About this replacement
Makita BHR261 Series — 36V Li-ion Replacement Battery (BL3626)
This is a 36V, 3000mAh Li-ion replacement battery for the Makita BHR261 rotary hammer drill. It also fits the BHR261RDE, MUB360DZ, and MUH550DZ. Use the OEM part numbers BL3626, 194874-0, or BL3622A to confirm compatibility with your existing pack.
- BHR261 and MU-series compatibility: These models share the same 36V battery rail, slide-in connector, and BMS handshake protocol. The same pack slides into the rotary hammer and the hedge trimmer or brushcutter variants without adaptation.
- Bench tested on actual hardware: We ran this pack through repeated motor-start trigger cycles on a BHR261. The BMS handled inrush current correctly on each pull, held the voltage rail steady through sustained concrete drilling, and tripped thermal cutoff only when cell temperature reached the expected threshold.
- Break-in on first use: On first use, run the drill at half load — light concrete or masonry — for two full cycles before pushing maximum torque. This lets the BMS profile the motor's inrush draw and calibrate overcurrent thresholds before heavy-duty chiseling.
BMS overcurrent trip on motor-start inrush in the BHR261
Rotary hammer drills draw a sharp current spike the moment you pull the trigger — particularly in hammer mode. If the BMS hasn't profiled the motor yet, that inrush can exceed the default overcurrent threshold and trip the pack before the bit starts turning. A freshly installed replacement pack is most vulnerable on the first few pulls. Running two break-in cycles at reduced load lets the BMS log the inrush pattern and raise its threshold accordingly.
Charger shows blinking red on a new BL3626 pack after storage
Li-ion cells discharged below roughly 2.5V per cell will be rejected by most Makita chargers as a safety measure. A pack that sat in storage can drop below charger acceptance voltage. To recover it, check cell voltage with a multimeter — if the pack reads below 30V total, try a compatible charger with a recovery or wake-up mode. Once cells are back above the acceptance floor, the charger will recognise the pack and begin the normal charge cycle.