Midland T71 BATT10 Replacement Battery 3.6V 1500mAh

Midland T71 / T75 / T77 / T79 Series — 3.6V Ni-MH Replacement Battery (BATT10)

This is a 3.6V, 1500mAh Ni-MH replacement battery for the Midland T71, T75, T77, and T79 two-way radios. It matches the OEM BATT10, AVP13, and PB-X7 part numbers. The pack fits the original battery compartment and connects via the same contact strip as the factory unit.

• T71–T79 platform fit: These four models share the same battery bay dimensions, contact layout, and 3.6V voltage rail. One pack covers the full series because the dock and radio draw identical current profiles across all variants.
• Bench tested on actual hardware: We ran this pack through full charge cycles and PTT transmit bursts on a T71 unit. The BMS handled the transmit current spike without tripping, and the charger dock accepted the handshake without a fault LED on first insertion.
• First-insertion contact check on the Midland dock: If the dock shows a fault LED immediately after inserting a new pack, remove it, wipe the gold contact strip with a dry cloth, and reseat firmly. The Midland dock runs a contact-continuity check before it begins charging — a residue film from packaging is enough to fail it.

Why the T71 cuts out mid-transmission on a new battery

A Ni-MH cell ships at storage voltage — typically 1.1–1.15V per cell, or around 3.3–3.45V for a three-cell pack. When PTT is pressed, the radio draws a short high-current spike to power the RF stage. If the cell voltage is at storage level rather than full charge, that spike pulls the pack below the radio's low-voltage cutoff threshold. The radio interprets this as a depleted battery and cuts the transmission. Charge the pack fully before first use — the dock needs to bring the pack above approximately 3.8V before the radio will sustain TX without dropout.

Bar indicator showing one fewer bar than expected after a full charge cycle

The T71 uses a simple voltage-threshold bar display — each bar corresponds to a voltage band, not a percentage calculated by any fuel gauge chip. A new Ni-MH pack often reads one bar low for the first two or three charge cycles because the cells haven't yet reached peak capacity. This is a cell-formation effect, not a fault. Run two to three full charge and discharge cycles and the resting voltage will stabilise at the level the radio expects for a full-bar reading.