Canon tip: Battery charging in cold conditions

When charging the battery from your EOS DSLR, you can usually count on it being fully charged from empty within two hours.
However, in cold conditions, you should ensure you give yourself more time. This is because when charging at temperatures below 10 degrees Centigrade (50 degrees Fahrenheit) it takes almost twice as long. At low temperatures, the charging speed is reduced to help protect the batteries; so if you are working in cold environments, try and keep the area around the battery charger as warm as possible if you need to charge them efficiently.