Why don't the rear wheels of electric vehicles use disc brakes?

Due to the relatively high configuration and complex structure of disc brakes, the cost of disc brakes for electric vehicles is relatively increased. Disc brake is also called hydraulic brake or hydraulic brake; Drum brake is a traditional braking method of friction deceleration between brake pad and wheel drum. Generally, the front wheels of vehicles in the market use disc brakes and the rear wheels use drum brakes, which is called "front disc and rear drum" configuration. The rear wheels don't need disc brakes because of the cost, and many of them are front and rear disc brakes. In the failure rate of automobile brakes, the failure rate of front brakes is different from that of rear brakes, and the failure rate of rear brakes will be higher.

Advantages of disc brake:

Disc brake has the characteristics of fast heat dissipation, light weight, rapid braking and convenient adjustment. It also has good high temperature resistance under high load, stable braking effect and little influence by external environmental factors. In addition, the disc brake is caliper-type, and the brake shoe and the brake disc are in plane contact, with large contact surface and rapid braking, which is suitable for frequent braking and generally does not need adjustment. Drum brake pads and brake drums are in curved contact, from point to surface, so the braking efficiency is relatively low.