Advanced lithium-ion energy storage device
A lithium ion capacitor includes binder free positive and negative electrode active layers. The capacitor exhibits high energy density, power density and cycle life and provides a good compromise in performance between an electric double layer capacitor and a lithium ion battery.
1 . A lithium ion capacitor apparatus, comprising:
a positive electrode comprising a network of carbon that is substantially free of binder material;
a negative electrode comprising a network of carbon that is substantially free of binder material separated from the positive electrode by a separator;
an organic solvent electrolytic solution with lithium salt as an electrolyte, comprising lithium bis(fluorosulfonyl) imide in ethylene carbonate, ethylene glycol monobutyl ether, diethyl carbonate and propylene carbonate; and
a film of lithium comprising holes and disposed on the negative electrode to provide for pre-lithiation of the capacitor;
wherein at least one of the positive electrode and the negative electrode comprises:
a network of high aspect ratio carbon elements defining void spaces within the network; and
a plurality of electrode active material particles disposed in the void spaces within the network and enmeshed in the network.
2 . The apparatus of claim 1 , wherein the high aspect ratio carbon elements comprise elements each having two major dimensions and one minor dimension, wherein the ratio of the length of each of the major dimensions is at least 10 times that of the minor dimension.
3 . The apparatus of claim 1 , wherein the high aspect ratio carbon elements comprise elements each having two major dimensions and one minor dimension, wherein the ratio of the length of each of the major dimensions is at least 100 times that of the minor dimension.
4 . The apparatus of claim 1 , wherein the high aspect ratio carbon elements comprise elements each having two major dimensions and one minor dimension, wherein the ratio of the length of each of the major dimensions is at least 1,000 times that of the minor dimension.
5 . The apparatus of claim 1 , wherein the high aspect ratio carbon elements comprise elements each having two major dimensions and one minor dimension, wherein the ratio of the length of each of the major dimensions is at least 10,0000 times that of the minor dimension.
6 . The apparatus of claim 1 , wherein the high aspect ratio carbon elements comprise elements each having one major dimension and two minor dimension, wherein the ratio of the length of each the major dimension is at least 10 times that of each of the minor dimensions.
7 . The apparatus of claim 1 , wherein the high aspect ratio carbon elements comprise elements each having one major dimension and two minor dimension, wherein the ratio of the length of each the major dimension is at least 100 times that of each of the minor dimensions.
8 . The apparatus of claim 1 , wherein the high aspect ratio carbon elements comprise elements each having one major dimension and two minor dimension, wherein the ratio of the length of each the major dimension is at least 1,000 times that of each of the minor dimensions.
9 . The apparatus of claim 1 , wherein the high aspect ratio carbon elements comprise elements each having one major dimension and two minor dimension, wherein the ratio of the length of each the major dimension is at least 10,000 times that of each of the minor dimensions.
10 . The apparatus of claim 1 , wherein the high aspect ratio carbon elements comprise carbon nanotubes or carbon nanotube bundles.
11 . The apparatus of claim 1 , wherein the high aspect ratio carbon elements comprise graphene flakes.
12 . The apparatus of claim 1 , wherein the electrode active layer contains less than 10% by weight polymeric binders disposed in the void spaces.
13 . The apparatus of claim 1 , wherein the electrode active layer contains less than 1% by weight polymeric binders disposed in the void spaces.
14 . The apparatus of claim 1 , wherein the electrode active layer is substantially free of polymeric material other than the surface treatment.
15 . The apparatus of claim 1 , wherein the electrode active layer is substantially free of polymeric material.
16 . The apparatus of claim 1 , wherein the network is at least 90% carbon by weight.
17 . The apparatus of claim 1 , wherein the network is at least 95% carbon by weight.
18 . The apparatus of claim 1 , wherein the network is at least 99% carbon by weight.
19 . The apparatus of claim 1 , wherein the network is at least 99.9% carbon by weight.
20 . The apparatus of claim 1 , wherein the network comprises an electrically interconnected network of carbon elements exhibiting connectivity above a percolation threshold.
21 . The apparatus of claim 1 , wherein the network defines one or more highly electrically conductive pathways.
