>>78859
>while i don't have a self-built solar system yet
Why do you need a "self-built" small solar battery charger when you can easily get one for around $85 to $100 today?
>the next laptop i am building will only use the same tool batteries that i use to power my drill and my angle-grinder
Cool, but you better stock up on spare backup batteries then. I've gone through tons of those kinds of power tool batteries over the years, even De-Walt which is higher end product. Many companies obsolete battery tech and you have to buy new ones with adapters for older tools and the voltages can vary between new and old. Basically the market is designed for planned obsolescence today. That is why I would recommend 12V batteries and an inverter because those always stay the same and as long as there are cars and trucks there will be 12V batteries.