Dell PowerEdge 1750 RAID Controller Compatible Battery 6V 57DHN

Dell PowerEdge 1750 / 2500 Series — 6V Ni-MH RAID Controller Battery (57DHN)

This is a 6V 1500mAh Ni-MH replacement battery for the RAID controller backup power system in Dell PowerEdge 1750, 2500, 2500c, and 2550 servers. It provides temporary power to the RAID controller cache during unexpected power loss, protecting unwritten data in the write buffer. Voltage and capacity match OEM part numbers 57DHN, 14GNX, 275FR, and J6131.

• PowerEdge 1750 and 2500 series compatibility: These servers share the same RAID controller battery socket, connector pinout, and BMS handshake protocol — one cell fits all listed models without modification.
• Bench tested on actual hardware: We ran this cell on a PERC controller under simulated cache-backup load. The BMS accepted the cell, completed voltage recognition, and held charge across the full test window. No false-low alerts triggered during the charge phase.
• Learn cycle initiation after swap: After installing this battery, trigger the learn cycle manually from your controller management interface — StorCLI: /cx bbu start learn. The controller holds in write-through mode until the learn cycle completes and recalibrates the backup window against the new cell. Do not rely on the auto-schedule for the first cycle.

RAID controller staying in write-through mode after battery swap

Write-through mode persists because the controller has not yet verified the new battery's backup window. The PERC firmware requires a full learn cycle — charge, discharge, recharge — before it trusts the cell enough to re-enable write-back caching. This cycle can take 24 to 72 hours under normal server load. Initiating it manually via StorCLI shortens the wait; otherwise the controller queues it on its own scheduled interval, which may be days away.

Management console showing battery error days after a confirmed good installation

This is a timing issue, not a cell fault. Dell's PERC controllers run their battery self-assessment on a fixed schedule — typically every 90 days — not at boot or at swap detection. If the scheduled test runs before the learn cycle finishes, the firmware logs an error because the backup window estimate is still uncalibrated. Force a manual learn cycle immediately after installation using StorCLI /cx bbu start learn, then allow the full cycle to complete before the next scheduled assessment. Once the cycle reports a valid backup window, the error clears on the next controller poll.