22 . The apparatus of claim 21 , wherein said the pathways have comprising a length greater than 100 μm.
23 . The apparatus of claim 21 , wherein said the pathways have comprising a length greater than 1,000 μm.
24 . The apparatus of claim 21 , wherein said the pathways have comprising a length greater than 10,000 μm.
25 . The apparatus of claim 1 , wherein the network includes one or more structures formed of the carbon elements, said structure comprising an overall length at least ten times the length of a largest dimension the carbon elements.
26 . The apparatus of claim 1 , wherein the network includes one or more structures formed of the carbon elements, said structure comprising an overall length at least 100 times the length of a largest dimension the carbon elements.
27 . The apparatus of claim 1 , wherein the network includes one or more structures formed of the carbon elements, said structure comprising an overall length at least 1,000 times the length of a largest dimension the carbon elements.
28 . The apparatus of claim 1 , wherein the positive electrode comprises electrode active material comprising at least one from the list consisting of: activated carbon, carbon black, graphite, hard carbon, soft carbon, nanoform carbon, high aspect ratio carbon, and mixtures thereof.
29 . The apparatus of claim 1 , wherein the positive electrode comprises electrode active material comprising activated carbon (AC) having a specific surface area in a range from 1000 to 3000 m2/g.
30 . The apparatus of claim 1 , wherein the positive electrode comprises electrode active material comprising activated carbon (AC) having a particle size D50≤10 μm.
31 . The apparatus of claim 1 , wherein the negative electrode comprises electrode active material having a particle size D50≤10 μm.
32 . The apparatus of claim 1 , wherein the positive electrode comprises electrode active material comprising activated carbon (AC), carbon black (BC) and high aspect ratio carbon, wherein the mass ratio between the active material and the high aspect ratio carbon is in the range of from 80:20 to 99:1.
33 . The apparatus of claim 1 , wherein the total combined thickness of the positive electrode and the film of lithium is in the range of 40 μm to 450 μm.
34 . The apparatus of claim 1 , wherein the total thickness of the negative electrode, is in the range of 20 μm to 350 μm.
35 . The apparatus of claim 1 , wherein the thickness ratio of the total thickness of the positive electrode active layer to the total thickness of the negative electrode active layer is in the range of 1:2 to 3:1.
36 . The apparatus of claim 1 , wherein the capacity ratio of the positive electrode active layers to the negative electrode active layers is in the range of 1:12 to 1:2.
37 . The apparatus of claim 1 , wherein the lithium film comprises an ultra thin lithium film.
38 . The apparatus of claim 1 , wherein the mass per unit area of the Li sources on a side of the negative active layer is in the range of 0.1 mg/cm 2 to 3 mg/cm 2 .
39 . The apparatus of claim 1 , wherein the thickness of the Li sources on a side of the negative active electrode layer is in the range of 2 to 50 μm.
40 . The apparatus of claim 1 , wherein the surface area of the lithium film is about 25% to about 100% of the surface area of a side of the negative electrode.
41 . The apparatus of claim 1 , wherein the area size percentage range of said holes is in the range of about 0.01% to about 75% of the total area of the film.
42 . The apparatus of claim 1 , wherein mass loading for the film of lithium comprising holes disposed on the negative electrode is less than 10% of the negative electrode active layer weight.
43 . A method for fabrication of a lithium ion capacitor, comprising:
providing an energy storage cell by
selecting a positive electrode comprising a network of carbon that is substantially free of binder material;
selecting a negative electrode comprising a network of carbon that is substantially free of binder material separated from the positive electrode by a separator;
selecting an organic solvent electrolyte solution with lithium salt as an electrolyte, comprising lithium bis(fluorosulfonyl) imide in ethylene carbonate, ethylene glycol monobutyl ether, diethyl carbonate and propylene carbonate;
disposing a film of lithium comprising holes on the negative electrode to provide for pre-lithiation of the capacitor; and
sealing the energy storage cell and electrolyte in a housing to provide the capacitor.
44 . The method of claim 43 , wherein the lithium ion capacitor comprises the apparatus of claim 41 .
45 . The method of claim 43 , wherein mass loading for the film of lithium comprising holes disposed on the negative electrode is less than 10% of the negative electrode active layer weight.