About this replacement
Bosch Cordless Garden Tools — 18V Li-ion Replacement Battery
An 18V 3000mAh Li-ion pack built to fit the Bosch 18V cordless garden tool range, including the Easy Spray 18V-100, Universal Pump 18V, Universal Fan 18V-1000, and Easy Drill 18V-40, among 109 additional models. Capacity sits at 54Wh — enough headroom for tools that cycle between burst and idle loads. The physical footprint matches the original slide-rail format at 116 x 80.3 x 65mm.
- Broad Bosch 18V compatibility: These models share the same 18V power rail, slide-mount connector, and BMS communication protocol — which is why one pack covers garden sprayers, fans, and drills from the same platform.
- Bench tested on actual hardware: We ran full charge/discharge cycles — the BMS held voltage steady under load and tripped the low-voltage cutoff cleanly without requiring a manual reset.
- First-charge tip for Li-ion packs: Charge fully before first use — this lets the BMS calibrate its state-of-charge tracking and avoids early capacity drift across the cell group.
Why the Easy Spray and Universal Pump draw differently from the same pack
Pump and sprayer tools pull current in short, high-demand bursts when pressurising the line, then drop to near-zero between strokes. Fan tools draw a steadier, lower continuous current. A 3000mAh pack handles both profiles because the BMS is rated for the peak draw of the pump without triggering an overcurrent fault during pressurisation cycles.
Tool powers on then cuts out immediately — here is what is happening
This is almost always a depleted cell triggering the BMS protection circuit, not a faulty tool. When one cell in the pack drops below the low-voltage threshold, the BMS disconnects output to protect the chemistry. The fix is a full, uninterrupted charge cycle — if the charger shows a fault light instead of completing, the pack has likely deep-discharged beyond recovery and needs replacing rather than recharging.