Power supply device and power supply box thereof

The utility model discloses a power supply device and a power supply box thereof. The power supply box comprises a box body and a box cover matched with the box body. The box body is provided with a hollow inner cavity for mounting the battery module; the box body comprises a bottom wall and a peripheral wall formed by upwards extending the peripheral edge of the bottom wall, and a sealing part is arranged on the inner side of the upper periphery of the peripheral wall; the box cover comprises a top wall and an enclosure bulkhead formed by downwards extending the peripheral edge of the top wall; the power box further comprises a fastener, the fastener penetrates through the surrounding wall and is arranged in the sealing part, so that the box cover and the box body are sealed and fixed, no gap exists between the fastener and the interior of the power box, external media can be effectively prevented from entering the power box, and therefore a battery module or related electronic elements in the power box can