Fimap e-Spray 18V Replacement Battery 4000mAh YLD02

Fimap e-Spray — 18V Li-ion Replacement Battery (230390)

This is an 18V 4000mAh Li-ion replacement battery for the Fimap e-Spray electric sprayer. It fits the e-Spray's original battery slot and powers the pump mechanism used in professional cleaning and disinfection tasks. Voltage is 18V; capacity is 4000mAh (72Wh).

• e-Spray pump compatibility: The e-Spray runs its pump motor off an 18V rail with a direct BMS handshake — the charger and sprayer both verify cell state before allowing current flow. A mismatched BMS profile trips the protection circuit on pump start, so cell count and voltage topology must match the OEM spec exactly.
• Bench tested on actual hardware: We cycled this pack through repeated pump-start inrush events and monitored the BMS overcurrent threshold. The protection circuit held across all start cycles without nuisance tripping, and cell voltage balanced correctly at full charge.
• Pump motor cycling tip: On the first two uses, run the sprayer at low-pressure settings before switching to full pump load. This lets the BMS log the motor's inrush current signature and set its overcurrent threshold accurately before you push the pump hard.

BMS cutoff on e-Spray pump motor start surge

When the e-Spray pump starts, the motor draws a short inrush spike — often two to three times the steady-state current. A BMS with a tight overcurrent threshold interprets that spike as a fault and cuts the output before the pump even reaches operating pressure. This is more common with a new or freshly charged pack where the BMS has not yet profiled the motor load. If the sprayer shuts off immediately on trigger pull, charge the pack to full (18V resting), then attempt a slow-start at low pressure to allow the BMS to calibrate.

Charger not recognising the pack after storage

Li-ion chargers use a minimum acceptance voltage — typically around 10–12V for an 18V pack — before entering the main charge cycle. A battery stored discharged for several months can drop below that threshold, causing the charger to show a fault or simply do nothing. The fix is a brief recovery charge using a bench supply set to 15V at 0.5A to bring the cells back above the acceptance floor. Once the pack reads above 12V, place it back on the standard charger and it should accept a normal charge cycle.