Husqvarna AM430X Replacement Battery 18V 6800mAh

Husqvarna AM430X / AM550 Series — 18V Li-ion Replacement Battery (580 68 33-01)

This 18V 6800mAh Li-ion battery replaces the original pack in Husqvarna robotic mowers including the AM430X, AM440, AM550, and Automower 430X. It matches the OEM voltage rail and connector, so the mower's dock charging and BMS handshake work without modification. Capacity is 6800mAh (122.4Wh), sourced against OEM specs.

• AM430X / AM440 / AM550 platform fit: These models share the same 18V battery bay, connector pinout, and BMS communication protocol. One pack covers all three, and the mower's base station charges it the same way as the original.
• Bench tested on actual hardware: We cycled this pack through blade-motor inrush loads on the AM430X platform. The BMS held under repeated start sequences and handled regenerative braking events from direction changes without triggering a fault cutoff.
• Spring recommission tip: Before the first mow of the season, bring the battery indoors overnight if temperatures are below 10°C. Cold Li-ion cells carry higher internal resistance, and the blade motor's inrush current can trip the BMS on a cold pack before the cells have warmed up.

BMS cutoff under thick grass and wet-lawn blade load

When the AM430X crosses dense or waterlogged grass, the blade motor draws significantly more current than on dry, short turf. If that draw exceeds the BMS protection threshold — typically triggered by a sustained current spike rather than a steady load — the pack cuts out to protect the cells. This usually appears as the mower stopping mid-zone and returning to base with a battery fault code. Lowering the mowing height in small increments across heavy-growth areas reduces peak blade load and keeps current draw within the BMS window.

Charger not accepting the pack after winter storage

Li-ion cells that self-discharge below roughly 2.5V per cell over winter drop under the charger's minimum acceptance voltage. The Husqvarna base station reads this as a fault and refuses to begin a charge cycle. Place the battery on the dock and leave it connected — some chargers apply a trickle pre-charge to recover packs from this state over 30 to 60 minutes before switching to normal charge. If the dock still shows a fault after an hour, check cell voltage directly; anything below 14V across the full pack indicates a cell has dropped too far to recover.