Kenwood Primo IS-C10 Replacement Battery 3.6V 1200mAh

Kenwood Primo IS-C10 / Martin Dawes MD110 — 3.6V Ni-MH Replacement Battery

This 3.6V, 1200mAh Ni-MH battery replaces the original pack in the Kenwood Primo IS-C10 and Martin Dawes MD110 cordless handsets. Both phones use the same voltage rail, cell format, and connector, so one battery serves both models. Dimensions are 52.00 × 42.30 × 14.20mm — confirm these match your existing pack before ordering.

• Primo IS-C10 and MD110 compatibility: These two handsets share the same battery bay geometry, 3.6V NiMH voltage requirement, and contact arrangement. The shared base station charging circuit accepts the same charge profile, so no modifications are needed.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on a NiMH-compatible test rig. The cells accepted a full charge and held voltage within the expected range across five consecutive cycles without thermal anomaly.
• First-charge protocol for NiMH cordless packs: Place the handset in the base station immediately after fitting this battery and leave it undisturbed for a full 16 hours before first use. NiMH cells in cordless phones need this slow initial charge to reach rated capacity — skipping it reduces what you get from the first few cycles.

Base station showing no charge or flashing error light after fitting a new NiMH pack

NiMH batteries discharged during storage can arrive with a resting voltage below the threshold the Primo IS-C10 base station expects before it begins charging. The base reads this as a fault rather than a flat battery, so the charge indicator never activates. Remove the handset, leave it out of the base for 60 seconds, then reseat it firmly — this resets the handshake. If the error persists, the cells may need a brief pre-charge pulse; a standalone NiMH charger set to 100mA can bring the pack up to 3.0V, after which the base station will accept it normally.

Talk time shorter than the original battery after replacement

New NiMH cells do not deliver rated capacity on the first cycle — this is normal cell chemistry, not a defect. Capacity builds over three to five full charge-discharge cycles as the crystalline structure inside each cell stabilises. Run the handset until it cuts out, return it to the base for a full charge, and repeat. By cycle five, voltage under RF transmit load should stay above 3.2V and talk time will reflect the rated 1200mAh capacity.