A short Google search yielded: http://www.amazon.com/Battery-Book-One-Traction-Batteries/dp/0939488000 http://www.amazon.com/Valve-Regulated-Lead-Acid-Batteries-J-Rand/dp/0444507469 http://www.amazon.com/Battery-Reference-Book-Third-CROMPTON/dp/075064625X/ ref=sid_dp_dp/102-6581825-8256132 (the latter seems to be the 'bible' - 800 pages ? wow) Peter P. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist