COMPOSITES OF POROUS NANO-FEATURED SILICON MATERIALS AND CARBON MATERIALS
Composites of porous nano-featured silicon and various materials, such as carbon, are provided. The composites find utility in various applications, such as electrical energy storage electrodes and devices comprising the same.
1 - 36 . (canceled)
37 . A composite material comprising carbon and nano-featured porous silicon, wherein the nano-featured porous silicon comprises a surface area of 30 to 120 m 2 /g and a pore volume of 0.08 to 0.3 cm 3 /g, wherein the pore volume comprises 5 to 40% micropores, 35-70% mesopores, and 30-60% macropores.
38 . The composite material of claim 37 , wherein the nano-featured porous silicon comprises a surface area of 30 to 120 m 2 /g and a pore volume of 0.09 to 0.18 cm 3 /g, wherein the pore volume comprises 5 to 15% micropores, 45-55% mesopores, and 30-45% macropores.
39 . The composite material of claim 37 , wherein a composition of the composite material and graphite has a gravimetric capacity of greater than 500 mAh/g and less than 50% expansion when tested in a Li ion half cell.
40 - 41 . (canceled)
42 . A composite material comprising porous nano-featured silicon and carbon, having a silicon content between 20% to 70% by weight, a specific surface area between 10 and 200 m 2 /g, a pore volume between 0.01 and 0.2 cm 3 /g, and a pore volume distribution comprising less than 30% micropores, less than 30% mesopores, and greater than 50% macropores.
43 . The composite material of claim 42 , wherein the silicon content is 20% to 40% by weight.
44 . The composite material of claim 42 , wherein the silicon content is 30% to 60% by weight.
45 . The composite material of claim 42 , wherein the specific surface area is between 20 m 2 /g and 150 m 2 /g.
46 . The composite material of claim 42 , wherein the specific surface area is between 20 m 2 /g and 80 m 2 /g.
47 . The composite material of claim 46 , wherein the pore volume is between 0.01 cm 3 /g and 0.1 cm 3 /g.
48 . The composite material of claim 46 , wherein the pore volume is between 0.01 cm 3 /g and 0.05 cm3/g.
49 . The composite material of claim 46 , wherein the pore volume distribution comprises less than 10% micropores, less than 10% mesopores, and greater than 80% macropores.
50 . The composite material of claim 49 , wherein the pore volume distribution comprises less than 10% micropores, less than 10% mesopores, and greater than 90% macropores.
51 . The composite material of claim 49 , wherein the pore volume distribution comprises less than 5% micropores, less than 5% mesopores, and greater than 90% macropores.
52 . The composite material of claim 49 , wherein the pore volume distribution is comprised of less than 5% micropores, less than 5% mesopores, and greater than 95% macropores.
53 . An electrode comprising the composite material according to claim 37 .
54 . (canceled)
55 . An energy storage device comprising the composite material according to claim 37 .
56 - 57 . (canceled)
58 . A method for producing a composite a material comprising carbon and porous nano-featured and nano-sized silicon comprising the following steps:
a) suspending particles of a silicon alloy in a liquid medium containing a dissolved acid;
b) storing the suspended particles for a period of time at sufficient temperature to allow for erosion of metal cations from the silicon alloy in to the liquid medium to yield highly friable silicon material with nano-sized features;
c) removing the liquid medium to yield dried highly friable silicon material with nano-sized features;
d) particle size reduction of the friable silicon material with nano-sized features to yield nano-sized silicon particles with nano-sized features;
e) blending a mixture of polymer precursors with the nano-sized silicon particles with nano-sized features;
f) storing the mixture of polymer precursors and the nano-sized silicon particles with nano-sized features for a period of time at sufficient temperature to allow for impregnation and polymerization of the polymer precursors within the nano-sized silicon particles with nano-sized features to yield polymer-impregnated nano-sized silicon particles with nano-sized features; and
g) carbonization of the polymer-impregnated silicon particles to yield a composite silicon-carbon material, wherein the silicon material is a nano-sized silicon material with nano-sized features.
59 - 73 . (canceled)
74 . An electrode comprising the composite material according to claim 42 .
75 . An energy storage device comprising the composite material according to claim 42 .