METHOD FOR PREFORMING ANODE PARTICLES WITH CUSTOMIZED COMPOSITION OF SOLID ELECTROLYTE INTERMEDIATE PHASES

Abstract

A method for preforming anode particles for use in lithium-ion batteries is provided. The preformed anode particles carry a solid electrolyte with a composition that cannot be formed in situ within the battery. The method involves providing a dispersion of anode precursor particles and an additive not present in the battery in a liquid electrolyte solution. By applying a voltage or current across the dispersion, the solid electrolyte intermediate phase forms on the particles. These particles can then be used in an electrode of a lithium-ion battery.

Description

[0001] The government has rights to this invention pursuant to STRATEGIC PARTNERSHIP AGREEMENT NO. A21190 between UCHICAGO ARGONNE, LLC as operator of the ARGONNE NATIONAL LABORATORY, operating under PRIME CONTRACT NO. DE-AC02-06CH11357 for the U.S. Department of Energy, and GENERAL MOTORS LLC INTRODUCTION

[0002] The present disclosure relates to a method for forming particles useful in anodes in lithium ion batteries.

[0003] There is a need for advanced energy storage devices and systems to meet the energy and / or power requirements for a variety of products, including automotive products such as start-stop systems (e.g., 12V start-stop systems), battery-assisted systems, hybrid electric vehicles (“HEVs”), and electric vehicles (“EVs”).

[0004] Typical lithium-ion batteries comprise at least two electrodes and an electrolyte and / or separator. One of the two electrodes serves as the positive electrode (a cathode) and the other electrode serves as the negative electrode (an anode). A separator and / or electrolyte can be arranged between the negative and positive electrodes. The electrolyte is suitable for conducting lithium ions between the electrodes and, like the two electrodes, can be in solid and / or liquid form and / or a hybrid thereof. In the case of all-solid-state batteries, which contain solid-state electrodes and a solid-state electrolyte, the solid-state electrolyte can physically separate the electrodes, thus eliminating the need for a separate separator.

[0005] Conventional rechargeable lithium-ion batteries work by reversibly shunting lithium ions between the negative electrode and the positive electrode. For example, lithium ions can move from the positive electrode to the negative electrode when charging the battery and in the opposite direction when discharging the battery. Such lithium-ion batteries can reversibly supply power to an associated load device on demand. In particular, a load device can be supplied with electrical energy from the lithium-ion battery until the lithium content of the negative electrode is effectively depleted. The battery can then be recharged by flowing a suitable direct electrical current in the opposite direction between the electrodes.

[0006] During discharge, the negative electrode may contain a comparatively high concentration of lithium (e.g., intercalated lithium), which is oxidized to lithium ions and electrons. Lithium ions can migrate from the negative electrode to the positive electrode, e.g., through the ionically conductive electrolyte solution contained in the pores of an interposed porous separator. Simultaneously, the electrons traverse an external electrical circuit from the negative electrode to the positive electrode. These lithium ions can be incorporated into the positive electrode material through an electrochemical reduction reaction. The battery can be recharged or regenerated after partial or complete discharge of its available capacity by an external power source, thereby reversing the electrochemical reactions that occurred during discharge.

[0007] During the first cycle or the first few cycles of the battery, a solid electrolyte interphase (SEI) forms at the negative electrode due to electrolyte decomposition products. The SEI is ionically conductive but electron-insulating. The SEI is insoluble in the battery's electrolyte and can increase the battery's impedance and resistance. However, the SEI can also prevent further electrolyte decomposition. Thus, in lithium-ion batteries, the SEI can affect cyclability, rate capacity, irreversible capacity loss, and other factors. SUMMARY

[0008] In an exemplary embodiment, a method for preforming anode particles supporting a solid electrolyte interphase is disclosed, wherein the anode particles are for use in an anode of a lithium-ion battery, the lithium-ion battery comprising the anode, an anode current collector, a cathode, a cathode current collector, an optional separator, and a battery electrolyte. The method includes providing a dispersion in a vessel configured for electrochemical reactions, the dispersion containing anode precursor particles, a first liquid electrolyte solution, and an additive not included in the lithium-ion battery. A voltage or current is applied to the dispersion to form the anode particles supporting the solid electrolyte interphase. The anode particles supporting the solid electrolyte interphase can be recovered from the dispersion.

