How long to charge battery with solar?

boiseites
boiseites Member Posts: 23
edited May 2021 in Battery/Electrical & Solar
We have a 2021 320S, for which we have purchased the https://smile.amazon.com/Renogy-RNG-KIT-STCS100D-SP-Monocrystalline-Controller-100W-Waterproof/dp/B01NADR1CI/ref=sr_1_1?dchild=1&keywords=Renogy+100+Watt+Eclipse+Monocrystalline+Charge+20A+Voyager+Waterproof+Controller+Solar+Suitcase,+100W-Waterproof&qid=1620271185&s=lawn-garden&sr=1-1 
We just hooked it up (no problems!) and are awaiting it to fully charge our new Renogy 12V 100AH AGM battery. About how long should it take? Full sun today.
· Share on FacebookShare on Twitter Share on Google+

Comments

  • Dutch061
    Dutch061 Member Posts: 765
    edited May 2021
    Loaded question, max solar charge rate will be around 8 amps (100/12=8.33). So it depends on the state of charge in the battery when you begin.

    Brad
    2020 400 BDL aka "Boonie"
    2022 Black Series HQ19 aka "Cricket"
    2021 F-250 Tremor with PSD aka "Big Blue"
    Concord, NC 
    · Share on FacebookShare on Twitter Share on Google+
  • boiseites
    boiseites Member Posts: 23
    Well, it is a brand new Renogy battery.  So, minimal charge???
    · Share on FacebookShare on Twitter Share on Google+
  • Dutch061
    Dutch061 Member Posts: 765
    It will still depend on the depth of discharge. The age of the battery (older has higher internal resistance) will take longer to charge or may not fully charge. 

    Example, if in 24 hours you use 24 Amp Hours it will take at least 3 hours to fully recharge in full sun. You can replace the energy used (measured in Amp Hours) at the rate of approximately 8 per hour. 

    The only way to reduce the charge time is being able to charge at a higher rate or use less energy. 

    Brad
    2020 400 BDL aka "Boonie"
    2022 Black Series HQ19 aka "Cricket"
    2021 F-250 Tremor with PSD aka "Big Blue"
    Concord, NC 
    · Share on FacebookShare on Twitter Share on Google+
  • pthomas745
    pthomas745 Administrator, Moderator Posts: 4,530
    What are you using to monitor your battery?  What readings are you getting?  Are you measuring a "rested battery?"

    2017 Outback
    Towed by 2014 Touareg TDi
    · Share on FacebookShare on Twitter Share on Google+
  • Sharon_is_SAM
    Sharon_is_SAM Member Posts: 10,061
    Be aware that it can take a new battery multiple cycles before it assumes it’s full capacity.  Check out your battery specs.
    Sharon / 2017 T@B CSS / 2015 Toyota Sienna Minivan / Westlake, Ohio
    · Share on FacebookShare on Twitter Share on Google+

Categories