Is anyone working (or playing :-) ) with LiFePO4 / Lithium Ferro Phosphate batteries. eg A123 cells ex De Walt battery packs or whatever? I'd be interested in thoughts on lifetimes and especially on "calendar life" (as opposed to cycle life) . The technical information on this seems about non existant. It makes sense to expect that it would be much better than standrda LiIon, but how much better is the question. Russell -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist