About this replacement
Kenwood TK-2200 / TK-2202 Series — 7.2V Ni-MH Replacement Battery (KNB-29N / KNB-30N)
This is a 7.2V, 1800mAh Ni-MH battery for the Kenwood TK-2200, TK-2202, TK-2206, TK-2207, and over 86 compatible models. It replaces OEM part numbers including KNB-29N, KNB-30N, KNB-53N, and RAD0148. The pack slots directly into the radio's battery bay and communicates with the KSC-35 and KSC-31 charger docks.
- TK-2200 series compatibility: These models share a common 7.2V Ni-MH voltage rail, the same battery bay footprint, and identical contact geometry. The BMS handshake protocol is consistent across the TK-2200, TK-2202, TK-2206, and TK-2207 platforms, which is why a single pack covers such a wide model range.
- Bench tested on actual hardware: We cycled this pack through charge and discharge on the KSC-35 dock and monitored the BMS across PTT transmit events. The pack held 7.2V under sustained transmit load and the BMS did not trip on repeated key-ups.
- First insertion into the KSC-35 dock: If the charger LED blinks fault on first insertion, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The KSC-35 platform requires a clean contact cycle to accept the new BMS handshake before it will begin charging.
Why the TK-2200 cuts out mid-transmission on a new battery
PTT on the TK-2200 pulls a sharp current spike to drive the RF output stage. If the pack is at storage voltage — typically 6.8V to 7.0V — the BMS reads that spike as an overcurrent event and shuts the output down before the transmission completes. This is not a faulty pack. Running one full charge cycle on the KSC-35 brings the cells to nominal voltage and eliminates the BMS trip on transmit.
Bar indicator shows one fewer bar than expected after fitting a new pack
The TK-2200 uses voltage-threshold readings to drive its bar indicator — it is not a fuel gauge chip. A new pack shipped at storage voltage sits below the radio's top-bar threshold, so the display shows one or two bars even on a fresh cell. This is a voltage reading, not a capacity fault. Charge the pack fully on the KSC-35 and the indicator will step up to the correct level at full charge voltage.