Nanoporous carbon structures for electrochemical devices
Nanoporous carbon-based scaffolds or structures, and specifically carbon aerogels and their manufacture and use thereof. Embodiments include a sulfur-doped cathode material within a lithium-sulfur battery, where the cathode is collector-less and is formed of a binder-free, monolithic, polyimide-derived carbon aerogel. The carbon aerogel includes pores that surround elemental sulfur and accommodate expansion of the sulfur during conversion to lithium sulfide. The cathode and underlying carbon aerogel provide optimal properties for use within the lithium-sulfur battery.
1. A nanoporous carbon material comprising:
a plurality of interconnected carbonized struts having a strut width of from 2 nm to 10 nm;
a plurality of pores defined by the plurality of interconnected carbonized struts, wherein:
the plurality of pores is characterized by a pore size distribution, the pore size distribution having a full width at half max of from 5 nm to 50 nm; and
the plurality of pores is characterized by a pore size of 70 nm or less at a maximum peak of the pore size distribution.
2. The nanoporous carbon material of claim 1 , wherein the pore size is 50 nm or less at the maximum peak of the pore size distribution.
3. The nanoporous carbon material of claim 1 , wherein the pore size is from 2 nm to 50 nm at the maximum peak of the pore size distribution.
4. The nanoporous carbon material of claim 1 , wherein the plurality of pores of the plurality of pores have a pore size from 2 nm to 40 nm.
5. The nanoporous carbon material of claim 1 , further characterized by a Young modulus of at least about 0.2 GPa.
6. The nanoporous carbon material of claim 1 , further characterized by a Young modulus of at least about 0.2 GPa.
7. The nanoporous carbon material of claim 1 , comprising an electrochemically active material, wherein the electrochemically active material is disposed within a pore of the plurality of pores.
8. The nanoporous carbon material of claim 7 , wherein the electrochemically active material comprises one or more particles.
9. The nanoporous carbon material of claim 7 , wherein the electrochemically active material comprises a conformal coating on a carbon surface of an interior of the pore.
10. The nanoporous carbon material of claim 7 , wherein the electrochemically active material comprises iron phosphate.
11. The nanoporous carbon material of claim 7 , wherein the electrochemically active material comprises sulfur.
12. The nanoporous carbon material of claim 11 , wherein the sulfur comprises a content of from 25 weight % to 75 weight % of the nanoporous carbon material.
13. The nanoporous carbon material of claim 11 , wherein the sulfur comprises from 1.5 milligrams (mg)/square centimeter (cm 2 ) to 2.5 mg/cm 2 .
14. The nanoporous carbon material of claim 1 , characterized by an electrical conductivity of at least 1 Siemens/centimeter.
15. The nanoporous carbon material of claim 1 , wherein the nanoporous carbon material is a binder-free monolith.
16. The nanoporous carbon material of claim 1 , wherein the nanoporous carbon material is in a powder form.
17. A battery comprising the nanoporous carbon material of claim 1 .
18. The battery of claim 17 , wherein the battery has an electrical capacity of at least 800 milliAmpere hours/gram (mAh/g).
19. The battery of claim 17 , wherein the battery has a cycle life of at least 200 cycles.
20. The battery of claim 17 , further comprising an anode that includes lithium metal.
21. The battery of claim 17 , further comprising an anode that includes silicon.