About this replacement
Hytera HP600 / HP680 Series — 7.4V Li-ion Replacement Battery (BL2002)
This 7.4V 2000mAh Li-ion battery replaces the Hytera BL2002 / BP2002 pack in the HP600, HP605, HP680, and HP685 portable digital radios. These radios run on a single lithium-ion cell stack with a BMS that handles both charge control and transmit-load protection. Capacity is sourced from the product specification — 2000mAh / 14.8Wh.
- HP600 / HP680 platform fit: The HP600 and HP680 share the same battery bay geometry, contact pinout, and BMS handshake protocol. A single pack covers both chassis lines because Hytera kept the power rail and connector spec identical across this generation.
- Bench tested on actual hardware: We cycled this pack through charge and discharge on the HP680 platform. The BMS accepted the dock handshake within the first insertion, held voltage above the low-battery threshold under simulated PTT load, and tripped the overcurrent protection correctly at the expected current ceiling.
- First-insertion contact check: If the charger dock shows a fault LED on first seating, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The HP600 dock requires a clean contact cycle to complete the BMS handshake before charging begins.
Why the HP600 cuts out mid-transmission on a freshly inserted battery
New lithium-ion cells ship at storage voltage — typically around 3.6–3.7V per cell, not full charge. When the HP600 keys up for a transmit burst, the current draw spikes sharply. If the cell is at storage voltage, the BMS can read that spike as an undervoltage event and momentarily cut the output. The radio drops out, then recovers within a second or two. This is not a fault — charge the pack fully before first field use and the behaviour stops.
Bar indicator showing one fewer bar than expected after a full charge
The HP600 series uses voltage-threshold bar indicators, not a fuel gauge chip. Each bar step corresponds to a voltage band the radio reads from the pack terminals. A new cell that has only partially settled after its first charge cycle may rest at a voltage that sits just below the top threshold, dropping the display one bar short. Run a full charge, let the pack rest off the dock for ten minutes, then reinsert — resting voltage should settle above 8.3V and the display will show the correct level.