Looking to go green re lawnmower.

Be on the lookout for Lithium Iron Phosphate LiFePO equipment, there's some riding mowers that use them for sale now. Much less likely to burn down your house, regular lithium ion turn into a big fireball if they get over 175F but the iron phosphate has to get all the way over 500F before they go into thermal runaway. More stable.

Haven't seen any string trimmers yet though, that's what I'm really looking for.