Battery cell assembly

The present invention provides a battery cell assembly. The battery cell assembly comprises: a polymer foam container including a first sidewall, a second sidewall and a third sidewall which define the inner region; and a first battery cell having a first rectangular main body portion together with a first circumferential ledge portion, a second circumferential ledge portion and a third circumferential ledge portion. The first sidewall and the second sidewall extend to be parallel to each other. The third sidewall extends between the first sidewall and the second sidewall and is perpendicular to the first sidewall and the second sidewall. The first sidewall, the second sidewall, and the third sidewall include a first groove, a second groove, and a third groove which respectively extend in the first sidewall, the second sidewall, and the third sidewall. The first circumferential ledge portion and the second circumferential portion of the first battery cell extend to be parallel to each other. The third circumf