Red Eye, good to know the heating pad worked. Did you happen to monitor the temps and see how warm they got, with the pad on?
FWIW, I emailed LiTime about using aftermarket heating pads or blankets (was eyeing up their new 165ah Group 31), and they told me that they did not recommend using any, because they’re not as reliable and don’t heat as thoroughly as internal heaters. While that may be true, I did get the vibe that it was also a liability thing, them not wanting to risk telling me it was okay to use one, and then having to worry about warranty coverage later on if something went wrong, which I get. While researching aftermarket heaters, I did find one that is built by a company that sells the batteries themselves as well, so there’s at least one battery company out there that doesn’t have a problem with external heating pads. I can’t remember the company, but their heater was basically a blanket like you see on batteries in diesel trucks, with a pad on the bottom, and a temp sensor and timer built in, powered off the battery itself.