My PL-330 generally runs for several days (perhaps 2-3 hours each day) playing at medium volume. I find the BL-5C 3.7 Volt Li-ion batteries have a long life for their size. I have them in several radios and have so far had no problems with them, some of them after several years. I'm still a little leery of all rechargeable batteries of unknown sources but it seems hard to avoid them nowadays.
