Pile up - folded form electrode subassembly and secondary cell group is provided. The electrode subassembly who contains a plurality of stacked battery cell according to this disclosed piling up - folded form electrode subassembly, under the condition between each person during the battery cell who is piling up is intervene to in succession folding shim, battery cell piles up each other, battery cell has the combination of two four at least batteries and a C type double cell, four batteries are positive electrode / separator / negative electrode / separator / positive electrode / separator / burden electrode structure, C type double cell is negative electrode / separator / positive electrode / separator / burden electrode structure, and under the condition of four battery settings at the middle body, the setting has mutual asymmetrical structure at the battery cell of middle body or winding starting point top and below, or set up under the condition at the middle body at C type double cell, the battery cell of setting in middle body or winding starting point top and below has the structure of mutual symmetry.