I want to make a solar charger for tool batteries. I’m thinking plug a standard AC dual 5 amp 20v battery charger into an inverter charged via a solar battery bank. Enough to charge four batteries during the day. That’s not in the budget so I’m going to start small with just one battery at a time (600watts?). Maybe two batteries a day if I can afford it.

Who here has built such a battery bank? What advice do you have? What handy online calculators do you recommend? Is there a spreadsheet available that is better than a calculator? In the past I would have looked for those myself but search engines are totally useless now. Would you rather have one big battery hooked up to the inverter or a bank of smaller batteries in series or parallel?

  • mortalic@lemmy.world
    link
    fedilink
    arrow-up
    1
    ·
    2 months ago

    Sounds like you’re well on your way. Mine still has some issues so I’d love to stay in the loop on your build a d will offer any help I can.

    That’s a good point about the multiple batteries, I guess I hadn’t considered that.

    I was able to get mine to run a chest freezer over the summer, but once the sun shifts to fall it isn’t able to charge back up fast enough. I’ve only got two panels and they are on the wrong side of the roof. Also we had a power outage last year during a snowstorm. I was able to plug my house fridge/freezer into my system and it kept our food from going bad. Running a few cpaps should be simple.

    There are a lot of uses for a small offgrid solar battery system