Because I like the cold and spend a lot of my time in the world's most extreme environments, I get asked a wide variety of questions. And while everyone from kindergarteners to CEOs wants me to discuss the finer points of my taking morning constitutional at 40 below, one separate question consistently pops up:
How do you keep batteries from dying in the cold?
First, it's important to understand why exactly batteries 'die' in the cold. Batteries create a current when connection is made between the two terminals (positive and negative). This triggers a chemical reaction inside the battery. When it's colder the reaction occurs more slowly. When it's warmer the reaction happens faster. Ultimately, the faster the reaction, the more electrons (current) that are produced and the more charge the battery has. Not surprisingly, most batteries do best at room temperature or a little warmer.
Next, realize that my cold and your cold may be two very different things. Now don't get me wrong, I'm not trying to belittle your idea of cold and freezing, but different ranges of cold temperatures have a more adverse affect on your battery's ability to hold a charge and I use different strategies to stay powered up depending on the temperature.
Regardless, here are few simple guidelines to give your battery the long life it deserves no matter the conditions.
Keep it warm -
I employ a lot of different strategies to keep my batteries warm. From sticking my Goal Zero Sherpa 50 power pack inside my sleeping bag at night to keeping spare Guide 10 rechargeable AA's in my pocket during the day while I travel, anything that you can do to keep your batteries from freezing will increase their ability to generate charge. If you're really concerned you can also fill a sturdy water bottle with boiling water and place next to the battery.
A little goes a long way_
- while it may be really really cold, certain places can be warmer than others. For example, I keep my Sherpa 50 in deep inside my backpack wrapped in a spare jacket while my Nomad panel is outside more exposed to the elements. Solar radiation absorbed by my pack keeps the Sherpa a bit warmer. I also employ this strategy in Antarctica - I run the cord from the panel through a small hole I cut in my tent. Inside the tent, it's relatively toasty and I'm able to recharge all my expedition electronics with relative ease.
Minimize screen time
- I do a lot of cold weather photography and videography. Video/camera LCD screens suck a lot of juice. If your camera has one, use a view finder. Additionally make sure to turn off your Sherpa 50 immediately after you are finished using it.
I'm not dead yet
- often times your device will show your battery is dead when in fact it's not. It's just cold. I can often get three or four uses of batteries that show no charge simply by warming them up. Additionally, make sure to warm your device before you use it as well.
_- Let's face it we all can't MacGyver our way out of a bad situation, and while I've tried many times, I still can't charge my cell phone with a stick of chewing gum and a paper clip. If it's a longer trip where power is really important bring an extra set of Goal Zero 'rechargeables' and a Guide 10. It's one of most versatile charging systems I've ever used! If that doesn't work, get Chuck Norris to karate chop it!
- one of the great things about Goal Zero power packs and batteries is that you can charge them in a variety of ways. Before hitting the trail, I make sure each one is fully charged.