12V EGO CHT2001E Replacement Battery 2500mAh Li-ion

My EGO grass shears cut fine for a few passes then slow down and feel weak — new battery, same problem

On light-draw tools like these shears, the most common cause of mid-use slowdown isn't the battery failing — it's the blade resistance climbing because resin, sap, or grass fibre is binding the mechanism and forcing higher current draw than the 12V cell is rated to sustain comfortably. The battery's protection circuit then throttles output to stay within safe limits. Clean both blade sets thoroughly, including the pivot gap on the shrub attachment, and test again with a freshly charged pack. If slowdown only happens on the shrub blade and not the grass blade, the 8mm gap is the likely culprit — clear it and retest.

Swapped to the grass trimmer attachment and now the shears won't turn on at all — just clicks once

A single click with no blade movement usually means the battery made contact but immediately tripped the overcurrent protection, which happens when the trimmer blade is slightly misseated and the motor tries to start under a mechanical load it can't overcome. Remove the attachment completely, check the connector pins on both the tool body and the battery for debris or bent contacts, reseat the grass blade until it clicks fully into position, and try again. If it starts normally after a clean reseat, the attachment wasn't fully locked — that's the fix.

Left the EGO shears in the shed all winter and the battery won't charge now — charger just sits there doing nothing

A 12V lithium-ion cell that has self-discharged below roughly 2.5V per cell over a long storage period will often be rejected by the charger entirely — it reads as a fault condition, not a dead battery, so the charger shows no activity rather than a fault light. We've seen this on small-capacity 12V packs left unused for more than two or three months. Try leaving the battery connected to the charger for 20–30 minutes anyway, since some chargers will attempt a recovery trickle before displaying status. If there's still no response and no LED change at all after that window, measure the pack voltage at the terminals — anything below 9V on a 12V Li-ion pack typically means the cells won't recover.