[0009] In addition to the one or more features described herein, the additive may be present in the dispersion before the voltage or current is applied. Alternatively, the additive may be added to the dispersion during the application of the voltage or current.

[0010] In addition to the one or more features described herein, an additional additive may be introduced into the dispersion after and during the application of the voltage or current to form a solid electrolyte interphase having a first layer of a first composition and a second layer of a second composition. The step of introducing an additional additive and applying the voltage after introducing the additional additive may be repeated with different additives.

[0011] In addition to the one or more features described herein, the anode particles may contain silicon, germanium, tin, bismuth, graphite, antimony, silicon oxide, or a combination of two or more of these materials.

[0012] In addition to one or more of the features described herein, the anode particles may have an average particle size of 50 nanometers to 100 micrometers.

[0013] In addition to the one or more features described herein, the solid electrolyte interphase may have a thickness of 1 to 100 nanometers.

[0014] In addition to the one or more features described herein, the first liquid electrolyte solution may contain a salt in a solvent. The salt may contain lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(oxalato)borate, lithium difluorooxalatoborate, or 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether. The solvent may contain ethylene carbonate, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, propylene carbonate, dimethyl sulfoxide, ethyl acetate, gamma-butyrolactone, 1,2-dimethoxyethane, or tetraethylene glycol dimethyl ether.

[0015] In addition to the one or more features described herein, the additive may contain a fluorinated carbonate, a vinylene carbonate, an alkoxysilane, or an alkylacrylamide.

[0016] In addition to the one or more features described herein, the dispersion may contain 1 to 25 weight percent of the anode particles and 0.001 to 10 weight percent of the additive, based on the total weight of the dispersion.

[0017] In addition to the one or more features described herein, the electrochemical reaction vessel may include a conductive shell as a current collector and an electrode comprising lithium metal.

[0018] In addition to one or more of the features described here, the voltage can be applied at a level of + / -10 to + / -7000 millivolts.

[0019] In addition to one or more of the features described herein, the current may be applied at a level of + / -0.01 to + / -10 milliamperes per square centimeter.

[0020] In addition to the one or more features described herein, the solid electrolyte interphase may have a homogeneous composition. Alternatively, the solid electrolyte interphase layer may have a composition that varies along a gradient from a surface of the anode particle to a surface of the solid electrolyte interphase.

[0021] In addition to the one or more features described herein, the solid electrolyte interphase may be inorganic, organic, or a combination thereof.

[0022] In addition to the one or more features described herein, the method may further comprise forming a second dispersion comprising the anode particles carrying the solid electrolyte interphase and a second liquid electrolyte solution different from the first liquid electrolyte solution, and applying a voltage or current across the dispersion to form a second layer of a solid electrolyte interphase on the anode particles.

[0023] In another exemplary embodiment, the method comprises forming a slurry comprising the anode particles carrying the solid electrolyte interphase as disclosed herein, a binder, a conductive component, and a solvent, applying the slurry to a current collector, drying, and optionally curing to form an anode.

[0024] In another exemplary embodiment, a lithium-ion battery is disclosed herein, comprising an anode disposed on an anode current collector, a cathode disposed on a cathode current collector, an optional separator disposed between the anode and the cathode, and a battery electrolyte. The anode contains anode particles with a preformed solid electrolyte interphase having a composition that could not be formed in situ in the battery.

[0025] The above features and advantages, as well as other features and advantages of the disclosure, will be readily apparent from the following detailed description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Further features, advantages and details are listed only as examples in the following detailed description, which refers to the drawings in which: Fig. 1 is a schematic representation of an example of an apparatus for performing certain embodiments of the method disclosed herein; Fig. 2 is a schematic representation of an example of an anode particle as may be produced by an example of the process disclosed herein having a preformed solid electrolyte interphase; Fig. 3 is a schematic representation of an example of an anode particle as may be produced by an example of the process disclosed herein with a preformed solid electrolyte interphase (bilayer SEI); and Fig. Figure 4 is a schematic diagram of an exemplary lithium-ion electrochemical battery. DETAILED DESCRIPTION

[0027] The following description is merely exemplary and is not intended to limit the present disclosure, its application, or uses. It should be understood that corresponding reference numerals indicate like or corresponding parts and features throughout the drawings.

