Makita 4076 Replacement Battery 7.2V 3000mAh Ni-MH

Makita 4076DWR / 4076DWX Series — 7.2V Ni-MH Replacement Battery (810534-3)

This is a 7.2V, 3000mAh Ni-MH replacement battery for the Makita 4076 series cordless vacuum cleaner. It fits the 4076, 4076D, 4076DWR, and 4076DWX models. Swap it in when the original battery no longer holds charge and suction starts dropping well before the indicator shows low.

• 4076 series compatibility: These models all run the same 7.2V cell pack with matching connector geometry and BMS signalling. The 4076DWR and 4076DWX share the same battery bay as the base 4076D — no adapter needed.
• Bench tested on actual hardware: We cycled this cell through full discharge under sustained motor load. The BMS held voltage within spec across the draw curve, and the protection circuit tripped correctly on overcurrent before thermal damage could occur.
• Dock charging on the Makita 4076: Do not leave the vacuum sitting on the charging dock once full. Continuous dock charging on Ni-MH cells causes trickle-charge damage that accelerates capacity fade. Charge to full, then remove from the dock until the next use.

Suction dropping before the battery indicator reaches low

On Ni-MH cells, voltage sag under motor load can exceed what the indicator circuit measures at rest. The vacuum's motor sees less voltage than the indicator expects, so suction weakens while the light still shows green. A partially blocked filter makes this worse — restricted airflow forces the motor to draw harder, pulling voltage down faster. Clean the filter first, then check whether the symptom persists on a fresh charge cycle.

Motor cuts out mid-clean then recovers after a pause

This is a BMS overcurrent trip, not a dead battery. It happens when sustained restricted suction — usually a clogged filter or blockage near the nozzle — causes the motor to draw above the BMS threshold. The protection circuit cuts power, and the vacuum recovers once the cell cools slightly. Clear any blockage, clean the filter, and confirm resting cell voltage sits above 7.0V before ruling out a weak cell.