Teletalk 7105A Cordless Phone Compatible Battery 3.6V 600mAh

Teletalk 7105A — 3.6V Ni-MH Replacement Battery

This is a 3.6V, 600mAh Ni-MH battery for the Teletalk 7105A cordless phone handset. It replaces the original pack when the handset no longer holds charge or stops powering on. Dimensions are 45.30 x 31.10 x 10.75mm — check these against your existing cell before ordering.

• Teletalk 7105A handset compatibility: This pack matches the voltage rail and connector format the 7105A handset expects. Ni-MH chemistry is correct for this handset — do not substitute Li-ion packs, as the base station charger circuit is calibrated for Ni-MH charge curves only.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on a cordless phone test rig. The BMS accepted charge from a standard Ni-MH base station without error flags, and the cell reached rated capacity after three full conditioning cycles.
• First installation charge — 7105A specific: After fitting this pack, seat the handset in the base and leave it for a full 16 hours before use. Ni-MH cells shipped in storage state sit below the base station's acceptance threshold — the slow first charge is what brings the cell up to rated capacity.

Base station showing no charge light after fitting a new Ni-MH pack

Ni-MH cells lose voltage during storage. If the pack sits in a warehouse long enough, its resting voltage can drop below the minimum the 7105A base station needs to recognise a valid battery and begin charging. The base interprets this as an absent or faulty pack, so the charge indicator never lights. The fix is to briefly jump-start the cell — place the handset in the base, remove it after 30 seconds, then reseat it firmly. Repeat two or three times. Most base stations will pick up the cell once its voltage nudges above 3.0V.

Talk time shorter than expected for the first week after replacement

New Ni-MH cells do not deliver full rated capacity on the first charge cycle. The crystal structure inside the cell needs three to five full charge-discharge cycles before it reaches 600mAh. If the handset is running short before that point, that is normal behaviour — not a fault with the pack. Run the handset until the low-battery warning sounds, then return it to the base for a full charge. After five cycles, capacity stabilises at the rated figure.