An electric vehicle battery comprises three primary components: cells, modules, and packs. Cells are the basic units that store energy, typically lithium-ion based, containing an anode, cathode, and electrolyte. Modules consist of multiple cells connected in series or parallel, enhancing voltage and capacity. Packs integrate several modules, forming the main energy storage unit. Battery Management System (BMS) ensures safe operation by monitoring cell voltage, temperature, and state of charge. Collectively, these components enable efficient energy storage, conversion, and delivery, powering electric vehicles with reduced emissions and increased sustainability.