Battery Life; Storing The System - Hitachi G1500 Hardware Manual

Battery life

The batteries have a lifespan of three years and hold a charge for a specific amount time
when disconnected. When the batteries are connected and power is on, the batteries are
continuously charging. The process occurs during both normal system operation and
while the system is in idle mode.
When the batteries are connected and the power is off, the batteries slowly discharge its
power. The batteries have a charge of less than 50% after two weeks without power.
When the batteries are fully discharged, the batteries must be connected to power for
three hours to fully recharge.
Note: The storage system generates a SIM when the cache backup batteries
are not charged to at least 50%. The LEDs on the front panel of the cache
backup kits also show the status of the batteries.

Storing the system

While connected, the cache backup batteries completely discharge in two to three weeks
without power. If you are not using the storage system for two weeks or more, contact
customer support to move the batteries to an active storage system, or set the storage
system to idle mode for at least 3 hours once every two weeks.
If you store the system for more than two weeks without disconnecting the cache
backup batteries, the batteries need to charge for at least 90 minutes when you restart
the system before the cache can be protected. To prevent the batteries from discharging
during long-term storage, contact technical support and request a disconnection of the
battery jumpers on the cache boards.
Hitachi Virtual Storage Platform G1000, G1500, and VSP F1500 Hardware Guide
Chapter 7: VSP G1x00 and F1x00 batteries
Battery life
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