Compositions and methods for pre-lithiating energy storage devices

Abstract

The present application provides compositions and methods for pre-lithiating energy storage devices. An energy storage device may include a positive electrode, a negative electrode, and a separator between the positive electrode and the negative electrode. At least one of the electrodes may include an electrode film prepared by a dry process. The electrode membrane and / or the electrode may include a pre-lithiated material. Methods and apparatus for making electrodes and / or electrode films are also described.

Description

[0001] This application is a divisional application of Chinese patent application No. 202080021164.6, with an application date of January 14, 2020 and an invention name of “Compositions and methods for pre-lithiation energy storage devices”.

[0002] Any priority application incorporated by reference

[0003] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 792,544, filed on January 15, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0004] The present invention relates to energy storage devices, and in particular to compositions and methods of making electrodes for energy storage devices. Background Art

[0005] Various types of energy storage devices can be used to power electronic devices, including, for example, capacitors, batteries, capacitor-battery hybrids, and / or fuel cells. Energy storage devices with electrodes prepared using improved electrode formulations and / or manufacturing methods, such as traditional or solid-state lithium ion capacitors or batteries, can promote improved capacitor electrical performance. Lithium ion capacitors or batteries with electrodes prepared using improved electrode formulations and / or manufacturing methods can exhibit improved cycle performance, reduced equivalent series resistance (ESR) values, increased power density performance, and / or increased energy density performance. Improved electrode formulations and / or manufacturing methods can also promote lower costs for energy storage device manufacturing. Summary of the invention

[0006] In order to summarize the present disclosure and the advantages achieved relative to the prior art, certain objects and advantages of the present disclosure are described herein. In any particular embodiment, not all of these objects or advantages can be achieved. Thus, for example, those skilled in the art will recognize that the present invention can be implemented or performed in a manner that achieves or optimizes one advantage or a group of advantages taught herein without having to achieve other objects or advantages taught or suggested herein.

[0007] In a first aspect, a dry electrode membrane of an energy storage device is provided. The dry electrode membrane includes a dry active material. The dry electrode membrane also includes a dry binder. The dry electrode membrane further includes a prelithiating material distributed throughout the dry active material and the dry binder. The dry electrode membrane is free-standing.

[0008] In some embodiments of the dry electrode film, the intervening lithiation material is Li2O2. In some embodiments, the dry active material is a dry positive electrode active material. In some embodiments, the dry positive electrode active material comprises sulfur or a sulfur-containing material.

[0009] In a second aspect, a method for manufacturing a dry electrode membrane for an energy storage device is provided. The method includes mixing an interlithiated material and a dry conductive carbon additive to form a first dry mixture. The method also includes mixing the first dry mixture with a dry active material to form a second dry mixture. The method also includes adding a dry fibrillable binder to the second dry mixture to form a dry electrode membrane mixture. The method also includes fibrillating the dry binder in the dry electrode membrane mixture.

[0010] In some embodiments of the method, the method further comprises calendering the dry electrode film mixture to form a self-supporting dry electrode film. In some embodiments, mixing the first dry mixture with the dry active material further comprises mixing the dry carbon material and the dry conductive carbon material to form a second dry mixture. In some embodiments, the intervening lithiation material and the dry conductive carbon additive are mixed so that the temperature of the first mixture is at most about 100°C. In some embodiments, the intervening lithiation material and the dry conductive carbon additive result in electrical contact between the primary particles of the pre-lithiation material and the conductive carbon additive. In some embodiments, the intervening lithiation material and the dry conductive carbon additive are mixed without overheating the first dry mixture. In some embodiments, the ratio of the intervening lithiation material to the dry conductive carbon additive is about 5:1 to about 5:3.

[0011] All of these embodiments are intended to fall within the scope of the invention disclosed herein. These and other embodiments will become apparent to those skilled in the art from the following detailed description of the preferred embodiments with reference to the accompanying drawings, the invention not being limited to any particular preferred embodiment disclosed. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] These and other features, aspects, and advantages of the present disclosure are described with reference to the accompanying drawings of certain embodiments, which are intended to illustrate certain embodiments rather than to limit the present invention.

[0013] Figure 1 is a schematic cross-sectional view of a pre-lithiation energy storage device according to one embodiment.

[0014] Figure 2 is a process flow diagram showing an example of a method for manufacturing an electrode membrane from an electrode membrane mixture containing a pre-lithiation material.

[0015] Figure 3A A SEM image of the as-received lithium peroxide is shown.

[0016] Figure 3B Shown is an SEM image of lithium peroxide mixed with SuperP carbon black in a 5 to 2 ratio.

[0017] Figure 4 An image of a laminated electrode comprising lithium peroxide immersed in water is shown.

[0018] Figure 5 The electrochemical curves of an electrochemical cell containing 2% lithium peroxide were compared to a control cell containing no lithium peroxide. DETAILED DESCRIPTION

[0019] The present disclosure relates to an electrode film including a pre-lithiation material for an energy storage device and a method for manufacturing the same. For example, the pre-lithiation material can be incorporated into the electrode film to compensate for lithium consumed when a solid electrolyte interphase (SEI) layer is formed on the electrode during the initial cycle of the corresponding energy storage device. The reaction of the pre-lithiation material can also generate gas, which can beneficially increase the porosity of the electrode.

[0020] definition

[0021] As used herein, the terms "battery" and "capacitor" should be given their ordinary and customary meanings as understood by those of ordinary skill in the art. The terms "battery" and "capacitor" are not mutually exclusive. A capacitor or battery may refer to a single electrochemical cell that may operate alone or as a component of a multi-battery system.

[0022] As provided herein, "self-supporting" electrode film is an electrode film combined with a binder matrix structure, which is sufficient to support the film or layer and maintain its shape so that the electrode film or layer can be self-supporting. When incorporated into an energy storage device, a self-supporting electrode film or active layer (active layer) is a kind of combined with this binder matrix structure. Generally, and depending on the method adopted, such an electrode film or active layer is strong enough to be used in the energy storage device manufacturing process without any external support elements (such as current collectors, support webs or other structures), although the support element can be used to promote the energy storage device manufacturing process. For example, a "self-supporting" electrode film can have enough strength to be rolled up, processed and unfolded in the electrode manufacturing process without other support elements. Dry electrode film, such as positive electrode film or negative electrode film, can be self-supporting.

[0023] As provided herein, a "solvent-free" electrode film is an electrode film that contains no detectable processing solvent, processing solvent residues, or processing solvent impurities. A dry electrode film, such as a positive electrode film or a negative electrode film made with only dry components, can be solvent-free.

[0024] A "wet" electrode, "wet process" electrode or slurry electrode is an electrode prepared by at least one step or comprises an electrode film prepared by at least one step involving a slurry of active material, binder and optional additives, even if a subsequent drying step removes water from the electrode or electrode film. Thus, a wet electrode or wet electrode film will include at least one or more processing solvents, processing solvent residues and / or processing solvent impurities.

[0025] Unless expressly stated otherwise or otherwise understood in the context of use, conditional language such as "can," "could," "might," or "may" is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements, and / or steps. Thus, such conditional language is generally not intended to imply that one or more embodiments are in any way required of features, elements, and / or steps, or that one or more embodiments must include logic for determining, with or without user input or prompting, whether such features, elements, and / or steps are included or will be performed in any particular embodiment.

