HP XP P9500 Owner's Manual page 69

Support to move the batteries to a disk array that is being used, or turn the disk array on to standby
mode for at least 3 hours once every two weeks.
If you store the system for more than two weeks and do not disconnect the cache destage batteries,
when you restart the system, the batteries will need to charge for at least 90 minutes before the
cache will be protected. To prevent the batteries from discharging during long term storage, contact
HP Technical Support and ask them to disconnect the battery jumpers on the cache boards.
Battery backup operations 69