Energy storage devices
View Patent ↗A novel hybrid lithium-ion anode material based on coaxially coated Si shells on vertically aligned carbon nanofiber (CNF) arrays. The unique cup-stacking graphitic microstructure makes the bare vertically aligned CNF array an effective Li + intercalation medium. Highly reversible Li + intercalation and extraction were observed at high power rates. More importantly, the highly conductive and mechanically stable CNF core optionally supports a coaxially coated amorphous Si shell which has much higher theoretical specific capacity by forming fully lithiated alloy. Addition of surface effect dominant sites in close proximity to the intercalation medium results in a hybrid device that includes advantages of both batteries and capacitors.
1. An energy storage system comprising:
a first electrode disposed in a first region of electrolyte and including
a substrate including carbon nanofibers, and
an ion adsorbing material attached to the substrate, the ion adsorbing material including an intermetallic and including nanoparticles;
a separator configured to separate the first region and a second region of electrolyte; and
a second electrode disposed in the second region of electrolyte, the first and second electrodes and separator configured to operate as an energy storage device.
2. The system of claim 1 , wherein the intermetallic includes silicon.
3. The system of claim 1 , wherein the intermetallic includes at least one of nickel, cobalt, chromium, titanium, aluminum, copper, silver, gold, tungsten, molybdenum and iron.
4. The system of claim 1 , wherein the intermetallic includes silicon and a metal.
5. The system of claim 4 , wherein the metal includes at least one of at least one of nickel, cobalt, chromium, titanium, aluminum, copper, silver, gold, tungsten, molybdenum and iron.
6. The system of claim 1 , wherein the ion adsorbing material includes silicon coated by carbon.
7. The system of claim 1 , wherein the intermetallic is included within the nanoparticles.
8. An energy storage system comprising:
a first electrode disposed in a first region of electrolyte and including
a substrate including nanofibers,
an ion adsorbing material attached to the substrate, and
an over-layer coating the ion adsorbing material, the over-layer including a silicon oxide;
a separator configured to separate the first region and a second region of electrolyte; and
a second electrode disposed in the second region of electrolyte, the first and second electrodes and separator configured to operate as an energy storage device.
9. The system of claim 8 , wherein the ion adsorbing material includes silicon.
10. The system of claim 8 , wherein the ion adsorbing material includes nanoparticles.
11. An energy storage system comprising:
a first electrode disposed in a first region of electrolyte and including:
a substrate including nanofibers, and
an ion material attached to the substrate, the ion adsorbing material including a 3d metal oxide;
a separator configured to separate the first region and a second region of electrolyte; and
a second electrode dispersed in the second region of electrolyte, the first and second electrodes and separator configured to operate as an energy storage device.
12. The system of claim 11 , wherein the ion adsorbing material includes silicon.
13. The system of claim 11 , wherein the ion adsorbing material includes silicon coated by carbon.
14. The system of claim 13 , wherein the carbon includes a diamond like coating.
15. The system of claim 13 , wherein the ion adsorbing material includes nanoparticles.
16. The system of claim 11 , wherein the ion adsorbing material includes an aerogel.
17. An energy storage system comprising:
a first electrode disposed in a first region of electrolyte and including a substrate,
an ion adsorbing material attached to the substrate, and an over-layer coating the ion adsorbing material the over-layer including carbon;
a separator configured to separate the first region and a second region of electrolyte; and
a second electrode disposed in the second region of electrolyte, the first and second electrodes and separator configured to operate as an energy storage device.
18. The system of claim 17 , wherein the ion adsorbing material includes silicon.
19. The system of claim 17 , wherein the ion adsorbing material includes a metal oxide.
20. The system of claim 17 , wherein the ion adsorbing material includes nanoparticles.
21. The system of claim 17 , wherein the ion adsorbing material includes a metal.
22. The system of claim 17 , wherein the ion adsorbing material includes silicon and a metal.
23. The system of claim 1 , wherein the ion adsorbing material is attached to the substrate by a mesh of support filaments.
24. The system of claim 17 , wherein the ion adsorbing material is attached to the substrate by an array of vertically aligned support filaments.
25. The system of claim 1 , wherein the substrate includes support filaments and the ion adsorbing material covers less than 25% of the support filaments.
26. The system of claim 1 , further including an overlayer on the ion adsorbing material, the overlayer including SiO 2 .
27. The system of claim 1 , wherein the ion adsorbing material includes particles of ion adsorbing material.
28. The system of claim 1 , further comprising a plurality of surface effect dominant sites configured to catalyze intercalation of the charge carriers into the ion adsorbing material, the surface effect dominant cites being disposed on the nanoparticles.
29. The system of claim 1 further comprising a binder, wherein the support filaments are indirectly attached to the substrate by the binder.
30. The system of claim 1 , wherein the nanoparticles include transition metal oxide particles.
31. The system of claim 8 , wherein the ion adsorbing material includes an intermetallic and silicon.
32. The system of claim 11 , wherein the ion adsorbing material further includes an intermetallic.
33. The system of claim 23 , wherein the ion adsorbing material includes silicon and an intermetallic.
34. The system of claim 1 , wherein the nanoparticles include TiO 2 particles.
35. The system of claim 1 , wherein the nanoparticles are less than 34 nanometers in diameter.
36. The system of claim 1 , wherein the nanoparticles include transition metal oxide particles.