UPS can take the battery if the battery is under 300 WH. That is their written rule. You just have to inform the rep, and ship via ground. fill out a couple forms no big deal.
You can call the hazmat dept. and they will have to take it.
@lilracerboi Your obviously only shipping within State of US. How about shipping from one country to another.
I just sent a spaceell via ground service in Aus no issue, but suspect it eould be an issue if by air… Was going to try by sea but that would take ages.