ASYMMETRIC AND SYMMETRIC ELECTROCHEMICAL ARRAYS

Electrochemical cell arrays such as battery packs having cells of different sizes and/or thicknesses is disclosed. For example, the cells in an array may progressively increase or decrease in size or thickness from a first end to a second end such that a gradient in thickness is created. Alternatively, the gradient may be from the center to the outside. In a variation, the first and second endplates may be of different sizes or thicknesses.