A coolant management unit for providing liquid cooling for backup battery unit (BBU) modules of an electronic rack includes a BBU return manifold, a BBU supply manifold, a balance loop, and a power bus. For example, a BBU supply manifold having a rack supply connector to receive cooling fluid from a rack supply manifold and a BBU supply connector to be connected to one of the BBU modules to distribute the cooling fluid. A BBU return manifold to be coupled to a rack return manifold, wherein the BBU return manifold is to receive vapor from the BBU modules. A balance loop connected to each of the BBU modules to establish a fluid connection amongst the BBU modules, such that a level of the cooling fluid in each of the BBU modules remains similar.