evan_stone•4d agoProlific Poster

My electric lawn mower battery died mid-cut last Saturday

I was about halfway through my yard last weekend when the mower just stopped. No sputter, no warning lights, just dead. It's a 40V battery I've had for about 2 years and I only use it for a 1/4 acre lot. I figured it was a bad cell since it was still warm but showed no charge on the meter. Turns out one of the terminals had corrosion from storing it in the garage over winter. I cleaned it with baking soda and water and it fired right back up, but I lost an hour of my Saturday trying to diagnose it. Made me wonder how many other folks with battery tools are tossing them for something simple like a dirty connection. Anyone else had a similar fix with their electric gear?

2 comments

2 Comments

umabailey4d ago

Did you consider that maybe the battery just wore out naturally? Two years of regular use for a 1/4 acre lot is a decent amount of cycles, and the corrosion might have been a side effect of normal wear. I had a similar 40V battery that stopped holding a charge around the same age, and cleaning the terminals only bought me another month before it really died. Sometimes you just have to buy a new one.

blake_smith4d ago

Wait, did you actually get another month out of it after cleaning? That's not really what I've seen in my experience. From everything I've read about lithium ion batteries, corrosion on the terminals doesn't usually mean the cells themselves are dying. It's more of a physical connection problem, not a chemical one inside the battery. I'd bet money that if you cleaned that terminal properly with baking soda and a wire brush, the battery would have worked fine for a lot longer than a month. Your mileage may vary of course, but I've brought back three different tool batteries that way and they all lasted another year at least.