@rafe: I have a set of those electrical tools, right next to the gas powered ones I had to buy to replace them.
They do NOT work except for the smallest lots and smallest jobs. There just isn’t enough power in lightweight electric motors and batteries for the job and if you make one, they would weigh a lot. Husqvarna sells a backpack lithium battery which lasts ~2 hours, that is on top of whatever replaces the backpack motor that current 4-stroke gas engines occupy.
Tesla cars for example have a battery pack that weighs 1200 lbs on itself and requires 4 motors weighing ~400 lbs total and they get a dismal 200-300 mile range and refuels in 4-8 hours.
The average gas engine in a similar sized car weighs ~350 lbs and the gas tank, filled, weighs ~50lbs and roughly 1.5-2x the mileage of a Tesla and refuels in less than 10 minutes.
So you can easily see that a small engine replacement would weigh 4x as much. Given a commercial weed whacker weighs as much as 50 lbs, the battery + motor would weigh 200 lbs, and you need to haul about twice as much batteries as well just to make sure you make it through the day.
Its easy to conclude that since your small apartment yard can be mowed with an electric mower, everything should be electric, but to do that with the commercial versions that do football fields are utterly impractical. Those riding mowers and snowblowers are basically small cars, Tesla , VW etc barely can get their driving cars at a reasonable price point and can’t maintain production to replace gas cars.
Obviously you would have to charge the batteries as well while on a job, so you would have to run a gas engine generator anyway except you compound to the inefficiency because gas generator > electric is about 40% efficient and then electric > motion is about 70% efficient making the whole system about 30% efficient. While gas > motion is about 50-70% efficient, so now you just doubled your gas consumption.