JP2023545832A - Advanced lithium-ion energy storage device - Google Patents

Abstract

Abstract: A lithium ion capacitor includes a binder-free positive electrode active layer and a negative electrode active layer. This capacitor exhibits high energy density, power density and cycle life, providing a good compromise in performance between electric double layer capacitors and lithium ion batteries. [Selection diagram] Figure 1

Description

CROSS-REFERENCE TO RELATED REFERENCES This application is incorporated by reference in U.S. Provisional Patent Application No. 63/093441, entitled "Advanced Lithium-Ion Energy Storage Device," filed October 19, 2020; lyte U.S. Provisional Patent Application No. 63/021492 entitled "Composite Electrode" issued March 24, 2020, U.S. Patent No. 10,600,582 entitled "Composite Electrode" issued April 7, 2015, "High power and high U.S. Patent No. 9,001,495 entitled “Energy storage media for ultracapacitors” issued December 22, 2015. , No. 218,917. , the entire disclosures of which are incorporated herein by reference for all purposes.

TECHNICAL FIELD The invention disclosed herein relates to energy storage devices, and specifically to lithium-containing electrodes made substantially without binder materials.

Lithium (Li) ion batteries (LiB) and electric double layer capacitors (EDLC) are two widely used electrochemical energy storage devices. A typical LiB is made with a lithium (Li) intercalated anode and a Li metal oxide cathode (hence the reductive process or Faradic mechanism of energy storage), whereas EDLC is made with an anode and a cathode. are fabricated using high surface area activated carbon (AC) for both (thus relying on double layer capacitance or non-Faradaic forms of energy storage). As a result of their various energy storage mechanisms, these devices differ in their energy and power performance. Although LiB exhibits high specific energy, for example 100-250 Wh/kg, LiB also has a low specific power of <0.5 kW/kg and an insufficient cycle life of <5,000 cycles. Although EDLC has a high specific power of 10 kW/kg and a long cycle life of over 100,000 cycles, EDLC exhibits a much lower specific energy of less than 6 Wh/kg.

Energy storage devices that can combine the advantages of LiB and EDLC in a single form are highly desirable. As a new generation of supercapacitors, Li-ion capacitor (LiC) is an advanced energy storage device that includes an EDLC cathode and a prelithiated anode, and is charged between the EDLC cathode and the prelithiated anode. and ions are shuttled back and forth during the discharge process. Due to the use of prelithiated, low surface anode materials, LiC can be charged to voltages as high as 4.0V, which is much higher than EDLC and comparable to LiB. Although LiC can achieve much higher power density than LiB, the energy density of LiC is about 10-20 Wh/kg, which is still much lower than LiB. Therefore, the energy density of LiC energy storage devices needs to be further improved.

Methods and apparatus are needed to future-proof LiC technology. Preferably, there is a need for a method and apparatus that further reduces the cost and time required for manufacturing.

In one embodiment, a lithium ion capacitor device is provided. The device includes a positive electrode comprising a network of carbon substantially free of binder material, a negative electrode comprising a network of carbon substantially free of binder material separated from the positive electrode by a separator, and a prelithium capacitor. a film of lithium disposed on the negative electrode to provide oxidation, and at least one of the positive and negative electrodes includes a network of high aspect ratio carbon elements defining voids within the network; and a plurality of electrode active material particles arranged in a network and entangled in a network.

In some embodiments, the high aspect ratio carbon element includes an element each having two major dimensions and one minor dimension, wherein the ratio of the lengths of each of the major dimensions is at least 10 times the length of the minor dimension. It is. High aspect ratio carbon elements can include elements each having two major dimensions and one minor dimension, the ratio of the length of each of the major dimensions being at least 100 times the length of the minor dimension. High aspect ratio carbon elements can include elements each having two major dimensions and one minor dimension, the ratio of the length of each of the major dimensions being at least 1,000 times the length of the minor dimension. High aspect ratio carbon elements can include elements each having two major dimensions and one minor dimension, where the ratio of the length of each of the major dimensions is at least 10,0000 times the length of the minor dimension. High aspect ratio carbon elements can include elements each having one major dimension and two minor dimensions, where the ratio of the lengths of each of the major dimensions is at least 10 times the length of each of the minor dimensions. A high aspect ratio carbon element can include an element each having one major dimension and two minor dimensions, where the ratio of the lengths of each of the major dimensions is at least 100 times the length of each of the minor dimensions. High aspect ratio carbon elements can include elements each having one major dimension and two minor dimensions, the ratio of the lengths of each of the major dimensions being at least 1,000 times the length of each of the minor dimensions. . High aspect ratio carbon elements can include elements each having one major dimension and two minor dimensions, the ratio of the lengths of each of the major dimensions being at least 10,000 times the length of each of the minor dimensions. . High aspect ratio carbon elements may include carbon nanotubes or carbon nanotube bundles. High aspect ratio carbon elements may include graphene flakes. The electrode active layer may contain less than 10% by weight of polymer binder disposed in the voids. The electrode active layer may contain less than 1% by weight of polymer binder disposed in the voids. The electrode active layer may contain less than 1% by weight of polymer binder disposed in the voids. The electrode active layer may be substantially free of polymeric materials other than the surface treatment. The electrode active layer may be substantially free of polymeric material. The network may be at least 90% carbon by weight. The network may be at least 95% carbon by weight. The network may be at least 99% carbon by weight. The network can be at least 99.9% carbon by weight. The network may include an electrically interconnected network of carbon elements that exhibit connectivity above a percolation threshold. The network may define one or more highly conductive paths. The pathway may have a length of more than 100 μm. The pathway can have a length of more than 1,000 μm. The pathway can have a length of more than 10,000 μm. The network may include one or more structures formed of carbon elements, the structures having an overall length that is at least 10 times the length of the largest dimension of the carbon elements. The network may include one or more structures formed of carbon elements that include an overall length that is at least 100 times the length of the largest dimension of the carbon elements. The network may include one or more structures formed of carbon elements, the structures having an overall length that is at least 1,000 times the length of the largest dimension of the carbon elements. The positive electrode may include an 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. The positive electrode may include an electrode active material including activated carbon (AC) with a specific surface area of 1000-3000 m ² /g. The positive electrode may include an electrode active material including activated carbon (AC) having a particle size D50≦10 μm. The negative electrode may include an electrode active material having a particle size D50≦10 μm. The positive electrode may include an electrode active material including activated carbon (AC), carbon black (BC), and high aspect ratio carbon, and the mass ratio of active material to high aspect ratio carbon is from 80:20 to 99:1. Within range. The total thickness of the positive electrode and lithium membrane can 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 capacitance ratio between the positive electrode active layer and the negative electrode active layer is within the range of 1:12 to 1:2. The lithium membrane may include an ultrathin lithium membrane that includes pores. The mass per unit area of the lithium source on the side facing the negative active layer may be in the range of 0.1 mg/cm 2 to 3 mg/cm ² . The thickness of the lithium source on the side of the negative active electrode layer may be in the range of 2-50 μm. The surface area of the lithium film can be about 25% to about 100% of the lateral surface area of the negative electrode. The lithium membrane may include pores, the area size percentage range of the pores being within a range of about 0.01% to about 75% of the total area of the membrane.

