Backup Battery Unit Charge Time for Intel® RAID Controllers
When a backup battery unit (BBU) for an Intel® RAID Controller is first installed, it needs some time to charge before it becomes fully operational. During this time, you may see POST errors. Although it may be a given, to protect your data, Intel recommends setting the Intel® RAID Controller Write Policy to Write-Through until the battery unit is fully charged. Depending on the firmware level on the Intel® RAID Controller, the battery status during charging may be reported as bad or missing, or alternatively as charging or defective.
If the battery has only been installed in the system for a short time, do not be concerned. Older firmware levels report the battery as bad or missing, unless it is fully charged. Later firmware reports the battery as charging or defective, unless it is fully charged.
Likewise, if the Intel® Server System with the battery installed experiences a loss of power, and the battery is depleted during the power failure, it recharges after the main power comes back. As the battery is charging, the POST again reports the battery as bad or missing or as charging or defective.
Battery charging times vary, but the typical charging time is 24–48 hours.
If your battery is still giving POST errors that it is bad or missing or that it is charging or defective after 72 hours charging time, contact Intel Customer Support.