About this replacement
Hytera TC-880GM / TC-890GM — 7.4V Li-ion Replacement Battery (BL2404)
This is a 7.4V 2800mAh Li-ion replacement for the Hytera BL2404 battery pack. It fits the TC-880GM and TC-890GM portable two-way radios. Capacity is rated at 2800mAh (20.72Wh) — use the original charger dock and existing belt clip hardware.
- TC-880GM and TC-890GM platform fit: Both models run the same 7.4V power rail, share the BL2404 connector footprint, and use the same BMS handshake protocol with Hytera charger docks — so one pack covers both radios without modification.
- Bench tested on actual hardware: We cycled this pack through transmit and receive loads on the TC-880GM platform. The BMS held voltage across simulated PTT bursts and returned correct charge-acceptance signals to the dock on every test cycle.
- First-insertion contact check: If the charger dock shows a fault LED on first insertion, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The Hytera dock requires a clean contact cycle to recognise the new BMS before charging begins.
Why the TC-880GM cuts out mid-transmission on a new BL2404
A new Li-ion cell ships at storage voltage — typically 3.6–3.7V per cell, not full charge. When you key the PTT on a storage-voltage pack, the transmit current spike can pull cell voltage below the BMS overcurrent threshold instantly. The BMS trips and the radio cuts out, which looks like a faulty battery but is actually the protection circuit doing its job. Charge the pack fully to 8.4V before the first use and the cutout stops.
Bar indicator showing one fewer bar than expected after a full charge
The TC-880GM uses voltage-threshold bar indicators — each bar corresponds to a voltage band, not a percentage from a fuel gauge chip. A new pack sometimes reads one bar short because the cells haven't settled after the first charge cycle; resting voltage can sit slightly below the top threshold for up to an hour after the charger goes green. Let the pack rest off charge for 30–60 minutes, then reinsert — the bar display should step up to match the actual resting voltage near 8.2–8.4V.