That battery is a great addition. i already have a different brand electric cooler and have been using it in my garage as the fridge there. I use a jackery 240 to power it when traveling with it but would have gladly bought the battery if i had know of it.
any risks of the LiIo battery in such a hot car? I've been weary of them ever seeing one catch on fire on Jasonoid channel when he was looking at a battery powered cooler. I suppose to minimize the risk one could forgo the battery pack and use a LiFePo4 battery bank to power the fridge instead?