Garnet materials for Li secondary batteries and methods of making and using garnet materials
Set forth herein are garnet material compositions, e.g., lithium-stuffed garnets and lithium-stuffed garnets doped with alumina, which are suitable for use as electrolytes and catholytes in solid state battery applications. Set forth herein are lithium-stuffed garnet thin films having fine grains therein. Disclosed herein are novel and inventive methods of making and using lithium-stuffed garnets as catholytes, electrolytes and/or anolytes for all solid state lithium rechargeable batteries. Disclosed herein are novel electrochemical devices which incorporate these garnet catholytes, electrolytes and/or anolytes. Set forth herein are methods for preparing novel structures, including dense thin free standing membranes of an ionically conducting material for use as a catholyte, electrolyte, and, or, anolyte, in an electrochemical device, a battery component (positive or negative electrode materials), or a complete solid state electrochemical energy storage device. The methods set forth herein disclose novel sintering techniques for solid state energy storage devices and the components thereof.
1. A composition comprising a lithium stuffed garnet and Al 2 O 3 ,
wherein the lithium-stuffed garnet is characterized by the empirical formula Li A La B M′ C M″ D Zr E O F , wherein 5<A<8, 1.5<B<4, 0.4<C≤2, O<D≤2; 1≤E≤2, 10<F≤15, and
M′ is Al; and
M″ is selected from Mo, W, Nb, Sb, Ca, Ba, Sr, Ce, Hf, and Rb.
2. The composition of claim 1 , wherein the composition is characterized by the empirical formula Li 7.0 La 3 Zr t1 Nb t2 O 12 0.35Al 2 O 3 ; wherein t1+t2 =2.
3. A composition comprising a lithium-stuffed garnet and Al 2 O 3 , wherein the lithium-stuffed garnet is characterized by the empirical formula Li A La B M′ C M″ D Zr E O F , wherein 6.5<A<8, 1.5<B<4, 0.4<C≤2, 0<D≤2; 1≤E≤2, 10<F≤15, and
M′ is Al; and
M″ is Ta.
4. The composition of claim 1 , wherein E is 1, 1.5, or 2.
5. The composition of claim 1 , wherein the molar ratio of Garnet:Al 2 O 3 is between 1:0.1 and 1:0.65.
6. The composition of claim 1 , wherein the molar ratio of Garnet:Al 2 O 3 is between 1:0.15 and 1:0.55.
7. The composition of claim 1 , wherein the molar ratio of Garnet:Al 2 O 3 is between 1:0.25 and 1:0.45.
8. The composition of claim 1 , wherein the subscript values represent elemental molar ratios of the precursor chemicals used to make the claimed composition.
9. The composition of claim 1 , wherein the composition is a thin film having a film thickness of about 10 nm to about 100 μm.
10. The composition of claim 9 , wherein the thickness is less than 20 μm and greater than 10 nm.
11. The composition of claim 9 , wherein the film has grains having a d 50 diameter less than 10 μm.
12. The composition of claim 9 , wherein the film has grains having a d 50 diameter less than 5 μm.
13. The composition of claim 9 , wherein the film has grains having a d 50 diameter less than 2 μm.
14. The composition of claim 9 , wherein the film has grains having a d 50 diameter less than 1 μm.
15. An energy storage device comprising an electrolyte comprising the composition of claim 1 .
16. An electrochemical device comprising a catholyte comprising the composition of claim 1 .