Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

How to calculate how fast it would take to charge/discharge a battery

  1. Sep 3, 2011 #1
    I was wondering if it was possible to use, simultaneously, a 30 amp (or higher) charger on a car battery and a DC to AC (say, 700 watts) power inverter.

    Where I live we have 8 to 10 hours of power outages in 2 hour intervals during the day. Instead of wasting money on expensive office UPSes, I was wondering if I could make something a bit more sturdy using cheaper car batteries.

    What I wanted to know is, how fast would a 30 amp charger take to charge a car battery? And how long could a car battery deliver 700 watts? I'm a complete n00b here so if someone could point out the specific formula/equation to use to calculate this, I would greatly appreciate it!

    Ideally I would like enough batteries (I could just hook up a bunch of them up in parallel?) to deliver 700 watts for 4 hours, that would then recharge within 2 hours (when the power's back on).

    Lastly, does anyone have tips for actually setting up this kind of apparatus? Specific parts/companies?
     
  2. jcsd
  3. Sep 3, 2011 #2
    It looks like what you really want to build is an inverter.
     
  4. Sep 3, 2011 #3

    phinds

    User Avatar
    Gold Member
    2016 Award

    I can't answer your question but I do caution you to exercise care in designing battery recharging devices because if you recharge too quickly (on some batteries at least) you may get a charge a few times but will quickly destroy the battery due to overheating then you will have lots of acid-filled door-stops on your hands (and that's assuming they don't explode --- I'm not positive they do that but it wouldn't surprise me)
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: How to calculate how fast it would take to charge/discharge a battery
Loading...