[0026] Unless specifically stated otherwise, conjunctions such as the phrase "at least one of X, Y, and Z" are generally understood in context to convey that an item, term, etc. can be X, Y, or Z. Thus, such conjunctions are generally not intended to imply that certain embodiments require the presence of at least one of X, at least one of Y, and at least one of Z.

[0027] Language of degree as used herein, such as the terms "approximately," "about," "generally," and "substantially" as used herein, means a value, amount, or characteristic that is close to a described value, amount, or characteristic, which can still perform a desired function or achieve a desired result. For example, the terms "approximately," "about," "generally," and "substantially" can refer to an amount within less than 10%, less than 5%, less than 1%, less than 0.1%, and less than 0.01% of the described amount, depending on the desired function or desired result.

[0028] describe

[0029] Although certain embodiments and examples are described below, it will be appreciated by those skilled in the art that the invention extends beyond the specifically disclosed embodiments and / or uses and obvious modifications and equivalents thereof. Therefore, it is intended that the scope of the invention disclosed herein should not be limited by any specific embodiments described below.

[0030] In an attempt to increase the energy density of lithium-ion electrochemical devices, high specific energy density negative electrode materials, such as silicon, have been explored. During the first charge, the lithium in the positive electrode material is consumed during the formation of a solid electrolyte interphase (SEI) layer, which acts as a protective layer around the negative electrode. However, during normal operation of the electrochemical device, the lithium ions consumed in the formation of this SEI layer are no longer available for circulation, which results in reduced performance potential. Described below are electrode film compositions and formation processes that allow the introduction of pre-lithiation materials into an electrode film mixture for forming a pre-lithiation electrode film. Some embodiments avoid or reduce the decomposition of pre-lithiation materials due to exposure to solvents and high temperatures. In addition, in some embodiments, such pre-lithiation materials can have the additional benefit of producing a pre-lithiation electrode with increased porosity.

[0031] Figure 1 A schematic side cross-sectional view of an example of a pre-lithiated energy storage device 100 having a pre-lithiated electrode film is shown. The energy storage device 100 can be classified as, for example, a capacitor, a battery, a capacitor-battery hybrid, or a fuel cell. In one embodiment, the device 100 is a lithium-ion battery.

[0032] The device has a first electrode 102, a second electrode 104, and a separator 106 located between the first electrode 102 and the second electrode 104. The first electrode 102 and the second electrode 104 are adjacent to respective opposing surfaces of the separator 106. The energy storage device 100 includes an electrolyte 118 to facilitate ionic communication between the electrodes 102, 104 of the energy storage device 100. For example, the electrolyte 118 can be in contact with the first electrode 102, the second electrode 104, and the separator 106. The electrolyte 118, the first electrode 102, the second electrode 104, and the separator 106 are housed within an energy storage device housing 120.

[0033] One or more of the first electrode 102, the second electrode 104, and the separator 106, or a combination thereof, may include a porous material. The pores within the porous material may provide a containment and / or increased surface area for contact with the electrolyte 118 within the housing 120. The energy storage device housing 120 may be sealed around the first electrode 102, the second electrode 104, and the separator 106, and may be physically sealed from the surrounding environment.

[0034] In some embodiments, the first electrode 102 can be a negative electrode ("negative electrode"), and the second electrode 104 can be a positive electrode ("positive electrode"). The separator 106 can be configured to electrically isolate two electrodes adjacent to opposite sides of the separator 106, such as the first electrode 102 and the second electrode 104, while allowing ionic communication between the two adjacent electrodes. The separator 106 may include a suitable porous electrically insulating material. In some embodiments, the separator 106 may include a polymer material. For example, the separator 106 may include a cellulose material (e.g., paper), a polyethylene (PE) material, a polypropylene (PP) material, and / or a polyethylene and polypropylene material.

[0035] Typically, the first electrode 102 and the second electrode 104 each include a current collector and an electrode film. The electrodes 102 and 104 include electrode films 112 and 114 with high electrode film density and / or high electron density, respectively. As shown, the electrodes 102 and 104 each have a single electrode film 112 and 114, but other combinations with two or more electrode films for each electrode 102 and 104 are possible. The device 100 is shown as having a single electrode 102 and a single electrode 104, but other combinations are possible. The electrode films 112 and 114 can each have any suitable shape, size, and thickness. For example, the electrode film may each have a thickness of about 30 microns (μm) to about 250 microns, for example, about or at least about 50 microns, about 100 microns, about 150 microns, about 200 microns, about 250 microns, about 300 microns, about 400 microns, about 500 microns, about 750 microns, about 1000 microns, about 2000 microns or any range of values ​​therebetween. For a single electrode film, additional electrode film thickness is described throughout the disclosure. The electrode film generally comprises one or more active materials, for example, a negative electrode active material or a positive electrode active material as provided herein. Electrode film 112 and / or 114 may be a dry and / or self-supporting electrode film as provided herein, and have advantageous properties, such as thickness, increased electrode film density, energy density, specific energy density, areal energy density, areal capacity or specific capacity, as provided herein. The first electrode film 112 and / or the second electrode film 114 may also include one or more binders as provided herein. Electrode films 112 and / or 114 may be prepared by methods described herein. Electrode films 112 and / or 114 may be wet or self-supporting dry electrodes as described herein.

[0036] like Figure 1As shown, the first electrode 102 and the second electrode 104 respectively include a first current collector 108 in contact with the first electrode film 112 and a second current collector 110 in contact with the second electrode film 114. The first current collector 108 and the second current collector 110 promote electrical coupling between each corresponding electrode film and an external circuit (not shown). The first current collector 108 and / or the second current collector 110 include one or more conductive materials and may have any suitable shape and size selected to promote the transfer of charge between the corresponding electrode and the external circuit. For example, the current collector may include a metal material, such as a material including aluminum, nickel, copper, rhenium, niobium, tantalum, and a precious metal such as silver, gold, platinum, palladium, rhodium, osmium, iridium and alloys, and a combination of the foregoing. For example, the first current collector 108 and / or the second current collector 110 may include, for example, aluminum foil or copper foil. The first current collector 108 and / or the second current collector 110 may have a rectangular or substantially rectangular shape, and its size is set to provide charge transfer between the corresponding electrode and the external circuit.

[0037] Continue to refer Figure 1 , the second electrode film 114 is pre-lithiated. However, it should be understood that the first electrode film 112 may be pre-lithiated, or both the electrode films 112 and 114 may be pre-lithiated. The electrode films 112 and / or 114 may be pre-lithiated as described herein.

[0038] In some embodiments, the energy storage device 100 is filled with a suitable lithium-containing electrolyte 118. For example, the device 100 may include a lithium salt and a solvent, such as a non-aqueous or organic solvent. Typically, the lithium salt includes a redox-stable anion. In some embodiments, the anion may be monovalent. In some embodiments, the lithium salt may be selected from hexafluorophosphate (LiPF6), lithium tetrafluoroborate (LiBF4), lithium perchlorate (LiClO4), bis(trifluoromethanesulfonyl)imide lithium (LiN(SO2CF3)2), lithium trifluoromethanesulfonate (LiSO3CF3), lithium bis(oxalatoborate) (LiBOB) and combinations thereof. In some embodiments, the electrolyte may include quaternary ammonium cations and anions selected from the group consisting of hexafluorophosphate, tetrafluoroborate and iodide anions. In some embodiments, the salt concentration may be from about 0.1 mol / L (M) to about 5M, from about 0.2M to about 3M or from about 0.3M to about 2M. In other embodiments, the salt concentration of the electrolyte may be from about 0.7M to about 1M. In certain embodiments, the salt concentration of the electrolyte may be about 0.2 M, about 0.3 M, about 0.4 M, about 0.5 M, about 0.6 M, about 0.7 M, about 0.8 M, about 0.9 M, about 1 M, about 1.1 M, about 1.2 M, or any range of values ​​therebetween.

