Kadus HR-AAAU Clipper HS70 Compatible Battery 3.6V 700mAh

Kadus Clipper HS70 — 3.6V Ni-MH Replacement Battery (HR-AAAU)

This is a 3.6V, 700mAh Ni-MH replacement battery for the Kadus Clipper HS70 professional hair clipper. It slots into the clipper's battery bay and restores power to the motor when the original cell no longer holds a charge. OEM part number HR-AAAU, also cross-referenced as 1520902.

• HS70 motor compatibility: The HS70 runs a low-voltage DC motor rated for 3.6V — the same voltage rail this Ni-MH cell delivers. The BMS handshake on this clipper expects Ni-MH chemistry; fitting a Li-ion cell at a different nominal voltage will cause the charging circuit to misread state-of-charge and cut off early.
• Bench tested on actual hardware: We cycled this battery through full charge and discharge on the HS70 platform. The BMS accepted the cell without fault flags, and motor draw stayed consistent across the discharge curve without triggering premature cutoff.
• Post-trim cleaning tip: If you rinse the HS70 clipper head after use, let the housing air-dry for at least 30 minutes before returning it to the charging stand. Moisture sitting between the charging contacts bridges them and triggers a BMS protection trip the device reports as a battery fault rather than a contact fault.

Why the HS70 motor slows down before the low-battery indicator activates

Ni-MH cells drop voltage under load before the resting voltage falls enough to trip the indicator threshold. The HS70's motor draws a short current spike on startup, which drags cell voltage below the motor's stable operating range briefly — you feel this as a sluggish cut. As the battery ages, internal resistance rises and this sag deepens, so the motor slows noticeably while the indicator still shows adequate charge. Replacing the cell restores a low internal resistance and keeps voltage above the sag threshold during motor load.

Indicator shows full charge but clipper loses power within seconds of switching on

This happens when the Ni-MH cell has developed a memory effect from repeated partial cycling — the cell's usable voltage window has shrunk but the charger still reads the resting voltage as full. Under the motor's actual load, voltage collapses immediately and the BMS trips the output. The fix is not a longer charge — the cell itself needs replacement. After fitting the new cell, run a full charge to 4.2V cutoff before first use to let the BMS calibrate the state-of-charge window correctly.