About this replacement
Wolf Garten Power 37 / Power 40 Series — 36.5V Li-ion Replacement Battery (4949066)
This 36.5V, 5000mAh Li-ion battery replaces the original pack on Wolf Garten Power 37, Power 40, Hybrid Power 37, and Hybrid Power 40 cordless lawn mowers. It matches the OEM voltage rail and connector used across the 36V Power platform. Capacity is 5000mAh (182.5Wh), sourced direct from the product specification.
- Power 37 / Power 40 platform fit: All four models — Power 37, Power 40, Hybrid Power 37, Hybrid Power 40 — share the same 36V battery bay, connector pinout, and BMS handshake protocol. One pack covers the full range.
- Bench tested on actual hardware: We cycled this pack through blade-motor start loads and mid-cut draw spikes. The BMS held stable under repeated high-inrush events, and cell balancing completed correctly at end of charge.
- Seasonal storage care: Before the first mow of spring, 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 on thick grass and wet-grass blade load
The Power 37 blade motor draws a sharp inrush current each time it bites into dense or wet grass. If that spike exceeds the BMS threshold — typically triggered by repeated heavy cuts in succession — the pack cuts power to protect the cells. This is not a battery fault; it is the BMS doing its job. Let the mower sit for five minutes to allow the BMS thermal sensor to reset, then resume cutting at a slightly faster walking pace to reduce dwell time per blade rotation.
Charger shows fault light after mower sat unused all winter
Li-ion packs left in storage self-discharge slowly over months. If the cell voltage drops below roughly 2.5V per cell, most chargers refuse to begin a charge cycle — the fault light comes on immediately. Place the pack on the charger and leave it connected for up to 30 minutes; some chargers run a low-current recovery pulse before switching to normal charge mode. If the fault light clears and charging begins, the pack is recovering. If it does not clear after 30 minutes, the cells have dropped too far and the pack needs replacement.