Energy Conversion and Energy Storage Materials >Structural stability and electrochemical property of electrode materials for Li-ion batteries >Interface stability in All-solid-state lithium-ion batteries >HER and OER >
Energy Conversion and Energy Storage Materials ➢ Structural stability and electrochemical property of electrode materials for Li-ion batteries ➢ Interface stability in All-solid-state lithium-ion batteries ➢ HER and OER ➢ ……
Lithium ion Batteries (LiBs) Current→ U,I Li must be more stable in cathode than anode Electrons Voltage Anode Separator/Electrolyte Cathode Electrodes must accomodate sufficient Li Capacity Electrons must be extractable from electrodes oc OLi 拳b 复Tri8ul Conductivity Materials Devices Battery Voltage x capacity Energy Anode Cathode Power 3C Industry Militark Ele ctrolyte
Materials Devices Battery 3C Power Anode Cathode Industry Military Electrolyte + = Lithium ion Batteries ( Lithium ion Batteries (LiBs) LiBs)
Electrode Structures Layered compounds LiMO, Spinal compounds LiM2O4 Olivine compounds LiMPO MO2slab The oxygen anions form a close- The oxygen framework is the same slightly distorted hcp anion packed fcc lattice; as that of LiMO2 layered structure. oxygen arrays with 12 Fe- cations located in the 6-coordinated M cations occupy the octahedral octahedral sites and 1/8 Li sites. octahedral crystal site. site but 1/4 of them are located in √ The LiOs octahedra are edge- The MO2 slabs and Li layers are the Li layer,leaving 1/4 of the sites shared while the FeOs octahedra stacked alternatively. in TM layer vacant. are corner-shared. Li ions occupy the tetrahedral sites LiOs and FeOs run parallel to the c in Li layer that share faces with the axis and alternate in b direction. empty octahedral sites in the The a-c planes containing Li are transition metal layer. bridged by PO4 tetrahedral
Electrode Structures Layered compounds LiMO2 Spinal compounds LiM2O4 Olivine compounds LiMPO4 ❖ The oxygen framework is the same as that of LiMO2 layered structure. ❖ M cations occupy the octahedral site but 1/4 of them are located in the Li layer, leaving 1/4 of the sites in TM layer vacant. ❖ Li ions occupy the tetrahedral sites in Li layer that share faces with the empty octahedral sites in the transition metal layer. ✓ slightly distorted hcp anion oxygen arrays with ½ Feoctahedral sites and 1/8 Li sites. ✓ The LiO6 octahedra are edgeshared while the FeO6 octahedra are corner-shared. ✓ LiO6 and FeO6 run parallel to the c axis and alternate in b direction. ✓ The a–c planes containing Li are bridged by PO4 tetrahedral. • The oxygen anions form a closepacked fcc lattice ; • cations located in the 6-coordinated octahedral crystal site. • The MO2 slabs and Li layers are stacked alternatively
Calculations on electrode materials LiTiO VF. +CoO,FeO A/o Graphene Ge Sn Si Lithium Graphite SWCNT 01000 2000300040005000 Capacity/mAh.g L Li First Principle Calculations Boltzman's constant M Electron Mass Phase diagram Electron Charge Interactions Planck Constant Light Velocity Experimental phenomena interpreting Diffusion
Calculations on electrode materials
Calculations on electrode materials Structural and chemical stabilities AEpper(phase,uM)=Eeg(Ceg(C,uM))-E(phase)-AnM'UM uLi(中)=2；-eφ， 2.5 231y GeS2 P2S 214y LiaPS4 LioGeRS122LiPS,+LiGeS 2.0 Stability Window LGPS LLGeSe 1.5 P LGPS 130V Li GeS GeS 117V LiP? PS GeS (A)a6eoA 1.0 Ge Li3Pr 093y P26 87 s Ge 0.561 Ge 0.5 045y LiGe LiP 028V LinGe (a) (b) (c) LitsGe4 0.0 0 400 800 1200 1600 Capacity(mAh g) Phase Equilibria
Structural and chemical stabilities Calculations on electrode materials