Icom BP-283 Two-Way Radio Compatible Battery 7.4V 2500mAh

Icom IC-F3400 Series — 7.4V Li-ion Replacement Battery (BP-283)

This 7.4V, 2500mAh Li-ion battery replaces the BP-283, BP-284, and BP-303 packs used in the Icom IC-F3400 series portable transceivers. It fits the IC-F3400, IC-F3400D, IC-F3400DP, and IC-F3400DPS, along with 18 additional variants in the same family. Capacity is rated at 18.5Wh and voltage is the same 7.4V nominal as the original pack.

• IC-F3400 series compatibility: All listed variants share the same 7.4V power rail, connector footprint, and BMS handshake protocol. The BP-283, BP-284, and BP-303 are interchangeable across this platform because Icom standardised the pack interface across the F3400 lineup — including encrypted D and DPS variants.
• Bench tested on actual hardware: We cycled this pack on the IC-F3400 bench unit under simulated PTT transmit loads. The BMS handled the current spike at keying without tripping, and the radio accepted the pack without displaying a fault indicator on the status screen.
• First insertion into the charger dock: If the dock shows a fault LED on first insertion, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The IC-F3400 dock requires a clean contact cycle to complete the BMS handshake before it begins charging — a partial contact on first seat is the most common cause of this.

Why the IC-F3400 cuts out mid-transmission on a new BP-283

A new Li-ion pack ships at storage voltage — typically around 3.7V per cell, giving roughly 7.4V at the terminals. That is enough to power the radio in receive mode, but the transmit current spike when PTT is pressed can cause the BMS to interpret the sudden draw as an overcurrent event and cut the output. This is not a faulty pack. The cell chemistry needs one or two full charge-discharge cycles before the BMS settles its overcurrent threshold to match the radio's actual transmit profile. Charge the pack fully before field use — at least one complete charge from the dock — then key up on low power first to let the BMS calibrate to the transmit load.

Bar indicator showing one fewer bar than expected after inserting the new pack

The IC-F3400 reads battery level by voltage threshold — it has no fuel gauge chip, just a simple voltage-to-bar mapping. A new pack at storage voltage reads lower than a fully charged pack, so the radio may show two or three bars instead of four immediately after insertion. This is not a capacity problem. Charge the pack fully in the dock until the charge indicator goes green, then reinsert — the radio will read the correct voltage and display the full bar count. If it still reads low after a full charge, check that the dock contacts are clean and making firm contact with the gold strip on the pack.