Fig.1 Novel battery mechanism coupling high?capacity Li?containing anode and Li?free cathode based on alloy?dealloy reaction, illustrating the advantages of utilizing high?capacity Li?containing anodes
Fig.1 Novel battery mechanism coupling high?capacity Li?containing anode and Li?free cathode based on alloy?dealloy reaction, illustrating the advantages of utilizing high?capacity Li?containing anodes
Fig.2 Theoretical specific capacity and potential(vs. Li/Li+) of various high?capa? city Li?containing anodes and Li?free cathodes, in contrast to the conventional intercalation?type electrodes
Fig.2 Theoretical specific capacity and potential(vs. Li/Li+) of various high?capa? city Li?containing anodes and Li?free cathodes, in contrast to the conventional intercalation?type electrodes
Fig.3 Challenges faced by scientific research and practical fabrication on high?capacity Li?containing anode materials
Fig.3 Challenges faced by scientific research and practical fabrication on high?capacity Li?containing anode materials
Fig.4 Various synthesis methods to prepare LixMy anodes materials(A) High-temperature melting-solidification method to prepare LixSi NPs using Si NPs and molten Li. A dense passivation layer is formed on the surface of LixSi NPs after exposure to trace amounts of oxygen, preventing the LixSi alloy from further oxidation in dry air and showing good air stability[65]. (B) A two-step approach of coating- lithiation strategy to prepare stable LixSi-Li2O/TiyOz core-shell NPs[70]. (C) High-energy ball milling fabrication for Li4.4Si@LixNySiz anode[67]. (D) Schematic illustration of electrochemical lithiation for Si nanowires(NWs) and the internal electron and Li+ pathways during the lithiation[61]. (E) Schematic illustration of a pre-loaded Li3N cathode as the Li source for in situ electrochemical Li-Si alloying and pared with O2 cathode[91]. (F) Roll-to-roll lithiation method for the preparation of LixSn, LixAl and LixSi/C anode via stacking and rolling[71]. (G) Chemical lithiation for the preparation of Li-Al anode using polishing Al foil in the Li-DiMF solution[93].(A) Copyright 2014, Springer Nature; (B) Copyright 2018, American Chemical Society; (C) Copyright 2017, American Chemical Society; (D) Copyright 2011, American Chemical Society; (E) Copyright 2018, Royal Society of Chemical; (F) Copyright 2019, Royal Society of Chemical; (G) Copyright 2020, Royal Society of Chemistry.
Fig.4 Various synthesis methods to prepare LixMy anodes materials(A) High-temperature melting-solidification method to prepare LixSi NPs using Si NPs and molten Li. A dense passivation layer is formed on the surface of LixSi NPs after exposure to trace amounts of oxygen, preventing the LixSi alloy from further oxidation in dry air and showing good air stability[65]. (B) A two-step approach of coating- lithiation strategy to prepare stable LixSi-Li2O/TiyOz core-shell NPs[70]. (C) High-energy ball milling fabrication for Li4.4Si@LixNySiz anode[67]. (D) Schematic illustration of electrochemical lithiation for Si nanowires(NWs) and the internal electron and Li+ pathways during the lithiation[61]. (E) Schematic illustration of a pre-loaded Li3N cathode as the Li source for in situ electrochemical Li-Si alloying and pared with O2 cathode[91]. (F) Roll-to-roll lithiation method for the preparation of LixSn, LixAl and LixSi/C anode via stacking and rolling[71]. (G) Chemical lithiation for the preparation of Li-Al anode using polishing Al foil in the Li-DiMF solution[93].(A) Copyright 2014, Springer Nature; (B) Copyright 2018, American Chemical Society; (C) Copyright 2017, American Chemical Society; (D) Copyright 2011, American Chemical Society; (E) Copyright 2018, Royal Society of Chemical; (F) Copyright 2019, Royal Society of Chemical; (G) Copyright 2020, Royal Society of Chemistry.
Fig.5 Air?stable and freestanding lithium alloy/graphene foil anodes[68](A) Unique foil structure comprising densely packed reactive LixM nanoparticles encapsulated by large graphene sheets; (B) voltage profiles; (C) rate capability of LixSi/graphene||LiFePO4 full cell and Li||LiFePO4(LiFePO4/Super P/PVDF mass ratio of 70∶20∶10, 1C=170 mA/g of LiFePO4); (D) first-cycle voltage profiles; (E) cycling performance of LixSi/graphene||V2O5 full cell(red) and Li||V2O5(V2O5 nanosheets/Super P/PVDF mass ratio of 70∶20∶10) half cell(blue) at the rate of 1C. The capacity and rate are both based on the mass of V2O5 nanosheets in the cathode. The mass ratio of anode to cathode is 1∶4. The purple curve is the Coulombic efficiency of the LixSi/graphene||V2O5 full cell.Copyright 2017, Springer Nature.
