Matrix 18V AK 18-1-Li Replacement Battery 2000mAh Li-ion

Matrix AK 18-1-Li — 18V Li-ion Replacement Battery (120.300.650)

This is an 18V 2000mAh Li-ion replacement battery for the Matrix AK 18-1-Li cordless tool platform. It fits Matrix 18V drills, impact drivers, circular saws, and other tools that accept the AK 18-1-Li pack. Voltage and capacity match the OEM spec — 18V nominal, 36Wh total energy.

• AK 18-1-Li platform compatibility: Matrix 18V tools share a common battery rail and connector across the AK 18-1-Li lineup. The BMS on this pack communicates with the tool's controller using the same signal line as the original, so the tool recognises the pack without modification.
• Bench tested on actual hardware: We ran this pack on a Matrix 18V drill and circular saw under load. The BMS held the output rail steady through repeated trigger pulls and cleared overcurrent events without latching into fault mode.
• Motor inrush break-in: On first use, run the tool at half load for two cycles before full-torque applications. This lets the BMS log the motor's inrush current signature and set overcurrent thresholds accurately before you push the tool hard.

BMS cutoff on drill and saw motor-start inrush surge

Every time you pull the trigger, the motor draws a spike of current — often three to five times the running current — for the first fraction of a second. If the BMS has not yet profiled the motor, it can read that spike as a fault and cut the output rail instantly. This is not a dead battery — it is the overcurrent protection doing its job with an incomplete current map. Running the tool through two half-load cycles before full use gives the BMS enough data to distinguish a normal start from a true fault. After the break-in cycles, cold-start cutouts on trigger pull should stop.

Charger not recognising the pack after storage

Li-ion cells self-discharge during storage. If the pack voltage drops below the charger's acceptance threshold — typically around 10V on an 18V pack — the charger refuses to start a charge cycle and shows a blinking or red indicator. The cells are not dead; they are just below the entry window. Use a compatible Li-ion charger with a recovery or "wake" mode, or apply a short manual top-up at a low rate to bring the pack above 12V. Once above the threshold, insert the pack into the Matrix charger and it will begin a normal charge cycle.