[0028] The process described here allows the SEI to be preformed on anode particles before anode formation and battery assembly. Preforming the SEI can reduce capacity loss in the battery during initial cycling, increase the battery's first-cycle Coulombic efficiency, and / or reduce the loss of active lithium. Furthermore, the process enables the formation of SEI with compositions that could not be achieved with in-situ SEI formation during the battery's initial cycling.

[0029] According to an exemplary embodiment, the method disclosed herein provides for the preparation of anode particles having a preformed solid electrolyte interphase thereon.

[0030] The method comprises providing a solid-liquid dispersion in an electrochemical reaction vessel, the solid-liquid dispersion containing anode particles, a first liquid electrolyte solution, and an additive not present in the battery—in particular, not present in the battery electrolyte. The method comprises applying a voltage or current to the solid-liquid dispersion to form a layer of a solid electrolyte interphase around individual anode particles, the solid electrolyte interphase containing the additive or a reaction product of the additive. The method may comprise separating the anode particles supporting the solid electrolyte interphase layer from the dispersion. The voltage may be from + / -10 to + / -7000 or + / -500 to + / -3000 millivolts. The current density can be between + / -0.01 and + / -10 milliamperes per square centimeter.

[0031] For example, as in Fig. 1, a dispersion 100 of anode particles 110 with an electrolyte solution 112 is provided in a vessel 150. The vessel may contain a shell 152. The shell may contain a conductive material that may serve as a current collector. An electrode 154, such as a lithium ion battery, may be placed in the electrolyte solution 112, and a voltage or current may be applied. If lithiation of the anode particles 110 is desired, the electrode 154 may contain lithium. The electrolyte solution 112 contains an additive. The additive may, for example, be a component that is soluble in the electrolyte solution 112 or a component that is dispersed in the electrolyte solution 112. The additive comprises chemical components that are not found in a battery (including a battery electrolyte), such as the battery 20 or the electrolyte 30 of the battery 20 of Fig. 4. When a voltage or current is applied, a solid electrolyte interphase forms on the particle 110. The solid electrolyte interphase is a product of the electrochemical reaction between the electrolyte, the anode particle, and any additives present. The specific composition of the solid electrolyte interphase is influenced by these components as well as by the applied voltage or current. One of the electrodes may contain lithium. The presence of a lithium source enables pre-lithiation of the anode particles. The vessel may contain a mixer 156. Alternatively to the vessel 150 shown, which can operate in batch mode, a flow vessel could be used for continuous production.

[0032] When a voltage or current is applied to the dispersion 100, a solid electrolyte interphase 114 forms on the anode particles 110, forming coated particles 116, as shown in Fig. 2 shown.

[0033] After the formation of the coated particles 116 (i.e., the anode particles 110 carrying the SEI 114), the coated particles 116 can be separated from the dispersion 100 for further use. For example, the dispersion 100 can be filtered to separate the coated particles 116 from the electrolyte solution 112. Optionally, the coated particles 116 can be rinsed.

[0034] Another example is the use of a centrifuge to separate the coated particles 116.

[0035] The dispersion 100 may contain the anode particles 110 in an amount of 1 to 25, or 1.5 to 20, or 2 to 10 weight percent, based on the total weight of the dispersion. The dispersion 100 may contain the additive in the electrolyte solution 112 in an amount of 0.001 to 10, or 0.01 to 5, or 0.1 to 3 weight percent, based on the total weight of the dispersion. The electrolyte solution 112 may constitute the remainder of the dispersion 100.

