EXTEL PASFCB Cordless Phone Replacement Battery 3.6V 300mAh

EXTEL PASFCB — 3.6V Ni-MH Replacement Battery

This is a 3.6V, 300mAh Ni-MH replacement battery for the EXTEL PASFCB cordless handset. It slots into the handset battery compartment and restores wireless operation when the original cell can no longer hold a charge. Capacity is 300mAh (1.08Wh), matching the original specification.

• PASFCB handset fit: The PASFCB uses a compact 3-cell Ni-MH pack on a 3.6V rail. The physical dimensions — 31.00 × 30.41 × 10.64mm — match the original cavity, and the connector orientation aligns with the handset's battery port. No modification needed.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on a DECT handset platform at 3.6V. The BMS accepted charge from the base station without triggering a fault light, and the cell voltage held stable across standby and active call draw.
• First charge on NiMH cordless packs: After installing, seat the handset in the base and leave it for a full 16 hours before first use. NiMH chemistry in cordless phones needs a slow initial charge to reach rated capacity — skipping this step will reduce usable talk time on early cycles.

Talk time shorter than expected on a new pack

NiMH cells ship partially discharged and need three to five full charge-discharge cycles before they deliver rated capacity. On cycle one, you may see noticeably shorter talk time — this is normal, not a fault. Each full cycle conditions the cell chemistry and pushes usable capacity closer to the rated 300mAh. After five cycles, talk time should stabilise at or near the original battery's performance.

Base station charge indicator not activating on a fresh battery

DECT base stations check incoming voltage before initiating a charge cycle. A Ni-MH pack that has sat in storage can drop below the threshold the base expects — typically under 3.0V — causing the base to show no charge light or an error indicator. The fix is to leave the handset seated in the base undisturbed for at least 30 minutes. The trickle circuit will raise cell voltage enough for the base to recognise the pack and switch to full charge mode.