[0039] In some embodiments, the energy storage device electrolyte as provided herein may include a liquid solvent. As provided herein, the solvent does not need to dissolve each component of the electrolyte, nor does it need to completely dissolve any component of the electrolyte. In other embodiments, the solvent may be an organic solvent. In some embodiments, the solvent may include one or more functional groups selected from carbonates, ethers and / or esters. In some embodiments, the solvent may include carbonates. In other embodiments, carbonates may be selected from cyclic carbonates, such as, for example, ethylene carbonate (EC), propylene carbonate (PC), vinyl ethylene carbonate (VEC), vinylene carbonate (VC), fluoroethylene carbonate (FEC) and combinations thereof, or acyclic carbonates, such as, for example, dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC) and combinations thereof. In certain embodiments, the electrolyte may include LiPF6 and one or more carbonates.

[0040] In some embodiments, the lithium ion battery is configured to operate at about 2.5 to 4.5 V or 3.0 to 4.2 V. In other embodiments, the lithium ion battery is configured to have a minimum operating voltage of about 2.5 V to about 3 V, respectively. In other embodiments, the lithium ion battery is configured to have a maximum operating voltage of about 4.1 V to about 4.4 V, respectively.

[0041] In some embodiments, a method for manufacturing an energy storage device is provided. In other embodiments, the method includes selecting a negative electrode and a positive electrode. In some embodiments, selecting the negative electrode includes selecting a dry self-supporting negative electrode or a wet negative electrode. In other embodiments, selecting the positive electrode includes selecting a dry self-supporting positive electrode or a wet positive electrode. The step of selecting a dry negative electrode can include selecting an active material processing method and selecting a binder processing method.

[0042] In some embodiments, the electrode film provided herein includes at least one active material and at least one binder.At least one active material can be any active material known in the art.At least one active material can be a material suitable for the negative electrode or positive electrode of a storage battery.The negative electrode active material can include, for example, an insertion material (e.g., carbon, graphite and / or graphene), an alloying / dealloying material (e.g., silicon, silicon oxide, tin and / or tin oxide), a metal alloy or compound (e.g., Si-Al and / or Si-Sn) and / or a conversion material (e.g., manganese oxide, molybdenum oxide, nickel oxide and / or copper oxide).The negative electrode active material can be used alone or mixed together to form a multiphase material (e.g., Si-C, Sn-C, SiOx-C, SnOx-C, Si-Sn, Si-SiOx, Sn-SnOx, Si-SiOx-C, Sn-SnOx-C, Si-Sn-C, SiOx-SnOx-C, Si-SiOx-Sn or Sn-SiOx-SnOx).

[0043] The positive electrode active material may include, for example, a metal oxide, a metal sulfide, or a lithium metal oxide. The lithium metal oxide may be, for example, lithium nickel manganese cobalt oxide (NMC), lithium manganese oxide (LMO), lithium iron phosphate (LFP), lithium cobalt oxide (LCO), lithium titanate (LTO), and / or lithium nickel cobalt aluminum oxide (NCA). In some embodiments, the positive electrode active material may include, for example, a layered transition metal oxide (e.g., LiCoO2 (LCO), Li(NiMnCo)O2 (NMC), and / or LiNi 0.8 Co 0.15 Al 0.05 O2 (NCA)), spinel manganese oxides (such as LiMn2O4 (LMO) and / or LiMn 1.5 Ni 0.5 O4 (LMNO)) or olivine (e.g., LiFePO4). The positive electrode active material may include sulfur or a sulfur-containing material, such as lithium sulfide (Li2S), or other sulfur-based materials, or mixtures thereof. In some embodiments, the positive electrode film includes sulfur or a material containing a sulfur active material at a concentration of at least 50 wt%. In some embodiments, the positive electrode film containing sulfur or a material containing a sulfur active material has a capacity of at least 6 mAh / cm 2 In some embodiments, the positive electrode film containing sulfur or a material containing a sulfur active material has an area capacity of 1 g / cm 3 In some embodiments, the cathode film comprising sulfur or a material comprising a sulfur active material further comprises a binder. In some embodiments, the binder of the cathode film comprising sulfur or a material comprising a sulfur active material is selected from polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyethylene (PE), other thermoplastic materials, or any combination thereof.

[0044] The electrode film may include at least one active material combined with one or more carbon materials. The carbon material may be selected from, for example, a graphite material, graphite, a graphene-containing material, a hard carbon, a soft carbon, a carbon nanotube, a porous carbon, a conductive carbon, or a combination thereof. Activated carbon may be implemented, for example, activated carbon derived from a steam process or an acid / etching process. In some embodiments, the graphite material may be a surface-treated material. In some embodiments, the porous carbon may include activated carbon. In some embodiments, the porous carbon may include hierarchically structured carbon. In some embodiments, the porous carbon may include structured carbon nanotubes, structured carbon nanowires, and / or structured carbon nanosheets. In some embodiments, the porous carbon may include graphene sheets. In some embodiments, the porous carbon may be surface-treated carbon. In some embodiments, these carbon materials described herein may be similar to those described below with respect to Examples 1 and 2 and Figure 2 The processes shown in the drawings are described in more detail for different materials of conductive carbon additives and / or conductive carbon materials.

[0045] In some embodiments, the positive electrode film of a lithium ion battery or a hybrid energy storage device may include about 70 wt% to about 98 wt% of at least one active material, including about 70 wt% to about 92 wt%, or about 70 wt% to about 96 wt%. In some embodiments, the positive electrode film may include about or up to about 70 wt%, about or up to 90 wt%, about or up to about 92 wt%, about 94 wt%, about 95 wt%, about or up to about 96 wt%, or about or up to about 98 wt% of at least one active material, or any numerical range therebetween. In some embodiments, the positive electrode film of a lithium ion battery or a hybrid energy storage device may include about 40 wt% to about 60 wt% of at least one active material. In some embodiments, the positive electrode film may include up to about 10 wt% of a porous carbon material, including up to about 5 wt%, or about 1 wt% to about 5 wt%. In some embodiments, the positive electrode film may include about or up to about 10wt%, about or up to about 5wt%, about or up to about 1wt% or about or up to about 0.5wt% of porous carbon material, or any numerical range therebetween. In some embodiments, the positive electrode film includes up to about 5wt%, including about 1wt% to about 3wt% of conductive additives. In some embodiments, the positive electrode film includes about or up to about 10wt%, 5wt%, about or up to about 3wt% or about or up to 1wt% of conductive additives, or any numerical range therebetween. In some embodiments, the positive electrode film includes up to about 20wt% of a binder, for example, about 1.5wt% to 10wt%, about 1.5wt% to 5wt% or about 1.5wt% to 3wt%. In some embodiments, the positive electrode film includes about 1.5wt% to about 3wt% of a binder. In some embodiments, the positive electrode film contains about or up to about 20 wt %, about or up to about 15 wt %, about or up to about 10 wt %, about or up to about 5 wt %, about or up to about 3 wt %, about or up to about 1.5 wt %, or about or up to about 1 wt % of a binder, or any range of values ​​therebetween.

