Copper

busbars

Copper is malleable and ductile, excellent thermal and electrical conductivities and good corrosion resistance.

Used in current collectors in cells and busbars in packs.

Copper Busbars

copper busbar current versus area

The red circles show data from 3 electric vehicle battery busbars. The current is an estimated continuous rating and plotted versus the cross-sectional area in mm2.

The gradient of the “straight line fit” shows that 6A/mm2 is a rough estimate for copper busbar size.

Copper Current Collectors

Lithium ion cell

The anode current collector in a lithium ion cell is copper.

Cu-OF

  • Oxygen Free
  • oxygen-free and non phosphorus-deoxidized copper
  • purity of 99.95%

Cu-OFE

  • Oxygen Free Electronic grade
  • oxygen-free and non phosphorus-deoxidized copper
  • guaranteed purity of 99.99%
  • minimum electrical conductivity of 101% IACS (International Annealed Copper Standard).
  • excellent hot and cold forming properties
  • easily weldable
  • good corrosion resistance
  • impervious to hydrogen embrittlement as it doesn’t contain oxygen
  • free of elements that evaporate in vacuum

downsides:

  • less easy to laser weld
  • not resistant to oxidizing acids, aqueous ammonia, hydrogen sulfide and sea water