tl;dr the battery cooling system of a Model S is like an engine from the current Golf, and the Leaf's like one from a 1960's Beetle.
The battery thermal management systems of the Model S and Leaf are complete opposites.
The Tesla circulates coolant through the pack. When it gets too hot, there is a chiller in the coolant loop. The system can also warm up the battery to optimal temperature for charging and operation when it is cold.
The Leaf battery is air cooled. Heat transfer to air is less efficient than to water, but it can suffice with the right system design. The Leaf cooling is passive. There is no fan; just convection moving air through the pack.
In a temperate climate, that could be enough to get the job done. In a hot location, like the American Southwest, it isn't. The first Leafs in that region were seeing capacity lose of up to 50% in the first year. Nissan had to replace the packs with a more heat tolerant chemistry. Even with the better battery, a 3 year old Leaf can have 15% capacity loss to a Tesla's >5%.
https://www.nimblefins.co.uk/study-r...-deterioration
https://www.nimblefins.co.uk/study-r...-deterioration
The first bar of the Leaf battery gauge is equal to 15%, and the rest 6.25%.
Battery Capacity Loss – Electric Vehicle Wiki
Linear Mode
