Untimely Battery Death: How to Avoid It.

As a night photographer I’m a proponent of the philosophy of “carry a big battery” and you’ll never miss that shot.  However I learned a hard lesson about my corral of batteries that I feel I must pass on before you too shriek in terror when you find your once reliable battery has met an untimely (and inconveniently timed) demise.

Lithium Batteries are Greatly Disturbed By Heat

This was the lesson I learned the hard way. I had a stable of five fully charged batteries ranging in size from 1800 milliamp hours all the way up to 8,000 milliamp hours. I kept them in a shaded part of my car through some summer days in the San Francisco Bay area.  And that was how I learned that Lithium + Fully Charged + Heat = premature death.  The two low capacity batteries previously allowed me two and a half hours worth of continuous night exposure. Now they each last about 12 and 15 minutes.  The three HUGE batteries that could easily power my camera all night long for continuous exposures now have about the same life in them as my regular 2000 mA hr batteries – that is, about 1/3 as long as they used to last.

I learned why my brutish batteries became so feeble at Battery University.  In a nutshell I discovered that storing batteries cool (less the 86 F) and at 40% charge is the most effective at prolonging their life.  What I do now is keep all of my batteries in a separate pouch which I take with me into my office or home – even if I leave my camera equipment in the car.

I’d like to heed the 40% storage method – but not all of my chargers accurately tell the battery capacity. And worse, when I’m running out for a night of exposures, I usually don’t have an extra hour or two to fully charge my workhorses.

And yes, repeated discharge and recharge of those batteries will diminish their life, but NOT as fast as fully loaded batteries baking at a mild 90 degrees or more.


9 thoughts on “Untimely Battery Death: How to Avoid It.

  1. Enrico

    This also applies to some lead-acid batteries. I found places in my car to store even fully charged batteries without getting warm from the summer heat. I put them in the corners of the trunk and cover it with a blanked, pants or something similar. That way I can even keep water in the trunk when the car is baking and it won’t get warmer than normal room temperature.
    Check your car next time it stood in the sun which areas are not warm…

    1. Steven Christenson

      Lead acid batteries are more tolerant of heat and cold, but lead acid batteries don’t like being used in the heat – shortens their life. Cold robs lead acid batteries of capacity – but that is only a temporary problem. Lithium batteries are robbed even more by cold.

      For safety reasons, I don’t recommend putting anything over a lead acid or any other battery unless it’s in an enclosed container. If a blanket or clothing gets wet it could conduct enough current to start a fire (that’s something for Mythbusters to try!). Using something like a power tank or jump start system should be fine.

      To understand how things can go awry with batteries, drop a 9 volt battery and some coins in your front pocket. NO DON’T DO THAT, I’ve already done it for you. Trust me it’s NOT pleasant.

      1. Enrico

        Good tip with pants etc. could get wet and short the battery. Although it is not very likely to get wet in a car except there is a hole somewhere where the rain could get in.
        The battery contacts should be cover with something non conducting anyway like plastic or put tape on it because stuff can move around in the car during driving and then maybe shortened by something else in the car.

        I know that shorten a battery is a big hazzard and will start a fire!

  2. Stuart Nafey

    Thanks for the link. I wonder if an insulated cooler would help. It sounds like you use a separate carrying case for your batteries anyway. One small ice pack in the morning might help keep it at that Goldilocks temperature all day.

    Good stuff. Thanks.

  3. Robert Milton

    Thanks for the tips and great stories! – the ice chest idea is excellent. I’ve been more concerned about how heat would affect my dSLR and lenses – had to leave my gear in the back of a van for about 5 days parked at a trailhead, so pulled the CF card, battery, and tried to find the coolest possible place for the camera bag.


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