Electric vehicle braking energy recovery device and method and electric vehicle

The invention relates to an electric vehicle braking energy recovery device and method and an electric vehicle. The electric vehicle braking energy recovery device comprises a multi-gear switch (1), and a vehicle control unit; the multi-gear switch (1) is provided with at least two gears and is configured to select different load working conditions of a vehicle by receiving external operation, andthe at least two gears are in one-to-one correspondence with different load working condition levels, wherein different load working conditions correspond to different load intervals; and the vehiclecontrol unit (3) is electrically connected with the multi-gear switch (1) and is configured to conduct matching according to the corresponding relation between the load working condition selected bythe multi-gear switch (1) and preset working condition-brake feedback parameters so as to obtain the brake feedback parameters of the vehicle under the current load working condition and enable the vehicle to perform brake ener