Ecovacs GOAT G1 Replacement Battery 18.5V 6400mAh

Ecovacs GOAT G1 Series — 18.5V Li-ion Replacement Battery (201-2201-0903)

This 18.5V 6400mAh Li-ion battery replaces the original pack in the Ecovacs GOAT G1, G1-800, GX-600, and GOAT G1 1600 robotic lawn mowers. It matches the OEM voltage rail and connector required by the mower's docking and BMS handshake. Capacity is 6400mAh (118.4Wh) — taken from product data, not estimated.

• GOAT G1 series and GX-600 compatibility: These models share the same 18.5V battery bay, dock charging circuit, and BMS communication protocol. One battery format covers all variants in the lineup.
• Bench tested on actual hardware: We cycled this pack through full charge and discharge on the GOAT G1 platform. The BMS handshake completed on the dock without error codes, and the blade motor drew cleanly through both start surge and sustained cutting load.
• Seasonal storage 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 before it ever starts a mowing run.

BMS cutoff under thick-grass and wet-grass blade load

The GOAT G1 blade motor pulls significantly more current when cutting dense or wet grass. If the instantaneous draw spikes past the BMS overcurrent threshold — typically during a tight turn into a thick patch — the BMS trips and the mower stops. This is a protection event, not a battery fault. Returning the mower to dock, allowing a short rest, and then restarting usually clears it. For recurring trips, lower the mowing schedule frequency or raise the cutting height to reduce blade load.

Charger shows fault after mower sat unused all winter

Li-ion cells self-discharge slowly over months of storage. If the GOAT G1 sat in a garage from October to March without a top-up charge, the pack voltage can fall below the charger's acceptance threshold — typically around 12V for an 18.5V pack. The dock sees the low voltage as an unsafe state and refuses to charge. To recover it, connect the original charger and leave it for 30–60 minutes without interruption; most chargers apply a low-current wake pulse before switching to full charge. If the dock still shows fault after 90 minutes, check cell voltage directly — if any cell reads below 2.5V, the pack needs replacement.