Haaga 355 accu 18V Replacement Battery 3000mAh

Haaga 355 accu — 18V Li-ion Replacement Battery

This 18V 3000mAh (54Wh) Li-ion battery replaces the original pack on the Haaga 355 accu push sweeper. It fits the 355 accu directly and restores normal sweeper operation when the factory battery no longer holds a charge. Voltage and cell chemistry match the original specification.

• Haaga 355 accu compatibility: The 355 accu runs an 18V brushed motor driving the brush roller assembly. The replacement battery uses the same 18V cell configuration and connector format so the BMS handshake between pack and sweeper completes without fault codes.
• Bench tested on actual hardware: We ran the pack through charge and discharge cycles on an 18V load rig. The BMS held cell balancing correctly across the full discharge curve and triggered low-voltage cutoff cleanly before any cell dropped below the safe floor.
• Sweeper brush-load care: If the brush roller is clogged with debris, the motor draws significantly higher current at start-up. Clear the roller before each session — a blocked roller can repeatedly spike current draw and trip the BMS overcurrent protection on the new pack before the cells have completed a full cycle.

BMS cutoff on motor-start inrush with a new pack

On the first few uses, a fresh 18V Li-ion pack has its overcurrent threshold set conservatively until the BMS has logged actual motor inrush data from your specific sweeper. If the brush roller is partially obstructed, the motor pulls a larger inrush spike on start-up than the BMS expects. This can cause the pack to cut out immediately when the sweeper is switched on. Run the sweeper at light load — clear debris only, no heavy leaf piles — for the first two cycles to allow the BMS to calibrate against the motor's actual draw pattern.

Charger not recognising the pack after extended storage

Li-ion cells that have sat unused for several months can drop below 12–13V at the pack level, which is below the acceptance threshold most 18V chargers require before they begin a charge cycle. The charger may show a blinking red light or no response at all. A brief conditioning charge using a charger with a recovery or "wake" mode will bring the pack voltage up to the acceptance window — typically above 14V — at which point the standard charge cycle starts normally. If the charger has no recovery mode, connect the pack for 30 seconds, disconnect, and retry; some chargers re-poll on reconnection.