Cascading contactor drive system

Abstract

A system for sequentially interconnecting battery modules of a battery pack is disclosed. The battery pack may comprise first, second and third battery modules. Each of the first, second and third battery modules includes a first power output terminal and a second power output terminal. Each of the first power output terminals is of a first polarity and the each of the second power output terminals is of a second, opposite polarity. The system comprises a control module for providing a control signal to sequentially interconnect the battery modules, a first interconnect controller electrically disposed between the first and second battery modules, and a second interconnect controller electrically disposed between the second and third battery modules. Each of the first and second interconnect controllers includes a contactor comprising a main contact, an auxiliary contact and an actuating coil for closing the respective main contact and auxiliary contact. The actuating coil of the first interconnect controller responds to the control signal to close the respective main contact, coupling the first battery module to the second battery module, and to close the respective auxiliary contact to pass the control signal to the second interconnect controller. The actuating coil of the second interconnect controller responds to the passed control signal from the first interconnect controller to close the respective main contact of the second interconnect controller, coupling the third battery module to the previously connected first and second battery modules.