Fig.5 Air?stable and freestanding lithium alloy/graphene foil anodes[68](A) Unique foil structure comprising densely packed reactive LixM nanoparticles encapsulated by large graphene sheets; (B) voltage profiles; (C) rate capability of LixSi/graphene||LiFePO4 full cell and Li||LiFePO4(LiFePO4/Super P/PVDF mass ratio of 70∶20∶10, 1C=170 mA/g of LiFePO4); (D) first-cycle voltage profiles; (E) cycling performance of LixSi/graphene||V2O5 full cell(red) and Li||V2O5(V2O5 nanosheets/Super P/PVDF mass ratio of 70∶20∶10) half cell(blue) at the rate of 1C. The capacity and rate are both based on the mass of V2O5 nanosheets in the cathode. The mass ratio of anode to cathode is 1∶4. The purple curve is the Coulombic efficiency of the LixSi/graphene||V2O5 full cell.Copyright 2017, Springer Nature.
Fig.6 Li3P/C nanocomposite for high?capacity lithium?containing anode[72](A) Schematic illustrates that Li3P nanoclusters are embedded in the nanopores of the carbon particles. The interconnected carbon framework of the porous carbon works as the conductive skeleton for fast electron transport. The ultrafine particle size of Li3P enables fast electrochemical reactions. The volume change of Li3P/P active material is confined within the nanopores of the carbon particles and stable SEI layer is formed at the outer surface of the Li3P/C composite particle during cycling; (B) cycling of the Li3P/C electrode cycled at various lithiation current densities with a constant delithiation current density of 0.2C; (C), (D) the corresponding voltage-capacity plots. The galvanostatic charge/discharge measurement for Li3P/C||Li metal cells was carried out with the cut-off potential range of 0.01―2 V.Copyright 2020, Springer Nature.
Fig.6 Li3P/C nanocomposite for high?capacity lithium?containing anode[72](A) Schematic illustrates that Li3P nanoclusters are embedded in the nanopores of the carbon particles. The interconnected carbon framework of the porous carbon works as the conductive skeleton for fast electron transport. The ultrafine particle size of Li3P enables fast electrochemical reactions. The volume change of Li3P/P active material is confined within the nanopores of the carbon particles and stable SEI layer is formed at the outer surface of the Li3P/C composite particle during cycling; (B) cycling of the Li3P/C electrode cycled at various lithiation current densities with a constant delithiation current density of 0.2C; (C), (D) the corresponding voltage-capacity plots. The galvanostatic charge/discharge measurement for Li3P/C||Li metal cells was carried out with the cut-off potential range of 0.01―2 V.Copyright 2020, Springer Nature.
Fig.7 Li?Al alloy anodes for novel battery configuration[77](A) Working mechanism of Li metal and Li-Al alloy anodes. The interface stability of Al-Li alloy is superior to Li metal in polysulphide solution, which is attributed to the protection by the implantable SEI layer formed during the electrochemical alloying. The SEM image shows the dense cross-section of the immersed Al-Li alloy foil; (B) full cell Al-Li alloy||Li2S4-C(HTC-CC); (C) self-discharge test of the Al-Li||HTC-CC and Li||HTC-CC full cells; (D) coulombic efficiency; (E) capacities of the Al-Li||HTC-CC, Li||HTC-CC and Al-Li||CC full cells upon 100 cycles.Copyright 2018， Royal Society of Chemistry.
Fig.7 Li?Al alloy anodes for novel battery configuration[77](A) Working mechanism of Li metal and Li-Al alloy anodes. The interface stability of Al-Li alloy is superior to Li metal in polysulphide solution, which is attributed to the protection by the implantable SEI layer formed during the electrochemical alloying. The SEM image shows the dense cross-section of the immersed Al-Li alloy foil; (B) full cell Al-Li alloy||Li2S4-C(HTC-CC); (C) self-discharge test of the Al-Li||HTC-CC and Li||HTC-CC full cells; (D) coulombic efficiency; (E) capacities of the Al-Li||HTC-CC, Li||HTC-CC and Al-Li||CC full cells upon 100 cycles.Copyright 2018， Royal Society of Chemistry.
Fig.8 An initial prototype of lithium ion?air battery[63](A) Novel lithium ion-air battery consisting of a lithiated-silicon anode and a carbon-oxygen cathode; (B) voltage profiles for the first galvanostatic cycle(B) and the following cycles(C), and the corresponding capacity-cycle number plots for the lithiated-silicon/carbon-oxygen cell(D).Copyright 2012, American Chemical Society.
Fig.8 An initial prototype of lithium ion?air battery[63](A) Novel lithium ion-air battery consisting of a lithiated-silicon anode and a carbon-oxygen cathode; (B) voltage profiles for the first galvanostatic cycle(B) and the following cycles(C), and the corresponding capacity-cycle number plots for the lithiated-silicon/carbon-oxygen cell(D).Copyright 2012, American Chemical Society.