Interfacial engineering of solid electrolytes

Synthesis and Properties of NaSICON‐type LATP and LAGP Solid Electrolytes

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Inorganic solid electrolytes, in comparison with their liquid counterparts, have more potential in varioust ypes of batteries due to their dual roles of ion transportation and separation. [7,8] In principle, ideal solid electrolytes are expected to have several features: [9][10][11][12][13][14] 1) fast ion dynamics and negligible electronic conductivity (minimum ionic conductivity of 10 À4 Scm À1 at room temperature for practical consideration);2 )a wide electrochemical potential window for battery cycling;3 )ane xceptional mechanical strength to suppress lithium dendrite growth;4 )excellent thermal stability during the cycling processes;and 5) asimple and low cost synthetic process for large-scale applications.Generally,i norganic lithium superionic conductors are divided into three categories:o xides, sulfides, and phosphates. Moreover,i norganic solid electrolytes are also beneficial for lithium-ion batteries and lithium-air batteries, in which they functiona se ither surface modification layers or lithium-ion conductors.

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Composites of sodium manganese oxides with enhanced electrochemical performance for sodium-ion batteries: Tailoring properties via controlling microstructure

“…In this work, the Na 0.44 MnO 2 phase is clearly the majority phase for both specimens (Figure 2), whereas the excess amounts of Na (since the Na/Mn ratios were measured to be 0.60 for both specimens) lead to the formation of secondary layer-structured phases with higher Na contents, which may affect the electrochemical performance of the composite electrodes as discussed subsequently. It is also possible that some Na-rich amorphous phases may form during the high-energy ball milling and heat treatments, either as bulk secondary phases or as 2-D interfacial phases (nanoscale surface [14][15][16][17][18][19] or intergranular [15,18,20] "amorphous" films), as shown in prior studies of lithium-ion battery materials that were made by similar ball milling and annealing processes [15][16][17][18][19].…”

“…Additional opportunities exist via utilizing nanometer-thick, amorphous-like, 2-D interfacial phases (that may form spontaneously after ball milling and annealing at surfaces [14][15][16][17][18][19] and grain boundaries [15,18,20]) to improve cycling stability or enhance the rate capabilities. Such strategies have been demonstrated successfully for many electrode materials for lithium-ion batteries [15][16][17][18][19][20] and we expect more opportunities exist for sodium-ion batteries to improve and tailor the electrochemical performance via controllably altering microstructures and interfaces, particularly for composite electrodes.…”

Suppressed phase transition and giant ionic conductivity in La2Mo2O9 nanowires

“…It is important to recognize that many possible mechanisms can lead to enhanced ionic conductivities, such as space-charge, strain and other effects2639404142434445. To some extent, the current case is analogous to the study of PVP-coated α-AgI, where both change of the interfacial energies and possible presence of charged defects at the crystal-amorphous interfaces may help stabilizing the high-temperature, high-conducting phase26.…”