[0046] In some embodiments, the negative electrode film may include at least one active material, a binder and optional conductive additives and / or conductive materials. In some embodiments, the conductive additive may include a conductive carbon additive, such as carbon black. In some embodiments, the conductive material may include a conductive carbon material, such as carbon black. In some embodiments, the conductive carbon additive is a material of a different type and / or amount from the conductive carbon material. For example, in some embodiments, the conductive carbon additive and the conductive carbon material are different carbon black materials. In some embodiments, at least one active material of the negative electrode may include synthetic graphite, natural graphite, hard carbon, soft carbon, graphene, mesoporous carbon, silicon, silicon oxide (silicon oxide), tin, tin oxide (tin oxide), germanium, lithium titanate, a mixture or a composite material of the above materials. In some embodiments, the negative electrode film may include about 80wt% to about 98wt% of at least one active material, including about 80wt% to about 98wt%, or about 94wt% to about 97wt%. In some embodiments, the negative electrode film may include about 80wt%, about 85wt%, about 90wt%, about 92wt%, about 94wt%, about 95wt%, about 96wt%, about 97wt% or about 98wt% or about 99wt% of at least one active material, or any numerical range therebetween. In some embodiments, the negative electrode film contains up to about 5wt%, including about 1wt% to about 3wt% of conductive additives. In some embodiments, the negative electrode film contains about or up to about 5wt%, about or up to about 3wt%, about or up to about 1wt% or about or up to 0.5wt% of conductive additives, or any numerical range therebetween. In some embodiments, the negative electrode film contains up to about 20wt% of a binder, including about 1.5wt% to 10wt%, about 1.5wt% to 5wt% or about 3wt% to 5wt%. In some embodiments, the negative electrode film contains about 4wt% of a binder. In some embodiments, the negative electrode film comprises about or up to about 20wt%, about or up to about 15wt%, about or up to about 10wt%, about or up to about 5wt%, about or up to about 3wt%, about or up to about 1.5wt%, or about or up to about 1wt% of a binder, or any range of values ​​therebetween. In some embodiments, the negative electrode film may not include a conductive additive.

[0047] Some embodiments include electrode films, such as electrode films of negative and / or positive electrodes, with one or more active layers comprising polymer binder materials. Binders may include copolymers of polytetrafluoroethylene (PTFE), polyolefins, polyalkylenes (polyalkylene), polyethers, styrene-butadiene, polysiloxanes and polysiloxanes, branched polyethers, polyvinyl ethers, copolymers thereof and / or mixtures thereof. Binders may include cellulose, such as carboxymethyl cellulose (CMC). In some embodiments, polyolefins may include polyethylene (PE), polypropylene (PP), polyvinylidene fluoride (PVDF), copolymers thereof and / or mixtures thereof. For example, binders may include polyvinyl chloride, polyphenylene oxide (PPO), polyethylene block-poly (ethylene glycol), poly (ethylene oxide) (PEO), polyphenylene oxide (PPO), polyethylene-block-poly (ethylene glycol), polydimethylsiloxane (PDMS), polydimethylsiloxane-to-alkylmethylsiloxane, copolymers thereof and / or mixtures thereof. In some embodiments, binders may be thermoplastic. In some embodiments, binders include fibrillable polymers. In certain embodiments, the binder comprises, consists essentially of, or consists of a single fibrillable binder, such as PTFE.

[0048] In some embodiments, the binding agent may include PTFE and one or more optional additional binding agent components. In some embodiments, the binding agent may include one or more polyolefins and / or its copolymers, and PTFE. In some embodiments, the binding agent may include PTFE and may be one or more of a precursor, polysiloxane, a copolymer and / or its mixture of cellulose, polyolefins, polyethers, polyethers. The mixture of polymers may include the interpenetrating network of the above-mentioned polymers or copolymers.

[0049] Binder can comprise the polymer component of various suitable ratios.For example, PTFE can be the binder of up to about 98wt%, for example, about 20wt% to about 95wt%, about 20wt% to about 90wt%, including about 20wt% to about 80wt%, about 30wt%wt% to about 70wt%, about 30wt% to about 50wt% or about 50wt% to about 90wt%.In some embodiments, PTFE can be about or up to about 99 wt%, about or up to about 98 wt%, about or up to about 95 wt%, about or up to about 90 wt%, about or up to about 80 wt%, about or up to about 70 wt%, about or up to about 60 wt%, about or up to about 50 wt%, about or up to about 40 wt%, about or up to about 30 wt%, or about or up to about 20 wt% binder, or any numerical range therebetween.

[0050] In some embodiments, the electrode film mixture may include binder particles of a selected size. In some embodiments, the binder particles may be about 50 nm, about 100 nm, about 150 nm, about 200 nm, about 250 nm, about 300 nm, about 350 nm, about 400 nm, about 450 nm, about 500 nm, about 1 μm, about 2 μm, about 3 μm, about 4 μm, about 5 μm, about 10 μm, about 50 μm, about 100 μm, or any range of values ​​therebetween.

[0051] As used herein, a dry electrode manufacturing method may refer to a method in which a solvent is not used or substantially used to form a dry electrode film. For example, the components of the active layer or electrode film including a carbon material and a binder may include dry particles, be composed of them, or be substantially composed of them. The dry particles used to form the active layer or electrode film may be combined to provide a dry particle active layer mixture. In some embodiments, the active layer or electrode film may be formed by a dry particle active layer mixture so that the weight percentage of the components of the active layer or electrode film and the weight percentage of the components of the dry particle active layer mixture are substantially the same. In some embodiments, the active layer or electrode film formed by the dry particle active layer mixture using a dry manufacturing method may be free of or substantially free of any processing additives such as solvents and solvent residues resulting therefrom. In some embodiments, the resulting active layer or electrode film is a self-supporting film formed by a dry particle mixture using a dry method. In some embodiments, the resulting active layer or electrode film is a self-supporting film formed by a dry particle mixture using a dry method. In some embodiments, the resulting active layer or electrode film is a self-supporting film formed by a dry particle mixture using a dry method. The method for forming an active layer or electrode film may include fibrillating a fibrillable binder component so that the film contains a fibrillated binder. In other embodiments, a self-supporting active layer or electrode film can be formed in the absence of a current collector. In other embodiments, the active layer or electrode film can include a fibrillated polymer matrix so that the film is self-supporting. It is believed that a matrix, lattice or mesh of fibrils can be formed to provide the mechanical structure of the electrode film.

