Abstract: An apparatus for charging electric storage batteries comprises a host computer for providing charging information to and receiving status information from a plurality of slave computers. The slave computers are coupled to the host computer by means of a fiber optic data link. A plurality of control modules are coupled to each slave computer. Each control module applies charging current to a plurality of electric storage batteries in response to instructions received from the slave computer. Each control module also sends charging and battery temperature status information back to its respective slave computer.