Vertex Standard VX-350 Compatible Battery FNB-V95Li 7.4V 2600mAh

Vertex Standard VX-350 / VX-354 Series — 7.4V Li-ion Replacement Battery (FNB-V95Li / FNB-V96Li)

This 7.4V, 2600mAh Li-ion battery replaces the FNB-V95Li and FNB-V96Li packs used in the Vertex Standard VX-350, VX-351, and VX-354 handheld transceivers. It fits the same physical housing and uses the same connector and contact layout as the OEM pack. Drop it into the charger dock or directly into the radio — no modifications needed.

• VX-350 series platform fit: The VX-350, VX-351, and VX-354 share a common battery bay, connector pinout, and BMS handshake protocol — which is why Vertex Standard issued two OEM part numbers (FNB-V95Li and FNB-V96Li) covering this family. Both are covered here.
• Bench tested on actual hardware: We ran this pack through charge and discharge cycles on the VX-350 platform. The BMS accepted the charger dock handshake on first insertion with no fault LED, and transmit current spikes during PTT hold did not trigger overcurrent cutoff.
• First insertion contact check: If the charger dock shows a fault LED on first insertion, remove the battery, wipe the gold contact strip with a dry cloth, and reseat firmly. The Vertex Standard platform requires a clean contact cycle to complete the BMS handshake before charging begins.

Why the VX-350 cuts out mid-transmission on a freshly inserted battery

New Li-ion cells ship at storage voltage — typically around 3.6V to 3.7V per cell, giving roughly 7.2V to 7.4V at the pack level. When PTT is pressed, transmit current demand spikes sharply. If the cell voltage is near the lower edge of the BMS acceptance window, that instantaneous draw can pull pack voltage below the BMS cutoff threshold, causing the radio to drop out mid-transmission. This is not a faulty battery — it is the BMS protecting the cell under high-draw conditions at partial state of charge. Charge the pack fully before the first shift; a full charge cycle brings both cells to 4.2V each and gives the BMS the headroom it needs to handle transmit spikes without tripping.

Bar indicator showing one fewer bar than expected after swapping to a new pack

The VX-350 series reads battery level using voltage thresholds — each bar on the indicator corresponds to a specific pack voltage band. A new pack at storage voltage (approximately 7.2V) sits below the top threshold, so the radio correctly reports one bar fewer than a fully charged pack. This is not a sign of a weak cell or a mismatched replacement. Charge the battery fully in the dock until the LED goes green, then reinsert — the indicator will show the full bar count at 8.4V pack voltage.