The lamination technique is a simple and easy-to-apply technology, which simplifies the stacking process by reducing the number of components. The lamination process enables fast assembly speeds up to 100 m/min and therefore lowers the costs of the assembly process.
Subsequently, the materials are laminated by heat and pressure to obtain a mechanically stable connection. Lithium-ion batteries made from laminated and stacked sheets offer much greater safety than conventionally manufactured batteries as the separator of the laminated cells shrinks less during battery operation.
The fast charge and discharge capability of lithium-ion batteries is improved by applying a lamination step during cell assembly. Electrode sheets and separator are laminated into one stack which improves the electrochemical performance as well as the stack assembly process.
One method of achieving this to perform lamination of ultra-thin pouch form batteries to a flexible substrate using a lamination film. However, the lamination process requires the pouch cell battery to be subjected to severe conditions such as pressure and temperature although for a short amount of time.
After lamination, the batteries have been subjected to U-flex-to-install (static folding) and dynamic U-folding tests along with accelerated life testing. Finally, the state of health (SOH) degradation rate of laminated batteries has been compared to that of unlaminated ones which were subjected to the same tests.
A significant reduction in the capacity fading at high C-rates is observed upon lamination. Additional compression is applied on the cells to compare the effect of lamination and compression on the cell performance. The laminated cells show an improvement in the fast charging capability in comparison to the non-laminated cells. 1. Introduction