About this replacement
Icom IC-A6 / IC-A24 Series — 7.2V Ni-MH Replacement Battery (BP-209N / BP-210N)
This is a 7.2V, 2500mAh Ni-MH replacement battery for the Icom IC-A6, IC-A6E, IC-A24, IC-A24E, and over 30 additional Icom handheld aviation transceivers. It replaces OEM part numbers BP-209, BP-209N, BP-210, BP-210N, BP-222, and BP-222N. The pack slots into the original battery bay and connects via the same multi-pin contact strip as the factory unit.
- IC-A6 / IC-A24 platform fit: These models share a common 7.2V two-cell Ni-MH architecture with the same contact pin layout and BMS handshake protocol. That is why one pack covers the full BP-209 and BP-210 replacement family without adapter or modification.
- Bench tested on actual hardware: We ran this pack in an IC-A24E dock and under a PTT transmit load. The BMS held voltage above the 6.0V cutoff threshold through repeated transmission cycles, and the charger dock advanced to charge status without manual reset.
- First-cycle contact seating on Icom docks: 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. Icom charging docks require a clean contact cycle to recognise a new pack's BMS handshake before charging begins.
Why the IC-A6 cuts out mid-transmission on a fresh Ni-MH pack
Ni-MH cells leave storage at roughly 60–70% of rated voltage. When PTT is pressed, transmit current spikes sharply and the BMS sees a voltage drop it reads as an overcurrent event, tripping the protection circuit before the pack has been properly conditioned. Running two or three full charge-discharge cycles through the Icom BC-144 or BC-191 dock brings cell voltage up to the 8.4–8.5V fully charged threshold and stabilises internal impedance. After conditioning, the pack sustains the transmit current spike without triggering a BMS cutoff.
Bar indicator showing one fewer bar than expected after a full charge
Icom aviation handhelds use a simple voltage-threshold bar display, not a fuel gauge chip. A new Ni-MH pack that has not been through a conditioning cycle sits below the top voltage threshold the radio expects at 100%, so it displays one bar short even when the dock shows green. This is a voltage-reading artefact, not a capacity fault. Charge the pack fully, allow it to rest for 15 minutes off the dock, then power on the radio — cell voltage will have settled and the bar indicator will read correctly.