CN116368655A - Advanced lithium ion energy storage device - Google Patents

Abstract

The lithium ion capacitor includes positive and negative electrode active layers without a binder. The capacitor exhibits high energy density, power density and cycle life and provides a good performance tradeoff between an electric double layer capacitor and a lithium ion battery.

Description

Advanced lithium ion energy storage device

Cross Reference to Related Applications

The present application relates to U.S. provisional patent application No. 63/093441 entitled "Advanced Lithium ion energy storage device (Advanced Lithium-Ion Energy Storage Device)" filed on 10/19/2020, U.S. provisional patent application No. 63/021492 entitled "wide temperature electrolyte (Wide Temperature Electrolyte)" filed on 5/8/2020; us patent 10,600,582 entitled "composite electrode (Composite Electrode)" issued on month 3 and 24 of 2020; U.S. patent No. 9,001,495 entitled "high power and high energy electrode using carbon nanotubes (High power and high energy electrodes using carbon nanotubes)" issued on month 7 of 2015, and U.S. patent No. 9,218,917 entitled "energy storage medium for ultracapacitor (Energy storage media for ultracapacitors)" issued on month 22 of 2015, the entire disclosures of which are incorporated herein by reference for any purposes.

Background

1. Field of the invention

The invention disclosed herein relates to energy storage devices, and in particular, to lithium-containing electrodes that are fabricated substantially without the use of binder materials.

2. Description of related Art

Lithium (Li) ion batteries (LiB) and Electric Double Layer Capacitors (EDLC) are two widely used electrochemical energy storage devices. Typical libs are made of lithium (Li) intercalated anodes and lithium metal oxide cathodes (thus, the reduction process or faraday mechanism of energy storage), while EDLCs are made of high surface area Activated Carbon (AC) for both the anode and cathode (thus, relying on double layer capacitance or energy storage in non-faraday form). The energy and power performance of these devices varies due to their different energy storage mechanisms. LiB exhibits a high specific energy, for example 100-250Wh/kg; however, liB also has a low specific power of <0.5kW/kg and a poor cycle life of <5,000 cycles. EDLC has a high specific power of 10kW/kg and a long cycle life exceeding 100,000 cycles; however, EDLC exhibits a much lower specific energy of less than 6 Wh/kg.

Energy storage devices that are capable of combining the advantages of LiB and EDLC in a single form are highly desirable. As a new generation of supercapacitors, lithium ion capacitors (lics) are an advanced energy storage device that contains an EDLC cathode and a prelithiated anode, with ions shuttling between them during charging and discharging. Due to the use of pre-lithiated and low surface anode materials, the LiC can be charged to voltages up to 4.0V, which is much higher than EDLC and comparable to LiB. While LiC can achieve much higher power densities than LiB, liC has an energy density of about 10-20Wh/kg, still much lower than LiB. Therefore, there is a need for further improvements in the energy density of lics energy storage devices.

There is a need for methods and apparatus that improve the prospects of lics technology. Preferably, the method and apparatus also reduce the cost and time required for manufacturing.

Disclosure of Invention

In one embodiment, a lithium ion capacitor device is provided. The apparatus comprises: a positive electrode comprising a carbon network substantially free of binder material; a negative electrode comprising a carbon network substantially free of binder material, the negative electrode being separated from the positive electrode by a separator; and a lithium film disposed on the negative electrode to provide 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; a plurality of electrode active material particles disposed in void spaces within the network and embedded in the network.

In some embodiments, the high aspect ratio carbon element comprises elements each having two major dimensions and one minor dimension, wherein the length ratio of each major dimension is at least 10 times the length ratio of the minor dimension. The high aspect ratio carbon element may comprise elements each having two major dimensions and one minor dimension, wherein the length ratio of each major dimension is at least 100 times the length ratio of the minor dimension. The high aspect ratio carbon element may comprise elements each having two major dimensions and one minor dimension, wherein the length ratio of each major dimension is at least 1,000 times the length ratio of the minor dimension. The high aspect ratio carbon element may comprise elements each having two major dimensions and one minor dimension, wherein the length ratio of each major dimension is at least 10,0000 times the length ratio of the minor dimension. High aspect ratio The specific carbon element may comprise elements each having a major dimension and two minor dimensions, wherein the length ratio of each major dimension is at least 10 times the length ratio of each minor dimension. The high aspect ratio carbon element may comprise elements each having a major dimension and two minor dimensions, wherein the length ratio of each major dimension is at least 100 times the length ratio of each minor dimension. The high aspect ratio carbon element may comprise elements each having a major dimension and two minor dimensions, wherein the length ratio of each major dimension is at least 1,000 times the length ratio of each minor dimension. The high aspect ratio carbon element may comprise elements each having a major dimension and two minor dimensions, wherein the length ratio of each major dimension is at least 10,000 times the length ratio of each minor dimension. The high aspect ratio carbon element may comprise carbon nanotubes or bundles of carbon nanotubes. The high aspect ratio carbon element may comprise graphene flakes. The electrode active layer may contain less than 10 wt% polymeric binder disposed in the void space. The electrode active layer may contain less than 1 wt% polymeric binder disposed in the void space. The electrode active layer may contain less than 1 wt% polymeric binder disposed in the void space. The electrode active layer may be substantially free of polymeric materials other than surface treatment. The electrode active layer may be substantially free of polymeric material. The network may be at least 90 wt% carbon. The network may be at least 95 wt% carbon. The network may be at least 99 wt% carbon. The network may be at least 99.9 wt% carbon. The network may comprise an electrically interconnected network of carbon elements exhibiting connectivity above a percolation threshold. The network may define one or more highly conductive paths. The path may have a length greater than 100 μm. The path may have a length greater than 1,000 μm. The path may have a length greater than 10,000 μm. The network may comprise one or more structures formed of carbon elements, the structures comprising a total length of at least ten times the length of the largest dimension of the carbon elements. The network may comprise one or more structures formed of carbon elements, the structures comprising a total length of at least 100 times the length of the largest dimension of the carbon elements. The network may comprise one or more structures formed from elemental carbon comprising A total length of at least 1,000 times the length of the largest dimension of the carbon element. The positive electrode may contain an electrode active material containing at least one of the list consisting of: activated carbon, carbon black, graphite, hard carbon, soft carbon, nano-form carbon, high aspect ratio carbon, and mixtures thereof. The positive electrode may comprise a material having a specific surface area of 1000 to 3000m ² An electrode active material of Activated Carbon (AC) in the range of/g. The positive electrode may contain an electrode active material of Activated Carbon (AC) having a particle size D50.ltoreq.10 μm. The negative electrode may contain an electrode active material having a particle size d50.ltoreq.10 μm. The positive electrode may include an electrode active material having Activated Carbon (AC), carbon Black (BC), and high aspect ratio carbon, wherein a mass ratio between the active material and the high aspect ratio carbon is in a range of 80:20 to 99:1. The total combined thickness of the positive electrode and the lithium film may be in the range of 40 μm to 450 μm. The total thickness of the negative electrode may be in the range of 20 μm to 350 μm. The thickness ratio of the total thickness of the positive electrode active layer to the total thickness of the negative electrode active layer may be in the range of 1:2 to 3:1. The capacity ratio of the positive electrode active layer to the negative electrode active layer is in the range of 1:12 to 1:2. The lithium film may comprise an ultra-thin lithium film comprising pores. The mass per unit area of the lithium source on one side of the anode active layer may be 0.1mg/cm ² To 3mg/cm ² Within a range of (2). The thickness of the lithium source on one side of the negative electrode active layer may be in the range of 2 to 50 μm. The surface area of the lithium film may be about 25% to about 100% of the surface area of the side of the negative electrode. The lithium film may comprise pores, and wherein the area size percentage of the pores ranges from about 0.01% to about 75% of the total area of the film.

