Two-speed automatic transmission for electric vehicle

The invention relates to a two-speed automatic transmission for an electric vehicle. The two-speed automatic transmission comprises an input shaft, an intermediate shaft, an output shaft, a clutch, a brake, a planetary gear mechanism and a differential mechanism. The intermediate shaft comprises a first end part and a second end part. The output shaft comprises a third end part and a fourth end part. The input shaft is connected with the sun gear of the planetary gear mechanism. The clutch and the brake are detachably connected with the inner gear ring of the planetary gear mechanism. The first end part is connected with the planet carrier of the planetary gear mechanism. The second end part is connected with the third end part. The fourth end part is connected with the differential mechanism. Preferably, the second end part is connected with the third end part and the fourth end part is connected with the differential mechanism in an engaging way through gears. By adopting the two-speed automatic transmission, the invention has the advantages that the requirement of the electric vehicle on the driving motor is reduced, the duration that the driving motor runs in the optimum efficiency region is increased, the power consumption of the driving motor is reduced, the continuous running mileage of the electric vehicle is improved, the design is ingenious, the structure is simple and the two-speed automatic transmission is suitable for large-scale popularization and application.