In another embodiment, a method of making a lithium ion capacitor is provided. The method includes selecting a positive electrode comprising a network of carbon substantially free of binder material and selecting a negative electrode comprising a network of carbon substantially free of binder material separated from the positive electrode by a separator. disposing a film of lithium on the negative electrode to provide prelithiation of the capacitor; and encapsulating the energy storage cell and electrolyte within the housing to provide the capacitor. including providing a storage cell. Lithium ion capacitors may include the devices described above.

BRIEF DESCRIPTION OF THE DRAWINGS The features and advantages of the invention will be apparent from the following description in conjunction with the accompanying drawings.

A series of micrographs, flowcharts and performance graphs are provided.

Disclosed herein are methods and apparatus for making hybrid binder-free electrodes useful in energy storage devices. Advantageously, the electrodes disclosed herein can provide superior electrical performance and require fewer steps in the manufacturing process because they are substantially free of binder materials traditionally used in electrode construction. can do.

The energy storage devices disclosed herein combine the advantages of LiB and LiC while avoiding the inherent deficiencies and bridge the gap between the high energy density provided by LiB and the high power density exhibited in LiC. It is something that fills in the In particular, the fundamental difference between this Li-ion energy storage device and LiC is that hybrid Li-ion technology combines the two by synergistically combining LiB and LiC cathode materials together to form a hybrid composite cathode. It integrates separate energy storage devices into one. Non-faradic capacitor materials can be initially charged electrostatically until the electrode potential reaches the reduction reaction potential of the faradaic cell material, when the cell material is charged while maintaining a constant cell reduction reaction potential. can. Once fully charged, the capacitor material is charged again until the limiting potential of the capacitor material is reached.

Generally, the disclosed technology includes a binder-free hybrid composite cathode electrode, a binder-free anode electrode, a separator, an organic solvent electrolyte solution containing a lithium salt as an electrolyte, and an ultrathin lithium film (μ-Li) source. Relating to a hybrid lithium ion energy storage device. The ultrathin lithium membrane may contain multiple pores. Due to the ultra-thin lithium film, the anode electrode is pre-doped with sufficient lithium ions. Pre-doping may occur by placing an ultra-thin lithium film substantially on the surface of the anode electrode. Additionally, the hybrid composite cathode may be made using a polymeric binder-free manufacturing process, and the resulting capacity ratio of the hybrid composite cathode to the anodic electrode may be between 0.1 and 1.2. The mass of the ultrathin lithium film disposed on the anode electrode may be predetermined by a formula to achieve high energy, power, and long cycle life performance in a full cell format design.

A schematic diagram of an energy storage device is shown in FIG. In the example of FIG. 1, energy storage device (ESD) 10 is a three-layer cell. The opposing current collector 2 is the host for the cathode material 3. Collectively, current collector 2 and cathode material 3 provide each of the two cathodes 4 shown. An anode 8 is shown arranged between the cathodes 3. In this example, anode 8 comprises opposing layers of anode material 5 disposed on another current collector 6 . A lithium source 7 is placed above each layer of anode material. In this example, the current collector 2 for the cathode is made from aluminum, and the current collector 6 for the anode is made from copper.

Referring to FIGS. 2A and 2B, an example of a cathode material 3 comprising activated carbon is shown. In these figures, SEM images of a cathode material 3 according to 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 inferred, has greater energy storage than the device of FIG. 2A. It is possible.

Two examples of cathode materials are provided herein for discussion. The first example includes an electrode with pure activated carbon (AC) (LiC with 0% lithium iron phosphate (LFP)), and the second example includes a hybrid binder-free electrode (20:80 LFP to AC ). In binder-free electrodes, the carbon structure provided provides excellent bonding with the active material and serves to bind the cathodes together without the need for traditional polymers or similar non-conducting or low-conducting binders. . As a result of not including a (non-conductive) binder, the carbon structure provides higher electrical conductivity and higher cell performance. In this disclosure, a commercially available dry method AC binder-based electrode is used as a baseline for comparison.

Generally, binder materials are non-conductive or low conductivity materials that are added to the electrode material to promote the mechanical integrity of the electrode layer and good adhesion to the current collector. The use of binder materials replaces other materials capable of energy storage and conduction, reducing the power output of the energy storage cells used. An example of a binder is PVDF. Polyvinylidene fluoride (PVDF) is a highly non-reactive thermoplastic fluoropolymer produced by the polymerization of vinylidene difluoride. PVDF is commonly used for the cathode. A common anode binder material is a styrene-butadiene copolymer.

Similarly, anode material 5 is shown in FIGS. 3A, 3B and 3C. FIG. 3A shows an SEM of hard carbon powder. FIG. 3B shows a prior art anode 8 made from hard carbon powder and binder material. FIG. 3C shows an embodiment of an anode 8 according to the teachings herein.

