About this replacement
Hitachi DH 36DAL / DH36DL — 36V Li-ion 5000mAh Replacement Battery (BSL 3626)
This is a 36V Li-ion battery pack rated at 5000mAh (180Wh), built to fit the Hitachi DH 36DAL and DH36DL cordless drill/drivers. It replaces OEM part numbers BSL 3626, BSL 3636, and 328036. Voltage and connector match the original pack exactly.
- DH 36DAL and DH36DL compatibility: Both models run the same 36V battery rail, use the same slide-lock connector, and communicate with the pack over the same BMS data line. One replacement covers both tools without adapters or firmware differences.
- Bench tested on actual hardware: We cycled this pack through full charge and discharge runs on a DH 36DAL, monitoring BMS response to motor-start inrush spikes at full torque. The pack held the 36V rail within spec and the BMS did not trip under repeated high-draw trigger pulls.
- First-use load break-in on the DH 36DAL: Run the drill at half load — light fastening or low-torque drilling — for two full cycles before pushing maximum torque. This lets the BMS record the motor's inrush current signature and set overcurrent thresholds accurately before hard application use.
BMS overcurrent trip on trigger-pull inrush with the DH 36DAL
The DH 36DAL draws a sharp current spike the moment the trigger engages — this is normal motor-start inrush. A new pack coming out of storage has not yet profiled that spike, so its BMS overcurrent threshold may sit lower than the actual draw. If the pack cuts out the instant you pull the trigger, the BMS is tripping on that inrush before the motor reaches running current. Run two partial-load cycles first to let the BMS recalibrate, then return to full torque work. Most trip issues resolve without any charger intervention.
Charger not recognising the pack after extended storage
If a Li-ion pack sits unused for several months, cell voltage can drop below the charger's acceptance threshold — typically around 2.5V per cell. The Hitachi charger will blink an error or refuse to enter charge mode entirely when it sees voltage that low. The fix is a brief recovery charge: some chargers have a manual recovery mode; if yours does not, try a short burst from a compatible charger that supports low-voltage recovery, then return to the standard charger once the pack climbs above 3.0V per cell. Check individual cell voltage at the pack terminals — target at least 3.0V per cell before the main charger will accept it.