[0036] The anode particles may, for example, contain silicon, germanium, tin, bismuth, graphite, antimony, silicon oxide, or a combination (e.g., an alloy) of two or more thereof. As another example, the anode particles may contain a lithium-based material, including lithium metal and / or lithium alloy. As another example, the anode particles may contain lithium-absorbing materials such as lithium titanium oxide (Li4TisO 12), one or more transition metals (such as tin (Sn)), one or more metal oxides (such as vanadium oxide (V2O5), tin oxide (SnO), titanium dioxide (TiO2)) and / or titanium niobium oxide Ti x Nb y O z where 0 ≤ x ≤ 2, 0 ≤ y ≤ 24, and 0 ≤ z ≤ 64).

[0037] The anode particles may be in the form of spheres or pellets. The spheres or pellets may have a regular shape, such as a substantially spherical shape, or they may have an irregular shape. The spheres or pellets may have an average particle size of 50 nanometers (nm) to 100 micrometers, 100 nm to 10 micrometers, or 200 nm to 5 micrometers. If the spheres or pellets are irregularly shaped, the aspect ratio of the largest to the smallest dimension may be less than 2:1. Alternatively, the anode particles may be in the form of platelets or nanowires. Such platelets may have a thickness of 20 nm to 10, up to 5, or up to 2 micrometers, with a dimension orthogonal to the thickness of 5 to 20 times the thickness. Such nanowires can have a length of 100 nm to 1 micrometer and an aspect ratio (length to cross-sectional dimension orthogonal to the length) of 2 to 100.The particle size can be determined using a particle size analyzer, e.g., dynamic light scattering or electron microscopic imaging.

[0038] The electrolyte solution 112 may contain an ionic compound, such as a salt, in a solvent. Examples of such ionic compounds that may be used include lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(oxalato)borate, lithium difluorooxalatoborate, and 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether. Examples of the solvent include ethylene carbonate, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, propylene carbonate, dimethyl sulfoxide, ethyl acetate, gamma-butyrolactone, 1,2-dimethoxyethane, and tetraethylene glycol dimethyl ether.

[0039] The additive is selected to provide a composition of the solid electrolyte interphase 114 on the anode particle 110 that cannot be achieved by in-situ formation of a solid electrolyte interphase during operation of a lithium-ion battery. The additive may be, for example, a fluorinated carbonate such as fluoroethylene carbonate or methyl (2,2,2-trifluoroethyl) carbonate, a vinylene carbonate, an alkoxysilane such as tetraethoxysilane or (2-cyanoethyl)triethoxysilane, or an alkylacrylamide such as dimethylacrylamide. More than one additive may be used. The additives may be added at different times. For example, a first additive may be present in the initial dispersion, while a second additive may be added at a later time.

[0040] The components of Dispersion 110 can be combined and stirred to ensure suspension of the anode particles while the voltage or current is applied.

[0041] By varying the applied voltage or current over time, by adjusting the time at which an additive is introduced, by using more than one additive, by varying the concentration of the additive(s), or by a combination thereof, the chemical composition of the solid electrolyte interphase can be controlled. For example, a solid electrolyte interphase can have a concentration gradient from the position adjacent to the anode particle to the outside of the solid electrolyte interphase. As another example, a two-layer solid electrolyte interphase can be formed, as in Fig. 3. The two-layer solid electrolyte interphase 114 has an inner layer 114i and an outer layer 114o on the anode particle 110, forming the coated particle 116.

[0042] For example, the additive can be added to the solid-liquid dispersion before the voltage is applied. As another example, the additive can be added to the solid-liquid dispersion after the initial application of the voltage and during the application of the voltage. As another example, an initial voltage is applied to the combination of anode particles and liquid electrolyte solution before adding the additive to the solid-liquid dispersion. As another example, an additional additive is introduced into the solid-liquid dispersion after the voltage is applied, and a voltage is applied after the additional additive is introduced. The process of adding an additional additive and applying the voltage after the additional additive is introduced can be repeated to further differentiate the chemistry in the outer portions of the solid-electrolyte interphase.If two clearly differentiated bilayers of the solid-electrolyte interphase are desired, the particles can be separated and rinsed after the formation of a first solid-liquid interphase and then reintroduced into a second electrolyte solution containing a different solvent, a different salt and / or a different additive.

