International Business Machines Corporation
Lithium energy storage device with composite anode

Abstract:

A Lithium energy storage device comprising a cathode, electrolyte, anode, and substrate. The materials contained in the anode and electrolyte region are electrochemically altered during initial formation and exposed to current cycles to create a lower impedance composite anode. The resulting composite anode bottom is a bi-layer comprising: i. a lithium metal layer and ii. a silicon-based interphase layer. The bi-layer acts as a barrier to inhibit Lithium ions from entering or leaving a Lithium saturated substrate, once the interphase surface is formed and the substrate is saturated with Lithium ions. This prevents cell failure from large volume changes/stresses during charge/discharge cycles and enables a significant decrease in cell impedance to enable better rechargeable cell performance.