It’s possible to get a cordless mower.
I’m staying with friends right now, and as a favor, I’ve been mowing their lawn. They have a large front lawn and an even larger back yard. It’s a double lot. Plus, neither of my friends (a married couple) is really into yard work. At all. The front lawn got mowed only to keep the neighbors from complaining. The back yard was more like a meadow, with grass anywhere from calf to waist height. The mower they own is a rechargable Black and Decker.
It took me the better part of three weeks to get that damn grass mowed. I would kill the charge in less than an hour of mowing, so I had to take the lawn in chunks. Because the grass was so high and thick, there were times when I could only get about forty square feet mowed before the charge gave out.
So, while I wouldn’t recommend an electic mower for a large, overgrown lawn, it’s just fine for a small, well-kept lawn. Nice and quiet. Not self-propelled, but that just means you’ll get larger arm and leg muscles like I did.