; Mercedes-Benz implemented a similar approach even earlier than Volvo. This statement both addresses public skepticism and advances broader understanding of automotive passive safety principles.