Motorola MD4150 Replacement Battery 3.6V 700mAh

Motorola MD4150 / MD4160 — 3.6V Ni-MH Replacement Battery

This 3.6V, 700mAh Ni-MH battery replaces the original handset battery in the Motorola MD4150 and MD4160 cordless phones. It slots directly into the handset battery compartment and restores power to the handset's DECT radio and display. Dimensions are 48.46 × 31.16 × 10.67mm — confirm these against your existing pack before ordering.

• MD4150 and MD4160 compatibility: Both models run the same 3.6V single-cell NiMH battery bay with an identical connector orientation and cell footprint. One replacement covers both handsets.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on a NiMH-compatible analyser. The cell held voltage above the DECT transmit threshold through multiple discharge cycles, and the base station accepted the pack without a charge-error light.
• First-charge protocol for NiMH cordless handsets: After installing, seat the handset in the base cradle for a full 16 hours before first use. NiMH cells ship partially discharged and need a slow full charge to reach rated capacity — skipping this step means the first few sessions will feel short.

Talk time shorter than the original battery after replacement

NiMH cells don't reach full rated capacity on the first charge cycle. The MD4150's charging circuit applies a trickle charge, and a fresh cell needs three to five full charge-and-discharge cycles before it delivers its rated 700mAh. If talk time feels short in the first week, this is normal cell conditioning — not a fault. Run the handset until the low-battery indicator fires, return it to the base, and repeat for four or five cycles.

Base station charge light stays off or shows error after battery swap

NiMH packs that have been in storage can drop below the voltage threshold the MD4150 base uses to detect an inserted battery. If the base shows no charge activity after seating the handset, remove the battery and measure its open-circuit voltage — a reading below 3.0V means the base won't initiate a charge. In that case, use a standalone NiMH charger to bring the pack to around 3.3V first, then return it to the base cradle to complete the full charge cycle.