Pair agree on Hyundai's propsoal of Z-stacking
Hyundai Motor and LG Energy Solution were in disagreement over which method of battery production to use at their electric vehicle (EV) battery joint venture in Indonesia before eventually reaching an agreement, TheElec has learned.
The South Korean automaker wanted to use Z-stacking for battery cell assembly at HLI Green Power, while the battery maker has argued that they should continue to use lamination and stacking as they did before.
These methods refer to how battery materials __ cathode, anode and separator __ are stacked during battery production.
Hyundai Motor ultimately won the argument and the pair had agreed to use Z-stacking for battery production in Indonesia.
LG Energy Solution had been using lamination and stacking, its own proprietary method, for batteries it supplies to Hyundai Motor before. It attaches the separator between the anode and cathode before stacking the resultant bi cells.
Z-stacking is used by its rival SK On and Samsung SDI. It stacks anode, cathode and separator alternatively.
People familiar with the matter said lamination and stacking have an advantage in productivity, while z-stacking is more stable.
The dispute between Hyundai Motor and LG Energy Solution was likely caused by the recall of Kona EVs last year, they said.
The pair failed to pinpoint an exact cause at the time and this likely led to the automaker preferring stability over productivity for the batteries it uses, they added.
While LG Energy Solution had a 99% yield rate for its lamination and stacking method, as it hasn’t done many Z-stacking, its yield rate for this method was around 85%, a different group of people familiar with the matter said.
Meanwhile, HLI Green Power is planned by Hyundai Motor and LG Energy Solution to initially have a production capacity of 10GWh per year and will start production in 2024.