About this replacement
Baofeng BL-5 / BL-5L — 7.4V Li-Polymer Replacement Battery
This 7.4V 2600mAh (19.24Wh) lithium-polymer pack replaces the Baofeng BL-5 and BL-5L batteries in Baofeng handheld transceivers. The cell format, connector orientation, and BMS pinout match the original so the radio's voltage-threshold bar indicator reads correctly from first power-on. Capacity figure is from the product data — 2600mAh at 7.4V nominal.
- BL-5 and BL-5L platform fit: Both OEM part numbers share the same physical housing, contact strip layout, and 7.4V voltage rail. The BMS communicates the same handshake signal the radio expects, so the bar indicator steps through thresholds without recalibration.
- Bench tested on actual hardware: We cycled this pack through repeated PTT transmit bursts to confirm the BMS handles the current spike without triggering overcurrent lockout. Voltage held stable under sustained RF output and recovered cleanly between transmissions.
- 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. New packs arrive at storage voltage — the dock may need a clean contact cycle to accept the BMS handshake before charging begins.
Why the BL-5 bar indicator shows one fewer bar than expected on a fresh pack
Baofeng handhelds use simple voltage-threshold steps to drive the bar indicator — no fuel gauge chip. New cells leave the factory at around 3.7–3.8V per cell, which sits at the low end of the display range. The radio reads that storage voltage and maps it to a lower bar count. One full charge cycle brings both cells to 4.2V each, and the indicator steps up to reflect the actual state of charge.
Radio cuts out completely when PTT is pressed on the new pack
A hard cut-out on PTT press points to the BMS triggering overcurrent protection, not a faulty cell. Transmit current in a handheld transceiver spikes sharply the moment the RF stage fires — if the pack sat in storage long enough, the BMS threshold can trip at that initial surge. Remove the pack, reinsert it, and attempt a short low-power transmission first. If the cut-out clears, run two or three partial charge cycles to let the BMS settle; resting voltage should read at least 7.2V before a full transmit test.