Many users may not know the consumer-grade Li-ion batteries can't be charged below 0°C (32°F). When attempting to charge them in below freezing temperature, most of the lithium ions fail to intercalate into the graphite anode. Instead, they plate the anode with metallic lithium. So charging will electroplate the anode with lithium rather than recharging it. And it's a chemical reaction referred to as "Lithium Plating". When it occurs, the internal resistance of the Li-ion battery increases and reduces the rate of chemical metabolism. It will cause a permanent reduction of the battery's capacity, and continue to reduce its capacity each time this reaction occurs.
And it's also dangerous. This lithium plating of the anode isn't nice and smooth. It may form in dendrites, little sharp tendrils of lithium metal growing on the anode. These dendrites can put unexpected pressure on the separating membrane, which may cause a short circuit or dead battery.
Li-ion can be fast charged from 5°C to 45°C (41 to 113°F). Below 5°C, the charge current should be reduced. And no charging is permitted at freezing temperatures because of the reduced diffusion rates on the anode. Besides, though the permissible discharge temperature for common Li-ion batteries is -20°C - 60°C (-4°F to 140°F). If your batteries aren't up for the task, such as shooting in extremely cold winter, ice diving, etc. it's suggested to use batteries which can withstand low temperature in your cameras and dive lights.
And it's also dangerous. This lithium plating of the anode isn't nice and smooth. It may form in dendrites, little sharp tendrils of lithium metal growing on the anode. These dendrites can put unexpected pressure on the separating membrane, which may cause a short circuit or dead battery.
Li-ion can be fast charged from 5°C to 45°C (41 to 113°F). Below 5°C, the charge current should be reduced. And no charging is permitted at freezing temperatures because of the reduced diffusion rates on the anode. Besides, though the permissible discharge temperature for common Li-ion batteries is -20°C - 60°C (-4°F to 140°F). If your batteries aren't up for the task, such as shooting in extremely cold winter, ice diving, etc. it's suggested to use batteries which can withstand low temperature in your cameras and dive lights.