Electrode/Electrolyte Interface of All Garnet Solid State Li-ion Batteries Topic Area: 7.2 (Electrochemistry)
Abstract
The objective of the proposed research is to establish the relationship between the three-dimensional (3-D) interphase structure, the interface impedance, and the electrochemical behavior of the all-garnet solid-state systems. These investigations will enable the characterization of different sources of interfacial resistance, advancing the current understanding of the solid-solid electrode/electrolyte interface. In the proposed research, a co-sintered all-garnet bulk-type solid-state battery consisting of garnet anode Li3Nd3W2012 (LNWO), garnet electrolyte Li7La3Zr2012 (LLZO), and garnet cathode Li0 75LaFe0.1402.09 (LLFO) with the same structure will be used as a model battery for the interfacial structure and impedance analysis. A porous LNWO, dense LLZO, and porous LLFO triple layer will be fabricated for the all-garnet solid state battery, wherein the thin and dense layer of solid electrolyte in the middle will provide a fast ionic conduction, and the porous structure of the electrodes will allow the carbon impregnation to increase the electronic conductivity of the electrodes. The micro/macro-structure at electrode/electrolyte interface in the all-garnet bulk-type all-solid-state lithium-ion battery will be investigated using novel 3-D reconstruction techniques by combining a focused-ion beam/scanning electron microscope (FIB/SEM) with an absorption contrast synchrotron X-ray nanotomography. The 3-D reconstruction of the interface will permit the investigation of the interface both at a macro-scale (porosity, interfacial crack, electrode/electrolyte contact, new interphase formation, and volume change of the electrodes), and at a micro-scale (the elemental mapping, the chemical state of the elements, and the local structure of the electrodes and electrolyte). The interfaces of the LLFO/LLZO/LNWO full cell, LLFO/LLZO/Li and LNWO/LLZO/Li half-cells will be studied at different stages of charge and different charge/discharge cycles. The relationship between macro/micro interfacial structure and non-destructive electrochemical impedance spectroscopy (EIS) will make the EIS a powerful tool for design, diagnosis, and prognostics of all-solid-state batteries. These investigations will present the distinction or tentative-quantification of different sources of interfacial resistance, advancing the current understanding of the solid-solid electrode/electrolyte interface. The fundamental knowledge gained from the interface of the all-garnet batteries can be applied to other all-solid-state energy storage devices.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 12, 2017
- Source ID
- W911NF1510187
Entities
People
- Chunsheng Wang
Organizations
- Army Contracting Command
- United States Army
- University of Maryland