Flymo 1200R 18V Replacement Battery 2500mAh Li-ion

Flymo 1200R — 18V Li-ion Replacement Battery

This 18V 2500mAh Li-ion battery fits the Flymo 1200R cordless rotary lawn mower, including the 2013 and 2014 model years. It slots directly into the mower's battery bay and connects to the same charging circuit as the original pack. Voltage and capacity match the factory specification at 18V and 2500mAh (45Wh).

• 1200R compatibility: All listed 1200R variants share the same 18V battery bay, connector pinout, and BMS handshake protocol. A single cell configuration covers the full model range without modification.
• Bench tested on actual hardware: We ran this pack through the 1200R's startup cycle and monitored BMS response under simulated blade-load conditions. The protection circuit held correctly at both low-voltage cutoff and overcurrent thresholds during motor inrush.
• Seasonal storage tip: Before the first mow of spring, 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 the mower completes a single pass.

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

The 1200R blade motor draws significantly more current through dense or wet grass than on a dry, short lawn. If the BMS reads a current spike beyond its overcurrent threshold — typically caused by the blade bogging down — it cuts the pack to protect the cells. This shows as a sudden full power-off, not a gradual fade. Let the pack rest for 30 seconds, then resume on a lower-resistance section of lawn to reset the protection circuit.

Charger refusing to accept the pack after winter storage

Li-ion cells left in storage without a top-up charge can discharge below the minimum acceptance voltage — typically around 2.5V per cell. Most Flymo chargers will not initiate a charge cycle on a pack in this state and show a fault light instead. To recover the pack, some chargers have a recovery or boost mode; consult your charger's indicator sequence. If the charger accepts the pack in recovery mode, charge it fully before the first mow and check resting voltage sits above 17V before use.