I bought an Earthwise 24-volt lawn mower last year to keep my lawn in check. It worked pretty good, but the battery didn't last the summer. It just stopped charging. I of course got lazy and didn't contact Earthwise to get a replacement. When I pulled it out of the garage this year and noticed that I couldn't mow longer than ten minutes I remembered... Oh yeah, I was going to call them about this...
Well, the one year warranty expired so that left me with one choice... buy a new battery. I decided to look online for replacements and found one at Home Depot for almost $150!
$150 is a little more than I was willing to spend, so I started looking around and I found a blog post talking about how the internal components of the battery are just two basic universal batteries!
It turns out the post was right. You can open up the battery housing by unscrewing the screws around the under ledge of the housing.
When you pull off the top you have two super cheap generic 20 Ah Chinese batteries.
So there you go, pay Home Depot $150, or hack your battery yourself and only pay $80. What would you choose?