Batteries and Cold Temperatures
All Light & Motion batteries are tested at 55 degrees Fahrenheit. The advertised run times for every light are recorded and tested at this temperature. Deviations from this temperature do have an effect on the performance of the lights and this is an intrinsic quality of all Li-Ion batteries (every brand of light/battery).
Just like humans, batteries don’t like to be cold. Colder temperatures increase the internal resistance of the battery and diminish the capacity of the charge. This then results in shorter run times for that charge cycle. Using your light in cold temperatures will not have a lasting effect on the battery once it warms up but you will experience short run times during colder use.
We constantly are designing our products to shed heat efficiently which also means that when it is cold out the battery “feels” the temperature much more quickly (the same design that sheds heat also means the body of the light transfers the cold into the inside of the light.
Some ways to help prevent this from happening are to store your light in warm conditioned areas as opposed to leaving your light in a cold garage or outside, keeping your light in a jacket or pants pocket where the battery will stay warmer and to let the light “warm up” by turning it on for a couple of minutes prior to exposing it into the colder climates.
For more information on the chemistry of batteries and the effects of cold temperatures check out Battery University’s web article here