On 7th August 2007, I had purchased an Exide tubular battery IT 500 from ROYAL BATTERY HOUSE IRINJALAKUDA, KERALA state for Rs. 10500. The dealer has given 30 months replacement guarantee. About 2 months back I noticed it is not giving the rated capacity of 150 ampere hours. Dealer representative came, examined the battery and said it is not getting fully charged by the invertor to the specified 13.8 volts. Invertor mechanic has now adjusted the cut off voltage to 13.8 volts but still there is no improvement in the battery performance. With a connected load of 120 watts (1 fan & 1 tube light ) the battery gets drained out in one hour. I have connected a + / - ammeter in series with the battery and I am able to monitor the charge / discharge current . Battery capacity appears to have degraded to less than 50 AH even though it has worked for only 17 months. I would be grateful if you look into this problem and do the needful.