7.2V Pellenc AP25 Tying Machine Replacement Battery 3000mAh

My Pellenc tying machine is skipping ties and the tension feels weak halfway through the row — is the battery dying or is something else wrong?

Weak tension and missed ties mid-row are classic signs of voltage sag under load — the motor is drawing more current than a degraded Ni-MH pack can deliver, and the cell voltage drops below what the tool needs to cycle properly. It's not always a dead battery; it can be a partially discharged one that reads fine on a charger but collapses the moment the tying mechanism engages. Run the pack down fully, then charge it in one uninterrupted cycle before testing again — Ni-MH cells recover better from a proper full discharge than from repeated top-ups. Check resting voltage after a full charge: a healthy 7.2V Ni-MH pack should read between 8.4V and 8.6V with a multimeter before you put it back in the tool.

My replacement AP25 battery charged fine but now the tying machine won't turn on at all after sitting in the shed over winter — did the battery fail?

Ni-MH batteries self-discharge significantly during long storage, and a pack left unused for several months can drop to a voltage so low that the charger refuses to recognize it or the tool's protection circuit blocks startup entirely. This is a known behavior with this chemistry — it's not necessarily a dead cell, it's a deeply discharged one. Put the pack on the charger and leave it for a full uninterrupted charge cycle even if no indicator light comes on immediately; some chargers need 10–20 minutes before they detect enough voltage to begin active charging. If the charger still shows no activity after 30 minutes, measure the pack voltage directly — anything below 5V on a 7.2V Ni-MH pack means it needs a recovery charge or has reached end of life.

The tying machine works fine for the first few vines then suddenly stops and starts again on its own — what's causing that?

Intermittent stopping and restarting under normal use on a Ni-MH pack is usually a poor contact between the battery terminals and the tool's battery bay, not a cell failure. Dirt, sap residue, and oxidation build up on the contact pads after fieldwork, and the resistance causes the tool to cut out under the brief current spike each tie cycle creates. Clean both the battery terminals and the tool's contact points with a dry cloth or fine abrasive, then check that the battery seats fully without any play. If the fault persists after cleaning, press the battery firmly into the bay and watch whether the cutouts happen at the same point in each tie cycle — consistent timing points to thermal cutoff from a weak cell, while random cutouts point back to a contact issue.