[0052] In some embodiments, the energy storage device electrode film, where the electrode film is a dry and / or self-supporting film, can provide a high electrode material loading or a high active material loading (which can be expressed as the mass of the electrode film per unit area of ​​the electrode film or current collector), with a loading of about 12 mg / cm 2 , about 13mg / cm 2 , about 14mg / cm 2 , about 15mg / cm 2 , about 16mg / cm 2 , about 17mg / cm 2 , about 18mg / cm 2 , about 19mg / cm 2 , about 20mg / cm 2, about 21mg / cm 2 , about 22mg / cm 2 , about 23mg / cm 2 , about 24mg / cm 2 , about 25mg / cm 2 , about 26mg / cm 2 , about 27mg / cm 2 , about 28mg / cm 2 , about 29mg / cm 2 , about 30mg / cm 2 , about 40mg / cm 2 , about 50mg / cm 2 , about 60mg / cm 2 , about 70mg / cm 2 , about 80mg / cm 2 , about 90mg / cm 2 or about 100mg / cm 2 , or any range of values ​​therebetween. In some embodiments, the energy storage device electrode film, wherein the electrode film is a dry and / or self-supporting film, can provide a high electrode material loading or a high active material loading (which can be expressed as the mass of the electrode film per unit area of ​​the electrode film or current collector), with a loading of at least about 12 mg / cm 2 , at least about 13 mg / cm 2 , at least about 14 mg / cm 2 , at least about 15 mg / cm 2 , at least about 16 mg / cm 2 , at least about 17 mg / cm 2 , at least about 18 mg / cm 2 , at least about 19 mg / cm 2 , at least about 20 mg / cm 2 , at least about 21 mg / cm 2 , at least about 22 mg / cm 2 , at least about 23 mg / cm 2 , at least about 24 mg / cm 2 , at least about 25 mg / cm 2 , at least about 26 mg / cm 2 , at least about 27 mg / cm 2 , at least about 28 mg / cm 2 , at least about 29 mg / cm 2 , at least about 30 mg / cm 2 , at least about 40 mg / cm 2 , at least about 50 mg / cm 2 , at least about 60 mg / cm 2, at least about 70 mg / cm 2 , at least about 80 mg / cm 2 , at least about 90 mg / cm 2 or at least about 100 mg / cm 2 , or any range of values ​​therebetween.

[0053] Electrode film can have the selected thickness suitable for some application.The thickness of electrode film provided herein can be greater than the thickness of the electrode film prepared by conventional method.In some embodiments, electrode film can have about or be greater than about 110 microns, about 115 microns, about 120 microns, about 130 microns, about 135 microns, about 150 microns, about 155 microns, about 160 microns, about 170 microns, about 200 microns, about 250 microns, about 260 microns, about 265 microns, about 270 microns, about 280 microns, about 290 microns, about 300 microns, about 350 microns, about 400 microns, about 450 microns, about 500 microns, about 750 microns, about 1mm or about 2mm or the thickness of any numerical range therebetween.Electrode film thickness can be selected to correspond to desired area capacity, specific capacity, area energy density, energy density or specific energy density.

[0054] In some embodiments, the electrode film porosity of the electrode film provided herein may be greater than the electrode film porosity of the electrode film prepared by conventional methods. In some embodiments, the electrode film porosity of the electrode film provided herein may be less than the electrode film porosity of the electrode film prepared by conventional methods. In some embodiments, the electrode film may have an electrode film porosity of about 10%, about 12%, about 14%, about 16%, about 18% or about 20% or any numerical range therebetween (which may be expressed as the volume percentage of the electrode film occupied by the pores). In some embodiments, the electrode film may have an electrode film porosity of at least about 10%, at least about 12%, at least about 14%, at least about 16%, at least about 18% or at least about 20% or any numerical range therebetween (which may be expressed as the volume percentage of the electrode film occupied by the pores). In some embodiments, the electrode membrane may have an electrode membrane porosity (which may be expressed as the percentage of the volume of the electrode membrane occupied by pores) of up to about 10%, up to about 12%, up to about 14%, up to about 16%, up to about 18%, or up to about 20%, or any range of values ​​therebetween.

[0055] In some embodiments, the electrode film density of the electrode film provided herein may be less than the electrode film density of the electrode film prepared by conventional methods. In some embodiments, the electrode film density of the electrode film provided herein may be greater than the electrode film density of the electrode film prepared by conventional methods. In some embodiments, the electrode film may have a density of about 0.8 g / cm 3 , 1.0g / cm3 , 1.4g / cm 3 , about 1.5g / cm 3 , about 1.6g / cm 3 , about 1.7g / cm 3 , about 1.8g / cm 3 , about 1.9g / cm 3 , about 2.0g / cm 3 , about 2.5g / cm 3 , about 3.0g / cm 3 , about 3.3g / cm 3 , about 3.4g / cm 3 , about 3.5g / cm 3 , about 3.6g / cm 3 , about 3.7g / cm 3 or about 3.8g / cm 3 Or any range of values ​​therebetween. In some embodiments, the electrode film may have a density of up to about 0.8 g / cm 3 , 1.0g / cm 3 , 1.4g / cm 3 , up to about 1.5g / cm 3 , up to about 1.6g / cm 3 , up to about 1.7g / cm 3 , up to about 1.8g / cm 3 , up to about 1.9g / cm 3 or up to about 2.0 g / cm 3 Or any range of values ​​therebetween. In some embodiments, the electrode film may have a density of at least about 0.8 g / cm 3 , 1.0g / cm 3 , 1.4g / cm 3 , at least about 1.5 g / cm 3 , at least about 1.6 g / cm 3 , at least about 1.7 g / cm 3 , at least about 1.8 g / cm 3 , at least about 1.9 g / cm 3 , at least about 2.0g / cm 3 , at least about 2.5g / cm 3 , at least about 3.0g / cm 3 , at least about 3.3g / cm 3 , at least about 3.4g / cm 3 or at least about 3.5 g / cm 3 or any range of densities therebetween.

[0056] In some embodiments, the energy storage device electrode film, wherein the electrode film is a dry and / or self-supporting film, can provide about or at least about 3.5 mAh / cm 2 , about 3.8mAh / cm 2 , about 4mAh / cm 2 , about 4.3mAh / cm 2 , about 4.5mAh / cm 2 , about 4.8mAh / cm 2 , about 5mAh / cm 2 , about 5.5mAh / cm 2 , about 6mAh / cm 2 , about 6.5mAh / cm 2 , about 6.6mAh / cm 2 , about 7mAh / cm 2 , about 7.5mAh / cm 2 , about 8mAh / cm 2 or about 10mAh / cm 2 , or an area capacity (which can be expressed as the capacity per unit area of ​​the electrode film or current collector) of any range of values ​​therebetween. In other embodiments, the energy storage device electrode film, wherein the electrode film is a dry and / or self-supporting film, can provide at least about 8 mAh / cm 2 , for example about 8 mAh / cm 2 , about 10mAh / cm 2 , about 12mAh / cm 2 , about 14mAh / cm 2 , about 16mAh / cm 2 , about 18mAh / cm 2 , about 20mAh / cm 2 Or an area capacity of any range of values ​​therebetween (which can be expressed as the capacity per unit area of ​​the electrode film or current collector). In some embodiments, the area capacity is the charge capacity. In other embodiments, the area capacity is the discharge capacity.

[0057] In some embodiments, a dry and / or self-supporting graphite battery negative electrode film can provide about 3.5 mAh / cm 2 , about 4mAh / cm 2 , about 4.5mAh / cm 2 , about 5mAh / cm 2 , about 5.5mAh / cm 2 , about 6mAh / cm 2 , about 6.5mAh / cm 2 , about 7mAh / cm 2 , about 7.5mAh / cm 2, about 8mAh / cm 2 , about 8.5mAh / cm 2 , about 9mAh / cm 2 , about 10mAh / cm 2 Or any range of values ​​therebetween. In some embodiments, the area capacity is the charge capacity. In other embodiments, the area capacity is the discharge capacity.

