I've been unhappy with the lifespan of the 18v Milwaukee batteries. Compared to my Makita batteries, the Milwaukees last only half as long or less, before they won't take a charge anymore.Too bad, because I really like the 18v Milwaukee circular saw and the 18v Hatchet recip saw. Rather than purchase new batteries from Milwaukee, I'm going to try having the old ones rebuilt and see if that improves their performance.