Three-Dimensional Solid-State Lithium-Ion Batteries Fabricated by Conformal Vapor-Phase Chemistry

Abstract

Three-dimensional thin-film solid-state batteries (3D TSSB) were proposed by Long et al. in 2004 as a structure-based approach to simultaneously increase energy and power densities. Here, we report experimental realization of fully conformal 3D TSSBs, demonstrating the simultaneous power-and-energy benefits of 3D structuring. All active battery components-electrodes, solid electrolyte, and current collectors-were deposited by atomic layer deposition (ALD) onto standard CMOS processable silicon wafers microfabricated to form arrays of deep pores with aspect ratios up to approximately 10. The cells utilize an electrochemically prelithiated LiVO cathode, a very thin (40-100 nm) LiPON solid electrolyte, and a SnN anode. The fabrication process occurs entirely at or below 250 °C, promising compatibility with a variety of substrates as well as integrated circuits. The multilayer battery structure enabled all-ALD solid-state cells to deliver 37 μAh/cm·μm (normalized to cathode thickness) with only 0.02% per-cycle capacity loss. Conformal fabrication of full cells over 3D substrates increased the areal discharge capacity by an order of magnitude while simulteneously improving power performance, a trend consistent with a finite element model. This work shows that the exceptional conformality of ALD, combined with conventional semiconductor fabrication methods, provides an avenue for the successful realization of long-sought 3D TSSBs which provide power performance scaling in regimes inaccessible to planar form factor cells.

Addressing Interfacial Issues in Liquid-Based and Solid-State Batteries by Atomic and Molecular Layer Deposition

“…Figure 8B shows an optical photograph of the finished battery ''chip.'' 111 As shown in the cross-sectional TEM image in Figure 8C Figure 8D. Impressively, the 3D SSBs consisting of the LiV 2 O 5 -SnN x couple delivered stable capacities of 2.6 mAh cm À2 for a long lifetime of up to 100 cycles.…”

Atomic layer deposition of vanadium oxides: process and application review

“…The conformal nature of ALD allows the construction of very thin electrodes on highly structured 3D electrodes, such as (MW-)CNTs and silicon etch-based structures as pillars or trenches. This enables a very fast charging thanks to the reduced diffusion length in thin film and a considerable capacity attributed to the area enhancement factor of the substrate compared to the footprint area, [87], ultimately allowing the integration into 3D all-solid-state thin-film batteries, [109]. On the other hand, the excellent phase control and high quality of the films allows for the study of ALD vanadium oxides as 'model system' electrodes.…”

Tape‐Casting Li0.34La0.56TiO3 Ceramic Electrolyte Films Permit High Energy Density of Lithium‐Metal Batteries

“…And, thin‐film electrolytes and cathode layers need to be deposited/sputtered on a substrate. The energy density of thin‐film batteries is still low . Time‐consuming production and high costs further limit their application.…”