Yaesu FNB-V131Li VX-230 7.4V Replacement Battery 1600mAh

Yaesu VX-230 / VX-231 Series — 7.4V Li-ion Replacement Battery (FNB-V131Li)

This is a 7.4V, 1600mAh Li-ion replacement battery for the Yaesu VX-230, VX-231, VX-231L, and VX-234 handheld transceivers. It replaces OEM part numbers FNB-V131Li and FNB-V132Li. The cell matches the original voltage rail and BMS communication protocol required by these radios.

• VX-230 / VX-231 / VX-231L / VX-234 fitment: All four models share the same battery bay geometry, gold contact strip layout, and 7.4V power rail. The BMS handshake logic is identical across this Vertex Standard series, so one pack covers the full group without modification.
• Bench tested on actual hardware: We cycled this pack through full charge and discharge on a VX-231 unit. The BMS handled PTT transmit current spikes without triggering overcurrent cutoff, and the charger dock accepted the pack without a fault LED on the first insertion cycle.
• First-insertion contact check on Vertex Standard docks: If the charger dock shows a fault or blink pattern on first insertion, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The VX-series dock requires a clean contact cycle to complete the BMS handshake before it begins charging.

Why the VX-230 bar indicator reads low on a new FNB-V131Li pack

New Li-ion cells ship at storage voltage, typically around 3.7V per cell, not at full charge. The VX-230 uses a voltage-threshold bar indicator, so a pack at storage voltage will display one or two bars even though the cell is healthy. Run the pack through one full charge cycle in the dock before judging capacity. After a complete charge, the indicator should read full bars at rest with the radio on.

VX-231 drops to reduced TX power mid-shift on a replacement pack

Sustained RF transmission draws significantly more current than standby or receive modes. If the pack's cells have elevated internal impedance — common after extended storage — voltage sags under that load and the radio's protection circuit steps down transmit power to stay within operating range. This is not a radio fault. Fully charge the pack, then run two or three full charge-discharge cycles to condition the cells. Check resting voltage after a full charge — it should sit at or above 8.2V before the radio is powered on.