NetApp N3600 RAID Controller Replacement Battery 7.4V 6800mAh

Nexergy NetApp N3600 — 7.4V Li-ion Replacement Battery (271-00011)

This 7.4V 6800mAh (50.32Wh) lithium-ion battery replaces OEM part 271-00011 in the NetApp N3600 RAID storage controller. It provides backup power to the controller's write cache during an unexpected power loss, protecting data held in volatile memory. When the existing cell degrades, the controller drops to write-through mode and cached data becomes vulnerable.

• NetApp N3600 controller fit: The N3600 controller uses a dedicated battery-backed write cache circuit. This cell matches the 7.4V nominal voltage rail and the connector pinout the controller expects for BMS handshake and charge-state reporting over the SMBus interface.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the controller interface. The BMS reported charge state correctly, the controller accepted the cell without fault codes, and write-back mode was restored after the learn cycle completed.
• Post-installation learn cycle: After fitting this battery, initiate a learn cycle from the ONTAP management interface using system controller battery show. The controller will stay in write-through mode until the cycle completes and recalibrates the backup window estimate against the new cell's actual capacity. This takes 24–72 hours under normal load.

RAID controller staying in write-through mode after battery swap

Swapping the battery does not automatically return the controller to write-back mode. The N3600 controller requires the battery to pass a full learn cycle before it trusts the new cell's reported backup window. Until that recalibration completes, the controller treats the battery state as unknown and keeps write caching disabled. Run system controller battery show in ONTAP to monitor learn cycle status — write-back mode re-enables once the controller confirms a backup window above its minimum threshold, typically above 3.0V per cell at end-of-discharge.

ONTAP showing a battery error several days after installation

ONTAP runs its battery assessment on a timed schedule, not at the moment you install a new cell. If the scheduled self-test fires before the learn cycle has finished, the controller may log a battery fault even though the cell is functioning correctly. The fault clears on the next assessment once the learn cycle has completed and the BMS can report a valid backup window. If the error persists beyond 72 hours post-installation, check cell voltage at the connector — it should read between 7.2V and 8.4V under float charge.