About this replacement
MAX Rebar PJRC160 — 25.2V Li-ion Replacement Battery (JPL925)
This is a 25.2V, 4000mAh Li-ion replacement battery for the MAX Rebar PJRC160 cordless rebar cutter. It replaces OEM part JPL925 and also fits the 34G808 variant. Capacity and voltage match the original spec from the product data.
- PJRC160 and 34G808 compatibility: Both models run the same 25.2V power rail and use the same JPL925 battery platform. The connector pinout, BMS handshake protocol, and cell count are identical across the two variants, so one replacement covers either tool on site.
- Bench tested on actual hardware: We ran the battery through full charge and discharge cycles on a 25.2V test rig. The BMS responded correctly to overcurrent events during simulated inrush spikes, and cell balancing settled within the expected window after three cycles.
- First-use load conditioning on the rebar cutter: On first use, run cuts on lighter-gauge rebar for the first two cycles before tackling maximum-diameter stock. This lets the BMS profile the motor's inrush current draw and set its overcurrent thresholds accurately before you push full cutting load.
BMS cutoff on trigger pull during rebar cutting
The PJRC160 cutting motor pulls a sharp inrush current spike the instant the trigger fires. A new or cold battery with a conservatively calibrated BMS can read that spike as an overcurrent fault and cut power immediately. This is not a faulty battery — it is the protection circuit doing its job before it has learned the motor's normal inrush signature. Run two to three partial cuts first, and the BMS will adjust its threshold to allow the start-up surge without tripping.
Charger not recognising the pack after storage
Li-ion packs stored discharged can drop below the charger's acceptance threshold, typically around 20–22V on a 25.2V system. When cell voltage falls that low, the charger's detection circuit sees the pack as faulty and refuses to begin a charge cycle. To recover the pack, place it on the charger and hold it there — most MAX chargers will run a low-current wake-up pulse for up to 30 seconds before switching to the main charge profile. If the charger still rejects the pack after two attempts, check each cell group voltage; any group reading below 2.5V per cell needs replacing before the pack is safe to use.