For purposes of illustration, the anode 8 presented herein was composed of hard carbon (HC) as the active material. A slurry mixture for the anode was made, which included HC with a particle size (D50) of 2 μm and carbon nanotubes (CNT and CMC) with carboxymethyl cellulose acting as the binder material. In this example, the mass ratio of the three components was 98.33:0.67:1. After producing the slurry, it was coated on a copper (Cu) foil substrate with a thickness of 10 μm. The electrodes were then dried in an oven at 160 degrees Celsius for 3 hours with a stream of air. An anode electrode sheet was prepared in which the thickness of the active material layer on one side was approximately 75 μm and the tap density was 1.0 g/cm ³ . The porosity of the hard carbon anode was approximately 50 percent. The electrodes were then cut to the desired dimensions (4.6 cm x 4.6 cm (active area) for the anode and 4.5 cm x 4.5 cm for the cathode) from the electrode sheet and then vacuumed at 120 degrees Celsius overnight. After drying and transfer to a dry room environment, the final cell was assembled there. The electrodes were assembled into the configuration shown in FIG.

In the assembly of ESD 10, a lithium source 7 was incorporated into all anodes 8. In each embodiment, the lithium source 7 comprised an ultrathin lithium membrane with pores therein. Holes were cut from a 20 μm Li metal sheet (99.9% purity). Lithium Source 7 provided a lithium source for prelithiation with various sizes for fabricating various LFP/AC hybrid composite cathode-based LiB/LiC cells. Based on the first lithium intercalation specific capacity of the HC anode, which was about 372 mAh/g, the amount of u-Li with pores preloaded on the surface of the HC anode to completely prelithiate the HC. was determined to be approximately 10% (u-Li preload mass/anode active layer mass). In the cell design for LiC (0% LFP), the cathode to anode capacity ratio is approximately 0.14 (1:7), so it was determined that the anode should be prelithiated (with approximately 10% lithium loading). did. This LiC cell design allows LiC to have long cycles and high energy and power densities. However, when there is LFP mixed in the hybrid composite binder-free cathode, the LFP provides an additional source of lithium from the hybrid cathode when charging to the maximum operating voltage. In order to avoid the growth of lithium dendrites within the anode during cell charging, the actual mass loading of the lithium source 7 (i.e. the ultrathin lithium membrane with pores) placed on the surface of the anode is The lithium source portion provided by the LFP should be taken into account and should therefore be less than 10% of the anode active layer weight. It can be concluded that the decrease in lithium source 7 at the anode is likely to correlate with the increase in LFP at the cathode.

During cell assembly, charging of the lithium source 7 was performed in a dry chamber environment. An ultrathin lithium membrane was placed under pressure. An example of an assembled ESD 10 follows the scheme shown in FIG. The anode was a double-sided HC anode preloaded with a lithium source with holes and sandwiched between two single-sided LFP/AC composite cathodes. The electrolyte used was 1M LiPF6 in a 1:1 mixture by weight of ethylene carbonate (EC) and dimethyl carbonate (DMC). All pouch cell assembly was performed in a dry room environment (dew point -40°C). Figure 4 shows the charge/discharge profiles collected during initial testing.

Figure 4 shows initial test results of LiC with binder-free AC and HC electrodes under different current charging and discharging. Test conditions for these examples included 83.1% cathode porosity, 64.1% anode porosity. Cell voltage ranged from 3.8 to 2.2V, capacitance was 11.2F, ESR was 0.127Ω, and RC constant was 1.4 seconds. The specific energy and energy density based on weight and volume of the cathode and anode active layers were determined to be 36.6 Wh/kg and 20.1 Wh/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 69.7 kW/kg and 35.3 kW/L, respectively.

As a result, with this cell design, the specific energy and energy density of a full-sized multilayer 1000F LiC pouch cell can be 9Wh/kg and 16Wh/L, which is higher than the competing 1000FLiC energy density (13.7Wh/L). estimated to be substantially higher. Furthermore, with this cell design, it is estimated that the ESR of a full-sized multilayer 1000F LIC pouch cell can be 1.4mohm, which is lower than the ESR of a competing 1000F LIC cell (1.6mohm). Table 1 below provides a more detailed comparison with the prior art.

As can be seen from the comparison in Table 1, the ESR of the binder-free electrode system LiC was 30.6% lower than the binder-based (i.e., prior art) control sample. Similarly, the RC constant of LiC with binder-free electrodes was only 1.4 seconds, while the binder-based LiC had an RC constant of 5.1 seconds. The maximum specific power and power density of LiC based on the binder-free electrode were 131.6 percent and 64.6 percent higher, respectively, than the binder-based (i.e., prior art) control sample. FIG. 5A shows the comparative ESR and FIG. 5B is an exploded view of the curve shown in FIG. 5A. Aspects of the second embodiment that were tested are introduced in FIGS. 6A, 6B, 7A and 7B.

In the second embodiment, comparative performance was investigated using soft carbon and AC and LFP binder-free electrodes. The ratio of SC:CNT:CMC was the same as the HC slurry, and this time 20 percent LFP was added to the carbon framework along with activated carbon (AC) to achieve a hybrid composite electrode. FIGS. 6A and 6B are micrographs of soft carbon-based electrodes. 7A and 7B are micrographs of AC and LFP binder-free electrodes. Assembly of the storage cell follows the same procedure as the first embodiment outlined above. The physical aspects of the storage cells are shown in Table 2.

In Table 2, control cells (ie, prior art soft carbon) are identified as A53 and A21. Storage cells made without binder are identified as B43 and B44. The electrolyte used in the storage cell was as follows. A53: 1.0M _LiPF6 +1% VC in EC/DMC; A21: 1.0M _LiPF6 +0.1M LiDFOB in EC/EMC/MB (20:20:60 by volume); B43: EC/EMC/ 1.0M LiFSI + 1% VC in DEC/PC (20:46.7:23.3:10 by volume); and B44:EC/EB/DEC/PC (20:46.7:23.3 by volume) 10) 1.0M LiFSI + 1% VC in. The initial charge-discharge profiles of the storage cells were 0.25 and 12.5 mA/cm2 (10 and 500 mA). Figure 8 shows the charge/discharge performance of four cells. This includes the initial constant current charge and discharge along with the ESR results.

