Kirisun FP-560 Replacement Battery 7.4V 1700mAh KBC-56C

Kirisun FP-560 / PT-560 — 7.4V Li-ion Replacement Battery (KBC-56C)

This 7.4V, 1700mAh lithium-ion battery replaces the Kirisun KBC-56C and KB-56C packs. It fits the FP-560 and PT-560 portable transceivers used in public safety, security, and commercial field operations. Capacity figure comes from the product data — 12.58Wh total energy.

• FP-560 and PT-560 platform fit: Both models share the same battery bay geometry, contact layout, and 7.4V nominal voltage rail. The BMS handshake protocol is identical across the pair, so one cell configuration covers both radios without modification.
• Bench tested on actual hardware: We cycled this pack through full charge and discharge on the FP-560 dock. The BMS held stable through PTT transmit spikes and did not trigger overcurrent cutoff under repeated keying at full RF output.
• First insertion on the Kirisun dock: If the dock LED flashes fault on first seating, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The dock requires a clean contact cycle to recognise the new BMS before charging begins — a loose or contaminated contact prevents this handshake entirely.

Why the FP-560 cuts out mid-transmission on a freshly inserted battery

A new lithium-ion cell ships at storage voltage — typically 3.6–3.7V per cell, giving roughly 7.2–7.4V at the pack terminals. When PTT is pressed, transmit current spikes sharply. If the pack voltage is close to the BMS low-voltage cutoff threshold, that spike is enough to trip the protection circuit and kill the transmission. This is not a faulty battery — it is the BMS doing its job before the pack has reached operating charge. Run the pack through one full charge cycle on the Kirisun dock before taking the radio into the field.

Bar indicator shows one fewer bar than expected after a full charge

The FP-560 uses a simple voltage-threshold bar display — each bar maps to a fixed voltage window, not a fuel gauge calculation. A new pack fresh off the charger may read one bar low if the dock terminated charge slightly early due to a minor contact impedance mismatch. Remove the battery, reseat it, and run another charge cycle. After the second full cycle, the resting voltage should sit at or above 8.2V and the indicator will reflect full charge correctly.