About this replacement
Hytera PD680 CQST Series — 7.2V Li-ion Replacement Battery (BL2020)
The BL2020 is a 7.2V 2500mAh Li-ion battery for Hytera professional portable radios. It fits the PD680 CQST, PD600 UL913, PD660 UL913, PD680 UL913, and more than a dozen additional PD-series models. Voltage and capacity match the OEM BL2020 specification exactly.
- PD600 / PD660 / PD680 platform fit: These models share the same 7.2V battery rail, contact layout, and BMS handshake protocol. One pack covers the full PD-series lineup using the BL2020 form factor — no adapter or modification needed.
- Bench tested on actual hardware: We cycled this pack in a PD680 chassis and monitored BMS response under transmit load. The protection circuit held within spec at peak PTT current draw, and the dock accepted the handshake on the first insertion cycle.
- First insertion on a Hytera dock: If the charger shows a fault LED on first seating, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The Hytera dock runs a contact-verification cycle before it accepts a new BMS — a single dirty contact fails that check every time.
Why the PD680 cuts out mid-transmission on a freshly inserted BL2020
A new Li-ion cell ships at storage voltage — typically 3.6–3.7V per cell, not full charge. When the PD680 drives the PA stage at full transmit power, current demand spikes sharply. If the pack is at storage voltage, the BMS sees that spike as a potential overcurrent event and briefly throttles output. The radio interprets the voltage dip as a low-battery condition and cuts TX. Charge the pack to full before the first shift — the cutout stops once cells are above 4.1V per cell.
Bar indicator shows one bar fewer than expected after fitting a new BL2020
Hytera's PD-series bar indicator reads voltage thresholds directly — it has no memory of charge history. A pack delivered at storage voltage sits in the lower threshold band, so the radio displays fewer bars even though the cell capacity is intact. This is not a faulty pack. Run a full charge cycle first; once resting voltage reaches approximately 8.3–8.4V for the pack, the indicator will climb to full bars.