A secondary battery includes an electrode assembly disposed within a constraint. The electrode assembly comprises a population of unit cells comprising an electrode current collector layer, an electrode layer, a separator layer, a counter-electrode layer, and a counter-electrode current collector layer in stacked succession. A subset of the unit cell population includes extended spacer members between the electrode current collector layer and the counter-electrode current collector layer. One of the spacer members is spaced in a transverse direction from the other extended spacer member, at least a portion of the counter-electrode active material of the counter-electrode layer being located between the spacer members such that the portion of the counter-electrode active material and the spacer members lie in a common plane defined by x and z axes, wherein each of the extended spacer members extend a distance SD in the x-axis direction beyond an x-axis edge of the constraint.