In another embodiment, a method for manufacturing a lithium ion capacitor is provided. The method comprises providing an energy storage cell by selecting a positive electrode comprising a carbon network that is substantially free of binder material; selecting a negative electrode comprising a carbon network substantially free of binder material, the negative electrode being separated from the positive electrode by a separator; disposing a lithium film on the negative electrode to provide pre-lithiation of the capacitor; the energy storage cell and electrolyte are sealed in a housing to provide a capacitor. The lithium ion capacitor may comprise the device described above.

Drawings

The features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings in which:

a series of microscopic, flow and performance charts are provided.

Detailed Description

Disclosed herein are methods and apparatus for manufacturing hybrid, binder-free electrodes useful in energy storage devices. Advantageously, the electrodes disclosed herein are capable of delivering excellent electrical performance and require fewer steps in the manufacturing process, as they are substantially free of binder materials conventionally used in electrode construction.

The energy storage devices disclosed herein combine the advantages of LiB and LiC while avoiding inherent drawbacks, thus bridging the gap between the high energy density provided by LiB and the high power density exhibited in LiC. Furthermore, the fundamental difference between such lithium ion energy storage devices and LiC is that hybrid lithium ion technology integrates two separate energy storage devices into one by synergistically bonding the LiB and LiC cathode materials together to form a hybrid composite cathode. When the battery material is charged while maintaining a constant battery reduction reaction potential, the non-faradaic capacitor material may initially be electrostatically charged until the potential of the electrode reaches the reduction reaction potential of the faradaic battery material. Once fully charged, the capacitor material is charged again until the capacitor material reaches a limiting potential.

In general, the disclosed technology relates to a hybrid lithium ion energy storage device comprising a hybrid composite binderless cathode electrode, a binderless anode electrode, a separator, and an organic solvent electrolyte having a lithium salt as an electrolyte, and an ultra-thin lithium film (μ -Li) source. The ultra-thin lithium film may include a plurality of pores. The anode electrode is pre-doped with sufficient lithium ions by means of an ultra-thin lithium film. Pre-doping may occur by placing an ultra-thin lithium film substantially on the surface of the anode electrode. In addition, the hybrid composite cathode may be manufactured using a manufacturing process without a polymer binder, and the capacity ratio of the resultant hybrid composite cathode to the anode electrode may be 0.1 to 1.2. The quality of the ultra-thin lithium film disposed on the anode electrode can be predetermined by a computational formula to achieve high energy, high power and long cycle life performance in a full cell format design.

A schematic of an energy storage device is depicted in fig. 1. In the example of fig. 1, the Energy Storage Device (ESD) 10 is a three-layer battery. The opposing current collector 2 is the body of cathode material 3. The current collector 2 and the cathode material 3 together provide each of the two cathodes 4 shown. The anode 8 is shown as being positioned between the cathodes 3. The anode 8 in this example comprises an opposite layer of anode material 5 disposed on another current collector 6. A lithium source 7 is disposed over each layer of anode material. In this example, the current collector 2 for the cathode is made of aluminum and the current collector 6 for the anode is made of copper.

Referring to fig. 2A and 2B, an example of a cathode material 3 containing activated carbon is shown. In these illustrations, SEM images of cathode material 3 in the prior art (fig. 2A) and according to the teachings herein (fig. 2B) are shown. As can be seen, the image of the cathode 4 disclosed herein contains substantially more carbon and, as can be easily speculated, can have a greater energy storage than the device of fig. 2A.

For discussion purposes, two examples of cathode materials are presented herein. A first example comprises an electrode with pure Activated Carbon (AC) (lics with 0% lithium iron phosphate (LFP); a second example includes a hybrid adhesive-free electrode (LFP to AC ratio of 20:80). In a binderless electrode, the carbon structure provided results in good bonding with the active material and serves to bond the cathode together without the need for conventional polymers or similar non-conductive or poorly conductive binders. The carbon structure results in higher conductivity and higher battery performance due to the absence of a (non-conductive) binder. In this disclosure, a commercially available dry AC adhesive-based electrode was used as a baseline for comparison.

In general, the binder material is a non-conductive or poorly conductive material added to the electrode material to promote mechanical integrity of the electrode layer and good adhesion to the current collector. The use of binder materials replaces other materials that are capable of storing energy and conducting electricity, thereby reducing the output of energy storage cells using these materials. One example of a binder is PVDF. Polyvinylidene fluoride (PVDF) is a highly non-reactive thermoplastic fluoropolymer polymerized from vinylidene fluoride. PVDF is typically used for the cathode. One common anode binder material is a styrene-butadiene copolymer.

Similarly, in fig. 3A, 3B, and 3C, the anode material 5 is shown. In fig. 3A, an SEM of hard carbon powder is presented. In fig. 3B, a prior art anode 8 made of hard carbon powder and binder material is shown. In fig. 3C, aspects of anode 8 according to the teachings herein are shown.

For discussion purposes, the anode 8 presented herein is composed of Hard Carbon (HC) as the active material. A slurry mixture for an anode was prepared and contained HC having a particle size (D50) of 2 μm and carbon nanotubes having carboxymethyl cellulose (CNT and CMC) functionality as binder materials. In this example, the mass ratio of the three components is 98.33:0.67:1. after the slurry was prepared, the slurry was coated on a copper (Cu) foil substrate having a thickness of 10 μm. The electrode was then dried in an oven with flowing air at 160 degrees celsius for three hours. Manufacture of one-sided active material layer thickness of about 75 μm and tap density of 1.0g/cm ³ Is provided. The porosity of the hard carbon anode was about 50%. The electrodes were then punched from the electrode sheet to the desired dimensions, with an anode of 4.6cm x 4.6cm (active area), and a cathode of 4.5cm x 4.5cm, then vacuum dried overnight at 120 degrees celsius and transferred to a dry room environment before final cell assembly therein. The electrodes are assembled into the configuration depicted in fig. 1.

