This paper considers the determination method of deformation location of lithium polymer batteries. Measurements are performed using the Digital Image Correlation (DIC) technique and the obtained results are sorted into a database as a function of the charge level. A statistically based algorithm is used to eliminate measurement errors and outliers. This paper adopts the Weighted Ordered Weighted Averaging (WOWA) operator-based 2D filtering method with the purpose of determining the critical regions of the cell. During the tests, several lithium polymer batteries of the same type but in different states are compared. Measurements on completely new and also on worn-out batteries are performed. The results support that the regions where greater deformation is expected during charging and discharging can be predicted. Results of investigations validate that the proposed approach is suitable for determining the critical deformation regions with high accuracy.