All you have to do is look at the source required to keep all of these batteries charged. I would like to be convinced, I really would, but, I’m not. Energy is not free, it has to come from somewhere. How many batteries and how many chargers do you have scattered around your garage Russ. Batteries, chargers and electric cords now grow like weeds taking over entire work benches and requiring their own dedicated charging tables. Then there is the what do you do with them when they’re wasted. Some last quite a long time, some less than a year. Disposal of lithium batteries and accessories is now an industry. There is no panacea, only trade offs.