Theoretical Study on Graphite and Lithium Metal as Anode Materials for Next-Generation Rechargeable Batteries

1 Introduction 1

1.1 Demands for energy storage system 1

1.2 Li-ion batteries 1

1.3 Post Li-ion batteries 3

1.3.1 Na-ion batteries 3

1.3.2 Li metal batteries 5

1.4 References 6

2 Na intercalation chemistry in graphite 9

2.1 Introduction 9

2.2 Experimental and computational details 10

2.2.1 Materials 10

2.2.2 Electrode preparation and electrochemical measurements 10

2.2.3 Operando XRD analysis 11

2.2.4 Computational details 11

2.3 Staging behavior upon Na-solvent co-intercalation 12

2.4 Na-solvent co-intercalation into graphite structure 15

2.5 Solvent dependency on electrochemical properties 20

2.6 Conclusions 24

2.7 References 27

3 Conditions for reversible Na intercalation in graphite 31

3.1 Introduction 31

3.2 Computational details 32

3.3 Unstable Na intercalation in graphite 33

3.3.1 Destabilization energy of metal reconstruction 35

3.3.2 Destabilization energy of graphite framework upon intercalation 37

3.3.3 Local interaction between alkali metal ions and the graphite framework 37

3.3.4 Mitigating the unfavorable local interaction between Na and graphene layers 39

3.4 Conditions of solvents for reversible Na intercalation into graphite 41

3.4.1 Solvent dependency on reversible Na-solvent co-intercalation behavior 41

3.4.2 Thermodynamic stability of Na-solvent complex &nbs