EXHIBIT 21 SUBSIDIARIES OF C&D TECHNOLOGIES, INC. C&D/Charter Holdings, Inc., incorporated in the state of Delaware Ratelco Electronics, Inc., incorporated in the state of Delaware Charter Power F.S. Ltd., incorporated in the Islands of Bermuda Power Convertibles Corporation Ireland Ltd., organized under the laws of Ireland PCC Mexican Holdings, Inc., a Delaware corporation PCC de Mexico, S.A. de C.V., organized under the laws of Sonora, Mexico C&D TECHNOLOGIES de Mexico, S.A., de C.V., organized under the laws of Sonora, Mexico C&D Acquisition Corp., a Delaware corporation C&D Technologies (U.K.) Ltd., organized under the laws of the United Kingdom