The demand for higher power and higher energy Li-ion and Li metal batteries continues to increase. In order to meet expectations the utilization of materials and cell designs need to be optimized. The result of the need for high utilization is that small variations within a group of cells can create significant difference in performance and failure.

As part of an effort to advance the performance of Li metal batteries and specifically to increase specific energy closer to 500 Wh/kg recent work looking at the ability to more clearly understand and define the role that cell variability has on the performance of Li metal batteries has been undertaken. This work has shown that significant impact to performance arises as a set of cells, which at the beginning of life had low variability, age. Refined analysis of the electrochemical data enables key variation in Li utilization and other fade mechanisms to be clearly identified and quantified across the different cells.

Complimentary work looking at the ability to fast charge, Li-ion cells in 10 minutes or less has also begun. This presentation will discuss the analysis methodology, key similarities in identifying the role of variability and how a more refined understanding can significantly impact the technology development pathway.