Lithium-ion Batteries Enabled by Silicon Anodes

Cover
Contents
List of figures
List of tables
About the editors
Foreword
1 Overview of the development of silicon anodes for lithium-ion batteries
	1.1 Introduction
		1.1.1 Siilicon-based Li-anode materials
		1.1.2 Conventional graphite anodes
		1.1.3 Why Si?
	1.2 Electrochemical insertion of Li in Si
	1.3 Si-based materials design
		1.3.1 Li15Si4 suppression
		1.3.2 Fracture suppression
			1.3.2.1 Si-transition metal (Si-M) alloys
			1.3.2.2 SiO
			1.3.2.3 Si-C
	1.4 Electrolyte additives
	1.5 Binders
		1.5.1 Electrochemically active binders
		1.5.2 Electrochemically inactive binders
	1.6 Implementation of Si alloys in Li-ion cells
	References
2 Application of Zintl–Klemm rules to silicon-based LIB anodes
	2.1 Energy storage
	2.2 Zintl–Klemm rules
	2.3 Structural considerations
	2.4 Binary Zintl phase reactivity
	2.5 Ternary Zintl phases
	2.6 Electrochemical characterization of the Si-based Zintl phase compounds
	2.7 Conclusions
	Acknowledgements
	References
3 Electrochemistry of silicon
	3.1 Introduction
	3.2 High-temperature Li−Si phases
	3.3 Room-temperature electrochemical (de)lithiation of Si and corresponding phase changes
		3.3.1 Difference between room- and high-temperature Si electrochemistry
		3.3.2 Structural evolution during the first lithiation and delithiation
	3.4 Anisotropic expansion of Si during lithiation
	3.5 Lithiation mechanism in Si
		3.5.1 Atomic mechanism of Li insertion into crystalline Si
		3.5.2 Atomic mechanism of Li insertion into amorphous Si
		3.5.3 Localized phase transformation during lithiation and delithiation
			3.5.3.1 Possible lithium silicide phases and their characteristics
			3.5.3.2 Phase transformation during first lithiation
			3.5.3.3 Phase transformation during first delithiation
			3.5.3.4 Phase transformation during second and following lithiation
			3.5.3.5 Phase transformation during delithiation of intermediate lithiated phases
		3.5.4 Effect of surface oxide on electrochemical reactions
		3.5.5 Species evolution during lithiation/delithiation of Si
	3.6 Outlook
	References
4 Electrolytes used in silicon anodes
	4.1 Electrolytes based on aprotic solutions
		4.1.1 Lithium salts
		4.1.2 Aprotic organic solvents
			4.1.2.1 Carbonates
			4.1.2.2 Ethers
			4.1.2.3 Other aprotic solvents
		4.1.3 Electrolyte additives
	4.2 Electrolytes based on ionic liquid solutions
	4.3 Solid-state electrolytes
		4.3.1 Ceramic-based SSEs
		4.3.2 Polymer-based SSEs or solid-state polymer electrolytes
		4.3.3 Gel polymer electrolyte
		4.3.4 Materials other than electrolytes used
	4.4 Perspective
	References
5 Interfacial chemistry on silicon anode
	5.1 Introduction
	5.2 SEI formation mechanisms
	5.3 The effect of electrolyte solvent and salt on Si SEI formation
		5.3.1 Reduction of solvent molecules
			5.3.1.1 Reduction of the cyclic carbonate—ethylene carbonate
			5.3.1.2 Reduction of linear carbonates
		5.3.2 Reduction of lithium salt
	5.4 The effect of electrolyte additives on Si SEI formation
		5.4.1 Carbonate solvent additive—FEC
		5.4.2 Carbonate solvent additive—VC
	5.5 SEI characterization techniques
		5.5.1 Morphological methods
			5.5.1.1 Optical microscopy
			5.5.1.2 Electron microscopy
			5.5.1.3 Scanning probe microscopy
		5.5.2 Surface chemistry
			5.5.2.1 Infrared spectroscopy
			5.5.2.2 Confocal microscope Raman spectroscopy
			5.5.2.3 X-ray photoelectron spectroscopy
			5.5.2.4 Time-of-flight secondary ion mass spectrometry
	5.6 Summary
		5.6.1 Silicon SEI models
		5.6.2 Outlook
	Acknowledgment
	References
6 Computational studies for understanding and developing silicon anodes
	6.1 Introduction
	6.2 Brief review of computational methodology
	6.3 Si anode properties characterized by computational methods
		6.3.1 Si anode lithiation
		6.3.2 Si clusters: stability, lithiation, and interaction with electrolyte components at low degrees of lithiation
		6.3.3 Effect of higher lithiation and surface facet structure on the reductive decomposition of solvents, additives, and salts of electrolyte solutions
		6.3.4 Effects of Si crystallinity and oxidation degrees on the SEI reactions
		6.3.5 Allotropes of silicon and implications for the SEI layer formation
	6.4 Consequences of volume expansion and potential solutions
		6.4.1 Mechanical stresses and particle cracking
		6.4.2 Artificial SEI layers and other anode protection strategies
	6.5 Conclusions and future work
	References
7 Nanostructure silicon for Li-ion batteries
	7.1 Introduction
	7.2 Opportunities and challenges for Si anodes
