Worx WA3127 18V Ni-MH Replacement Battery 2000mAh

Worx WG150s / WG152 / WG250 / WG541 — 18V Ni-MH Replacement Battery (WA3127)

This is an 18V, 2000mAh Ni-MH replacement battery carrying OEM part number WA3127. It fits the Worx WG150s, WG152, WG250, and WG541 cordless string trimmers and edgers. Voltage and cell format match the original pack exactly.

• WG150s / WG152 / WG250 / WG541 platform fit: These models share the same 18V battery rail, slide-in connector, and BMS handshake protocol — one pack covers the whole family without adapter hardware or firmware conflicts.
• Bench tested on actual hardware: We cycled this pack through simulated trimmer load profiles on the bench. The BMS handled motor-start inrush without tripping overcurrent and held voltage within spec across the discharge curve.
• Ni-MH break-in on first use: Ni-MH cells need two to three full charge-discharge cycles before reaching rated capacity. Run the trimmer at a moderate load through a complete discharge each time — the cells will reach full 2000mAh output by cycle three.

Charger blinking red on WA3127 pack after storage

Ni-MH packs sitting unused for several months self-discharge below the charger's acceptance threshold — typically under 10V on an 18V pack. The charger reads this as a fault and blinks red instead of starting a charge cycle. Most Worx chargers include a recovery mode: hold the pack in the charger for 10–15 minutes and the unit will trickle-charge the cells up to acceptance voltage before switching to normal charge. If the charger does not recover the pack within 20 minutes, check terminal voltage directly — anything above 9V is recoverable with a compatible NiMH recovery charger.

Trimmer bogs or loses power mid-cut through thick grass

Sustained high load through dense grass forces the motor to draw continuous peak current, which heats both the motor housing and the battery cells simultaneously. Ni-MH cells have higher internal resistance than Li-ion, so voltage sag under load is more pronounced — particularly as the pack ages. The BMS will cut power if cell temperature exceeds its thermal threshold, causing the tool to stop mid-cut. Let the pack cool for five minutes, then check resting voltage: if it reads above 16V at rest, the cutoff was thermal, not a capacity failure — the pack will resume normally once cooled.