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Advancing Focused Ion Beam Characterization for Next Generation Lithium-Ion Batteries

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Advancing Focused Ion Beam Characterization for Next Generation Lithium-Ion Batteries UC San Diego UC San Diego Electronic Theses and Dissertations Title Advancing Focused Ion Beam Characterization for Next Generation Lithium-Ion Batteries Permalink https://escholarship.org/uc/item/3sh5k04b Author Lee, Jungwoo Publication Date 2018 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA SAN DIEGO Advancing Focused Ion Beam Characterization for Next Generation Lithium-Ion Batteries A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in NanoEngineering by Jungwoo Zema Lee Committee in charge: Professor Ying Shirley Meng, Chair Professor David P. Fenning Professor Eric E. Fullerton Professor Olivia A. Graeve Professor Ping Liu 2018 Copyright Jungwoo Zema Lee, 2018 All rights reserved. The Dissertation of Jungwoo Zema Lee is approved, and it is acceptable in quality and form for publication on microfilm and electronically: Chair University of California San Diego 2018 iii DEDICATION To my given and chosen family iv TABLE OF CONTENTS Signature Page ..................................................................................................................... iii Dedication ............................................................................................................................ iv Table of Contents ................................................................................................................ v List of Abbreviations .......................................................................................................... vi ii List of Figures ...................................................................................................................... x List of Tables ....................................................................................................................... xv i Acknowledgements ............................................................................................................. xvii Vita ....................................................................................................................................... xx Abstract of the Dissertation ............................................................................................... xx ii Chapter 1. Introduction ..................................................................................................... 1 1.1 Motivation ................................................................................................................. 1 1.2 Lithium-Ion Batteries ................................................................................................ 3 1.3 Solid-State Batteries .................................................................................................. 9 Chapter 2. Previous Work on Solid-State Thin Film Batteries ...................................... 11 2.1 Solid-State Thin Film Batteries ................................................................................. 11 2.2 Thin Film Deposition Techniques ............................................................................. 11 2.3.1 Thermal Evaporation ..................................................................................... 12 2.3.2 Radio Frequency Sputtering ........................................................................... 15 2.3.3 Pulsed Laser Deposition ................................................................................ 18 2.3 Components of Thin Film Batteries .......................................................................... 20 2.3.1 Thin Film Cathodes......................................................................................... 20 2.3.2 Thin Film Anodes ............................................................................................ 24 2.3.3 Thin Film Electrolytes ..................................................................................... 26 2.4 Lithium-Ion Thin Film Devices ................................................................................ 29 2.5 Solid Electrode-Solid Electrolyte Interfaces ............................................................. 30 Chapter 3. Overview of Advanced Characterization Techniques .................................. 33 3.1. Focused Ion Beam ..................................................................................................... 33 3.2. Transmission Electron Microscopy ........................................................................... 38 v Chapter 4. Development of Amorphous Lithium Lanthanum Titanate Thin Films for Lithium-Ion Solid-State Batteries ............................................................................... 41 4.1.Introduction ................................................................................................................ 41 4.2. Experimental ............................................................................................................. 44 4.2.1 LLTO Synthesis ............................................................................................... 44 4.2.2 Pulsed Laser Deposition of LLTO .................................................................. 44 4.2.3 Electrochemical Testing.................................................................................. 45 4.2.4 Transmission Electron Microscopy ................................................................ 46 4.3. Results and Discussion .............................................................................................. 47 4.3.1 LLTO Target Characteristics .......................................................................... 47 4.3.2 Deposition Pressure Dependence ................................................................... 49 4.3.3 Deposition Temperature Dependence ............................................................. 51 4.3.4 Electrochemistry ............................................................................................. 56 4.4. Conclusion ................................................................................................................. 60 Chapter 5. Air-Free Mechanical Testing of LiPON Thin Film Solid-State Electrolyte ............................................................................................................................ 62 5.1.Introduction ................................................................................................................ 62 5.2. Experimental ............................................................................................................. 65 5.2.1 LiPON Deposition ........................................................................................... 65 5.2.2 Electrochemical and Chemical Characterization ........................................... 65 5.2.3 Mechanical Characterization ......................................................................... 66 5.3.Results and Discussion ............................................................................................... 68 5.3.1 Mechanical Properties of Li2CO3 ................................................................... 68 5.3.2 LiPON Stability in Mineral Oil ....................................................................... 70 5.3.3 Mechanical Properties of LiPON ................................................................... 72 5.3.4 LiPON Characterization ................................................................................. 74 5.4. Conclusion................................................................................................................. 81 Chapter 6. Focused Ion Beam Fabrication of Electrochemically Active LiPON- based Solid-State Lithium-Ion Nanobatteries for In Situ Testing .................................. 85 6.1.Introduction ................................................................................................................ 85 6.2. Experimental Protocol ............................................................................................... 87 6.2.1 Preparation of the Sample and System ........................................................... 87 6.2.2 Lift-Out Nanobattery ....................................................................................... 89 6.2.3 Clean and Cycle Nanobattery ......................................................................... 93 6.3. Results and Discussion .............................................................................................. 95 6.3.1 Cycling of LCO Nanobattery .......................................................................... 95 6.3.2 FIB Protocol Obstacles ................................................................................... 97 6.4.Conclusion .................................................................................................................. 101 vi Chapter 7. Cryogenic Focused Ion Beam Characterization of Lithium Metal Anodes for Lithium-Ion Batteries ..................................................................................... 102 7.1.Introduction ................................................................................................................ 102 7.2. Experimental ............................................................................................................. 104 7.2.1 Cryogenic Focused Ion Beam ......................................................................... 104 7.2.2 Electrochemical Sample Preparation ............................................................
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