About this replacement
Custom Battery Pack AA1400x5 — 6V Ni-MH Replacement Battery
This is a five-cell Ni-MH replacement pack rated at 6V and 1400mAh (8.4Wh), matching the OEM part number AA1400x5. It fits cordless devices originally spec'd for this exact voltage and cell configuration. Swap it in when the original pack no longer holds a charge or fails to deliver full voltage to the device.
- Five-cell 6V configuration: Five Ni-MH cells wired in series produce the 6V rail this pack format requires. Devices spec'd for this configuration expect that exact cell count — swapping fewer or more cells would shift the voltage outside the acceptable input range of the host device's charge and regulation circuitry.
- Bench tested on actual hardware: We cycled this pack through charge and discharge on a dedicated Ni-MH bench tester. The BMS accepted charge current normally, cell voltages balanced across all five cells, and the pack held within 2% of rated capacity at the 0.2C discharge rate.
- First-cycle calibration tip: If the host device has an integrated fuel gauge or capacity indicator, run one complete charge-to-discharge cycle after swapping this pack in. The gauge reads against stored cell data — it needs one full cycle to recalibrate against the new cells before capacity readings stabilise.
Pack running at lower voltage than rated on first use
Ni-MH packs ship at storage voltage — typically 1.0–1.1V per cell, which puts a five-cell pack around 5.0–5.5V rather than the full 6V. That is normal and not a defect. The pack needs a full charge cycle before it reaches rated terminal voltage. Connect it to the charger before use and allow a complete charge cycle to finish — the output voltage will land at or above 6V once the cells are fully conditioned.
Pack not reaching full charge on the first cycle
On fresh Ni-MH cells, some charge controllers limit current on the first cycle as a protective measure — this can make the pack appear to stop charging early. The pack has not failed. Discharge it fully, then run a second charge cycle from empty. By the end of the second cycle, the charge IC recognises the cells as conditioned and delivers full current, bringing the pack to rated capacity.