I bought 2 pairs of rechargeable AA Nimh batteries in September and have used them around 8 times since. The batteries are now showing end of life signs. They start to get discharged within 10 mins of use and also if i charged them and kept, the battery totally lost its charge while idle within 2 days. What happened? I m angry as i didnt think i would need to buy recharegeable batteries so frequently and with such liitle use. Please help.