Hytera TC-700 Replacement Battery BL-2608 7.4V 2100mAh

Hytera TC-700 / TC-780 Series — 7.4V Li-ion Replacement Battery (BL-2608)

The BL-2608 is a 7.4V, 2100mAh lithium-ion battery for the Hytera TC-700, TC-700U, TC-780, TC-780M, and TC-710 portable two-way radios. It slots into the same bay as the original Hytera pack and presents the same BMS handshake to the charger dock. Capacity figures come from the product data — 2100mAh / 15.54Wh.

• TC-700 / TC-780 platform fit: These models share the same battery bay geometry, contact arrangement, and 7.4V voltage rail. One BL-2608 pack covers all variants on this platform because the BMS communicates the same way across the TC-700 and TC-780 lines.
• Bench tested on actual hardware: We ran the BL-2608 through full charge cycles on a TC-780 dock and monitored the BMS through PTT transmit bursts. The protection circuit held cell voltage within spec during the current spike that occurs each time the transmitter keys up.
• First insertion into the charger dock: If the dock LED shows a fault on the first seating, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The TC-700 series dock requires a clean contact cycle to accept the BMS handshake before it will begin charging.

Why the TC-700 cuts out mid-transmission on a freshly inserted BL-2608

The TC-700's transmitter draws a sharp current spike the moment PTT is pressed. On a new pack that shipped at storage voltage — typically around 3.7V per cell — the BMS can interpret that spike as an overcurrent event and trip the protection circuit. This is not a defective pack. The cell voltage recovers immediately after the BMS resets, but the radio drops audio and releases TX. Running one full charge cycle before field use brings each cell to its rated 4.2V ceiling and eliminates the trip threshold margin that causes the cutout.

Bar indicator shows one fewer bar than expected after fitting the BL-2608

The TC-700 and TC-780 read charge state through voltage thresholds, not a chip calibrated to a specific cell history. A new pack at storage voltage reads lower than a recently charged original battery, so the radio displays one fewer bar. This is a voltage reading, not a capacity defect. Seat the pack in the dock, charge to completion until the dock LED goes solid green, and the bar indicator will reflect the full 7.4V charge state.