The invention provides a battery cooling system, a vehicle power exchange system and a battery cooling control method. The battery cooling system comprises a cooling liquid loop, a bypass branch and acontrol module, wherein the cooling liquid loop comprises a cold supply source, a liquid storage container, a power source and a plurality of battery cooling branches, the cold supply source, the liquid storage container and the power source are connected, the plurality of battery cooling branches are connected in parallel, a rechargeable battery is connected to the battery cooling branches underan application state, a first end of the bypass branch is connected with the cooling liquid loop between a downstream of the power source and an upstream of the battery cooling branches, a second endof the bypass branch is connected with the cooling liquid loop between a downstream of the battery cooling branches and an upstream of the power source, the bypass branch is controllably conducted ordisconnected, at least one part of cooling liquid passes through the bypass branch in a condition state, and the control module is used for maintaining pressure difference between an inlet and an outlet of each battery cooling branch within a preset zone by controlling on or off of the bypass branch. By the battery cooling system, the vehicle power exchange system and the battery cooling controlmethod, the battery cooling system can be maintained to stably work, and the rechargeable battery obtains a stable cooling effect.