Perc battery shown as missing

dell-percdell-poweredgelsimegaraid

I replaced a failed battery in a Perc 5/i. The original and replacements are the same DLU8735 model. I couldn't find any special battery replacement procedures in the manual, so I just turned the system off and swapped them. After installing the replacement battery, GetBbuStatus started showing the battery as missing. GetBbuCapacityInfo showed it as charging, so I though perhaps this needed to complete before the battery would be used. However, it is now 100% charged yet still reported as missing. I thought perhaps I need to force a learn cycle, but this completes instantly with no change in status. The system is out of warranty, so I can't call Dell. Any ideas for why this battery is seen yet not used?

lspci | grep RAID

02:0e.0 RAID bus controller: Dell PowerEdge Expandable RAID controller 5

MegaCli64 -AdpBbuCmd -BbuLearn -aALL

Adapter 0: BBU Learn Succeeded.

Exit Code: 0x00

MegaCli64 -AdpBbuCmd -GetBbuStatus -aALL

 BBU status for Adapter: 0

 BatteryType: No Battery
 Battery State: Missing

 Exit Code: 0x00

MegaCli64 -AdpBbuCmd -GetBbuCapacityInfo -aALL

 BBU Capacity Info for Adapter: 0

   Relative State of Charge: 100 %
   Absolute State of charge: 100 %
   Remaining Capacity: 1897 mAh
   Full Charge Capacity: 1900 mAh
   Run time to empty: Battery is not being charged.  
   Average time to empty: Battery is not being charged.  
   Estimated Time to full recharge: Battery is not being charged.  
   Cycle Count: 0
 Max Error = 0 %
 Remaining Capacity Alarm = 190 mAh
 Remining Time Alarm = 10 Min

 Exit Code: 0x00

MegaCli64 -AdpBbuCmd -GetBbuDesignInfo -aALL

 BBU Design Info for Adapter: 0

   Date of Manufacture: 11/15, 2007
   Design Capacity: 1900 mAh
   Design Voltage: 3700 mV
   Specification Info: 49
   Serial Number: 4471
   Pack Stat Configuration: 0xe4bc
   Manufacture Name: SANYO
   Firmware Version   : 
   Device Name: DLU8735
   Device Chemistry: LION
   Battery FRU: N/A
   Transparent Learn = 0
   App Data = 0

 Exit Code: 0x00

MegaCli64 -AdpBbuCmd -GetBbuProperties -aALL

 BBU Properties for Adapter: 0

   Auto Learn Period: 90 Days
   Next Learn time: Sat Jan  1 00:00:00 2000
   Learn Delay Interval:0 Hours
   Auto-Learn Mode: Enabled

 Exit Code: 0x00

Best Answer

Sounds like you have a bad connection. Others have reported success after blowing out the RAID battery plug and socket with compressed air.

If that doesn't work, you will need to try replacing the PERC 5/i (which in early 2014 costs less than $20 in good used condition) and/or trying another battery.