Gardena Accu75 4.8V Grass Edge Trimmer Replacement Battery

My Gardena 8802 edge trimmer cuts for a bit then slows down and feels like it's losing power mid-session — is that the battery dying or something else?

On low-voltage NiMH packs like this 4.8V system, voltage sag under load is the most common cause of mid-use slowdown — the blades create enough draw to drag a degraded pack below the tool's minimum operating threshold, and the motor bogs before the battery is technically empty. The original Accu 75 packs are old enough now that most have lost significant capacity through repeated shallow cycles and standing in partial discharge over winter storage. Fully charge the replacement, run the trimmer until it slows noticeably, then immediately measure the pack voltage across the terminals — a healthy 4.8V NiMH should still read above 4.4V under that condition. If it's reading 3.8V or lower, the cells were already degraded before the load hit them.

New battery charged overnight but the Gardena trimmer blades barely move when I switch it on — what's wrong?

This usually means the NiMH cells shipped in a deeply discharged state and the charger topped out too early without fully recovering them — a known behaviour with older Gardena charging units that lack a proper reconditioning cycle. The cells aren't dead; they need a slow recovery charge or a charge-discharge-charge cycle to break through the voltage depression. Put the battery on charge for a full cycle, let it rest for an hour, then try the trimmer again before assuming the battery is faulty. If the blades still barely turn, check that the battery contact pins on the trimmer body are clean and making firm contact — corrosion on those pins is a common cause of high resistance at this voltage level.

I stored the Gardena 8802 in the shed over winter with the battery in it and now the charger won't do anything with it — is it dead?

NiMH cells left in a discharged state for months can drop so low that standard chargers refuse to recognise them as a valid pack — this is called a sleep or zero-volt condition, and it's common with seasonal gardening tools stored without a top-up charge. The cells are often recoverable, but the Gardena charger won't attempt it at that voltage. We've seen packs in this state recover after a brief trickle charge applied directly at a very low current (around 100mA) for 30–60 minutes to bring cell voltage back into the range the charger will accept. If you don't have the means to do that, fit the new replacement pack, then make a habit of charging it to full before the next winter storage — that single step prevents this entirely.