A Battery Management System (BMS) is a system that monitors and manages a lithium-ion battery pack. It ensures the safe and efficient operation of the battery by balancing its cells, managing charging and discharging processes, and protecting the battery from potential hazards. Not all lithium batteries come with a BMS. Specifically, like the 18650 cylindrical cells or lithium iron phosphate (LiFePO4) prismatic cells that often use in engineering projects, these raw cells are pure chemical containers when they leave the factory without any protection circuit inside. The BMS provides overcurrent protection, which helps prevent fire risks. Think of the BMS as a computerized gatekeeper, making sure your. Lithium-ion batteries have revolutionized modern technology, powering everything from smartphones and electric vehicles to large-scale energy storage systems.