When the ESD 10 is assembled, the lithium source 7 is incorporated for all anodes 8. In each embodiment, the lithium source 7 comprises an ultra-thin lithium film having pores therein. These holes were cut from 20 μm lithium metal sheet (99.9% purity). The lithium source 7 provides a lithium source for pre-lithiation having various dimensions to make various LiB/LiC batteries based on LFP/AC hybrid composite cathodes. The amount of u-Li with pores preloaded onto the HC anode surface to fully prelithiate HC was determined to be 10% (u-Li preloaded mass/anode active layer mass) based on the HC anode first intercalation specific capacity of about 372 mAh/g. In the cell design of LiC (0% LFP), it was determined that the anode should be pre-lithiated (with about 10% lithium loading) because the cathode to anode capacity ratio was about 0.14 (1:7). This LiC cell design gives lics with long cycles and high energy and power densities. However, when LFP is mixed in the mixed composite binderless cathode, LFP will provide an additional source of lithium from the mixed cathode when charged to the maximum operating voltage. In order to avoid lithium dendrite growth in the anode during battery charging, the actual mass loading of the lithium source 7 (i.e. the ultra thin lithium film with pores) placed on the anode surface should take into account the fraction of the lithium source provided by LFP in the hybrid cathode and thus should be less than 10% of the weight of the anode active layer. It can be concluded that the decrease of the lithium source 7 at the anode should be related to the increase of LFP in the cathode.

During battery assembly, loading of the lithium source 7 is performed in a dry room environment. An ultra-thin lithium film is placed under applied pressure. In the example of an assembled ESD 10, the scheme shown in fig. 1 is followed. The anode is a double sided HC anode preloaded with a lithium source with holes and between two single sided LFP/AC composite cathodes. The electrolyte used was 1MLiPF6, a 1:1 mixture of Ethylene Carbonate (EC) and dimethyl carbonate (DMC) by weight. All pouch cell assemblies were performed in a dry room environment (-40 ℃ dew point). Fig. 4 depicts charge/discharge distributions collected during an initial test.

Fig. 4 shows initial test results of lics with binder-free AC and HC electrodes at different current charges and discharges. The test conditions for these examples included: cathode porosity of 83.1%; anode porosity of 64.1%. The voltage range of the battery is 3.8-2.2V; the capacitance is 11.2F; ESR is 0.127 ohms and RC constant is 1.4 seconds. Specific energy and energy density based on the weight and volume of the cathode and anode active layers were determined to be 36.6Wh/kg and 20.1Wh/L, respectively. The maximum specific power and power density based on the weight and volume of the cathode and anode active layers were determined to be 69.7kW/kg and 35.3kW/L, respectively.

From the results, it is estimated that the specific energy and energy density of full-sized multi-layer 1000F LiC pouch cells can be 9Wh/kg and 16Wh/L for this cell design, which is substantially higher than the competitive 1000F LiC energy density (13.7 Wh/L). In addition, it is estimated that for this cell design, the ESR of a soft pack cell with full-sized multi-layer 1000F LIC can be 1.4 milliohms, which is less than the ESR of a competitive 1000F LIC cell (1.6 milliohms). Table 1 below provides a more detailed comparison with the prior art.

TABLE 1

As can be seen from the comparison in table 1, the ESR based on the binderless electrode LiC was 30.6% less than the control sample based on the binder (i.e., prior art). Similarly, the RC constant of lics with binderless electrodes is only 1.4 seconds, while binder-based lics have an RC constant of 5.1 seconds. The maximum specific power and power density based on lics without binder electrodes were 131.6% and 64.6% higher, respectively, than the binder (i.e., prior art) based control samples. Fig. 5A depicts a comparison ESR, where fig. 5B is an exploded view of the curve presented in fig. 5A. Aspects of the second embodiment of the test are introduced in fig. 6A, 6B, 7A and 7B.

In a second example, the comparative performance was studied using soft carbon and electrodes without AC and LFP binders. The ratio of SC: CNT: CMC was the same as the HC slurry, and this time 20% LFP was added to the carbon framework with Activated Carbon (AC) to achieve a hybrid composite electrode. Fig. 6A and 6B are photomicrographs of soft carbon-based electrodes. Fig. 7A and 7B are microscopic images of electrodes without AC and LFP binders. The assembly of the battery follows the same procedure as the first embodiment described above. The physical aspects of the battery are set forth in table 2.

TABLE 2

In table 2, control cells (i.e., prior art soft carbon) are identified as a53 and a21. The batteries manufactured without adhesive were identified as B43 and B44. The electrolyte used in the battery is: a53: 1.0M LiPF in EC/DMC+1% VC ₆ The method comprises the steps of carrying out a first treatment on the surface of the A21: 1.0M LiPF in EC/EMC/MB (20:20:60 by volume) ₆ +0.1MLiDFOB；B43：EC/EMC/DEC/PC(1.0M LiFSI+1% VC in 20:46.7:23.3:10) by volume; and B44: 1.0M LiFSI+1% VC in EC/EB/DEC/PC (20:46.7:23.3:10 by volume). Initial charge-discharge curves of the secondary batteries were 0.25 and 12.5mA/cm2 (10 and 500 mA). Fig. 8 depicts the charge/discharge performance of four batteries. This involves an initial constant current charge-discharge and ESR results.

Fig. 9 depicts the results of the low temperature test. Because a53 cannot operate at-45 degrees celsius, a53 is not included in the charge-discharge test. In the test, a21 showed the highest capacity retention at-45 degrees celsius: about 40%. B44 shows the second highest capacity retention at-45 degrees celsius: about 30%. Based on the cell design, the specific energy of the LIC is about 22.4Wh/kg, and the 30% retention would be 6.7Wh/kg, which still maintains half of the original design 13 Wh/kg. LFP additives appear to reduce the capacity retention of the low temperature test. Fig. 10 provides comparative performance for soft carbon and hard carbon anodes. As can be seen in fig. 10, B44 shows the best impedance compared to the other two electrolytes. For EIS, the performance of the hard carbon anode is slightly better than the soft carbon anode for LIC, as shown by the smaller semicircle in the graph.

