Scalable silicon anodes and the role of parylene films in improving electrode performance characteristics in energy storage systems
A lithium-based energy storage system includes an electrolyte and an electrode. The electrode has a conformal coating of parylene. The parylene forms an artificial solid electrolyte interface (SEI). The electrode may include a material chosen from silicon, graphene-silicon composite, carbon-sulfur, and lithium. The use of parylene to form a conformal coating on an electrode in a lithium-based energy storage system is also disclosed.
1. An energy storage system comprising:
an electrolyte; and
an electrode, wherein the electrode comprises nanostructured silicon or a graphene-silicon composite having a thickness greater than 300 nm, and a conformal parylene coating on the electrode forming a physical barrier preventing contact between the electrode and the electrolyte;
wherein the parylene coating has a thickness ranging from about 1 nm to about 20 nm.
2. The energy storage system according to claim 1 , wherein the electrode further comprises a material chosen from carbon-sulfur, or lithium.
3. The energy storage system according to claim 2 , wherein the electrode further comprises a carbon-sulfur material.
4. The energy storage system according to claim 2 , wherein the electrode further comprises lithium.
5. The energy storage system according to claim 1 , wherein the nanostructured silicon or graphene-silicon composite has a void density of at least 20%.
6. The energy storage system according to claim 5 , wherein the void density is at least 30%.
7. The energy storage system according to claim 1 , wherein the nanostructured silicon has a spiral geometry.
8. The energy storage system according to claim 1 , further comprising a current collector and an adhesion promoting layer positioned between the current collector and the nanostructured silicon or graphene-silicon composite.
9. The energy storage system according to claim 8 , wherein the adhesion promoting layer comprises chromium or titanium.
10. The energy storage system according to claim 1 , wherein the parylene is chosen from parylene N, parylene C, or parylene AF-4.
11. An energy storage system comprising:
an electrolyte;
an electrode comprising nanostructured silicon or a graphene-silicon composite having a thickness greater than 300 nm; and
a parylene coating forming a physical barrier preventing contact between the electrode and the electrolyte.
12. The energy storage system according to claim 11 , wherein the nanostructured silicon or graphene-silicon composite has a thickness of at least 1 μm.
13. The energy storage system according to claim 11 , wherein the nanostructured silicon or graphene-silicon composite has a void density of at least 20%.
14. The energy storage system according to claim 13 , wherein the void density is at least 30%.
15. The energy storage system according to claim 11 , wherein the nanostructured silicon has a spiral geometry.
16. The energy storage system according to claim 11 , further comprising a current collector and an adhesion promoting layer positioned between the current collector and the nanostructured silicon or graphene-silicon composite.
17. The energy storage system according to claim 16 , wherein the adhesion promoting layer comprises chromium or titanium.
18. The energy storage system according to claim 11 , wherein the parylene coating has a thickness ranging from about 1 nm to about 20 nm.
19. The energy storage system according to claim 11 , wherein the parylene is chosen from parylene N, parylene C, or parylene AF-4.