[0043] Examples of inorganic solid electrolyte interphases 114 that can be obtained by the disclosed method include lithium carbonate (Li2CO3O), lithium fluoride (LiF), Li2O, and Li3N. Examples of organic solid electrolyte interphases 114 that can be obtained by the disclosed method include lithium alkyl carbonates, such as lithium ethylene decarbonate.

[0044] Batteries can be manufactured comprising anode particles with a preformed solid electrolyte interphase, as described herein. These batteries can then contain anode particles with a solid electrolyte interphase that could not be formed in situ within the battery. In particular, the battery can include an anode comprising anode particles with a preformed solid electrolyte interphase disposed on an anode current collector, a cathode disposed on a cathode current collector, an optional separator disposed between the anode and the cathode, and a battery electrolyte. The solid electrolyte interphase can have a composition that could not be formed in situ within the battery.

[0045] For example, Fig.4 is an exemplary schematic diagram of an electrochemical cell (also referred to as a battery) 20. The battery 20 includes a negative electrode (i.e., anode) 22 disposed on a current collector 32, a positive electrode (i.e., cathode) 24 disposed on a current collector 34, and a separator 26 disposed between the electrodes 22, 24. The separator 26 provides electrical isolation (i.e., prevents physical contact) between the electrodes 22, 24. The separator 26 also provides a path of minimum resistance for the internal passage of lithium ions and, in certain cases, related anions during cycling of the lithium ions. The battery includes an electrolyte 30, which is shown as being present in the separator 26. In certain aspects, the electrolyte may also be present in the anode 22 and the cathode 24.In certain variants, the separator 26 may be formed by a solid-state electrolyte 30. The anode current collector 32 and the cathode current collector 34 collect and transport free electrons to and from an external circuit 40. For example, an interruptible external circuit 40 and a load device 42 may connect the anode 22 (via the negative electrode current collector 32) and the cathode 24 (via the cathode current collector 34).

[0046] In the battery 20, the cathode 24 comprises a lithium-based positive electroactive material that may undergo lithium intercalation and deintercalation, an alloying and dealloying process, or a coating and stripping process while functioning as the positive terminal of the battery 20. In various aspects, the cathode 24 may be defined by a plurality of electroactive material particles (not shown). Such positive electroactive material particles may be arranged in one or more layers to define the three-dimensional structure of the cathode 24. In certain variations, as mentioned above, the cathode 24 may further comprise the electrolyte 30, e.g., a plurality of electrolyte particles (not shown).

[0047] In various aspects, the cathode 24 may be a layered oxide cathode, a spinel cathode, or a polyanion cathode. For example, layered oxide cathodes (e.g., rock salt layered oxides) comprise one or more lithium-based positive electroactive materials selected from LiNi x Mn y Co 1-x-y O2 (where 0 ≤ x ≤ 1 and 0 ≤ y ≤ 1), LiNi x Mn1- x O2 (where 0 ≤ x ≤ 1), Li 1+x MO2 (where M is one of Mn, Ni, Co, and Al and 0 ≤ x ≤ 1) (e.g. LiCoO2 (LCO), LiNiO2, LiMnO2, LiNi 0,5 Mn 0,5 O2, NMC111, NMC523, NMC622, NMC 721, NMC811, NCA). Spinel cathodes contain one or more positive electroactive lithium-based materials selected from LiMn2O4 and LiNi 0,5 Mn 1,5O4. Olivine-type cathodes contain one or more positive electroactive lithium-based materials such as LiV2(PO4)3, LiFePO4, LiCoPO4, and LiMnPO4. Tavorite cathodes contain, for example, LiVPO4F. Borate cathodes contain, for example, one or more of the elements LiFeBO3, LiCoBO3, and LiMnBO3. Silicate cathodes contain, for example, Li2FeSiO4, Li2MnSiO4, and LiMnSiO4F. In still further variations, the cathode 24 may contain one or more other positive electroactive materials, such as one or more of dilithium (2,5-dilithiooxy) terephthalate or polyimide. In various aspects, the positive electroactive material may optionally be coated (e.g., with LiNbO3 and / or Al2O3) and / or doped (e.g., with one or more of the elements magnesium (Mg), aluminum (Al), and manganese (Mn)).

