7.2V Homelite UT44171 Hedge Trimmer Replacement Battery 1800mAh

My Homelite shrubber cuts fine for a few seconds then the blades slow down and almost stop — is that the battery dying?

That blade-bog pattern on a 7.2V Ni-MH tool usually means voltage sag under load, not total capacity loss — the pack can't sustain current draw once the blades hit resistance from thicker stems. Check resting voltage with a multimeter after a full charge: a healthy pack should read at or above 8.5V at rest, and if it drops below 7V the moment blades engage, the cells are worn. Let the battery cool completely between charges — Ni-MH packs in light garden tools are often charged warm, which accelerates this exact degradation. Try the voltage-under-load test first before assuming the new battery is at fault.

I charged this Homelite shrubber overnight and the blades are still weak right out of the charger — why?

Ni-MH batteries shipped or stored for months arrive partially discharged, and a single overnight charge on a low-rate charger may not fully recover them — this is especially common with 7.2V packs in small garden tools that sit in warehouses between seasons. Run two or three full discharge-and-recharge cycles before judging performance: use the trimmer until the blades noticeably slow, then charge completely. We've seen freshly installed Ni-MH cells in this voltage class perform 20–30% below their rated capacity until cycled. After the third cycle, if blade strength hasn't improved, measure pack voltage immediately after charging — it should be above 8.4V.

The Homelite UT44171 worked great last fall and now it won't hold a charge after sitting in the garage all winter — did it just self-discharge completely?

Ni-MH cells self-discharge faster than almost any other chemistry — a 7.2V pack left uncharged through a cold winter can drop low enough that a standard charger won't recognize it as a valid battery and will refuse to charge it at all. This is called a deeply discharged state, and it's the most common reason a stored shrubber appears completely dead in spring. Try applying a slow trickle charge for two to four hours using a compatible charger that has a recovery or conditioning mode, which can bring the pack voltage up enough for the charger to resume normal charging. If the pack voltage reads below 5V after that trickle period, the cells haven't recovered and a replacement pack is the correct next step.