Abusive discharges to zero volt of VRLA/AGM monoblocs in 24 V strings

Lead acid batteries may experience an abusive "deep"discharge condition when more than 100% of the nominal capacity is withdrawn. This paper describes the behavior of a VRLA/AGM battery under such discharge conditions by examining temperature and voltage parameters. As results show, certain designs of VRLA/AGM batteries exhibit a good tolerance against such abusive conditions. A discharge for a period of 130 h below 1.80 Vpc did not induce, after recharge at the float voltage of 2.25 Vpc, any capacity loss in such a battery.