The third embodiment relates to optimizing electrolyte formulations at high and low temperatures. In this example, Y4 is an electrolyte control sample: 1.0M LiTFSI, EC/EMC/MB (20:20:60 by volume) +1% VC. Y5 and Y5.1 are BCN solvent based electrolytes with LiTFSI salts and additives, containing VC, FEC, liDFOB, liBOB, liDFOP, liNO ₃ . The electrolyte formulation for Y5 is: 1.0M LiTFSI in BCN/EC/VC (80/10/10 by volume); the Y5.1 electrolyte formulation is: 1.0M LiTFSI+1% OS in BCN/EC/VC (80/10/10 by volume) ₃ A commercially available additive.

Fig. 11 is a graph depicting ESR performance of three different types of electrolytes as a function of temperature. At a low temperature of-40 degrees celsius, the ESR of the adhesive-free LIC was found to increase by 3.4 ohms, whereas the ESR of the conventional adhesive-based LIC increased by 5.1 ohms. Using the Y5 electrolyte, the cell also passed the long-term cycle life test and the results can be seen in fig. 12. In FIG. 12, a room temperature high C rate cycle life test for LIC with electrolyte Y5; the voltage range is 3.8-2.2V and the current is about 500mA.

In a fourth example, the performance of both high temperature (85 degrees celsius) and low temperature (-55 degrees celsius) electrolyte formulations was evaluated. Partitioning Y7 to a BCN solvent based electrolyte with LiTFSI salt with co-solvent comprising GBL (gamma-butyrolactone), VC, FEC and containing LiDFOB, liBOB, liDFOP, liNO ₃ And the like. The Y7 electrolyte formulation is: BCN/GBL/VC/OS ₃ (74.5/12.5/10/3 by volume) LiTFSI. Fig. 13 to 15 depict the high temperature cycling and direct charging results of LIC with Y7 electrolyte. Y7 has the same-55 ℃ low temperature performance as Y5 and Y5.1. Fig. 13 depicts a cycle life performance graph of a battery with Y7 electrolyte charged-discharged from 3.8V-2.2V at a constant current of 500mA, a capacitance/ESR retention as a function of cycle number, and a cycling environment of 85 degrees celsius. Fig. 14 presents discharge curves at various cycle times when LIC cycling was performed at 85 degrees celsius based on Y7 electrolyte. Fig. 15 shows a comparison of discharge curves after a constant voltage was maintained at 3.8V (float test) at 85 degrees celsius before and after 330 h.

A method of manufacturing a battery according to the teachings herein is provided in fig. 16.

In some embodiments, the positive electrode used is an electrode comprising a sheet-shaped metal current collector having a conductive material coated on both sides and electrode layers composed of a positive electrode active material and CNTs and formed on both surfaces of the current collector. The negative electrode used in this LIC laminate battery is an electrode comprising a sheet-shaped metal current collector having a conductive material coated on both sides and electrode layers composed of a negative electrode active material and additives and formed on both surfaces of the current collector.

The current collector used in the positive electrode may be made of aluminum, stainless steel, or other materials. In some examples presented, aluminum is used. The current collector used in the negative electrode may be composed of stainless steel, copper, nickel, or the like. In some examples presented, copper is used. In general, the thickness of the current collectors in the positive and negative electrodes is in the range of about 5 to 50 μm. In the example presented, the range is between 8 and 25 μm. This range allows the obtained positive and negative electrodes to have high strength and to be easily coated with the conductive coating material slurry. The coating precision of the conductive material and the volumetric energy density and gravimetric specific energy density can be improved. Both surfaces of the positive current collector and the negative current collector were coated with a carbon conductive coating slurry by a spray/coating method and dried, thereby obtaining a current collector having conductive layers for both positive and negative electrodes. The carbon conductive coating thickness on one side of the current collector is 1 to 20 μm. In the example presented, the thickness is in the range between 3 and 12 μm.

The positive electrode and the negative electrode may be made of the above electrode active materials. Specifically, the positive/negative electrode active material powder, CNT, and some solvent are dispersed into a blender/mixer to be mixed to obtain a wet slurry mixture. The percentage of additive added to the powder/slurry mixture is preferably 2% to 12%. For positive electrode fabrication, the slurry can be fabricated without a binder. The slurry mixture is then coated onto a substrate as a positive electrode active material layer. The thickness of the positive electrode active layer is 30 to 250 μm, or in some embodiments, 50 to 200 μm. The binderless electrode is then calendered by hot nip rolls at high temperature to form the final positive electrode of the LIC cell having the desired porosity and compression density. The positive electrode active material, additives, and deionized water/IPA as solvent are first mixed in a mixer for a sufficient time to form a uniform wet slurry. Then, the slurry was coated on both sides of the carbon conductive pre-coated current collector by attaching an electrode coater having a drying furnace, so that the coated electrode could be dried. The gap of the coater can be adjusted according to the initial thickness requirements of the electrode fabrication. The dried electrode was then pressed down to the desired active layer thickness by hot press calendaring to form the final positive electrode for the LIC cell. The thickness of the positive electrode active layer on one side of the current collector based on the wet slurry manufacturing method is 3 to 250 μm, and in some embodiments, 5 to 200 μm.

The negative electrode active material, CNT/CMC additive, and deionized water as a solvent are first mixed in a mixer for a sufficient time to form a uniform wet slurry. Then, the slurry was coated on both sides of the carbon conductive pre-coated current collector by attaching an electrode coater having a drying furnace, so that the coated electrode could be dried. The gap of the coater can be adjusted according to the initial thickness requirements of the electrode fabrication. The dried electrode is then pressed down to the desired active layer thickness by hot press calendaring to form the final negative electrode for the LIC cell. The thickness of the negative electrode active layer on one side of the current collector based on the wet slurry manufacturing method is 3 to 200 μm, and 5 to 160 μm is used in some embodiments.

In some embodiments of the LiC cells presented herein, the total thickness of the positive electrode can be 40 μm to 450 μm, including the thickness of the double-sided conductive material pre-coated current collector and the thickness of the double-sided active layer. In some embodiments of the LiC cells presented herein, the total thickness of the negative electrode may be 20 μm to 350 μm, including the thickness of the double-sided conductive material pre-coated current collector and the thickness of the double-sided active material layer. In some embodiments of the LiC cells presented herein, the thickness ratio of the total thickness of the positive electrode active layer to the total thickness of the negative electrode active layer may be 1:2 to 3:1.

In general, the positive electrode used is an electrode comprising a sheet-shaped metal current collector having a conductive material coated on both sides and electrode layers composed of a positive electrode active material and CNTs and formed on both surfaces of the current collector. The negative electrode used in the LIC laminated battery of the present invention is an electrode comprising a sheet-shaped metal current collector having a conductive material coated on both sides and electrode layers composed of a negative electrode active material and an additive and formed on both surfaces of the current collector.

