An electrochemical apparatus includes a battery group, a main supply loop, a pre-charging circuit, and a control module. The pre-charging circuit includes a first switch and a thermo-sensitive element. The thermo-sensitive element is configured to electrically connect the first switch, and impedance of the thermo-sensitive element increases with a rise in temperature. The first switch is electrically connected to the control module and the main supply loop, the thermo-sensitive element is electrically connected to the first switch, and the control module is configured to control the first switch to close to turn on the pre-charging circuit. When the pre-charging circuit meets a preset condition, the control module controls the first switch to open to turn off the pre-charging circuit. This application further provides an electrical apparatus, an electric vehicle, and a power supply control method for an electrochemical apparatus.