About this replacement
Icom IC-M34 / IC-M36 Series — 7.2V Li-ion Replacement Battery (BP-252)
This 7.2V 950mAh Li-ion pack replaces the BP-252, BP-241, and BP-224H batteries across Icom's compact handheld marine VHF lineup. It fits the IC-M34, IC-M36, IC-GM1600, and IC-GM1600E, among others. Voltage and capacity match OEM spec exactly — no adapter or modification needed.
- IC-M34 / IC-GM1600 platform fit: These models share the same battery bay dimensions, contact layout, and 7.2V BMS handshake. The pack slides into any of them without modification. The BMS communicates charge state to the dock via the same three-contact strip across all listed models.
- Bench tested on actual hardware: We ran this pack through the IC-M34 charger dock and confirmed BMS acceptance, full charge cycle completion, and stable voltage output under simulated PTT transmit load. The BMS held within spec during the current spike at PTT press.
- First insertion into the dock: If the dock shows a fault LED on first insertion, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The Icom dock requires a clean contact cycle to complete the BMS handshake before it begins charging.
IC-M34 charger dock fault LED after BP-252 swap
A new Li-ion pack ships at storage voltage — typically 3.6–3.7V per cell, which puts the pack around 7.2–7.4V total. Some Icom dock firmware interprets a fresh pack at storage voltage as a fault condition rather than a charge request. This triggers the red fault LED even though the pack is not defective. Remove the pack, clean the contacts, and reseat — most docks accept the pack on the second or third attempt once the BMS handshake completes cleanly.
Bar indicator showing one fewer bar than expected on a new pack
The IC-M34 uses voltage-threshold bar indicators — each bar corresponds to a voltage band, not a percentage reading. A new pack at storage voltage will display fewer bars than a fully charged one, even if the pack is not faulty. Run the pack through a full charge cycle in the dock before reading the bar indicator. After a complete charge, the pack should hold at or above 8.2V open-circuit and display full bars.