Equivalent stiffness analysis of flexible lithium-ion batteries with repeated unit cell: A computational approach

Abstract

Flexible batteries have recently developed significant advancements in structural design, diverging substantially from traditional battery architectures. However, conventional mechanical testing methods and metrics, tailored for standard battery structures, prove inadequate when evaluating the flexibility of these innovative designs. How to assess the mechanical performance of diverse structural configurations of flexible batteries poses a considerable challenge. In this study, a general computational approach is proposed to evaluate the equivalent stiffness of flexible lithium ion batteries (FLIBs) by analyzing the force–deformation response of a repeated unit cell (RUC), thereby enabling a comprehensive comparison of different FLIB designs. Moreover, to further enhance their deformability, the interconnected supple components of FLIBs have been optimized. This research lays a critical foundation for comparing the mechanical performance and optimizing the design of flexible batteries in the future.