About this replacement
Kenwood P25 / TK-5230 / TK-5330 / TK-5430 — 7.4V Li-ion Replacement Battery (KNB-L1)
This 7.4V, 2800mAh lithium-ion battery replaces the KNB-L1, KNB-L2, KNB-L3, KNB-N4, and related OEM packs for the Kenwood P25, TK-5230, TK-5330, and TK-5430 series two-way radios. It fits directly into the radio body and connects via the same contact array as the original. No tools or adapters required.
- P25 and TK-5000 series fit: These models share a common 7.4V battery bay, contact pitch, and BMS handshake protocol — so one pack covers the full platform without modification.
- Bench tested on actual hardware: We ran the pack through charge and discharge cycles on a TK-5330. The BMS responded correctly to transmit-current spikes during PTT, held voltage within spec under sustained RF output, and showed no overcurrent faults at the dock.
- First insertion on the charger dock: If the dock shows a fault LED on first seating, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The Kenwood P25 platform requires a clean contact cycle to complete the BMS handshake before charging begins.
Why the TK-5330 drops to reduced TX power mid-shift on a new battery
The TK-5330 monitors pack voltage in real time and steps down transmit power if voltage sags below a set threshold during high-draw RF output. A new cell shipped at storage voltage — typically around 3.7V per cell — sits close to this threshold before a full charge cycle. The radio interprets that sag as a weak pack and throttles output. One complete charge cycle before first use brings cell voltage to 4.2V per cell and eliminates the sag response.
Bar indicator showing one fewer bar than expected after fitting this pack
Kenwood P25-series radios use voltage-threshold bar indicators — each bar represents a voltage band, not a percentage. A pack arriving at storage voltage will read one bar low even though the cell capacity is intact. This is not a fault with the cell. Seat the pack in the charger, let it complete a full charge cycle, and the indicator will step up to the correct bar count at 8.4V fully charged.