Generally, the lithium source preloaded on the surface of the negative electrode is an ultra-thin lithium film having pores. The ultra-thin lithium film with holes is applied to the surface of all prefabricated negative electrodes by a manufacturing process of laminating the negative electrodes with top and bottom ultra-thin lithium films with holes, which is described in detail in U.S. patent application US 15/489,813, which is incorporated herein by reference in its entirety. The manufacturing may be performed in a drying chamber having a dew point below-45 ℃. The pressure of the laminating roller may be 40kg/cm ² To 400kg/cm ² . In some embodiments of the LiC cells presented herein, the devices areThe ultra-thin lithium film having holes carried on one side surface of the negative electrode preferably has a mass per unit area of 0.1mg/cm ² To 3mg/cm ² . The thickness of the ultra-thin lithium film having a hole preloaded onto one side surface of the negative electrode is preferably 2 to 50 μm. The length of the ultra-thin lithium film having holes as the lithium source loaded onto the surface of the negative electrode may be 30mm to 250mm, and the width of the ultra-thin lithium film having holes as the lithium source loaded onto the surface of the negative electrode may be 30mm to 150mm. The area of the ultra-thin lithium film having holes as a lithium source loaded onto the surface of the negative electrode may be about 25% to about 100% of the area of the negative electrode. The area size percentage of the pores in the ultra-thin lithium film having pores as a lithium source loaded onto the negative electrode surface may range from about 0.01% to about 75%. The mass ratio of the ultra-thin lithium film having holes preloaded onto both side surfaces of the negative electrode to the two side negative electrode active layers is preferably 7% to 14%. After all the ultrathin lithium film with holes is pressed onto the negative electrode, there may be a uniform thin layer lithium source location distribution on the surface of the negative electrode.

In some embodiments of the lics cells presented herein, electrodes comprising positive and negative electrodes, which are surface preloaded with a lithium source, are stamped to a specified size with some additional current collector tabs prior to stacking into a cell unit. The size of the electrodes determines the final size of the LIC cell, as the outer container should be matched to the size of the electrodes. In some embodiments, the length and width of the negative electrode is 0.5mm to 5mm greater than the length and width of the positive electrode for a LiC cell. In some embodiments of the lics cells presented herein, the length of the stamped positive and negative electrodes can be 30mm to 250mm, and the width of the stamped positive and negative electrodes can be 30mm to 150mm.

Having described aspects of lithium ion capacitors, additional features and embodiments are now described.

In lics, activated carbon may be used as a Positive Electrode (PE), while a Negative Electrode (NE) material may comprise various materials, such as soft carbon, hard carbon, graphite, and the like.

The cell composition and design can be modified to improve the electrochemical performance of the LiC. This may include active materials and CNTs considered for PE, NE active materials and CNTs, thickness/mass ratio of PE to NE active layer (current collector without aluminum (Al) and copper (Cu)) and capacity ratio of PE to NE active layer. Sizing and layer number of PE and NE, type of separator material, electrolyte composition and pre-lithiation method of NE. For PE, the active material may be Activated Carbon (AC) without a binder. For NEs, the active materials may be Hard Carbon (HC), soft Carbon (SC), graphite (G), and other carbon-based materials, and may rely on networks of CNTs and CMC to create a strong carbon structure for the active material. The material of the separator may be polypropylene (PP), polyethylene (PE), and cellulose or other similar materials.

In some embodiments of the LiC cells presented herein, the cell units are formed by stacking positive and negative electrodes through separators in an outer container (e.g., a laminated outer container). The negative electrode is pre-doped by pressing a lithium source comprising an ultra-thin lithium film with holes on the surface of the negative electrode. "pre-doping" generally refers to the phenomenon in which lithium ions enter the negative electrode active layer. An ultra-thin lithium film with holes is a lithium ion supply source for pre-doping the negative electrode. The lithium source loading process may ensure that the negative electrode contains uniform lithium on the surface so that the negative electrode may be smoothly and uniformly pre-doped with lithium ions when filled with electrolyte.

In some embodiments of the LiC cells presented herein, cu and Al substrates are welded to nickel (Ni) coated copper (Cu) and aluminum (Al) current collector tabs, respectively. After the stacking and welding process, the electrode units are accommodated in a container, e.g. an aluminum laminate molded case, which is adapted to the size of the electrode units, and a three-sided heat sealing process will be applied. Then, a required amount of electrolyte is filled into the LIC laminate cell to soak the cell to initiate the pre-doping process by intercalation of lithium into the negative electrode. After the cell has been immersed for a sufficient time, a vacuum sealing process will be applied to the cell to remove excess gases trapped in the LIC laminate cell. Accordingly, the LIC laminate battery can realize such a configuration.

The organic electrolyte may be a lithium ion battery electrolyte containing a lithium salt. To ensure that the LIC can achieve the desired electrochemical performance, prelithiation of the NE may be performed. Some prelithiation methods, including Electrochemical (EC) and External Short Circuit (ESC) methods, utilize a block of lithium metal as the sacrificial third electrode to prelithiate lithium into the graphite or HC electrode. In the EC prelithiation method, NE and Li metals are separated with a separator in a lithium-based organic electrolyte, and the predoping process may be performed by an electron charger controlling a charging current or voltage.

The positive electrode active material should be capable of reversibly adsorbing or desorbing lithium ions and anions in an electrolyte such as tetrafluoroborate. An example of such an active material is activated carbon powder. The specific surface area of the activated carbon is 1,500m ² /g to 2,800m ² /g, preferably 1,600m ² /g to 2,400m ² And/g. Preferably, the diameter (D50) (average particle diameter) of 50% of the cumulative volume of the activated carbon should be 2 μm to 10. Mu.m. Particularly preferably 3 μm to 8 μm, so that the energy density and the power density of the LIC laminate battery can be further improved. Some other examples of such materials may be carbon black and activated carbon/carbon black/CNT composites (AC/CB/CNT).

The negative electrode active material should be capable of reversibly intercalating and deintercalating with lithium ions. Examples of such active materials include graphite-based composite particles, non-graphitizable carbon (hard carbon (HC)) and graphitizable carbon (soft carbon (SC)). In some embodiments, negative electrode active materials, HC, and SC particles are preferred because they can achieve higher power performance and cycling stability than graphite materials. However, graphite materials may achieve higher energy performance for LIC because graphite has a higher specific capacity than HC and SC. In order to improve the power performance of the LIC battery, HC and SC having a diameter (D50) in the range of 1.0 to 10 μm, in some embodiments in the range of 2 to 6 μm, with a particle diameter satisfying 50% of the cumulative volume, are preferably used as the negative electrode active material.

