Coby CTP8200 Replacement Battery 3.6V 700mAh Ni-MH

Coby CTP8200 / CTP8800 Series — 3.6V Ni-MH Replacement Battery

This is a 3.6V, 700mAh Ni-MH replacement battery for the Coby CTP8200, CTP8250, CTP8800, and PM38BAT handsets. It fits directly into the battery compartment and connects to the same contacts as the original pack. Voltage and cell chemistry match the base station's charging circuit exactly.

• CTP8200, CTP8250, CTP8800, and PM38BAT compatibility: All four models share the same 3.6V single-cell NiMH rail, connector pitch, and physical footprint — one pack covers the full range without modification.
• Bench tested on actual hardware: We cycled this pack through the base station charging circuit and confirmed the BMS accepted charge from the first dock. Charge current stayed within the trickle-charge window the base station expects from a NiMH cell.
• First-charge protocol for NiMH cordless handsets: After installing, seat the handset in the base and leave it for a full 16 hours before first use. NiMH cells in cordless phones are shipped partially discharged — skipping this slow first charge prevents the pack from reaching its rated 700mAh capacity.

Talk time shorter than rated after replacing the battery

NiMH cells don't deliver full capacity on cycle one. The electrodes need three to five full charge-discharge cycles before the chemistry stabilises at its rated output. If talk time feels short in the first few days, that's normal cell conditioning — not a faulty pack. Run the handset down fully and return it to the base each time, and capacity will increase noticeably by cycle three.

Base station shows no charge or error light with new pack installed

NiMH packs stored before sale can drop below 3.0V, which some Coby base stations won't recognise as a valid battery. The base expects to see a cell voltage above its detection threshold before it opens the charge circuit. If the charge indicator stays off, remove the handset, wait 10 seconds, and re-seat it firmly — this triggers the base to re-sample the battery voltage. If that fails, check that the handset contacts are clean and making full contact with the base pins.