Code A Phone 3100 Ni-MH Cordless Phone Compatible Battery 3.6V 170mAh

Code A Phone 3100 / 3200 — 3.6V Ni-MH Replacement Battery

This is a 3.6V, 170mAh Ni-MH replacement battery for the Code A Phone 3100 and 3200 cordless phone handsets. It slots into the handset battery compartment and restores talk and standby function when the original pack has degraded. No OEM part number applies to this unit — fitment is confirmed by model number and physical dimensions (50.60 x 25.83 x 14.07mm).

• 3100 and 3200 fitment: Both models run the same 3.6V battery rail with identical connector orientation and compartment dimensions. The handset BMS on this series accepts standard Ni-MH chemistry without a proprietary handshake, so the swap is straightforward.
• Bench tested on actual hardware: We cycled this pack through the 3100 base station and confirmed the charging circuit accepted the new cell without error. The BMS tracked charge state normally across three full cycles and voltage held steady under RF transmit load.
• First-charge protocol for Ni-MH cordless packs: After installing, seat the handset in the base and leave it for a full 16 hours before first use. Ni-MH cells from storage ship at partial charge and need one slow, uninterrupted cycle to reach rated capacity — skipping this shortens usable talk time from the start.

Base station showing no charge light on a fresh Ni-MH pack

Ni-MH batteries lose voltage during storage and can drop below the threshold the base station uses to detect a valid pack. When the resting voltage is too low, the base treats the battery as absent or faulty and withholds charging current entirely. This is common with new replacement packs that have been sitting in a warehouse. To recover, hold the handset in the base for 15–30 minutes — most Code A Phone base stations will begin a trickle charge once the terminal voltage climbs above approximately 3.0V.

Talk time shorter than the original battery after three charges

Ni-MH cells do not reach full rated capacity on the first charge cycle. The 3100 and 3200 handsets use a slow trickle-charge circuit, which means the first two or three cycles will feel short compared to a fully conditioned pack. Capacity builds progressively over the first three to five full charge-and-discharge cycles. If talk time is still noticeably short after five cycles, check that the handset is seating flush in the base — a loose contact drops charging current and the pack never reaches a full 3.6V charge.