[0048] The positive electroactive material of the cathode 24 may optionally be blended with one or more electrically conductive materials that provide an electron-conductive path and / or at least one polymeric binder material that improves the structural integrity of the cathode 24. For example, the positive electroactive material of the cathode 24 may optionally be blended with binders such as polytetrafluoroethylene (PTFE), sodium carboxymethylcellulose (CMC), styrene-butadiene rubber (SBR), polyvinylidene fluoride (PVDF), acrylonitrile-butadiene rubber (NBR), styrene-ethylene-butylene-styrene copolymer (SEBS), styrene-butadiene-styrene copolymer (SBS), lithium polyacrylate (LiPAA), sodium polyacrylate (NaPAA), sodium alginate, lithium alginate, ethylene-propylene-diene monomer (EPDM), and combinations thereof. Electrically conductive materials may contain carbon-based materials, nickel powder or other metal particles, or a conductive polymer.Carbon-based materials may include, for example, particles of carbon black, graphite, acetylene black (such as KETCHEN™ black or DENKA™ black), carbon fibers and nanotubes, graphene, and the like. Examples of a conductive polymer include polyaniline, polythiophene, polyacetylene, polypyrrole, and the like.

[0049] For example, the cathode 24 may comprise greater than or equal to about 50 wt.% to less than or equal to about 99 wt.%, and in certain aspects, optionally greater than or equal to about 50 wt.% to less than or equal to about 95 wt.% of the positive electroactive material, greater than or equal to about 0 wt.% to less than or equal to about 30 wt.%, and in certain aspects, optionally greater than or equal to about 2 wt.% to less than or equal to about 5 wt.% of one or more electrically conductive materials, and greater than or equal to about 0 wt.% to less than or equal to about 20 wt.%, and in certain aspects, optionally greater than or equal to about 2 wt.% to less than or equal to about 5 wt.% of one or more binders.

[0050] In battery 20, anode 22 may include the anode particles supporting the preformed solid electrolyte interphase described herein. Anode 22 may further include electrically conductive material such as carbon black, graphene, and / or carbon nanotubes. Anode 22 may further include a binder material such as polytetrafluoroethylene (PTFE), sodium carboxymethylcellulose (CMC), styrene-butadiene rubber (SBR), polyvinylidene fluoride (PVDF), acrylonitrile-butadiene rubber (NBR), styrene-ethylene-butylene-styrene copolymer (SEBS), styrene-butadiene-styrene copolymer (SBS), lithium polyacrylate (LiPAA), sodium polyacrylate (NaPAA), sodium alginate, lithium alginate, ethylene-propylene-diene monomer (EPDM), and combinations thereof.

[0051] The anode 22 may include greater than or equal to about 50 wt. % to less than or equal to about 99 wt. %, and in certain aspects optionally greater than or equal to about 50 wt. % to less than or equal to about 95 wt. % of the anode particles supporting the preformed solid electrolyte interphase, greater than or equal to about 0 wt. % to less than or equal to about 30 wt. % and in certain aspects optionally greater than or equal to about 5 wt. % to less than or equal to about 20 wt. % of one or more electrically conductive materials, and greater than or equal to about 0 wt. % to less than or equal to about 20 wt. % and in certain aspects optionally greater than or equal to about 5 wt. % to less than or equal to about 15 wt. % of one or more binders.

[0052] The battery electrolyte 30 may contain an ionic compound, such as a salt, optionally in a solvent. Examples of such ionic compounds that may be used include lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(oxalato)borate, lithium difluorooxalatoborate, or 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether. Examples of the solvent include ethylene carbonate, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, propylene carbonate, dimethyl sulfoxide, ethyl acetate, gamma-butyrolactone, 1,2-dimethoxyethane, and tetraethylene glycol dimethyl ether.

[0053] In an exemplary embodiment, the battery may contain a solid polymer electrolyte.

