Electric cars contain batteries that are highly temperature sensitive. Sometimes they have to be cooled and in hot climates they need to be warmed up. The autonomy and life span of the batteries is highly dependent on the temperature. However, the range of electric vehicles also depends on the weight of the car. By keeping the batteries at a much more efficient temperature, we can save kilos per vehicle!
In these vehicles is also a lot of (power) electronics, which generates a lot of heat and needs to be cooled efficiently without using heavy cooling elements or heavy fans or pumps.
Also think of the charging stations for the electric vehicles where a lot of energy has to be transported to the vehicle in a short time. The power electronics enable the electrical conversion, generates a lot of heat that must be efficiently removed.
But not only electronics components are a thermal challenge. Mechanical parts such as shock absorbers, motor cooling and brake discs must also remain within certain temperature ranges to remain performing.