Retevis RB15 DT22 Compatible Battery 3.7V 1100mAh

Retevis RB15 — 3.7V Li-ion Replacement Battery (DT22)

This is a 3.7V, 1100mAh Li-ion replacement for the Retevis RB15 two-way radio. It uses the OEM part number DT22 and slots directly into the RB15 battery compartment. Voltage and cell chemistry match the original pack specification.

• RB15 platform fit: The RB15 runs a single-cell 3.7V Li-ion architecture. The DT22 format matches the connector orientation and housing thickness — 5.70mm — so the battery seats flush and the radio cover closes without gap or flex.
• Bench tested on actual hardware: We cycled this pack through transmit loads on the RB15 and confirmed the BMS holds rail voltage through sustained PTT events without tripping overcurrent cutoff. Cell voltage at rest after full charge measured within the expected 4.1–4.2V window.
• First-insertion contact check: If the charger dock shows a fault LED on first insertion, remove the battery, wipe the gold contact strip with a dry cloth, and reseat firmly. The RB15 dock requires a clean contact cycle to complete the BMS handshake before charging will start.

Why the RB15 cuts out mid-transmission on a new DT22

New Li-ion cells ship at storage voltage — typically 3.6–3.7V — not full charge. When the RB15 PTT is pressed, transmit current spikes sharply. If the cell hasn't been fully charged first, the BMS can read that spike as an undervoltage event and cut the output rail. The radio goes silent mid-transmission. A full charge cycle before first use brings the cell to 4.1–4.2V, giving the BMS enough headroom to handle the transmit surge without triggering cutoff.

RB15 bar indicator showing one fewer bar than expected after swap

The RB15 uses a voltage-threshold bar indicator — it reads resting cell voltage and maps it to bars. A new pack at storage voltage reads lower than a fully charged cell, so the indicator shows one or two bars even though the battery isn't depleted. This is not a fault with the pack. Charge the DT22 fully in the dock until the LED goes green, then reinsert — the indicator should climb to full bars at or above 4.1V resting.