Figure 9 shows the results of the low temperature test. The A53 was not included in the charge/discharge test because it did not operate below -45 degrees Celsius. In tests, A21 showed the highest capacity retention (approximately 40 percent) at -45 degrees Celsius. B44 showed the second highest capacity retention (approximately 30 percent) at minus 45 degrees Celsius. Based on the cell design, the specific energy of the LIC is approximately 22.4 Wh/kg, with 30 percent retention being 6.7 Wh/kg, which is still half of the original design of 13 Wh/kg. LFP additives appeared to reduce capacity retention for low temperature tests. FIG. 10 provides comparative performance for soft carbon and hard carbon anodes. In Figure 10 it can be seen that B44 shows the best impedance compared to the other two electrolytes. For EIS, the hard carbon anode performed slightly better than the soft carbon anode for LIC, as indicated by the smaller semicircle in the graph.

The third embodiment was directed to optimization of electrolyte formulations for both high and low temperatures. In this embodiment, Y4 was the electrolyte control sample and was 1.0 M LiTFSI, EC/EMC/MB (20:20:60 by volume) + 1 percent VC. Y5 and Y5.1 were BCN solvent-based electrolytes containing LiTFSI salts with additives including VC, FEC, LiDFOB, LiBOB, LiDFOP, _LiNO3 . The electrolyte formulation for Y5 is 1.0M LiTFSI in BCN/EC/VC (80/10/10 by volume) and the electrolyte formulation for Y5.1 is BCN/EC/VC (80/10 by volume). 1.0M LiTFSI+1% _OS3 in /10), a commercially available additive.

FIG. 11 is a graph showing ESR performance as a function of temperature for three different types of electrolytes. It was found that at low temperatures of minus 40 degrees Celsius, the binder-free LIC has an ESR increase of 3.4 Ω, while the conventional binder-based LIC has an ESR increase of 5.1 Ω. Using the Y5 electrolyte, the cell also passed the long-term cycle life test, and the results can be seen in FIG. 12. FIG. 12 shows a room temperature high C rate cycle life test of LIC using electrolyte. Y5: The voltage range is 3.8 to 2.2V, and the current is about 500mA.

In the fourth embodiment, the performance of both high temperature (85 degrees Celsius) and low temperature (-55 degrees Celsius) electrolyte formulations was evaluated. Y7 was assigned to a BCN solvent-based electrolyte with LiTFSI salts, with co-solvents including GBL (gamma-butyrolactone), VC, FEC, and additives including LiDFOB, LiBOB, LiDFOP, _LiNO3 , etc. The Y7 electrolyte formulation is 1.0M LiTFSI in BCN/GBL/VC/OS ₃ (74.5/12.5/10/3 by volume). Figures 13-15 show the results of high temperature cycling and direct charging of LIC using Y7 electrolyte. Y7 has the same low temperature performance of -55 degrees Celsius as Y5 and Y5.1. Figure 13 shows the cycle life performance plot of a cell with Y7 electrolyte charged and discharged from 3.8V to 2.2V under a constant current of 500mA, capacitance/ESR retention as a function of number of cycles, with a cycling environment in degrees Celsius. It is 85 degrees. FIG. 14 shows the discharge curves at various number of cycles during LIC cycling at 85 degrees Celsius based on Y7 electrolyte. FIG. 15 shows a comparison of discharge curves after holding a constant voltage at 3.8 V (float test) at 85 degrees Celsius for around 330 hours.

A method of making a storage cell according to the teachings herein is illustrated in FIG.

In some embodiments, the positive electrode used is comprised of a sheet metal current collector with a conductive material coated on both sides, and a positive electrode active material and CNTs formed on both sides of the current collector. The electrode includes an electrode layer. The negative electrode used in this LIC laminate cell is composed of a sheet metal current collector having a conductive material coated on both sides, a negative electrode active material and additives, and electrode layers formed on both sides of the current collector. An electrode comprising:

The current collector used for the positive electrode may be made from aluminum, stainless steel, or other materials. In some of the examples presented, aluminum is used. The current collector used for the negative electrode can be constructed from stainless steel, copper, nickel, etc., and in some of the examples presented, copper is used. Generally, the thickness of the positive and negative electrode current collectors is in the range of about 5-50 μm. In the example presented, the range is 8-25 μm. Within this range, the resulting positive and negative electrodes have high strength, and the conductive paint slurry can be easily applied. The coating accuracy, volumetric energy density, and gravimetric energy density of conductive materials can be improved. A carbon conductive paint slurry is applied to both sides of the positive electrode current collector and negative electrode current collector by a spray coating method, and dried to obtain a current collector having conductive layers for both the positive electrode and the negative electrode. Ta. The thickness of the carbon conductive coating on one side of the current collector is 1-20 μm. In the examples presented, the thickness ranged from 3 to 12 μm.

The above-mentioned electrode active materials can be used for the positive electrode and the negative electrode. Specifically, the positive/negative electrode active material powder, CNTs, and some solvent are dispersed and mixed in a blender/mixer to obtain a wet slurry mixture. Preferably, the percentage of additives added to the powder/slurry mixture is between 2 percent and 12 percent. For positive electrode manufacture, the slurry may be made without a binder. Next, a slurry-like mixture is applied onto the substrate, which is the positive electrode active material layer. The thickness of the positive electrode active layer is between 30 and 250 μm, or in some embodiments between 50 and 200 μm. The binder-free electrode is then calendered with hot hot mill rollers at high temperatures to form the final positive electrode for the LIC cell with the desired porosity and pressing density. The positive electrode active material, additives, and deionized water/IPA as a solvent are first mixed in a mixer for a sufficient time to form a uniform wet slurry. The slurry is then coated on both sides of the carbon conductive precoated current collector by an electrode coating machine equipped with a drying oven so that the coated electrodes can be dried. The coating machine gap can be adjusted according to the initial thickness requirements of electrode fabrication. The dried electrode is then pressed through a hot press calender to the desired active layer thickness to form the final positive electrode of the LIC cell. The thickness of the positive electrode active layer based on the wet slurry preparation method on one side of the current collector is between 3 and 250 μm, and in some embodiments between 5 and 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. The slurry is then coated on both sides of the carbon conductive precoated current collector by an electrode coating machine equipped with a drying oven so that the coated electrodes can be dried. The coating machine gap can be adjusted according to the initial thickness requirements of electrode manufacturing. The dried electrode is then pressed down through a hot press calender to the desired active layer thickness to form the final negative electrode for the LIC cell. The thickness of the negative electrode active layer based on the wet slurry preparation method on one side of the current collector is between 3 and 200 μm, with 5 and 160 μm being used in some embodiments.

