Abstract :
The stationary lead acid battery is the dominating power reserve for telecommunications by reason of their high reliability which could be demonstrated in the past. Lead acid batteries can easily be recharged, methods for the conservation of the charge are even very simple. The required capacity and number of cells in correspondence to the specified time can easily be calculated. The following requirements should be fulfilled: 1. Full capacity and stable voltage for an extreme long lifetime, 2. effective floating and a minimum loss of water, 3. no passivation effects under charge and discharge conditions, 4. insensibility at increased ambient temperatures, 5. no damage of the battery after a deep discharge, 6. uniformity of single cell voltage and individuel acid densities in all cells, 7. short circuit resistance, 8. maintenancefree for long intervals, 9. minimal requirements for installation and putting into service, 10. safety against explosions, 11. mechanical stability (transportation, installation), 12. indication of the state of charge and the state of aging.
