No, it’s not a massive coin cell

Though it looks like a stack of wildly oversized coin cells, Rolled-Ribbon battery modules actually have an internal make-up that differs dramatically from that of coin cells. Devised by Rolled-Ribbon Battery Co. in Austin, Tex., they are Li-ion cells whose internal components consist of ribbon-like material wound in a way analogous to that of cylindrical cells, but with a flattish form factor. This gives each cell a big surface area from which to disperse heat. Individual cells then get stacked to create a module. Besides good heat dissipation, the benefits include no need for welding the individual cells together, and a construction method that permits disassembling and servicing the modules. Cells are a little over an inch-thick at most and measure about 6.5-in. in diameter. A 48-V module can deliver about 28 A continuously.
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