It should be noted that it is difficult to produce HC and SC particles with a diameter (D50) of less than 10 μm for 50% of the cumulative volume. When HC and SC particles have a diameter (D50) of 50% of the cumulative volume exceeding 10 μm, it is difficult to realize an LIC battery having sufficiently small internal resistance. In some embodiments, the negative electrode active material has a thickness of 0.1 to 200m ² Specific surface area per gram, and0.6 to 60m ² Preferably/g. The reason for setting this range is that if the specific surface area of the negative electrode active material is less than 0.1m ² The resistance of the LIC battery may be high if/g, and if the specific surface area of the negative electrode active material is greater than 200m ² The irreversible capacity of the LIC laminate battery during charging can be high.

In the ESC prelithiation method, NE and the sacrificial lithium metal third electrode are shorted by an external wire connection. However, using the conventional prelithiation method, it takes time to dissipate the lithium and completely lithiate the battery to NE in the LIC laminate battery. The time required increases the cost of this method. Moreover, in conventional prelithiation methods, both the PE and NE current collectors should be porous to provide a path for lithium ions to travel from the lithium metal electrode through the LIC laminate cell, which also increases the manufacturing cost of the electrode.

Techniques for prelithiation as disclosed herein address some of these issues. That is, loading an ultrathin lithium film (abbreviated as u-Li) with pores onto the surface of NE may contribute to the battery manufacturing process and accelerate prelithiation. Because lithium metal can be coated directly on the carbon electrode, the current collector need not be porous to allow lithium ions to intercalate into the NE. After impregnating the cell with electrolyte, the Li source on the surface of the NE reacts electrochemically with the carbon electrode active layer and intercalates into the NE.

Some advantages of the techniques disclosed herein are now presented.

An advantage of the disclosed technology is a Lithium Ion Capacitor (LIC) that has excellent characteristics in terms of lifetime, including cycle lifetime and DC lifetime, while also maintaining high energy and power densities.

The disclosed technology has the advantage of having a binder-free positive electrode, a negative electrode with a lithium source pre-loaded on the surface, known as ultra-thin lithium film with pores (u-Li), a separator and an LIC of an organic solvent electrolyte with lithium salt as electrolyte.

The advantage of the disclosed technology is an LIC cell in which the positive electrode active material is preferably activated carbon, carbon black, CNT and activated carbon/carbon black/CNT mix (AC/CB/CNT) and the negative electrode active material is preferably hard carbon, soft carbon, graphite, CNT and any possible mixtures of the above.

The disclosed technology has the advantage of LIC batteries in which the positive electrode active material Activated Carbon (AC) has a dielectric constant of 1000 to 3000m ² Surface area in the range of/g.

The disclosed technology has the advantage of LIC batteries in which the positive electrode active material, activated Carbon (AC), has a particle size D50 of 10 μm or less and the negative electrode active material has a particle size D50 of 10 μm or less.

An advantage of the disclosed technology is an LIC cell in which no polymeric binder is used in the cathode material, which increases the conductivity of the electrode and improves the power performance.

An advantage of the disclosed technology is an LIC cell in which the positive electrode formulation can be adjusted over a range of mass ratios between AC/CB and CNT/carbon frames. And no or substantially no polymeric binder is used.

An advantage of the disclosed technology is an LIC cell, wherein the additives used to make the negative electrode used in such an LIC cell are preferably CNT and carboxymethyl cellulose (CMC).

An advantage of the disclosed technology is an LIC cell in which the negative electrode formulation can be tuned over a mass ratio between the negative electrode active material and CNT/CMC.

An advantage of the disclosed technology is an LIC cell in which the total thickness of the positive electrode is 40 μm to 450 μm, including the thickness of the double-sided conductive material pre-coated aluminum (Al) foil and the thickness of the double-sided active material layer.

An advantage of the disclosed technology is an LIC cell in which the total thickness of the negative electrode is 20 μm to 350 μm, which total thickness comprises the thickness of the double sided conductive material pre-coated copper (Cu) foil and the thickness of the double sided active material layer.

An advantage of the disclosed technology is an LIC cell in which the thickness ratio of the total thickness of the positive electrode active layer to the total thickness of the negative electrode active layer is preferably 1:2 to 3:1.

An advantage of the disclosed technology is an LIC cell in which the capacity ratio of the positive electrode active layer to the negative electrode active layer is preferably 1:12 to 1:2.

An advantage of the disclosed technology is an LIC battery, wherein the material of the separator is a cellulose, polypropylene (PP) and Polyethylene (PE) based material.

The disclosed technology has the advantage of an LIC battery in which the mass per unit area of a lithium source comprising an ultrathin lithium film having pores, loaded onto one side surface of a negative electrode, is preferably 0.1mg/cm ² To 3mg/cm ² 。

An advantage of the disclosed technology is an LIC cell in which the thickness of the lithium source ultra-thin lithium film with holes (u-Li) loaded onto one side surface of the negative electrode is preferably 2 to 50 μm.

An advantage of the disclosed technology is an LIC battery in which the area of the ultra-thin lithium film (u-Li) with holes as a lithium source preloaded onto one side surface of the negative electrode is about 25% to about 100% of the area of the negative electrode.

An advantage of the disclosed technology is an LIC battery in which the area percentage of the pores in the ultra-thin lithium film with pores as a lithium source preloaded onto the negative electrode surface ranges from 0.01% to about 75%.

An advantage of the disclosed technology is an LIC battery in which the mass ratio of the lithium source comprising an ultra-thin lithium film with holes preloaded onto one side surface of the negative electrode to one side negative electrode active layer is preferably 7% to 14%.

An advantage of the disclosed technology is an LIC cell, wherein the LIC cell is a laminate cell or a prismatic cell.

The disclosed technology has the advantages of having two ultra-thin (thickness less than or equal to 50 μm) single-sided positive electrodes, one ultra-thin (thickness less than or equal to 50 μm) double-sided negative electrode preloaded with an ultra-thin lithium film (u-Li) with holes on the surface, a separator, and an ultra-thin (thickness less than or equal to 1 mm) LIC of an organic solvent electrolyte using lithium salt as an electrolyte.

Advantages of the disclosed technology include an unexpected solution to the problem of creating Lithium Ion Capacitor (LIC) batteries that are excellent in cycling capability and DC life, with high energy and power densities. In a preferred embodiment of the LIC battery system of the invention, the negative electrode is pre-doped with lithium ions by applying a lithium source comprising an ultra-thin lithium film with holes to the surface of the negative electrode.

