About this replacement
Husqvarna Automower 265ACX Series — 22.2V Li-ion Replacement Battery (578 84 87-02)
This 22.2V 6800mAh Li-ion battery replaces the original power pack in the Husqvarna Automower 265ACX, 265ACX G2-2, and 2012–2014 model variants. It slots directly into the mower's battery bay and connects to the onboard BMS via the same multi-pin interface as the factory unit. Capacity is 6800mAh (150.96Wh) — sourced to match the original cell specification, not upsized or downgraded.
- 265ACX platform fit: All 265ACX variants share the same 22.2V battery rail, connector pinout, and BMS handshake protocol. That means the same cell pack covers the base model, G2-2, and the 2012 and 2014 production runs without any wiring or firmware difference.
- Bench tested on actual hardware: We ran this pack through charge cycles and simulated blade-motor inrush loads. The BMS held cutoff thresholds within spec, and cell balancing completed correctly across the 6-cell series string on each cycle.
- Spring recommission tip: Before first use of the season, bring the battery indoors overnight if temperatures are below 10°C. Cold Li-ion cells have higher internal resistance, and the blade motor's inrush current can trip the BMS on a cold pack — even if the charge level reads full.
BMS cutoff on thick-grass or wet-grass blade load
The Automower 265ACX blade motor draws a short inrush spike every time it bites into dense or wet grass. If the battery's BMS detects that spike as an overcurrent event — common on a worn or ageing pack — it cuts power to protect the cells. A new pack with healthy internal resistance handles the same spike without tripping. If cutouts continue after fitting a new battery, check the blade disc for debris and confirm the cutting height is not set too low for current grass conditions.
Charger showing fault after the mower sat in storage all winter
Li-ion cells self-discharge slowly over several months. If the Automower sat in an unheated garage through winter without a maintenance charge, the pack voltage may have dropped below the charger's acceptance threshold — typically around 18V for a 22.2V 6-cell pack. The charger sees a voltage that looks like a damaged or shorted cell and refuses to initiate a charge cycle. At that point the battery needs replacement; a pack that has sat in deep discharge for weeks has likely suffered permanent cell damage that a charge cycle will not reverse.