Kirisun DP405 Compatible Battery KB-760 7.4V 2000mAh

Kirisun DP405 / S760 Series — 7.4V Li-ion Replacement Battery (KB-760)

This 7.4V, 2000mAh Li-ion pack replaces the KB-760 and KB-760B batteries in Kirisun portable two-way radios. It fits the DP405, DPP418D, S565, S760, and five additional Kirisun models sharing the same battery bay and connector. Voltage and capacity match OEM spec — no modification needed.

• DP405 / S760 platform fit: These models share a common 7.4V rail, identical connector pinout, and the same BMS handshake protocol. One pack covers the full platform because the dock recognises the same cell configuration on first insertion.
• Bench tested on actual hardware: We ran this pack through a full charge and transmit-load cycle. The BMS held the voltage rail steady under simulated PTT burst draws, and the protection circuit tripped correctly at the low-voltage threshold without latching into lockout.
• First-insertion contact check: If the charger dock shows a fault LED on first insertion, pull the battery and wipe the gold contact strip with a dry cloth before reseating. The Kirisun dock needs a clean contact cycle to complete the BMS handshake before charging starts.

Why the DP405 cuts out mid-transmission on a new KB-760

A new Li-ion cell ships at storage voltage — typically 3.6–3.7V per cell, not full charge. When you key up on a fresh-out-of-box pack, the transmit current spike can pull the pack voltage below the BMS undervoltage threshold before the cells are fully charged. The BMS interprets this as a fault and shuts down output. A full charge cycle before first use brings each cell to 4.2V and gives the BMS enough headroom to handle the TX surge without tripping.

Bar indicator showing one fewer bar than expected after fitting KB-760

The Kirisun S760 and DP405 use a voltage-threshold bar indicator — each bar maps to a specific pack voltage band. A new cell at storage voltage sits in the second or third threshold band, so the radio displays fewer bars even though the pack is not depleted. This is not a fault with the cell. Charge the pack fully in the dock until the LED goes green, then reinsert — the indicator will read the correct band at 8.4V full charge.