Akai CP161AUS Cordless Phone Replacement Battery 3.6V 600mAh

Akai CP161AUS / CP261AUS Series — 3.6V Ni-MH Replacement Battery

This is a 3.6V, 600mAh Ni-MH replacement battery for Akai cordless phone handsets. It fits the CP161AUS, CP250AUS, CP260AUS, and CP261AUS models. The cell pack matches the original voltage and physical dimensions, so it seats and charges in the handset without modification.

• CP161AUS / CP250AUS / CP260AUS / CP261AUS fit: These handsets share the same 3.6V single-cell NiMH pack format, connector orientation, and charge circuit. One pack covers all four models because the base station delivers the same trickle-charge current to each handset.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on the CP-series base station. The BMS accepted charge from cycle one, and cell voltage held within spec across five full cycles without thermal trip or charge rejection.
• First-charge protocol for NiMH handsets: Place the handset in the base immediately after installing this battery and leave it for a full 16 hours before first use. NiMH cells in cordless phones are shipped partially discharged — a slow initial charge lets the cells reach rated capacity and sets the baseline the handset uses to track charge state.

Base station showing no charge or error light on a new NiMH pack

Akai base stations use a voltage threshold to detect whether a handset is ready to accept charge. A fresh replacement NiMH pack can sit in storage long enough for its resting voltage to drop below that threshold — typically under 3.0V. When the base sees that low voltage, it interprets the pack as a fault rather than a flat battery and withholds current. Removing the handset, waiting 30 seconds, and reseating it triggers a fresh detection cycle. If the base still shows an error, leave the handset seated for 20–30 minutes — most Akai charger circuits will eventually push a recovery pulse once the pack voltage climbs above 3.2V.

Talk time shorter than expected after fitting a new battery

This is normal for the first three to five cycles on a fresh NiMH pack. New cells have not yet reached full crystalline alignment, so initial capacity runs short of the rated 600mAh. Each full charge-and-discharge cycle builds usable capacity incrementally. Run three complete cycles — full 16-hour charge followed by use until the low-battery alert sounds — and talk time will stabilise at rated capacity.