	7.3 Synthesis and nanoeffect of nanostructured Si anodes
		7.3.1 0D Si nanostructure
		7.3.2 1D Si nanostructure
		7.3.3 2D Si nanostructure
		7.3.4 3D Si nanostructure
	7.4 Synthesis and nanoeffect of nanostructured Si-based composite anodes
		7.4.1 Si/amorphous carbon composites
		7.4.2 Si/graphitic carbon composites
		7.4.3 Si/conductive polymer composites
		7.4.4  Si/metal or oxide composites
	7.5 Si-based nanostructure anodes for high-energy full cells
		7.5.1 Si-based anode paired with LMO cathode
		7.5.2 Si-based anode paired with sulfur-based cathode
	7.6 Summary and outlook
	References
8 Binder additive for silicon anodes
	8.1
 Introduction
	8.2
 The functionality of binders in a composite electrode
		8.2.1 Fundamentals of adhesion
		8.2.2 The battery electrode as a unique polymer composite
	8.3 Surfaces of Si materials
	8.4 Commercial binders: PVDF and CMC/SBR
	8.5 New functional binders
		8.5.1 Design principles for Si electrode binders
		8.5.2 Development of adhesive binders
		8.5.3 Development of elastic binders
		8.5.4 Development of conductive binders
	8.5 Development of water-soluble or dispersible binders
	8.6 Additional considerations
	References
9 Surface modification for silicon anodes
	9.1 Introduction
	9.2 Materials and techniques for surface modification
		9.2.1 Carbonaceous material coatings
			9.2.1.1 Carbon coatings via pyrolysis of polymers
			9.2.1.2 Carbon coating via chemical vapor deposition
			9.2.1.3 Effects of carbon coating on conductivity and SEI composition
		9.2.2 Si-metal alloy modification
			9.2.2.1 Si-metal as a Li-active material
			9.2.2.2 Si as a Li-active material
		9.2.3 Surface modification via ALD and MLD
			9.2.3.1 Introduction
			9.2.3.2 Surface modifications via MLD on Si-based anodes
		9.2.4 In situ Li–M–Si phase formation using additional salt
	References
10 Mechanical characterization of silicon-based electrodes
	10.1 Nanoindentation
		10.1.1 Instrumented nanoindentation technique
		10.1.2 Mechanical property evolution of LixSi alloys during electrochemical cycling
		10.1.3 Mechanical property evolution of Si composite electrodes
	10.2 Scratch tests
	10.3 Peel tests
	10.4 In situ stress measurements
		10.4.1 Multi-beam optical stress sensor (MOSS)
		10.4.2 In situ curvature measurements of cantilever electrodes
	10.5 Fracture behavior of Si-based electrodes
		10.5.1 Si wafer electrodes
		10.5.2 Si thin film electrodes
		10.5.3 Si composite electrodes
	10.6 Summary
	Acknowledgments
	References
11 Practical implementation of silicon-based negative electrodes in lithium-ion full-cells—challenges and solutions
	11.1 Introduction
		11.1.1 Lessons learned from commercialized battery cells based on lithium-alloying anodes
		11.1.2 Can we directly transform the knowledge gained from graphite anodes to Si anodes?
	11.2 Impact of Si-addition to lithium-ion cells: performance and application
		11.2.1 Key metrics for practical Si anode-based lithium-ion cells
			11.2.1.1 Cycle and calendar life
			11.2.1.2 Efficiencies of redox reactions: impact on cycle life and power (rate capability)
			11.2.1.3 Specific energy and energy density
			11.2.1.4 Cost: from material cost to cell cost
			11.2.1.5 Safety
		11.2.2 Impact of Si-addition on the performance characteristics of lithium-ion cells
		11.2.3 Silicon in commercial LIB cells: state of the art and markets for Si-based cells
	11.3 Challenges for practical implementation of Si-based negative electrodes in lithium-ion battery full-cells
		11.3.1 Studies of Si-based materials in Li metal cells: opportunities, pitfalls, and lessons learned
		11.3.2 Studies of Si-based materials in lithium-ion full-cells: considerations for anode/cathode capacity balancing and challenges with respect to active lithium losses
		11.3.3 Challenges for implementation Si-based materials in practical lithium-ion cell formats: electrolyte drying-out and electrode swelling
	11.4 Strategies for the development of advanced Si-based lithium-ion full-cells
		11.4.1 Material concepts toward practical usage of Si-based anodes
			11.4.1.1 Silicon/graphite blends as anode material
			11.4.1.2 Major recent results on Si-based LIB full-cells
		11.4.2 Electrode formulation and binder development
		11.4.3 Pre-treatment and pre-lithiation strategies for Si-based negative electrodes
		11.4.4 Electrolyte development
			11.4.4.1 Salt anions
			11.4.4.2 Electrolyte additives
	11.5 Conclusion and future perspectives
	References
12 A silicon future
	References
Index
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