[0054] The separator 26 may contain polymers such as polypropylene or polyethylene, ceramics or polymer / ceramic composites.

[0055] In an exemplary embodiment, the battery may include a solid electrolyte / separator such as a ceramic, e.g., a lithium metal oxide, LISICON, Pervoskite, sulfide solid electrolyte, or garnet.

[0056] The terms "a" and "an" do not imply a limitation of quantity, but denote the presence of at least one of the mentioned items. The term "or" means "and / or" unless the context clearly indicates otherwise. Whenever "an aspect" is mentioned throughout the description, this means that a particular element (e.g., a feature, structure, step, or property) described in connection with the aspect is included in at least one of the aspects described herein and may or may not be present in other aspects. It is further understood that the described elements in the various aspects may be combined in any suitable way.

[0057] When an element such as a layer, film, region, or substrate is described as lying "on" another element, it may lie directly on top of the other element, or there may be intervening elements. In contrast, when an element is described as lying "directly on" another element, there are no intervening elements.

[0058] Unless otherwise indicated herein, all examination standards are the most recent standard in effect as of the filing date of this application or, if priority is claimed, as of the filing date of the earliest priority application in which the examination standard appears.

[0059] Unless otherwise defined, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0060] While the above disclosure has been described with reference to exemplary embodiments, it will be appreciated by those skilled in the art that various changes may be made and equivalents may be substituted for elements without departing from the scope thereof. Furthermore, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure without departing from the essential scope thereof. Therefore, the present disclosure is not intended to be limited to the particular embodiments disclosed, but is intended to include all embodiments falling within its scope.

Claims

[1] A method for preforming anode particles carrying a solid electrolyte interphase, the anode particles being for use in an anode of a lithium-ion battery, the lithium-ion battery comprising the anode, an anode current collector, a cathode, a cathode current collector, an optional separator, and a battery electrolyte, the method comprising: Providing a dispersion in a vessel configured for electrochemical reactions, the dispersion comprising anode precursor particles and a first liquid electrolyte solution, and the dispersion containing an additive that is not present in the lithium-ion battery, Applying a voltage across the dispersion or applying a current across the dispersion to form the anode particles carrying the solid electrolyte interphase, and Recovering the anode particles carrying the solid electrolyte interphase from the dispersion. [2] The method of claim 1, wherein the additive is present in the dispersion prior to application of the voltage or current. [3] The method of claim 1, wherein the additive is added to the dispersion during application of the voltage or current. [4] The method of claim 2, wherein after application of the voltage or current and during application of the voltage or current, an additional additive is introduced into the dispersion to form a solid electrolyte interphase having a first layer of a first composition and a second layer of a second composition. [5] The method of claim 4, further comprising repeating the step of introducing an additional additive and applying the voltage after introducing the additional additive. [6] The method of claim 1, wherein the first liquid electrolyte solution comprises a salt in a solvent, wherein the salt comprises lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(oxalato)borate, lithium difluorooxalatoborate or 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether and / or the solvent comprises ethylene carbonate, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, propylene carbonate, dimethyl sulfoxide, ethyl acetate, gamma-butyrolactone, 1,2-dimethoxyethane or tetraethylene glycol dimethyl ether. [7] The process of claim 1, wherein the additive comprises a fluorinated carbonate, a vinylene carbonate, an alkoxysilane or an alkylacrylamide. [8] The process of claim 1, wherein the dispersion comprises 1 to 25 weight percent of the anode particles and 0.001 to 10 weight percent of the additive, based on the total weight of the dispersion. [9] The method of claim 1, further comprising forming a second dispersion comprising the anode particles carrying the solid electrolyte interphase and a second liquid electrolyte solution different from the first liquid electrolyte solution, and applying a voltage or current across the dispersion to form a second layer of solid electrolyte interphase on the anode particles. [10] A lithium-ion battery comprising an anode disposed on an anode current collector, a cathode disposed on a cathode current collector, an optional separator disposed between the anode and the cathode, and a battery electrolyte, wherein the anode comprises anode particles having a preformed solid electrolyte interphase with a composition that could not be formed in situ in the lithium-ion battery.

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