Encapsulated sulfur cathodes for rechargeable lithium batteries
A method of forming a sulfur-based cathode material includes: 1) providing a sulfur-based nanostructure; 2) coating the nanostructure with an encapsulating material to form a shell surrounding the nanostructure; and 3) removing a portion of the nanostructure through the shell to form a void within the shell, with a remaining portion of the nanostructure disposed within the shell.
1. A battery comprising:
an anode;
a cathode; and
an electrolyte disposed between the anode and the cathode,
wherein the cathode includes a hollow, polymer shell defining an internal volume and a sulfur-based material disposed within the internal volume, and the sulfur-based material occupies less than 100% of the internal volume to define a void.
2. The battery of claim 1 , wherein, in a substantially de-lithiated state of the sulfur-based material, a volume of the void is at least 1/3 of the internal volume.
3. The battery of claim 1 , wherein, in a substantially de-lithiated state of the sulfur-based material, a volume of the void is at least 2/3 of the internal volume.
4. The battery of claim 1 , wherein the sulfur-based material is configured as a hollow nanostructure, and the void is disposed within an interior of the hollow nanostructure.
5. The battery of claim 1 , wherein the sulfur-based material is configured as a nanostructure.
6. The battery of claim 1 , wherein at least a portion of the sulfur-based material directly contacts the hollow, polymer shell.
7. The battery of claim 1 , wherein the hollow, polymer shell is spheroidal.
8. The battery of claim 1 , wherein the hollow, polymer shell has an aspect ratio that is no greater than 3.
9. The battery of claim 1 , wherein the hollow, polymer shell has an aspect ratio that is no greater than 2.5.
10. The battery of claim 1 , wherein the hollow, polymer shell has an aspect ratio that is no greater than 2.
11. The battery of claim 1 , wherein the hollow, polymer shell includes a wall having a thickness in a range of 1 nm to 100 nm.
12. The battery of claim 1 , wherein the hollow, polymer shell includes a conductive polymer.
13. The battery of claim 12 , wherein the conductive polymer includes polar groups.
14. The battery of claim 1 , wherein the electrolyte includes an organic solvent.