Battery chemistry for a hot environment

Discussion in 'General Electronics Chat' started by MrSoftware, Dec 2, 2013.

  1. MrSoftware

    Thread Starter Active Member

    Oct 29, 2013
    I need some help with a battery chemistry choice. My project requires that my battery be in an enclosed box that will be out doors during the summer months of areas like S. Florida and Arizona. I will try to shade the battery box from direct sun light, but I'm sure the temps will still reach several degrees over 100F. It needs to be 12V, approximately 9Ah capacity and it must have a low self-discharge rate. Lead-acid will probably operate OK, but its self discharge rate is too high; we want to go at least several months between recharges. Lithium Ion or LiFe looks good as far as self discharge, but I'm concerned about the temperature. Can anyone suggest a battery chemistry that would be best? Rechargeable is preferred, but disposable is OK if the cost is relatively low.
  2. GopherT

    AAC Fanatic!

    Nov 23, 2012
    Make shade for the lead acid battery with a small solar panel. That should take care of your self discharge rate.

    See AGM battery. 80% of charge capacity after 6 months and 140 degreeF operating range.
  3. ronv

    AAC Fanatic!

    Nov 12, 2008
    Take a look at the old fashion lantern battery. Not rechargeable but...
  4. bountyhunter

    Well-Known Member

    Sep 7, 2009
    Batteries REALLY do not like temps above about 80F. They function best between about 60 - 80F. That's why auto designers put the little heat covers on batteries under the hood.
  5. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    Tadiran has batteries rated to 125deg C op temps.. (TLH series) and many other "high performance" batteries.
  6. GopherT

    AAC Fanatic!

    Nov 23, 2012
    Those are great batteries but best used for back-up or low load applications (5 mA and less). Which raises a question for the OP if he ever returns. What type of load (duration and interval) do you expect to supply? Constant low power or high power for short bursts each day, ...

    The Tadiran batteries can handle high temperatures but don't put them anywhere that physical damage could cause them to open up. They are filled with lithium metal and thionyl chloride (SO2Cl2), nasty stuff.