About this replacement
Makita 4334D Series — 18V Ni-MH Replacement Battery (1822)
This is an 18V, 3000mAh Ni-MH replacement battery for the Makita 4334D cordless jigsaw series. It fits the 4334D, 4334DWA, 4334DWAE, 4334DWD, and over 70 additional Makita 18V tools sharing the same slide-rail pack format. Compatible OEM part numbers include 1822, 1823, 1833, 1834, 1835, PA18, and related variants.
- 18V slide-rail platform compatibility: These Makita models share the same 18V slide-in connector block, cell count, and BMS handshake protocol. The charger communicates with the pack via the signal terminal — the same terminal and pinout applies across the full 4334D family, which is why one pack fits the entire range.
- Bench tested on actual hardware: We ran this pack through charge and discharge cycles on a Makita 18V platform, monitoring the BMS response at trigger-pull inrush. The protection circuit handled motor-start current spikes without nuisance tripping and held voltage within expected rails under sustained cutting load.
- Ni-MH break-in on jigsaw load: On first use, run two full light-to-moderate cutting cycles before pushing maximum stroke speed or cutting through thick hardwood. Ni-MH cells reach stable capacity after a few full charge-discharge cycles — the BMS also uses this period to calibrate overcurrent thresholds against the jigsaw motor's inrush signature.
BMS cutoff on jigsaw motor-start inrush surge
When you pull the trigger on the 4334D, the motor draws a short burst of current well above its running draw — this is inrush current as the armature spins up from zero. A new or recently stored Ni-MH pack may trip the BMS overcurrent threshold during this spike because the pack hasn't yet profiled the motor load. If the tool stops immediately on trigger pull but recovers after a second attempt, that's the BMS resetting after the trip. Running two break-in cycles at moderate speed lets the protection circuit learn the motor's startup signature and stop false-tripping.
Charger blinks red and won't accept the new pack
Makita 18V chargers run a voltage check before starting a charge cycle — if the pack sits below roughly 10V, the charger rejects it as a fault rather than attempting recovery. A pack shipped in storage discharge can sit at this level after time in transit or on a shelf. To recover it, briefly connect the pack to a compatible tool and pull the trigger a few times — this nudges cell voltage up enough for the charger to register it as a valid pack. Once the charger accepts it and goes into normal charge mode, run a full cycle to at least 21.6V before use.