[0058] In some embodiments, the energy storage device electrode film wherein the electrode film is a dry and / or self-supporting film can provide a specific capacity (which can be expressed as the capacity per unit mass of the electrode film or current collector) of about 150 mAh / g, about 160 mAh / g, about 170 mAh / g, about 175 mAh / g, about 176 mAh / g, about 177 mAh / g, about 179 mAh / g, about 180 mAh / g, about 185 mAh / g, about 190 mAh / g, about 196 mAh / g, about 200 mAh / g, about 250 mAh / g, about 300 mAh / g, about 350 mAh / g, about 354 mAh / g, or about 400 mAh / g, or any range of values ​​therebetween. In other embodiments, the energy storage device electrode film wherein the electrode film is a dry and / or self-supporting film can provide a specific capacity (which can be expressed as the capacity per unit mass of the electrode film or current collector) of at least about 175 mAh / g or at least about 250 mAh / g, or any range of values ​​therebetween. In some embodiments, the specific capacity is the charge capacity. In other embodiments, the specific capacity is the discharge capacity. In some embodiments, the electrode can be a negative electrode and / or a positive electrode. In some embodiments, the specific capacity can be the first charge and / or discharge capacity. In other embodiments, the specific capacity can be the charge and / or discharge capacity measured after the first charge and / or discharge.

[0059] In some embodiments, the self-supporting dry electrode film described herein can advantageously exhibit improved performance relative to a typical electrode film. The performance can be, for example, tensile strength, elasticity (elongation), bendability, coulombic efficiency, capacity, or conductivity. In some embodiments, the electrode film of the energy storage device in which the electrode film is a dry and / or self-supporting film can provide about or at least about 85%, 86%, 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94% or about 95%, or any numerical range therebetween, such as 90.1%, 90.5% and 91.9%, or any numerical range therebetween Coulombic efficiency (which can be expressed as a percentage of discharge capacity divided by charge capacity).

[0060] In some embodiments, an energy storage device electrode film or electrode comprising a dry and / or self-supporting film wherein the electrode film is a dry and / or self-supporting film or electrode can provide a charge capacity retention percentage (which can be represented by the discharge capacity at a given rate divided by the discharge capacity measured at C / 10) of about or at least about 10%, about or at least about 20%, about or at least about 30%, about or at least about 40%, about or at least about 50%, about or at least about 60%, about or at least about 70%, about or at least about 80%, about or at least about 90%, about or at least about 98%, about or at least about 99%, about or at least about 99.9%, or about or at least about 100%, or any range of values ​​therebetween. In some embodiments, the discharge rate for the charge capacity retention percentage is about or at least about C / 10, C / 5, C / 3, C / 2, 1C, 1.5C, or 2C, or any value therebetween.

[0061] In some embodiments, the energy storage device electrode film or electrode comprising a dry and / or self-supporting film wherein the electrode film is a dry and / or self-supporting film or electrode can provide a charge capacity production percentage (which can be represented by the charge capacity measured at a given constant current rate divided by the discharge capacity measured at C / 10) of about or at least about 10%, about or at least about 20%, about or at least about 30%, about or at least about 40%, about or at least about 50%, about or at least about 60%, about or at least about 70%, about or at least about 80%, about or at least about 90%, about or at least about 98%, about or at least about 99%, about or at least about 99.9%, or about or at least about 100%, or any range of values ​​therebetween. In some embodiments, the charge rate for the charge capacity production percentage is or is at least C / 10, C / 5, C / 3, C / 2, 1C, 1.5C, or 2C, or any value therebetween.

[0062] In some embodiments, the electrode membrane of an energy storage device in which the electrode membrane is a dry and / or self-supporting membrane can provide a specific energy density or a gravimetric energy density (which can be expressed as energy per unit mass of electrode membrane) of about 200Wh / kg, about 210Wh / kg, about 220Wh / kg, about 230Wh / kg, about 240Wh / kg, about 250Wh / kg, about 260Wh / kg, about 270Wh / kg, about 280Wh / kg, about 290Wh / kg, about 300Wh / kg, about 400Wh / kg, about 500Wh / kg, about 600Wh / kg, about 650Wh / kg, about 700Wh / kg, about 750Wh / kg, about 800Wh / kg, about 825Wh / kg, about 850Wh / kg or about 900Wh / kg, or any range of values ​​therebetween.

[0063] In some embodiments, the electrode membrane of an energy storage device in which the electrode membrane is a dry and / or free-standing membrane can provide an energy density or volumetric energy density (which can be expressed as energy per unit volume of the final or in-situ electrode membrane) of about 550Wh / L, about 600Wh / L, about 630Wh / L, about 650Wh / L, about 680Wh / L, about 700Wh / L, about 750Wh / L, about 850Wh / L, about 950Wh / L, about 1100Wh / L, about 1400Wh / L, about 1425Wh / L, about 1450Wh / L, about 1475Wh / L, about 1500Wh / L, about 1525Wh / L or about 1550Wh / L, or any range of values ​​therebetween.

[0064] In some embodiments, the self-supporting dry battery positive electrode can exhibit reduced ohmic resistance and / or improved voltage polarization characteristics compared to a wet battery positive electrode. In other embodiments, a lithium ion battery incorporating a self-supporting dry positive electrode can advantageously exhibit reduced ohmic resistance and / or improved voltage polarization characteristics compared to a lithium ion battery having a wet positive electrode and a wet negative electrode. In other embodiments, a lithium ion battery incorporating a self-supporting dry positive electrode can exhibit improved energy density and / or specific energy density compared to a lithium ion battery including a wet positive electrode.

[0065] In some embodiments, the aged self-supporting dry cell electrode may exhibit reduced ohmic resistance, improved voltage polarization characteristics, and / or improved capacity compared to the aged wet cell electrode. In some embodiments, the ohmic resistance reduction exhibited by the aged dry cell electrode is about 5 times, about 10 times, about 15 times, or about 20 times less than the ohmic resistance reduction in the similarly aged wet cell electrode, or any range of values ​​therebetween. In some embodiments, the voltage reduction exhibited by the aged dry cell electrode is about 1.5 times, about 2 times, about 3 times, or about 5 times less than the voltage reduction in the similarly aged wet cell electrode, or any range of values ​​therebetween. In some embodiments, the capacitance reduction exhibited by the aged dry cell electrode is about 1.5 times, about 2 times, about 3 times, or about 5 times less than the capacitance reduction in the similarly aged wet cell electrode, or any range of values ​​therebetween.

[0066] Pre-lithiation :

[0067] Pre-lithiation of an electrode can be able to compensate for lithium consumed during initial cycling of an electrochemical device, which is no longer available for subsequent cycling. A sacrificial pre-lithiation material can be incorporated into the electrode to compensate for the consumed lithium, such as in the formation of a solid electrolyte interphase (SEI) layer on the negative electrode during initial cycling.

[0068] The pre-lithiation material defined herein is a lithium-containing material that is oxidized to form free lithium ions and byproducts when the electrochemical device is cycled. The lithium ions can then be solvated by the electrolyte of the device. Therefore, the pre-lithiation material acts as a lithium source from within the electrode film and compensates for the lithium ions consumed during the first charging process of the electrochemical device. In some embodiments, the pre-lithiation material is a strong reducing agent. In some embodiments, the pre-lithiation material is lithium oxide. In some embodiments, the pre-lithiation material is lithium oxide (Li2O), lithium peroxide (Li2O2), Li2S, Li3N, LiN3, LiF, Li5FeO4, Li2NiO2, Li6CO4, Li2MnO3, or a mixture thereof. In some embodiments, the pre-lithiation material is Li2O2. It should be understood that the pre-lithiation material does not include elemental lithium metal, which is lithium metal with a zero oxidation state.