When pre-doped in this way, there are many factors that can affect the electrochemical performance and capacity of an LIC cell. These factors include: (1) Materials for positive and negative electrodes, including active materials and additives; (2) a method of manufacturing a positive electrode and a negative electrode; (3) thicknesses of the positive and negative electrodes; (4) A thickness ratio of a total thickness of the positive electrode active layer to a total thickness of the negative electrode active layer; (5) Capacity ratio of positive electrode active layer to negative electrode active layer; (6) a material for a separator of an LIC battery; (7) A mass per unit area of a lithium source comprising an ultra-thin lithium film having pores preloaded onto a surface of a negative electrode; (8) Thickness of lithium source containing ultra-thin lithium film having pores loaded on the surface of negative electrode; (9) An area design of an ultra-thin lithium film having holes preloaded onto a surface of a negative electrode and a hole area design on the ultra-thin lithium film having holes; (10) The mass ratio percentage of the lithium source containing the ultra-thin lithium film having the pores, preloaded onto one side surface of the negative electrode, to the one side negative electrode active layer.

An advantage of the disclosed technology is an LIC battery comprising: a positive electrode without a polymeric binder; a negative electrode having a surface preloaded with a polymer binder free of a lithium source comprising an ultra-thin lithium film having pores; a diaphragm; and an organic solvent electrolyte using a lithium salt as an electrolyte.

In some embodiments, the positive electrode active material is activated carbon, carbon black, CNT, or an activated carbon/carbon black/CNT blend (AC/CB/CNT). In the LIC cell of the invention, the negative electrode active material is preferably graphite, hard carbon and soft carbon or any possible mixture of the above materials.

In some embodiments, the positive electrode active material Activated Carbon (AC) has a particle size of 1000 to 3000m ² Surface area in the range of/g.

In some embodiments, the positive electrode active material Activated Carbon (AC) has a particle size D50. Ltoreq.10 μm and the negative electrode active material has a particle size D50. Ltoreq.10 μm.

In some embodiments, the positive electrode formulation may be adjusted over a range of AC/CB to CNT mass ratios. The mass ratio between AC and CB is 80:20 to 99:1.

In some embodiments, the total thickness of the positive electrode is 40 μm to 450 μm, including the thickness of the double-sided conductive material pre-coated aluminum foil and the thickness of the double-sided active material layer. In the LIC battery of the present invention, the total thickness of the negative electrode, including the thickness of the double-sided conductive material pre-coated copper foil and the thickness of the double-sided active material layer, is 20 μm to 350 μm. In the LIC battery of the invention, the thickness ratio of the total thickness of the positive electrode active layer to the total thickness of the negative electrode active layer is preferably 1:2 to 3:1.

In some embodiments, the capacity ratio of the positive electrode active layer to the negative electrode active layer is preferably 1:12 to 1:2.

In some embodiments, it is preferred that in an LIC cell, the separator material is a cellulose, polypropylene (PP) and Polyethylene (PE) based material.

In some embodiments, the lithium source comprising an ultrathin lithium film with holes loaded onto one side surface of the negative electrode preferably has a mass per unit area of 0.1mg/cm ² To 3mg/cm ² 。

In some embodiments, the thickness of the lithium source comprising an ultra-thin lithium film having pores preloaded onto one side surface of the negative electrode is preferably 2 to 50 μm.

In some embodiments, the area of the ultrathin lithium film with holes as a lithium source preloaded onto the negative electrode surface is preferably about 25% to about 100% of the negative electrode area.

In some embodiments, the area size percentage of the pores in the ultra-thin lithium film with pores as a lithium source preloaded onto the negative electrode surface preferably ranges from about 0.01% to about 75%.

In some embodiments, the mass ratio of the lithium source including the ultra-thin lithium film having holes preloaded onto both side surfaces of the negative electrode to the both side negative electrode active layers is preferably 7% to 14%.

In some embodiments, an ultra-thin (thickness less than or equal to 50 μm) LIC battery is provided that includes two ultra-thin (thickness less than or equal to 50 μm) single-sided positive electrodes, one ultra-thin (thickness less than or equal to 50 μm) double-sided negative electrode preloaded with an ultra-thin lithium film (u-Li) having pores on the surface, a separator, and an organic solvent electrolyte that uses lithium salt as an electrolyte.

In some embodiments, an LIC battery having high energy density, high power density, and long life performance is provided.

With respect to the above description, it will be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, material, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. Thus, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

As used herein, certain acronyms should be associated with the following terms: dimethyl carbonate (DMC); lithium difluoro (oxalato) borate (LiDFOB); lithium bis (fluorosulfonyl) imide (LiFSI); propylene Carbonate (PC); ethylene Carbonate (EC); ethyl Methyl Carbonate (EMC); ethylene glycol monobutyl Ether (EB); diethyl carbonate (DEC); vinylene Carbonate (VC); boron Carbon Nitride (BCN); lithium difluoro (oxalato) borate (LiDFOB); lithium bis (oxalato) borate (LiBOB); lithium difluorobis (oxalato) phosphate (LiDFOP); lithium bis (trifluoromethanesulfonyl) imide (LiTFSI).

Various other components may be included and invoked to provide aspects of the teachings herein. For example, additional materials, combinations of materials, and/or omissions of materials may be used to provide additional embodiments within the scope of the teachings herein. Many modifications of the teachings herein may be made. In general, modifications may be designed according to the needs of a user, designer, manufacturer, or other similar interested party. Modifications may be intended to meet certain performance criteria that are deemed important by the parties described above.

The appended claims or claim elements should not be construed to refer to 35u.s.c. ≡112 (f) unless the word "means for … …" or "steps for … …" is explicitly used in the particular claims.

When introducing elements of the present invention or the embodiments thereof, the articles "a/an" and "the" are intended to mean that there are one or more of the elements. Similarly, the adjective "another" when used to introduce an element is intended to mean one or more elements. The terms "comprising" and "having" are intended to be inclusive such that there may be additional elements other than the listed elements. As used herein, the term "exemplary" is not intended to imply a best example. Indeed, "exemplary" refers to an instance of an embodiment of one of many possible embodiments.

While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications will be appreciated by those skilled in the art to adapt a particular instrument, situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims (44)

1. A lithium ion capacitor device, comprising:

a positive electrode comprising a carbon network substantially free of binder material;

a negative electrode comprising a carbon network substantially free of binder material, the negative electrode being separated from the positive electrode by a separator; and

a lithium film disposed on the negative electrode to provide 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;

a plurality of electrode active material particles disposed in the void space within the network and embedded 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 a length ratio of each of the major dimensions is at least 10 times a length ratio of the minor dimensions.

