I read an article that made the case that lithium of batteries are sensitive to the direction of the heat gradient. Tried looking, can't find it. But the upshot was you want the gradient parallel to the electrode layers not perpendicular. Which means you want to remove the heat from the ends of the cell.
Money quote: For automotive applications where 80% capacity is considered end-of-life, using tab cooling rather than surface cooling would therefore be equivalent to extending the lifetime of a pack by 3 times, or reducing the lifetime cost by 66%.
Meaning battery packs that last not 150,000 miles, but 450,000 miles.
