Here's what I did about my chainsaw needs.
The top Echo is about 35 years old, bought it when we moved up here and need a saw to feed my new fireplace. Cut a lot of wood, but only needed it about a week every year, then it sat. After a few years it sat for years at a time because I didn't need that much wood anymore. It would still start, usually on the second pull, but was never sure if I would store it with or without gas. Finally after sitting for over 10 years without use I had the carb. cleaned and rebuilt, then I sort of retired it.
I still needed a chainsaw for tree trimming around the house, as did the boys and their houses, so I went out and bought an Echo battery.
This thing is every bit the chainsaw as the old one, about the same weight, same speed and starts with just the pull of the trigger. It's said to be good for 100 cuts before a recharge, (that's a lot of cuts), if you had two batteries it would be a days worth of work. It does not slow down as the battery get weak, same speed then bam ! it's done, fairly quick recharge.
Now I don't have to worry about bad gas, (don't go there) battery keeps a good charge (I've had it a year and still indicates full power)
So it's a win/win for me and the small amount of time I need a chain saw. Nice option is the same battery will fit a number of items, from weedwips, to blowers, to even a lawn mover.
https://i.imgur.com/LOfJk6P.jpg