If you are allowing the pack to get above 60C (Which is very hot... burn you quick hot...) there will be other things to worry about.
so -
* Regular Use
* Failure mode
...
Failure mode is ... eh... an ugly subject. We are all still learning what to do when things go sideways. Just make sure that the low melt temp materials are not used for any insulating. Do your insulating with rigid, high temp, low-leakage materials. The case it all resides in - can be duct tape - IF - you are not depending on it for
heat sinking
As for Regular use
Dont leave it in the back window of your car in summer in the desert
Dont drive the cells so far past their continuous C rating that you make that much heat
I have never, in my career, driven a lithium pack (as measured external) anywhere near 60C - and -
had much more fun with the pack.
Know what I mean?
That said, there are a lot of products on the market which push cells to the absolute limit. They all end up needing heat sinking or active cooling. For a small ebike pack - I have always utilized air cooling and good sense - for good results.
Let us know what you find
-methods