How electric car batteries are made
Electric cars of 2023 carried anywhere from 21 to 123 kWh of battery, and the average model had 80.
- stations
- 6
- things upstream
- 83
- raw sources
- 28
- steps from the ground
- 9
The short version
An electric car battery pack is built from hundreds of lithium-ion cells. Cells are grouped into modules, or sometimes placed straight into the pack, then welded to metal busbars, cooled by aluminum plates and watched by electronics that track every cell. A sealed steel or aluminum housing is bolted under the car.
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Sort matched cells
Cells from one batch still differ slightly, so each is tested for voltage, capacity and internal resistance. Only closely matched cells go on together, and every later stage inherits what this one leaves behind.
Goes in -
Stack and compress modules
End plates squeeze the stack with a controlled force, leaving room for the swelling cells do over a charge cycle. A camera checks terminal alignment. Newer cell-to-pack designs skip modules and go straight into the pack structure.
Goes in -
Weld the busbars
Laser, ultrasonic or resistance welding joins cells into an electrically connected string. Technicians pull-test the joints, because one that looks fine can still carry too much resistance.
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Fit cooling and electronics
Liquid cooling plates go between the cells, along with high-voltage contactors, fuses and the management system that watches every cell's voltage and temperature.
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Seal the housing
Crash structures and seals against water and dust close up the enclosure, a case something like a sealed steel suitcase.
Goes in -
Test the finished pack
Finished packs face leak and insulation tests, charge and discharge validation, vibration rigs and thermal cycling before being bolted under a car.
Worth repeating
- Three cell types dominate electric vehicles: cylindrical, prismatic pouch and prismatic can.
- Traction batteries hold far more energy than the starting batteries of combustion cars.
Back to the ground
Follow every input upstream and electric car battery starts as these 28 raw sources.
Everything it is made of See it on the map
Open the whole family tree
Where it goes next
Electric car battery feeds 1 line directly.
Keep walking
Sources
- MeraEV: How an EV battery is made
- Sunlith Energy: Battery pack assembly process
- Electric vehicle battery
- Lithium-ion battery
Cite this page: "How electric car batteries are made." Assembly Line, 2026-11-03. https://assemblyline.org/make/ev-battery