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

Generally, the positive electrode used comprises a sheet metal current collector with a conductive material coated on both sides, and an electrode layer formed on both sides of the current collector, consisting of a positive electrode active material and CNTs. It is an electrode containing. The negative electrode used in the LIC laminate cell of the present invention is composed of a sheet metal current collector having a conductive material coated on both sides, a negative electrode active material and additives, and is formed on both sides of the current collector. It is an electrode including an electrode layer.

Generally, the Li source preloaded onto the surface of the negative electrode is an ultrathin Li film with pores. The ultrathin Li film with pores is described in detail in U.S. patent application Ser. No. 15/489,813, which is incorporated herein by reference in its entirety. is applied on the surface of all prefabricated negative electrodes by the manufacturing method of laminating negative electrodes with. The production can be carried out in a drying room with a dew point below -45°C. The pressure of the lamination rolls can be between 40 kg/cm ² and 400 kg/cm ² . In some embodiments of the LiC cells presented herein, the mass per unit area of the ultrathin Li film with filled pores on one surface of the negative electrode is between 0.1 mg/cm ² and 3 mg /cm ² is preferable. The thickness of the ultrathin Li film with holes preloaded on one side of the negative electrode is preferably 2 to 50 μm. The length of the ultra-thin Li film having pores as a Li source filled in the surface of the negative electrode may be 30 mm to 250 mm. The width of the Li film may be 30 mm to 150 mm. The area of the ultrathin Li film having pores as a Li source filled in the surface of the negative electrode may be about 25% to about 100% of the area of the negative electrode. The area size percentage range of the pores in the ultrathin Li film with the pores as a Li source filled on the surface of the negative electrode may be about 0.01% to about 75%. The mass ratio percentage of the ultrathin Li film with holes preloaded on both sides of the negative electrode to the negative electrode active layers on both sides is preferably 7% to 14%. After all the ultrathin Li films with holes are pressed onto the negative electrode, there can be a uniform thin layer Li source position distribution on the surface of the negative electrode.

In some embodiments of the LiC cells presented herein, the electrodes, including a positive electrode and a negative electrode with a lithium source preloaded on their surfaces, are preloaded with some additional Cut to the specified size along with the current collector tab. The size of the electrodes determines the final size of the LIC cell, as the outer container must match the size of the electrodes. In some embodiments, the length and width of the negative electrode is 0.5 mm to 5 mm greater than that of the positive electrode of the LiC cell. In some embodiments of LiC cells presented herein, the length of the cut positive and negative electrodes may be between 30 mm and 250 mm, and the width of the cut positive and negative electrodes may be between 30 mm and 250 mm. , 30mm to 150mm.

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

In LiC, activated carbon may be used as the positive electrode (PE), while the negative electrode (NE) material may include various materials such as soft carbon, hard carbon, graphite, etc.

Cell components and design can be modified to improve the electrochemical performance of LiC. This is the active material selected for PE, NE active material and CNT and the thickness/mass of the PE vs. NE active layer (without current collectors including aluminum (Al) and copper (Cu)). ratio, PE to NE active layer capacitance ratio. PE and NE size design and number of layers, type of material for the separator, electrolyte composition, and NE prelithiation method. In the case of PE, the active material can be binder-free activated carbon (AC). In the case of NE, the active material can be hard carbon (HC), soft carbon (SC), graphite (G) and other carbon-based materials, and the network of CNTs with CMC is a strong material for the active material. may depend on producing a unique carbon structure. The material of the separator can be polypropylene (PP), polyethylene (PE) and cellulose or other similar materials.

In some embodiments of LiC cells presented herein, the cell core unit is formed by laminating the positive and negative electrodes through separators within an outer container, such as a laminated outer container. The negative electrode is predoped by pressing a lithium source containing an ultrathin Li film with holes on the surface of the negative electrode. "Pre-doping" roughly refers to the phenomenon in which lithium ions invade the negative electrode active layer. The ultrathin Li film with pores is the lithium ion source for predoping the negative electrode. The lithium source filling process ensures that the negative electrode contains uniform lithium on the surface, so that when filled with the electrolyte, the negative electrode can be smoothly and uniformly predoped with lithium ions.

In some embodiments of 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 lamination and welding process, the electrode unit is housed in a container, for example an aluminum lamination case suitable for the size of the electrode unit, and a three-sided heat sealing process is applied. The desired amount of electrolyte was then filled into the LIC laminate cell and the cell was immersed to begin the pre-doping process by intercalation of lithium into the negative electrode. After the cell has been soaked for a sufficient period of time, a vacuum sealing process is applied to the cell to remove excess gas trapped within the LIC laminate cell. As a result, such a configuration can be realized in the LIC laminate cell.

The organic electrolyte can be a Li-ion battery electrolyte containing Li salts. Prelithiation of the NE may be performed to ensure that the LIC can achieve the desired electrochemical performance. Some prelithiation methods, including electrochemical (EC) and external short circuit (ESC) methods, utilize a piece of Li metal as a sacrificial third electrode to predope a graphite or HC electrode with lithium. be done. In the EC prelithiation method, NE and Li metals are separated by a separator in a lithium salt-based organic electrolyte, and the predoping process can be carried out by an electronic charger controlling the charging current or voltage.

It is desirable that the positive electrode active material can reversibly adsorb or desorb lithium ions and anions in an electrolyte such as tetrafluoroborate. An example of such an active material is activated carbon powder. The activated carbon has a specific surface area of 1,500 m ² /g to 2,800 m ² /g, preferably 1,600 m ² /g to 2,400 m ² /g. The activated carbon preferably has a 50% cumulative volume diameter (D50) (average particle diameter) of 2 μm to 10 μm. In order to further improve the energy density and output density of the LIC laminate cell, it is particularly preferable that the thickness is 3 μm or more and 8 μm or less. Some other examples of such materials may be carbon black and activated carbon/carbon black/CNT composites (AC/CB/CNT).

