Advanced Lithium-Ion Battery Failure Analysis—An Evolving Methodology for An Evolving Technology

Root cause failure analysis of lithium-ion batteries provides important feedback for cell design, manufacture, and use. As batteries are being produced with larger form factors and higher energy densities, failure analysis techniques must be adapted to characteristics of the specific batteries. This paper will discuss the significance of melted copper in lithium-ion battery cells that have experienced thermal runaway and how the interpretation of such evidence has evolved over time. Specialized testing techniques that may prove helpful in determining the root cause of battery failures will also be described.