Lithium solid electrolyte and method of manufacture thereof
A method of manufacturing a lithium solid electrolyte, the method including: providing a composition including a lithium precursor, a lanthanum precursor, and a zirconium precursor; disposing the composition on a substrate having a temperature of 270° C. to 500° C. to form a film; and heat-treating the film at 300° C. to less than 750° C. for 1 hour to 100 hours to manufacture the lithium solid electrolyte.
1. A method of manufacturing a lithium solid electrolyte, the method comprising:
dissolving a lithium precursor, a lanthanum precursor, and a zirconium precursor in a solvent comprising an alcohol and a phthalate to form a solution;
disposing the solution on a substrate having a temperature of 270° C. to 500° C. to form a film; and
heat-treating the film at 300° C. to less than 750° C. to manufacture the lithium solid electrolyte,
wherein the phthalate is a substituted phthalate.
2. The method of claim 1 , wherein a content of the alcohol is 5 to 95volume percent, and a content of the phthalate is 95 to 5 volume percent, each based on a total volume of the solvent.
3. The method of claim 1 , wherein a content of the alcohol is 20 to 80 volume percent, and a content of the phthalate is 80 to 20 volume percent, each based on a total volume of the solvent.
4. The method of claim 1 , wherein a content of the alcohol is 30 to 70volume percent, and a content of the phthalate is 70 to 30 volume percent, each based on a total volume of the solvent.
5. The method of claim 1 , wherein the alcohol comprises at least one of methanol, ethanol, isopropanol, or butanol.
6. The method of claim 1 , wherein the solution further comprises a Ca precursor, a Mg precursor, an Al precursor, a Ga precursor, or a combination thereof.
7. The method of claim 1 , wherein the lithium precursor is contained in the solution in an amount corresponding to a stoichiometric excess for a compound of Formula 1
Li (7.2-2x-3y) A x M y La 3 Zr 2 O 12 (1)
wherein A is Ca or Mg, M is Al or Ga, and wherein 0≤x≤0.5 and 0≤y≤0.5,
relative to a content of the lanthanum precursor, the zirconium precursor, and the Ca precursor, the Mg precursor, the Al precursor and the Ga precursor, if present.
8. The method of claim 7 , wherein the stoichiometric excess is 1% to 300%.
9. The method of claim 1 , wherein the lanthanum precursor and the zirconium precursor are contained in the solution in an amount corresponding to a stoichiometric amount for a compound of Formula 1
Li (7.2-2x-3y) A x M y La 3 Zr 2 O 12 (1)
wherein A is Ca or Mg, M is Al or Ga, and wherein 0≤x≤0.5 and 0≤y≤0.5,
relative to a content of the lanthanum precursor, the zirconium precursor, and the Ca precursor, the Mg precursor, the Al precursor, and the Ga precursor, if present.
10. The method of claim 1 , wherein a concentration of the lithium precursor, the lanthanum precursor, and the zirconium precursor is 0.01 molar to 0.1 molar, based on the compound of Formula 1
Li (7.2-2x-3y) A x M y La 3 Zr 2 O 12 (1)
wherein A is Ca or Mg, M is Al or Ga, and wherein 0≤x≤0.5 and 0≤y≤0.5.
11. The method of claim 1 , wherein the disposing of the solution comprises spraying the solution.
12. The method of claim 11 , wherein the spraying comprises using air as a carrier gas.
13. The method of claim 11 , wherein the spraying comprises spraying with a pressure at an atomizer of 0.01 megaPascal to 0.1 megaPascal.
14. The method of claim 11 , wherein the spraying comprises spraying in air at an ambient pressure.
15. The method of claim 1 , wherein the heat-treating comprises heat-treating at 450° C. to 550° C.
16. The method of claim 1 , wherein the lithium solid electrolyte has a thickness of 0.1 μm to 10 μm.
17. The method of claim 1 , wherein the lithium solid electrolyte has a degree of crystallinity of 50% to 99%.
18. The method of claim 1 , wherein the lithium solid electrolyte has a local stress 10 megaPascals to 10 gigaPascals, when determined by multi-beam optical sensing.
19. The method of claim 1 , wherein the lithium solid electrolyte has a residual stress of 10 megaPascals to 10 gigaPascals, when determined by multi-beam optical sensing.
20. The method of claim 1 ,
wherein the lithium solid electrolyte has a peak in a Raman spectrum that corresponds to a peak in cubic Li 7 La 3 Zr 2 O 12 phase between 350 cm −1 and 400 cm −1 , and
wherein the peak in the Raman spectrum of the lithium solid electrolyte occurs at a wavenumber between 0 cm −1 and 50 cm −1 greater than a wavenumber of the corresponding peak in cubic Li 7 La 3 Zr 2 O 12 .
21. A method of manufacturing a lithium solid electrolyte, the method comprising
dissolving a lithium precursor, a lanthanum precursor, and a zirconium precursor in a solvent comprising an alcohol and a phthalate to form a solution;
disposing the solution on a substrate having a temperature of 270° C. to 500° C. to form a film; and
heat-treating the film at 300° C. to less than 750° C. to manufacture the lithium solid electrolyte,
wherein the phthalate comprises bis (2-ethylhexyl) phthalate.