About this replacement
Husqvarna AM430X / AM440 / AM550 Series — 18V Li-ion Replacement Battery (580 68 33-01)
This 18V 5200mAh (93.6Wh) Li-ion battery replaces the original pack in the Husqvarna Automower AM430X, AM440, AM550, and compatible models in the Automower range. It uses the same OEM voltage rail and connector format as the factory battery, so the mower's docking and charging cycle runs without modification. Capacity figures come from product data, not estimated values.
- AM430X, AM440, AM550 and extended compatibility: These models share the same 18V battery bay, connector pinout, and BMS handshake protocol. That common platform means one battery fits across the range without adapters or firmware changes.
- Bench tested on actual hardware: We cycled this pack through full charge and discharge on an AM430X chassis. The BMS engaged correctly at both the low-voltage cutoff and the charge-termination threshold. Cell balancing across the pack stayed within spec throughout the test.
- Seasonal storage before first spring use: Before first use 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 mower completes its first row.
BMS cutoff under thick-grass and wet-grass blade load
The AM430X blade motor draws significantly more current when cutting dense or wet grass. If that inrush current exceeds the BMS threshold — typically because the pack is also cold or partially discharged — the BMS trips as a protection event, not a fault. The mower parks itself and waits for a reset via the docking station. Keeping the pack above 30% state of charge before sending the mower into heavy growth reduces the frequency of these trips.
Charger refusing to accept the pack after winter garage storage
Li-ion cells left in a garage over winter can self-discharge below the charger's acceptance voltage — typically under 12V at pack level. Most Automower base stations will not initiate a charge cycle if they read the pack as critically low, showing a fault light instead. Place the battery in a warmer environment (above 15°C) for two hours, then try docking again. If the charger still shows a fault after warming, the cells may have discharged past recovery and a replacement pack is needed.