Every description of hybrid electric vehicles goes to lengths explaining how good it is that an electric motor can be used in cases where the internal combustion engine is not very efficient and thus save fuel and lower the environmental impact.
Now what happens if it's −25 Celsius (appr. −13 Fahrenheit) outside? Such temperatures are not that uncommon - there're cities with population over 10 million in areas where such temperatures persist for months. AFAIK batteries discharge waaaay faster at such temperatures.
Will the battery in a hybrid electric vehicle still perform well in severe frost or will the vehicle just run as plain old internal combustion engine vehicle?