High Capacity Electrodes for Li-ion Cells
Rojeski Research Engineering and Design, US
Keywords: lithium, ion, electrodes, nano
Abstract:Lithium-ion battery technology has received considerable attention over the last several years. In particular, silicon has risen to the forefront as a possible anode alternative to graphite. Nano-pillars, nano-wires, micro-porous silicon, and silicon nano-particles embedded in a binder matrix are several methods employed to use silicon as an anode material. To varying degree, each suffers from four disadvantages: volume expansion of the intercalation material, poor adhesion to the substrate, inability to appropriately flex the electrode after the intercalation material is in place, and insufficient deposited intercalation material to achieve high total energy density. To address these issues, a new nano-electrode technology has been developed that improves adhesion to a flexible substrate while allowing for volume expansion of a wide range of total deposited intercalation material. Cyclic voltammetry (CV) and cycle-life testing demonstrates an approximate 4X improvement in energy density, and a capacity fade of <35% at 600 cycles. Further fabrication runs will demonstrate the utility of the design for a cathode, with eventual inclusion of both electrode designs into an 18650 form-factor battery. The energy density from the 18650 cell is expected to be in excess of 3.6 Ah, with a cycle life in excess of 1000 cycles.