We compared two suppliers. Both quote a “48V 100Ah LiFePO4 battery” — but one is 30% cheaper. Why?

Because “48V 100Ah” is a label, not a guarantee of what’s inside. The price gap usually comes from what you cannot see: the grade of the lithium cells, the quality of the Battery Management System (BMS), and the manufacturing process. A cheap battery often uses lower-grade cells and a basic BMS to hit a low price. The expensive one may use Grade-A cells from a top-tier brand and a smarter BMS. Same label, very different product. 48V 100Ah LiFePO4 battery