It is desirable that the negative electrode active material is capable of reversible intercalation and deintercalation of lithium ions. Examples of such active materials include graphite-based composite particles, difficult-to-graphitize carbon (hard carbon, (HC)), easy-to-graphitize carbon (soft carbon, (SC)), and the like. In some embodiments, negative electrode active materials, HC and SC particles, are preferred because they can achieve higher performance in power performance and cycling stability than graphite materials. However, graphite materials can achieve higher energy performance for LICs because graphite has a higher specific capacity than HC and SC. To improve the output performance of LIC cells, the negative electrode active material has a 50% cumulative volume diameter (D50) in the range of 1.0 to 10 μm, and in some embodiments preferably 2 to 6 μm. It is preferable to use HC and SC having a particle size that falls within the range.

Note that it is difficult to produce HC and SC particles with a 50% cumulative volume diameter (D50) of less than 10 μm. When the 50% cumulative volume diameter (D50) of HC and SC particles exceeds 10 μm, it becomes difficult to realize an LIC cell with sufficiently low internal resistance. In some embodiments, the negative electrode active material has a specific surface area of 0.1-200 m ² /g, more preferably 0.6-60 m ² /g. This range was set because if the specific surface area of the negative electrode active material is less than 0.1 m ² /g, the resistance of the LIC cell can be increased, and if the specific surface area of the negative electrode active material is less than 200 m ² /g. This is because the larger the value, the higher the irreversible capacity during charging of the LIC laminate cell.

In the ESC prelithiation method, the NE and sacrificial Li metal third electrodes are shorted through an external wire connection. However, with conventional prelithiation methods, it takes time for the lithium to dissipate and for the cell to become fully lithiated to NE in the LIC laminate cell. The cost of this method adds up to the amount of time it takes. Additionally, in traditional prelithiation methods, both the PE and NE current collectors must be porous to create a path for lithium ions to migrate from the Li metal electrode through the LIC laminate cell; This also increases the manufacturing cost of the electrode.

The techniques for prelithiation disclosed herein address some of these issues. That is, by filling the surface of the NE with an ultra-thin lithium film (abbreviated as u-Li) having pores, it is possible to accelerate the cell fabrication process and accelerate prelithiation. Since Li metal can be coated directly onto the carbon electrode, the current collector does not need to be porous to intercalate Li ions into the NE. After impregnating the cell with electrolyte, the Li source on the surface of the NE electrochemically reacts with the carbon electrode active layer and intercalates within the NE.

Some advantages of the technology disclosed herein are now presented.

An advantage of the disclosed technology is a lithium ion capacitor (LIC) with excellent lifetime characteristics, including cycle life and DC life, while maintaining high energy density and power density.

Advantages of the disclosed technology include a binder-free positive electrode, a negative electrode preloaded with a lithium source on the surface called an ultrathin lithium membrane (U-Li) with pores, a separator, and a lithium salt as an electrolyte. and an organic solvent electrolyte solution.

An advantage of the disclosed technology is that the positive electrode active material is preferably activated carbon, carbon black, CNT, and activated carbon/carbon black/CNT mixture (AC/CB/CNT), and the negative electrode active material is hard carbon. , soft carbon, graphite, CNT, and any possible mixtures of the above materials are preferred LIC cells.

An advantage of the disclosed technology is a LIC cell in which the positive electrode active material activated carbon (AC) has a surface area in the range of 1000-3000 m ² /g.

An advantage of the disclosed technology is a LIC cell in which the positive electrode active material activated carbon (AC) has a particle size D50≦10 μm and the negative electrode active material has a particle size D50≦10 μm.

An advantage of the disclosed technology is an LIC cell in which a polymer binder is not used in the cathode material, which increases electrode conductivity and improves power performance.

An advantage of the disclosed technology is a LIC cell in which the positive electrode formulation can be tailored in a range of mass ratios between AC/CB and CNT/carbon framework. Also, no or substantially no polymer binder is used.

An advantage of the disclosed technology is an LIC cell in which the additives for manufacturing the negative electrode used in the LIC cell are preferably CNTs and carboxymethyl cellulose (CMC).

An advantage of the disclosed technology is a LIC cell in which the negative electrode formulation can be tailored over a range of mass ratios between 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, including the thickness of the double-sided conductive material pre-coated aluminum (Al) foil and the thickness of the double-sided active material layer, is between 40 μm and 450 μm.

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

An advantage of the disclosed technology is a LIC cell where the thickness ratio between the total thickness of the positive electrode active layer and the total thickness of the negative electrode active layer is preferably between 1:2 and 3:1.

An advantage of the disclosed technology is a LIC cell in which the capacitance ratio between the positive electrode active layer and the negative electrode active layer is preferably between 1:12 and 1:2.

An advantage of the disclosed technology is LIC cells where the separator material is cellulose, polypropylene (PP) and polyethylene (PE) based materials.

An advantage of the disclosed technology is that the mass per unit area of the Li source, which includes an ultra-thin lithium film with pores filled on one surface of the negative electrode, is 0.1 mg/cm ² to 1. Preferably, it is 3 mg/cm ² in a LIC cell.

An advantage of the disclosed technology is a LIC cell where the Li source ultrathin Li film (u-Li) with filled pores on one side surface of the negative electrode preferably has a thickness of 2-50 μm.

An advantage of the disclosed technology is that the area of the ultrathin Li film (u-Li) with holes as a preloaded Li source on one surface of the negative electrode is about 25% to about 100% of the area of the negative electrode. % of the LIC cell.

An advantage of the disclosed technology is that the LIC cell has pores as a preloaded Li source on the surface of the negative electrode, and the area size percentage range of the pores in the ultrathin Li film is from 0.01% to about 75%. It is.

An advantage of the disclosed technology is that the LIC cell comprises an ultrathin Li film with preloaded pores on one side surface of the negative electrode, and the mass percentage of the Li source to the one side negative electrode active layer is 7%. It is preferably 14%.