[0069] In addition to the lithiated electrode, the reaction of the pre-lithiated material may also produce beneficial byproducts. In some embodiments, the byproduct may be a gas. For example, the decomposition of lithium peroxide produces oxygen. The generation of gas from the pre-lithiated material within the electrode may beneficially increase the porosity of the electrode.

[0070] In some embodiments, the electrode film mixture may include a pre-lithiation material at about 0.5 wt%, about 1 wt%, about 1.5 wt%, about 2 wt%, about 3 wt%, about 4 wt%, about 5 wt%, about 6 wt%, about 7 wt%, about 8 wt%, about 9 wt%, or about 10 wt%, or any range of values ​​therebetween.

[0071] Figure 2200 is a process flow diagram illustrating an example of a method 200 for manufacturing an electrode film comprising a pre-lithiation material according to some embodiments. In box 202, a first mixture comprising a pre-lithiation material and a conductive carbon additive is formed by a mixing step. In some embodiments, the pre-lithiation material is lithium peroxide. In some embodiments, the conductive carbon additive is carbon black, as described herein. In some embodiments, the mixing shown in box 202 is performed without overheating the first mixture. In some embodiments, the mixing shown in box 202 is performed so that the temperature of the first mixture is at most or at most about 200°C, 150°C, 140°C, 130°C, 120°C, 110°C, 100°C, 90°C, 80°C, 70°C, 60°C, or 50°C, or any range of values ​​therebetween. In some embodiments, the mixing shown in box 202 is performed so that the temperature of the first mixture is less than or below about 200°C, 150°C, 140°C, 130°C, 120°C, 110°C, 100°C, 90°C, 80°C, 70°C, 60°C, or 50°C, or any numerical range therebetween. In some embodiments, the mixing shown in box 202 is performed by blending. In some embodiments, the weight ratio of the pre-lithiation material to the conductive carbon additive is about 10:1, about 5:1, about 5:2, about 5:3, about 5:4, or about 1:1, or any numerical range therebetween. In some embodiments, the pre-lithiation material and the conductive carbon additive are intimately mixed to evenly distribute the components throughout the first mixture. In some embodiments, the pre-lithiation material and the conductive carbon additive are mixed to create electrical contact between the primary particles of the pre-lithiation material and the conductive carbon additive.

[0072] In box 208, the first mixture of box 202 is mixed with an active material, a carbon material, and a conductive carbon material to form a second mixture. In some embodiments, the active material, the carbon material, and the conductive carbon material are first mixed to form another mixture before mixing with the first mixture of box 202. In some embodiments, the conductive carbon material is carbon black, as described herein. In some embodiments, no carbon material and / or conductive carbon material is used to form the second mixture in box 208. In some embodiments, the mixing shown in box 208 is performed by blending. In some embodiments, the mixing shown in box 208 is performed so that the temperature of the first mixture is at most or at most about 200°C, 150°C, 140°C, 130°C, 120°C, 110°C, 100°C, 90°C, 80°C, 70°C, 60°C, or 50°C, or any numerical range therebetween. In some embodiments, the mixing shown in box 208 is performed so that the temperature of the first mixture is less than or about 200°C, 150°C, 140°C, 130°C, 120°C, 110°C, 100°C, 90°C, 80°C, 70°C, 60°C, or 50°C, or any range of values ​​therebetween. In some embodiments, the first mixture, active material, carbon material, and conductive carbon material are intimately mixed to evenly distribute the components throughout the second mixture. In some embodiments, the mixing process of box 208 is used to destroy or modify particles of active material. In some embodiments, modified particles of active material are used to catalyze the reaction of pre-lithiation material during the initial cycle of the electrochemical device.

[0073] In some embodiments, the mixing steps of blocks 202 and 208 can utilize a continuous mixing process. In such embodiments, the duration of blending and / or grinding can be inversely proportional to the feed rate. Typically, the feed rate depends on the grinding machine and can be adjusted based on the machine operating parameters according to the guidance provided herein. In other embodiments, the duration of blending and / or grinding can be increased using equipment with larger channels. When using batch blending and / or grinding processes, the duration can be increased simply by blending and / or grinding for a longer time and / or with a higher RMM.

[0074] In box 210, an electrode membrane mixture is formed by adding a fibrillable binder to the second mixture of box 208. In some embodiments, the fibrillable binder and the second mixture can be closely mixed to evenly distribute the components throughout the electrode membrane mixture. In box 212, the fibrillable binder in the electrode membrane mixture can be fibrillated to form fibrils from the binder material. The fibrillation process can be carried out at a reduced speed and / or an increased process pressure. The reduced speed and / or increased process pressure can promote increased fibril formation, so that a reduced amount of binder material can be used to form an electrode membrane with a desired resistance to tensile, shear, compression and / or torsional stress. As described herein, in some embodiments, the fibrillation process can be a mechanical shear process, for example, including blending and / or grinding processes, and in some embodiments, high shear processes such as jet grinding. In some embodiments, the speed at which the particles of the electrode membrane mixture circulate through the mixer and / or grinder can be reduced during the fibrillation process. In some embodiments, the process pressure in the mixer and / or grinder during the fibrillation process can be increased. In some embodiments, the adding step of box 210 and the fibrillating step of box 212 can be one or substantially one continuous step. The reduced speed and / or increased processing pressure can allow the manufacture of an electrode film with sufficiently high strength, such as a self-supporting electrode film, by a single higher pressure calendaring process (in a single step) or by multiple calendaring steps (e.g., unwinding the film after the initial calendaring step and then re-calendering one or more times).

[0075] In box 214, the electrode film mixture can be calendered in a calender device to form a self-supporting fibrillated electrode film. Calendering equipment is well known in the art and generally includes a pair of calendering rollers (with a mechanical fixed gap or a hydraulic or pneumatic pressure fixed gap), between which a raw material such as an electrode film mixture is fed to form an electrode film. In some embodiments, the electrode film can be formed in a first calendering step without an additional calendering step to form a film of a desired minimum thickness, as further described herein. In some embodiments, the calendered mixture forms a self-supporting dry particle film that is free of or substantially free of any liquid, solvent, and residues produced therefrom. In some embodiments, the electrode film is a negative electrode film. In some embodiments, the electrode film is a positive electrode film.

[0076] In some embodiments, the method 200 for making an electrode membrane is a dry process, in which no liquid or solvent is used and the raw materials listed are dry (e.g., one or more are dry powders) such that the resulting electrode membrane is free of or substantially free of any liquid, solvent, and resulting residue. In other wet electrode membrane methods, pre-lithiation materials may react with solvents such as PVDF and N-methyl-2-pyrrolidone (NMP), which may produce byproducts that may negatively affect the performance of the energy storage device. Therefore, the dry electrode method can provide a unique method for incorporating pre-lithiation materials into electrode membranes without exposure to solvents. In addition, polytetrafluoroethylene (PTFE) can be advantageously used because it can tolerate some acceptable pre-lithiation materials, such as lithium peroxide.

[0077] In the following specific examples, high energy density, high specific energy density, high thickness and / or high electrode film density battery electrodes are fabricated.

