Kenwood KNB-71L Replacement Battery 3.7V 1230mAh

Kenwood PKT-23 / ProTalk LT — 3.7V Li-ion Replacement Battery (KNB-71L / KNB-61L)

This 3.7V Li-ion cell at 1230mAh fits the Kenwood PKT-23, PKT-23K, PKT-03K, and ProTalk LT handheld transceivers. It replaces OEM part numbers KNB-71L and KNB-61L directly. The PKT-23 series uses an ultra-slim form factor, and this cell matches the original 54.50 × 35.10 × 6.30 mm envelope exactly.

• PKT-23 and ProTalk LT platform fit: These models share the same slim battery bay, contact layout, and BMS handshake protocol — one cell covers the full lineup without modification or adapter.
• Bench tested on actual hardware: We cycled this cell through charge and full transmit loads on a PKT-23 body. The BMS handled the PTT current spike cleanly and did not trip into overcurrent lockout during back-to-back keying.
• First insertion into the charger dock: If the dock LED shows a fault on first insertion, remove the battery, wipe the gold contact strip with a dry cloth, and reseat firmly. The PKT-23 platform requires a clean contact cycle to accept the new BMS handshake before charging begins.

Why the PKT-23 cuts out mid-transmission on a fresh KNB-71L

The PKT-23 draws a sharp current spike the moment PTT is pressed — RF output demands far more current than standby or receive mode. A new cell shipped at storage voltage (typically 3.6–3.75V) has enough charge to power the radio at idle but can sag below the BMS cutoff threshold under that transmit load. The BMS interprets the sag as a fault and disconnects the cell to protect it. Charge the battery fully to 4.2V before the first transmit session and the cutoff will not trigger.

Bar indicator showing one fewer bar than expected on a new cell

The PKT-23 bar display reads voltage thresholds — it does not track charge history. A cell at storage voltage reads as partially depleted because the voltage sits below the threshold the radio maps to a full bar. This is not a capacity fault in the replacement cell. Run a full charge cycle first; once the cell reaches 4.2V, the indicator will show the correct bar count.