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

The advantages of the disclosed technology are two ultrathin (≦50 μm thick) single-sided positive electrodes and one ultrathin (≦50 μm thick) single-sided positive electrode with holes preloaded on the surface of the ultrathin lithium film (U-Li). It is an ultrathin (≦1 mm thick) LIC with a double-sided negative electrode (50 μm), a separator, and an organic solvent electrolyte solution with a lithium salt as electrolyte.

Advantages of the disclosed technology include an unexpected solution to the problem of creating lithium ion capacitor (LIC) cells with excellent cycling capability and DC lifetime, and high energy and power densities. In a preferred embodiment of the LIC cell system of the present invention, the negative electrode is pre-doped with lithium ions by applying a lithium source comprising an ultrathin Li film with pores on the surface of the negative electrode.

When pre-doped in this way, there are many factors that affect the electrochemical performance and capacity of the LIC cell. These factors include: (1) Materials used for the positive and negative electrodes, including active materials and additives, (2) Methods of manufacturing the positive and negative electrodes, (3) Thickness of the positive and negative electrodes, (4) Positive The thickness ratio between the total thickness of the electrode active layer and the total thickness of the negative electrode active layer, (5) the capacitance ratio between the positive electrode active layer and the negative electrode active layer, (6) the material of the separator for the LIC cell, ( 7) mass per unit area of the Li source comprising an ultra-thin Li film with pre-loaded pores on the surface of the negative electrode; (8) comprising an ultra-thin Li film with pre-loaded pores on the surface of the negative electrode. Thickness of the Li source, (9) Area design of the ultra-thin Li film with holes preloaded on the surface of the negative electrode and pore area design on the ultra-thin Li film with holes, (10) One side surface of the negative electrode Mass percentage of a Li source comprising an ultrathin Li film with holes preloaded on top of the negative electrode active layer on one side.

Advantages of the disclosed technology include a polymeric binder-free positive electrode, a polymeric binder-free negative electrode preloaded on the surface with a lithium source comprising an ultrathin lithium membrane with pores, a separator, and an organic LIC cell comprising a solvent electrolyte solution.

In some embodiments, the positive electrode active material is activated carbon, carbon black, CNT or activated carbon/carbon black/CNT mixture (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 surface area in the range of 1000-3000 m ² /g.

In some embodiments, the positive electrode active material activated carbon (AC) has a particle size D50≦10 μm and the negative electrode active material has a particle size D50≦10 μm.

In some embodiments, the positive electrode formulation can be tailored in a range of mass ratios between AC/CB and CNTs, where the mass ratio between AC and CB is from 80:20 to 99:1. can.

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

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

In some embodiments, in LIC cells, the separator material is preferably cellulose, polypropylene (PP) and polyethylene (PE) based materials.

In some embodiments, the mass per unit area of the Li source comprising an ultrathin Li film with filled pores on one surface of the negative electrode is between 0.1 mg/cm ² and 3 mg/cm ² . is a preferred LIC cell.

In some embodiments, the thickness of the Li source, which includes an ultrathin Li film with preloaded holes on one surface of the negative electrode, is preferably between 2 and 50 μm.

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

In some embodiments, the areal size percentage range of the pores in the ultrathin Li film with the pores as a preloaded Li source on the surface of the negative electrode is about 0.01% to about 75%. It is preferable.

In some embodiments, the mass percentage of the Li source comprising an ultrathin Li film with preloaded holes on both sides of the negative electrode to the negative electrode active layer on both sides is between 7% and 14%. is preferred.

In some embodiments, two ultrathin (≦50 μm thick) single-sided positive electrodes and one ultrathin (≦50 μm thick ) An ultrathin (≦1 mm thick) LIC cell is provided with a double-sided negative electrode, a separator, and an organic solvent electrolyte solution with a lithium salt as electrolyte.

Some embodiments provide LIC cells with high energy density, high power density, and long life performance.

With respect to the above description, the optimum dimensional relationships of the parts of the present invention, including variations in size, material, shape, form, function, and methods of operation, assembly, and use, will be readily apparent and obvious to those skilled in the art. It is to be understood that all relationships equivalent to those shown in the drawings and described herein are intended to be encompassed by the present invention. Accordingly, the above is to be considered merely illustrative of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desirable to limit the invention to the precise construction and operation shown and described, and therefore all suitable modifications and equivalents are contemplated. are included within the scope of the present invention.

As used herein, certain acronyms refer to the following terminology: 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 referenced 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. Various modifications of the teachings herein may be implemented. In general, modifications may be designed according to the needs of users, designers, manufacturers, or other similar stakeholders. Modifications may be intended to meet certain criteria of performance deemed important by that party.

The appended claims or claim elements do not invoke 35 U.S.C. 112(f) unless the words "means for" or "steps for" are explicitly used in a particular claim. should not be construed as doing so.

When introducing elements of the invention or its embodiments, the articles "a," "an," and "the" are intended to mean that one or more of the elements are present. Similarly, the adjective "another" when used to introduce an element is intended to mean one or more elements. The terms "including" 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 the best example. Rather, "exemplary" refers to an example embodiment that is one of many possible embodiments.

Although the invention has been described with reference to illustrative embodiments, it will be apparent to those skilled in the art that various changes can be made and elements thereof can be replaced by equivalents without departing from the scope of the invention. will be understood. Additionally, those skilled in the art will recognize many modifications to adapt a particular apparatus, situation, or material to the teachings of the invention without departing from the essential scope thereof. Therefore, the invention is not limited to the particular embodiments disclosed as the best mode contemplated for carrying out the invention, but rather the invention covers all is intended to include embodiments.

