About this replacement
Wolf Garten Power 37 / Power 40 Series — 36.5V Li-ion Replacement Battery (4949066)
This is a 36.5V 7500mAh Li-ion replacement battery for the Wolf Garten Power 37, Power 40, Hybrid Power 37, and Hybrid Power 40 cordless lawn mowers. It matches the OEM part numbers 4949066, PACK 1, and 4937065. Capacity is 273.75Wh — same voltage rail and connector as the original pack.
- Power 37 and Power 40 platform compatibility: All four fit models — standard and Hybrid variants — share the same 36.5V bus, battery connector, and BMS handshake protocol. One pack covers the full lineup without modification.
- Bench tested on actual hardware: We ran this pack through blade-start inrush and sustained cutting load cycles. The BMS held under repeated high-draw starts and balanced cells correctly across the full discharge curve.
- Seasonal storage care: Before the first mow of the season, bring the battery indoors overnight if air temperature is below 10°C. Cold Li-ion cells have elevated internal resistance, and the blade motor's inrush current can trip the BMS on a cold pack before the first cut completes.
BMS cutoff when mowing thick or wet grass
Wet or dense grass dramatically increases blade drag, which spikes motor draw well above normal cutting load. If that spike exceeds the BMS current threshold, the pack shuts down as a protection response — not a battery fault. Let the mower sit for five minutes so the BMS thermal sensor resets, then resume. Mowing in overlapping passes through thick sections keeps draw below the trip point.
Charger showing a fault light after the mower sat unused all winter
A pack left discharged over winter can drop below the charger's acceptance voltage — typically around 30V on this platform. Most Wolf Garten chargers read this as a fault and refuse to charge. Some chargers have a recovery or wake-up mode; connect the pack, wait two minutes without interrupting, and the charger may begin a slow pre-charge cycle. If the charger accepts the pack and begins charging normally, allow a full charge cycle before use.