Exhibit 21 SUBSIDIARIES OF C&D TECHNOLOGIES, INC. C&D Charter Holdings, Inc., incorporated under the laws of the State of Delaware C&D International Investment Holdings, Inc., incorporated under the laws of the State of Delaware C&D Holdings, Ltd., organized under the laws of the United Kingdom NCL Holdings, Ltd., organized under the laws of the United Kingdom C&D Technologies (NCL), Ltd., organized under the laws of the United Kingdom C&D Electronics (Guangzhou) Ltd., organized under the laws of China C&D Instruments, Ltd., organized under the laws of the United Kingdom C&D Components Hong Kong, Ltd., organized under the laws of Hong Kong, China C&D Technology, Ltd., organized under the laws of the United Kingdom C&D Microtek, Ltd., organized under the laws of the United Kingdom Charter Power F.S. Ltd., incorporated in the Islands of Bermuda C&D Technologies (Power Electronics), Ltd., organized under the laws of Ireland C&D Technologies de Mexico, S.A., de C.V., organized under the laws of Sonora, Mexico C&D Technologies (UK) Ltd., organized under the laws of the United Kingdom C&D Technologies (HK) Ltd., organized under the laws of Hong Kong, China C&D Technologies (Italia), S.r.l., organized under the laws of Italy Shanghai C&D Battery Company, Ltd., joint venture organized under the laws of China C&D Technologies Reynosa, S. de R.L. de C.V. organized under the laws of Tamaulipas, Mexico C&D Dynamo Corporation, incorporated under the laws of the state Delaware C&D Power Systems (Canada) ULC, organized under the laws of Canada C&D Technologies (CPS) LLC, organized under the laws of the state of Delaware C&D Technologies (CPS) ULC, organized under the laws of Canada Celab Limited UK, organized under the laws of the United Kingdom Celab Power Management Limited, organized under the laws of the United Kingdom Datel Holding Corporation, organized under the laws of the state of Delaware C&D Technologies (Datel), Inc., organized under the laws of the state of Delaware Datel Systems, Inc., organized under the laws of the state of Massachusetts Datel Kabushiki Kaisya, organized under the laws of Japan C&D Technologies (Datel) GmbH, organized under the laws of Germany Datel SARL, organized under the laws of France Datel (UK) Ltd., organized under the laws of the United States Datel Electronic Technology (Shanghai) Co. Ltd, organized under the laws of China Dynamo Acquisition Corporation, organized under the laws of the state of Delaware