Reconditioning backup batteries—the right way
- Instant availability of supply power to the critical load via the UPS in the event of sags, spikes, complete utility failure, or any other power disturbance that requires a switchover to a backup power source
- Proper sizing to supply the critical load that is normally supported by the utility via the UPS
- Sufficient operating time for backup power to come online (typically the time required for a generator to start and be able to accept load).
- Maintaining the NiCd cell at a fixed floating voltage for a period of time
- Storing a battery for long periods of time without proper activation
- Applying an improper commissioning charge.
- Discharging the cells as a string to 1.1 V per cell at 211 A for 5 hr
- Recharging the cells as a string at 1.62 V per cell for 30 hr
- Allowing the cells to remain on open circuit for 4 hr before discharge
- Discharging the cells as a string at 456 A to 1.15 V per cell.
Jennifer A. Eirich is a marketing manager, Utilities/Rail at EnerSys. She joined EnerSys in 2012 as part of the team responsible for launching the company’s first utility-scale energy optimization system. Eirich has more than a decade of experience in mixing and systems engineering. She is a member of the U.S. Technical Advisory Group to IEC TC120 for the Standardization of Electrical Energy Storage Systems. Eirich holds a BS in Chemical Engineering from Pennsylvania State University.