I wish I could install lithiums. Sometimes we have a day where it hit's -40... both C and F. This morning it's 8f/-13c, and it's going to be a lot colder in January and February.
Any ideas? Simply relocating it to the hatch isn't going to be enough if the car sits in the cold for 16 hours.
And, FWIW, I'd probably use these:
https://www.ev-power.eu/LiFePO4-smal...e-CE.html#tab2
4 cells = 12.8v nominal, 14.6v peak, same as the cheaper battery you were looking at. 8 cells would = the more expensive one. You'd need to put bars between them but it's also easy to take the cells apart and re purpose them.