About this replacement
Kenwood TK-2200 Series — 7.2V Ni-MH Replacement Battery (KNB-29N / KNB-30N)
This is a 7.2V 2500mAh Ni-MH battery for the Kenwood TK-2200, TK-2202, TK-2206, TK-2207, and over 80 compatible models in the same series. It replaces OEM packs including KNB-29N, KNB-30N, KNB-53N, and RAD0148. The pack slots into the same battery bay and connects through the same multi-pin contact strip used across the TK-2200 platform.
- TK-2200 series platform fit: These models share a common 7.2V battery bay, identical contact geometry, and the same BMS handshake protocol. A pack built to this spec will seat and communicate correctly across all listed variants without modification.
- Bench tested on actual hardware: We ran this pack through full charge and PTT-cycle discharge on a TK-2202. The BMS handled transmit current spikes without tripping, and the charger dock accepted the handshake on first insertion with no fault LED.
- First-cycle contact prep on Kenwood docks: If the KSC-35 or KSC-31 dock shows a fault LED on first insertion, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The dock requires a clean contact cycle to read the BMS before charging begins.
Why the TK-2200 cuts out mid-transmission on a new Ni-MH pack
Ni-MH cells ship at storage voltage — typically around 6.0–6.4V for a 7.2V pack. When you press PTT, the radio draws a sharp transmit current spike that can push a storage-voltage cell below the BMS low-voltage cutoff threshold. The radio reads this as a depleted pack and drops the transmission. This is not a fault with the battery. Charge the pack fully in the dock before first use in the radio, and the cutout stops.
Bar indicator showing one fewer bar than expected after a full charge cycle
The TK-2200 uses a simple voltage-threshold bar display — each bar maps to a specific pack voltage under load. A new Ni-MH cell needs two to three full charge-discharge cycles before it reaches full charge acceptance. On the first cycle, the pack may peak slightly below the voltage threshold for the top bar. Run two complete cycles through the KSC-35 dock, and the indicator will read correctly at the voltage the radio expects to see.