Abstract: A battery pack parallel circuit is connected to a charge/discharge apparatus. The circuit includes a battery module formed by multiple battery packs connected in parallel, and battery packs located at two ends of the battery module are a first end battery pack and a second end battery pack respectively. A positive terminal of the first end battery pack is configured as a positive terminal of the circuit and connected to a positive connection terminal of the charge/discharge apparatus. A negative terminal of the second end battery pack is configured as a negative terminal of the circuit and connected to a negative connection terminal of the charge/discharge apparatus. The connection mode between the battery pack parallel circuit and the charge/discharge apparatus is modified to enable the current to flow in/out from the positive terminal of the parallel battery packs and flow out/in from the farthest negative terminal on the diagonal.