Dell PowerVault MD3000 BAT-1S3P Replacement Battery 2.5V 6600mAh

Dell PowerVault MD3000 — 2.5V Li-ion Replacement Battery (BAT-1S3P)

This is a 2.5V Li-ion battery rated at 6600mAh (16.5Wh), fitting the Dell PowerVault MD3000 and MD3000i RAID storage arrays. It backs up the RAID controller cache during a power loss event, holding cached write data long enough for the controller to flush or preserve it safely. OEM part numbers BAT-1S3P, JY200, C291H, P16353-06-C, and 371-2482 all cross to this cell.

• MD3000 and MD3000i controller fit: Both the MD3000 and MD3000i share the same RAID controller battery bay, connector pinout, and BMS communication protocol — one cell covers both enclosures without modification.
• Bench tested on actual hardware: We cycled this battery through full charge and discharge on an MD3000 controller. The BMS handshake completed correctly, the controller recognised the cell, and write-back mode activated after the learn cycle finished.
• Learn cycle initiation after swap: After seating this battery, trigger the learn cycle manually from the PERC management interface or Dell MD Storage Manager — the controller will not exit write-through mode until it recalibrates the backup window estimate against the new cell's actual capacity.

RAID controller staying in write-through mode after battery swap

Write-through mode is not a fault — it is the controller protecting your data while it has no confirmed backup window. After a battery replacement, the controller does not automatically trust the new cell until a learn cycle runs and completes. On the MD3000, initiate the learn cycle through Dell MD Storage Manager or via the PERC CLI. Until that cycle finishes, all writes bypass the cache and go directly to disk, which cuts write throughput significantly.

Management console reporting a battery error days after installation

The MD3000 controller runs its battery health assessment on a timed schedule — not at boot and not immediately after a swap. If the scheduled assessment fires before the learn cycle has fully recalibrated the cell, the controller logs a battery error even on a fully functional replacement. This is not a fault with the cell itself. Let the learn cycle complete first (typically 24–72 hours under normal array load), then check MD Storage Manager again — the error clears once the controller has a valid backup window figure.