Kathrein KT951 Cordless Phone Replacement Battery 3.6V 1200mAh

Kathrein KT951 — 3.6V Ni-MH Replacement Battery

This is a 3.6V 1200mAh Ni-MH replacement battery for the Kathrein KT951 cordless DECT handset. It slots into the handset where the original battery sits and restores wireless operation when the factory cell no longer holds a charge. Capacity is 1200mAh (4.32Wh), matching the original specification.

• KT951 handset fit: The KT951 handset runs on a single 3.6V NiMH cell pack at this physical footprint — 56.32 x 42.96 x 20.38mm. That combination of voltage, chemistry, and dimensions is what the handset's charging circuit expects. Swapping to a different chemistry or voltage causes charging errors at the base station.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a cordless phone test rig. The BMS accepted the NiMH charge profile without fault, and the cell reached rated voltage within the expected window on a standard DECT base charge cycle.
• First charge after installation: Place the handset in the base immediately after fitting this battery and leave it for a full 16 hours before first use. NiMH cells shipped in storage state need a slow, uninterrupted first charge to reach rated capacity — cutting this short leaves usable capacity on the table for the first several cycles.

Talk time shorter than the original battery after replacement

NiMH cells do not deliver full rated capacity straight out of the box. The electrochemical structure needs three to five full charge-discharge cycles before the cell stabilises at its rated 1200mAh. Each cycle, talk time steps up noticeably. If talk time still seems short after five full cycles, check that the handset sits fully and squarely in the base — a partial contact gives the cell a shallow charge rather than a complete one.

Base station showing no-charge or error light after fitting new battery

A NiMH cell stored for any length of time self-discharges, sometimes to a voltage the base station's charging circuit reads as a fault rather than a flat battery. The base expects to see a cell above a minimum threshold voltage before it starts the charge cycle. Remove the handset, leave it out for 30 seconds, then reseat it firmly — this resets the base's detection cycle. If the error light persists, check the battery contacts on both the handset and the base for oxidation and clean with a dry cloth before reseating.