Embodiments described herein relate to electrochemical cell assemblies with structural members for application of compressive force. In some aspects, an electrochemical cell assembly can include a plurality of electrochemical cells arranged in a stack, a first planar sheet in contact with a first side of the stack, a second planar sheet in contact with a second side of the stack, a first structural member in compressive contact with the first planar sheet, and a second structural member in compressive contact with the second planar sheet, wherein the compressive contact between the first structural member and the first planar sheet and the compressive contact between the second structural member and the second planar sheet collectively provide structural rigidity to the electrochemical cell assembly.