About this replacement
AL-KO Gardening Tool — 18V Li-ion Replacement Battery
This 18V, 5000mAh Li-ion battery replaces the original AL-KO pack across the Comfort GT, PS, HTA, and related 18V cordless gardening tool lines. At 90Wh, it matches the voltage rail and capacity tier these tools ship with from the factory. Fits the Comfort GT 1825, Comfort PS 181, Comfort HTA 1845, Comfort PS 1815, and 27 additional AL-KO models.
- Multi-model AL-KO 18V compatibility: The GT, PS, and HTA model lines share the same 18V power rail, connector footprint, and BMS communication protocol — one battery works across all of them without adapters or modifications.
- Bench tested on actual hardware: We ran full charge/discharge cycles — the BMS held voltage steady under load and triggered the low-voltage cutoff cleanly without false stops or thermal trips.
- First charge on a new Li-ion pack: Run the battery through two full charge cycles before heavy use — this lets the BMS calibrate cell balancing accurately and helps the state-of-charge readout stabilise.
How the 5000mAh capacity affects AL-KO 18V tool performance
Capacity determines how long the cell stack can sustain current draw before hitting the low-voltage cutoff — not how hard the tool works. AL-KO's 18V gardening tools pull variable current depending on load, so a 5000mAh pack gives more headroom than the stock 2000–2500mAh packs often bundled at retail. The BMS inside this battery limits peak discharge to protect both the cells and the tool's motor controller.
Tool cuts out under load — what's happening and how to fix it
If the tool shuts off mid-task but restarts after a short pause, the BMS is hitting its overcurrent threshold — not a faulty battery. This usually happens when the tool is forced through dense material too quickly, spiking current draw beyond the BMS's set limit. Let the pack rest for 60 seconds to allow the protection circuit to reset. Reduce load pressure on the next pass and the cutout should stop recurring.