Running discussion on SP, page-62068

Yep, both charging and discharge (i.e. use) of lithium batteries are much less efficient in very cold weather - Teslas have a snowflake icon that lights up to show that range may be affected in extreme cold. But it's generally not catastrophic, on average about a 20% reduction in range once you hit subzero temps. There are ways of getting around it such as thermal management systems that generate heat around the battery, but they also take energy from the battery. No doubt this will gradually improve as the tech develops