[0078] Example

[0079] Example 1

[0080] Example 1 describes the Figure 2 The electrode film was formed by the method described in . Lithium peroxide and SuperP carbon black were mixed in a Waring blender at a ratio of 5 to 2 in an Argon glove box at low setting for 10 minutes. Figure 3A Shown is a SEM image of lithium peroxide, demonstrating submicron primary particles. Figure 3B SEM images of lithium peroxide mixed with SuperP carbon black in a ratio of 5 to 2 are shown, indicating fine mixing and uniform distribution of the two components. Figure 2 As described, the first dry mixture is mixed to ensure the distribution of lithium peroxide and conductive carbon black, wherein the lithium peroxide and SuperP are blended at 3000 rpm in 30 second intermittent pulses with 30 second cooling in between. The above blending limits the temperature of the lithium peroxide and SuperP mixture to less than about 100°C to avoid excessive heating of the mixture during the blending process.

[0081] A pre-densified mixture of positive electrode active material NMC-622, activated carbon and Ketjen black is formed, and then the lithium peroxide / SuperP mixture is added thereto and blended for 5 minutes at low settings in an argon glove box. The blending part is to break up a small portion of the secondary particles of the positive electrode active material so that the smaller primary particles act as a catalyst for the oxygen evolution reaction of lithium peroxide during the initial cycle of the electrochemical device. Finally, a PTFE binder is added to the mixture and the binder is fibrillated to form an electrode membrane mixture.

[0082] The calendering of the electrode film mixture was carried out in a dry chamber to minimize the exposure of the powder to moisture to form a self-supporting electrode film. The self-supporting electrode film was then further calendered to a desired load and laminated onto an aluminum foil with an adhesive coating to form a positive electrode.

[0083] Figure 4 An image of such a laminated electrode immersed in water is shown. Figure 4 In the figure, oxygen bubbles can be seen on the surface of the laminated electrode, which indicates that the lithium peroxide present in the electrode is still active and has not decomposed. The reaction of lithium peroxide with water follows the following chemical equation:

[0084] 2Li2O2+2H2O→4LiOH+O2

[0085] Example 2

[0086] Figure 5 The electrochemical curves of the 2% lithium peroxide battery produced in Example 1 and the control battery without lithium peroxide are shown. Due to the electrochemical release of oxygen by lithium peroxide, the electrochemical cycle of the lithium ion positive electrode containing lithium peroxide shows an increased initial charge capacity, and when 2% lithium peroxide is added, an increase in charge capacity of about 10 mAh / g is observed, which is about 45% of the theoretical value of 22 mAh / g if all lithium peroxide is used. This additional charge capacity can be used to compensate for the irreversible capacity of the negative electrode during the formation cycle.

[0087] Although certain embodiments have been described, these embodiments are presented only by way of example and are not intended to limit the scope of the present disclosure. In fact, the novel methods and systems described herein can be implemented in a variety of other forms. In addition, various omissions, substitutions, and changes may be made to the systems and methods herein without departing from the spirit of the present disclosure. The attached claims and their equivalents are intended to cover such forms or modifications that fall within the scope and spirit of the present disclosure.

[0088] Features, materials, characteristics or groups described in conjunction with a particular aspect, embodiment or example are to be understood to be applicable to any other aspect, embodiment or example described in this section or elsewhere in this specification unless incompatible therewith. All features disclosed in this specification (including any accompanying claims, abstract and drawings) and / or all steps of any method or process disclosed may be combined in any combination, except combinations in which at least some of such features / or steps are mutually exclusive. Protection is not limited to the details of any foregoing embodiments. Protection extends to any novel feature or any novel combination of features disclosed in this specification (including any accompanying claims, abstract and drawings), or any novel step or any novel combination of steps of any method or process so disclosed.

[0089] In addition, certain features described in the present disclosure in the context of separate implementations may also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation may also be implemented separately in multiple implementations or in any suitable sub-combination. In addition, although features may be described above as functioning in certain combinations, in some cases, one or more features from a claimed combination may be removed from that combination, and the combination may be claimed as a sub-combination or a variation of a sub-combination.

[0090] In addition, although the operations may be depicted in the drawings or described in the specification in a particular order, it is not necessary to perform such operations in the particular order or sequential order shown, or it is not necessary to perform all operations to obtain the desired results. Other operations not depicted or described may be incorporated into the exemplary methods and processes. For example, one or more additional operations may be performed before, after, at the same time, or between any operations. In addition, in other implementations, the operations may be rearranged or reordered. It will be understood by those skilled in the art that in some embodiments, the actual steps taken in the illustrated and / or disclosed processes may be different from the steps shown in the figures. Depending on the implementation, some of the above steps may be removed and other steps may be added. In addition, the features and attributes of the specific embodiments disclosed above may be combined in different ways to form additional embodiments, all of which fall within the scope of the present disclosure. In addition, the separation of various system components in the above implementations should not be understood as requiring such separation in all implementations, and it should be understood that the components and systems described may generally be integrated together in a single product or packaged into multiple products. For example, any components for energy storage systems described herein may be provided separately, or integrated together (e.g., packaged together, or attached together) to form an energy storage system.

[0091] For the purposes of the present disclosure, certain aspects, advantages and novel features are described herein. According to any particular embodiment, not all of these advantages may be achieved. Thus, for example, those skilled in the art will recognize that the present disclosure may be implemented or practiced in a manner that achieves one advantage or a group of advantages taught herein without having to achieve other advantages taught or suggested herein.

[0092] The headings provided herein, if any, are for convenience only and do not necessarily affect the scope or meaning of the apparatus and methods disclosed herein.

[0093] The scope of the present disclosure is not intended to be limited by the specific disclosure of preferred embodiments in this section or other parts of this specification, and may be limited by the claims as presented in this section or elsewhere in this specification or in the future. The language of the claims is to be interpreted broadly based on the language used in the claims, and not limited to examples described in this specification or during the prosecution of the application, which examples should be interpreted as non-exclusive.

Claims

1. A dry electrode film for an energy storage device, comprising: Dry active materials; Dry binder; and An intercalated lithiated material is uniformly distributed throughout the dry active material and the dry binder, wherein the dry electrode film is self-supporting.

2. The dry electrode film according to claim 1, wherein the pre-lithiation material is selected from the group consisting of Li2O, Li2O2, Li2S, Li3N, LiN3, LiF, Li5FeO4, Li2NiO2, Li6CO4 and Li2MoO3 or a combination thereof.

3. The dry electrode film according to claim 1, wherein the intervening lithiation material is Li2O2.

4. The dry electrode film of claim 1, wherein the intervening lithiation material accounts for about 0.5-10 wt% of the dry electrode film. 5 . The dry electrode film according to claim 1 , wherein the dry active material is a dry positive electrode active material. 6 . The dry electrode film according to claim 5 , wherein the dry positive electrode active material comprises sulfur or a sulfur-containing material.

7. An energy storage device comprising the dry electrode film according to claim 1.

8. The energy storage device of claim 7, wherein the energy storage device is a battery.

9. A method for manufacturing a dry electrode film of an energy storage device, comprising: mixing an intervening lithiated material and a dry conductive carbon additive to form a first dry mixture; mixing the first dry mixture with a dry active material to form a second dry mixture; adding a dry fibrillable binder to the second dry mixture to form a dry electrode membrane mixture; and The dry binder in the dry electrode membrane mixture is fibrillated.

10. The method of claim 9, further comprising calendering the dry electrode film mixture to form a self-supporting dry electrode film.

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