3. The apparatus of any preceding claim, wherein the high aspect ratio carbon elements comprise elements each having two major dimensions and one minor dimension, wherein the length ratio of each of the major dimensions is at least 100 times the length ratio of the minor dimensions.

4. The apparatus of any preceding claim, wherein the high aspect ratio carbon elements comprise elements each having two major dimensions and one minor dimension, wherein the length ratio of each of the major dimensions is at least 1,000 times the length ratio of the minor dimensions.

5. The apparatus of any preceding claim, wherein the high aspect ratio carbon elements comprise elements each having two major dimensions and one minor dimension, wherein the length ratio of each of the major dimensions is at least 10,0000 times the length ratio of the minor dimensions.

6. The apparatus of any preceding claim, wherein the high aspect ratio carbon elements comprise elements each having one major dimension and two minor dimensions, wherein the length ratio of each of the major dimensions is at least 10 times the length ratio of each of the minor dimensions.

7. The apparatus of any preceding claim, wherein the high aspect ratio carbon elements comprise elements each having one major dimension and two minor dimensions, wherein the length ratio of each of the major dimensions is at least 100 times the length ratio of each of the minor dimensions.

8. The apparatus of any preceding claim, wherein the high aspect ratio carbon elements comprise elements each having one major dimension and two minor dimensions, wherein the length ratio of each of the major dimensions is at least 1,000 times the length ratio of each of the minor dimensions.

9. The apparatus of any preceding claim, wherein the high aspect ratio carbon elements comprise elements each having one major dimension and two minor dimensions, wherein the length ratio of each of the major dimensions is at least 10,000 times the length ratio of each of the minor dimensions.

10. The apparatus of any preceding claim, wherein the high aspect ratio carbon element comprises carbon nanotubes or bundles of carbon nanotubes.

11. The apparatus of any preceding claim, wherein the high aspect ratio carbon element comprises graphene flakes.

12. The apparatus of any preceding claim, wherein the electrode active layer contains less than 10 wt% polymeric binder disposed in the void space.

13. The apparatus of any preceding claim, wherein the electrode active layer contains less than 1 wt% polymeric binder disposed in the void space.

14. The apparatus of any preceding claim, wherein the electrode active layer contains less than 1 wt% polymeric binder disposed in the void space.

15. The device of any preceding claim, wherein the electrode active layer is substantially free of polymeric materials other than surface treatments.

16. The device of any preceding claim, wherein the electrode active layer is substantially free of polymeric material.

17. The apparatus of any preceding claim, wherein the network is at least 90 wt% carbon.

18. The apparatus of any preceding claim, wherein the network is at least 95 wt% carbon.

19. The apparatus of any preceding claim, wherein the network is at least 99 wt% carbon.

20. The apparatus of any preceding claim, wherein the network is at least 99.9 wt% carbon.

21. The apparatus of any preceding claim, wherein the network comprises an electrically interconnected network of carbon elements exhibiting connectivity above a percolation threshold.

22. The apparatus of any preceding claim, wherein the network defines one or more highly conductive paths.

23. The apparatus of claim 29, wherein the path has a length greater than 100 μιη.

24. The apparatus of claim 29, wherein the path has a length greater than 1,000 μιη.

25. The apparatus of claim 29, wherein the path has a length greater than 10,000 μιη.

26. The apparatus of any preceding claim, wherein the network comprises one or more structures formed from the carbon elements, the structures comprising a total length of at least ten times the length of the largest dimension of the carbon elements.

27. The apparatus of any preceding claim, wherein the network comprises one or more structures formed from the carbon elements, the structures comprising a total length of at least 100 times the length of the largest dimension of the carbon elements.

28. The apparatus of any preceding claim, wherein the network comprises one or more structures formed from the carbon elements, the structures comprising a total length of at least 1,000 times the length of the largest dimension of the carbon elements.

29. The apparatus of any preceding claim, wherein the positive electrode comprises an electrode active material comprising at least one of the list consisting of: activated carbon, carbon black, graphite, hard carbon, soft carbon, nano-form carbon, high aspect ratio carbon, and mixtures thereof.

30. The apparatus of any preceding claim, wherein the positive electrode comprises an electrode active material having Activated Carbon (AC) with a specific surface area in the range of 1000 to 3000m 2/g.

31. The apparatus of any preceding claim, wherein the positive electrode comprises an electrode active material having Activated Carbon (AC) with a particle size d50+.10 μm.

32. An apparatus according to any preceding claim, wherein the negative electrode comprises an electrode active material having a particle size d50+.10 μm.

33. The apparatus of any preceding claim, wherein the positive electrode comprises an electrode active material having Activated Carbon (AC), carbon Black (BC), and high aspect ratio carbon, wherein a mass ratio between the active material and the high aspect ratio carbon is in the range of 80:20 to 99:1.

34. The apparatus of any preceding claim, wherein the total combined thickness of the positive electrode and the lithium film is in the range of 40 μιη to 450 μιη.

35. An apparatus according to any preceding claim, wherein the total thickness of the negative electrode is in the range 20 μm to 350 μm.

36. The apparatus of any preceding claim, wherein a thickness ratio of a total thickness of the positive electrode active layer to a total thickness of the negative electrode active layer is in a range of 1:2 to 3:1.

37. The apparatus of any preceding claim, wherein the capacity ratio of the positive electrode active layer to the negative electrode active layer is in the range of 1:12 to 1:2.

38. The apparatus of any preceding claim, wherein the lithium film comprises an ultra-thin lithium film having pores.

39. The apparatus of any preceding claim, wherein the mass per unit area of the lithium source on the side of the negative electrode active layer is at 0.1mg/cm ² To 3mg/cm ² Within a range of (2).

40. The apparatus of any preceding claim, wherein the thickness of the lithium source on the side of the negative electrode active layer is in the range of 2 to 50 μιη.

41. The apparatus of any preceding claim, wherein the surface area of the lithium film is about 25% to about 100% of the surface area of the side of the negative electrode.

42. The apparatus of any preceding claim, wherein the lithium membrane comprises pores, and wherein the area size percentage of the pores ranges from about 0.01% to about 75% of the total area of the membrane.

43. A method for manufacturing a lithium ion capacitor, comprising:

providing an energy storage battery by

Selecting a positive electrode comprising a carbon network substantially free of binder material;

Selecting a negative electrode comprising a carbon network substantially free of binder material, the negative electrode being separated from the positive electrode by a separator; and

disposing a lithium film on the negative electrode to provide pre-lithiation of the capacitor;

the energy storage cell and electrolyte are sealed in a housing to provide the capacitor.

44. The method of claim 43, wherein the lithium ion capacitor comprises the apparatus of any one of claims 1 to 42.

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