I went to Heeren last Wednesday with 10 fully charged batteries from a week ago. I was told that I needed to charge it a day or 2 before going down, otherwise the test would not be accurate. I was told that it was normal for rechargeables to discharge after 1 week. I was quite surprised as my other rechargeables (besides Sanyo) seem to hold up quite well. I take that to mean that the new Sanyos would discharge after a week. If that's the case, then I would rather throw away the 10 Sanyos and buy another brand rather than going down to change it again.