I've had a LiFePO4 with no BMS in the Prius for 5 years now. They don't do well getting deeply discharged, and can't be charged while below freezing, so it's important they live inside the cabin if it freezes where you are.
I've got a small 4Ah pack in the glovebox of my Acura at the moment. Decided to add a balancer to that one, which I recommend.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1