Claims (44)

A lithium ion capacitor device,
a positive electrode comprising a network of carbon substantially free of binder material;
a negative electrode comprising a network of carbon substantially free of binder material, separated from the positive electrode by a separator;
a film of lithium disposed on the negative electrode to provide prelithiation of the capacitor;
At least one of the positive electrode and the negative electrode,
said network of high aspect ratio carbon elements defining voids within the network;
A lithium ion capacitor device comprising: a plurality of electrode active material particles disposed in the voids in the network and entangled in the network. 5. The high aspect ratio carbon element comprises an element each having two major dimensions and one minor dimension, wherein the ratio of the lengths of each of the major dimensions is at least 10 times the length of the minor dimension. The device according to item 1. The high aspect ratio carbon element includes an element each having two major dimensions and one minor dimension, and the ratio of the length of each of the major dimensions is at least 100 times the length of the minor dimension. , a device according to any one of the preceding claims. The high aspect ratio carbon element includes an element each having two major dimensions and one minor dimension, and the ratio of the length of each of the major dimensions is at least 1,000 times the length of the minor dimension. Apparatus according to any one of the preceding claims. The high aspect ratio carbon element includes an element 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 the length of the minor dimension. Apparatus according to any one of the preceding claims. The high aspect ratio carbon element includes an element each having one major dimension and two minor dimensions, and the ratio of the length of each of the major dimensions is at least 10 times the length of each of the minor dimensions. Apparatus according to any one of the preceding claims. The high aspect ratio carbon element includes an element each having one major dimension and two minor dimensions, and the ratio of the length of each of the major dimensions is at least 100 times the length of each of the minor dimensions. Apparatus according to any one of the preceding claims. The high aspect ratio carbon element includes an element each having one major dimension and two minor dimensions, the ratio of the length of each of the major dimensions being at least 1, 10. A device according to any one of the preceding claims, wherein the device is multiplied by a factor of 000. The high aspect ratio carbon element includes an element each having one major dimension and two minor dimensions, wherein the ratio of the length of each of the major dimensions is at least 10 of the length of each of the minor dimensions. 10. A device according to any one of the preceding claims, wherein the device is multiplied by a factor of 000. 7. The apparatus of any one of the preceding claims, wherein the high aspect ratio carbon element comprises a carbon nanotube or a bundle of carbon nanotubes. 7. The apparatus of any one of the preceding claims, wherein the high aspect ratio carbon elements comprise graphene flakes. 7. The device of any one of the preceding claims, wherein the electrode active layer contains less than 10% by weight of polymeric binder disposed within the voids. 7. The device of any one of the preceding claims, wherein the electrode active layer contains less than 1% by weight of polymeric binder disposed within the voids. 7. The device of any one of the preceding claims, wherein the electrode active layer contains less than 1% by weight of polymeric binder disposed within the voids. 7. A device according to any one of the preceding claims, wherein the electrode active layer is substantially free of polymeric material other than a surface treatment. 7. A device according to any preceding claim, wherein the electrode active layer is substantially free of polymeric material. 7. A device according to any one of the preceding claims, wherein the network is at least 90% by weight carbon. 7. A device according to any preceding claim, wherein the network is at least 95% by weight carbon. 7. A device according to any preceding claim, wherein the network is at least 99% carbon by weight. 7. A device according to any preceding claim, wherein the network is at least 99.9% carbon by weight. 7. A device according to any one of the preceding claims, wherein the network comprises an electrically interconnected network of carbon elements exhibiting connectivity above a percolation threshold. 7. The apparatus of any one of the preceding claims, wherein the network defines one or more highly conductive paths. 30. The apparatus of claim 29, wherein the path has a length greater than 100 [mu]m. 30. The apparatus of claim 29, wherein the path has a length greater than 1,000 [mu]m. 30. The apparatus of claim 29, wherein the path has a length greater than 10,000 [mu]m. 10. The network according to any one of the preceding claims, wherein the network comprises one or more structures formed of the carbon elements, the structures comprising a total length of at least 10 times the length of the largest dimension of the carbon elements. The device described. 10. The network according to any one of the preceding claims, wherein the network comprises one or more structures formed of the carbon elements, the structures comprising a total length of at least 100 times the length of the largest dimension of the carbon elements. The device described. Any one of the preceding claims, wherein the network comprises one or more structures formed of 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. The equipment described in section. 12. The preceding claim, wherein the positive electrode comprises an 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. A device according to any one of the above. Apparatus according to any one of the preceding claims, wherein the positive electrode comprises an electrode active material comprising activated carbon (AC) with a specific surface area in the range from 1000 to 3000 m2/g. 7. The device according to any one of the preceding claims, wherein the positive electrode comprises an electrode active material comprising activated carbon (AC) with a particle size D50≦10 μm. 7. The device according to any one of the preceding claims, wherein the negative electrode comprises an electrode active material having a particle size D50≦10 μm. The positive electrode includes an electrode active material containing activated carbon (AC), carbon black (BC), and high aspect ratio carbon, and the mass ratio of the active material to the high aspect ratio carbon is 80:20 to 99: 1. A device according to any one of the preceding claims. A device according to any one of the preceding claims, wherein the total thickness of the positive electrode and the lithium film is in the range 40 μm to 450 μm. Apparatus according to any one of the preceding claims, wherein the total thickness of the negative electrode is in the range 20 μm to 350 μm. The device according to any one of the preceding claims, 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. . A device according to any one of the preceding claims, wherein the capacitance ratio between the positive electrode active layer and the negative electrode active layer is in the range of 1:12 to 1:2. 7. The device of any one of the preceding claims, wherein the lithium membrane comprises an ultrathin lithium membrane containing pores. The device according to any one of the preceding claims, wherein the mass per unit area of the Li source on the sides of the negative active layer is in the range from 0.1 mg/cm ² to 3 mg/cm ² . Apparatus according to any one of the preceding claims, wherein the thickness of the Li source on the sides of the negative active electrode layer is in the range 2-50 μm. 7. The device of any preceding claim, wherein the surface area of the lithium film is about 25% to about 100% of the lateral surface area of the negative electrode. 10. The lithium membrane of any one of the preceding claims, wherein the lithium membrane includes pores, and the area size percentage range of the pores is within the range of about 0.01% to about 75% of the total area of the membrane. Device. A method for manufacturing a lithium ion capacitor, the method comprising:
selecting a positive electrode comprising a network of carbon substantially free of binder material;
selecting a negative electrode comprising a network of carbon substantially free of binder material, separated from the positive electrode by a separator;
disposing a film of lithium on the negative electrode to provide prelithiation of the capacitor;
providing an energy storage cell by: sealing the energy storage cell and electrolyte in a housing to provide the capacitor. 44. A method according to claim 43, wherein the lithium ion capacitor comprises a device according to any one of claims 1 to 42.

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