Battery Pack
A battery pack is the complete traction-battery unit installed in an EV, built from connected cells or modules to meet the vehicle's voltage, energy, and power requirements. It is not a single cell or module. EUR-Lex: Regulation (EU) 2023/1542 on batteries and waste batteries
What belongs to the pack
Cells are always central, while the rest of the design varies. A pack may use module enclosures or connect cells more directly. Depending on the architecture, pack-level mass and volume can include busbars, contactors, fuses, sensors, battery-management electronics, cooling hardware, structural frames, seals, and a protective casing. Some thermal-management equipment may sit outside the enclosure, so no single component list defines every EV pack. Argonne National Laboratory: A Manual for BatPaC v5.0
The pack is the level at which vehicle makers usually quote total battery voltage, gross or rated energy, mass, and installation. Its internal layout affects packaging, cooling, crash protection, service procedures, and pack-level energy density. Neither the presence of modules nor a cell-to-pack layout determines those outcomes alone.
For the deeper electrical configuration, construction, and trade-offs, see Battery Pack & Configuration.