The next upgrade for our Solar Power System was a Really Big Lithium Ion Battery (RBB). When we first installed the system in 2020, I didn’t have a cost-effective solution for Lithium Ion (LiFePo4 chemistry). That came later with the acquisition of a lot of LiFePo4 cells. Since then, I’ve built two small batteries to get used to the technology; one as a portable solar generator, and a slightly larger one to power the ham shack. With those under my belt, it’s time to tackle a 48-volt battery to replace the existing lead acid batteries.