Electrochemical energy-storage cells having high-silicon-content anodes, and related devices and methods

Abstract

: Silicon-containing anode-active materials with sulfonamide-functional-group electrolyte solvents. An electrochemical energy-storage cell includes an anode, a cathode, a porous separator disposed between the anode and the cathode, a container, and an electrolyte. The anode includes a current collector and an anode-active material in electrical communication with the current collector, wherein the anode-active material comprises silicon. The electrolyte is in contact with the anode- active material and the cathode and permeates the porous separator, and includes an alkali-metal salt and a solvent system comprising at least one solvent, wherein at least one solvent comprises a sulfonamide functional group. In some embodiments, the solvent system comprises at least one carbonate solvent and N,N-dimethyl sulfamoyl fluoride (DMSF). In some embodiments, the electrolyte forms a stabilized interphase on the anode, wherein the stabilized interphase comprises inorganic species including LiF.

Description

SES184 ELECTROCHEMICAL ENERGY- STORAGE CELLS HAVING HIGH-SILICON-CONTENT ANODES, AND RELATED DEVICES AND METHODS RELATED APPLICATION DATA

[0001] This application claims the benefit of priority of U.S. Provisional Patent Application Serial No. 63 / 790,164, filed on April 17, 2025, and titled “Electrochemical Energy- Storage Cells Having High-Silicon-Content Anodes, and Related Devices and Methods”, which is incorporated by reference herein in its entirety.FIELD OF THE INVENTION

[0002] The present invention generally relates to the field of electrochemical energy-storage cells. In particular, the present invention is directed to electrochemical energy-storage cells having high-silicon-content anodes, and related devices and methods.BACKGROUND

[0003] In recent years, demand for high-performance batteries has surged, driven by the rapid growth of portable electronic devices, electric vehicles, and renewable energy storage systems. Traditional lithium-ion batteries, which have been the cornerstone of energy storage-technology, are facing limitations in terms of energy density, safety, and longevity. The anode-active material, typically made of graphite, is one of the critical components that determine a battery’s overall performance. However, graphite anodes have reached their theoretical capacity limits, prompting researchers to explore silicon as an alternative anode-active material due to its high theoretical capacity.

[0004] Anodes utilizing silicon as the anode-active material, while promising, present significant challenges, including volume expansion of the silicon during lithiation and delithiation, which leads to mechanical degradation and poor cycling stability. To address these issues, development of advanced electrolytes that can effectively stabilize the surface of the silicon is crucial. Electrolytes play a vital role in forming a stable solid-electrolyte interphase (SEI) layer, which is essential for maintaining battery performance over extended cycles. The search for novel electrolyte formulations that can enhance the stability and performance of silicon anodes is a key area of research in the quest for next-generation batteries with higher energy densities and improved safety profiles.1 Attorney Docket No. 17468-184WOU1BRIEF DESCRIPTION OF THE DRAWINGS:

[0005] FIG. 1 is a graph showing discharge capacity over 300 cycles for a first new electrolyte according to aspects of the present disclosure and a first control carbonate electrolyte, showing the first new electrolyte maintaining higher capacity;

[0006] FIG. 2 is a graph of cycle life versus cycle number for a second new electrolyte according to aspects of the present disclosure and a second control carbonate electrolyte, showing the second new electrolyte providing longer cycle life;

[0007] FIG. 3A is a graph of discharge capacity at 25°C and at -20°C for the second control carbonate electrolyte, a third new electrolyte according to aspects of the present disclosure, and a fourth new electrolyte according to aspects of the present disclosure, showing the third new electrolyte and the fourth new electrolyte providing higher low-temperature discharge capacity;

[0008] FIG. 3B is a graph of capacity retention at -20°C for the second control carbonate electrolyte, the third new electrolyte, and the fourth new electrolyte, showing the third new electrolyte and the fourth new electrolyte providing higher capacity retention at -20°C;

[0009] FIG. 3C is a graph of cycle life versus cycle number for the second control carbonate electrolyte, the third new electrolyte, and the fourth new electrolyte, showing the third new electrolyte and the fourth new electrolyte providing longer cycle life;

[0010] FIG. 4A is a graph of average remaining capacity at 2 weeks and at 4 weeks of storage at 60°C for a third control carbonate electrolyte, a fifth new electrolyte according to aspects of the present disclosure, and a sixth new electrolyte according to aspects of the present disclosure, showing the fifth new electrolyte and the sixth new electrolyte providing higher remaining capacity after high-temperature storage;

[0011] FIG. 4B is a graph of average recovered capacity at 2 weeks and at 4 weeks of storage at 60°C for the third control carbonate electrolyte, the fifth new electrolyte, and the sixth new electrolyte, showing the fifth new electrolyte and the sixth new electrolyte providing higher recovered capacity after high-temperature storage;

[0012] FIG. 4C is a graph of direct current internal resistance (DCIR) at 2 weeks and at 4 weeks of storage at 60°C for the third control carbonate electrolyte, the fifth new electrolyte, and the sixth2 Atorney Docket No. 17468-184WOU1new electrolyte, showing the fifth new electrolyte and the sixth new electrolyte exhibiting lower DCIR growth after high-temperature storage;

[0013] FIG. 5 illustrates a simplified electrochemical energy-storage cell made in accordance with aspects of the present disclosure; and

[0014] FIG. 6 illustrates, in a flowchart, a method of enhancing batery performance using an electrolyte according to aspects of the present disclosure.SUMMARY OF THE DISCLOSURE

[0015] In one implementation, the present disclosure is directed to an electrochemical energystorage cell, which includes an anode that includes a current collector and an anode-active material in electrical communication with the current collector, wherein the anode-active material comprises silicon material; a cathode; a porous separator disposed between the anode and the cathode, the porous separator electrically insulating the anode and the cathode relative to one another; a container that contains the anode, the cathode, and the porous separator; and an electrolyte in contact with the anode-active material and the cathode and permeating the porous separator. The electrolyte includes an alkali-metal salt; and a solvent system comprising at least one solvent, wherein at least one solvent comprises a sulfonamide functional group.

[0016] In another implementation, the present disclosure is directed to a method of making an electrochemical energy-storage cell. The method includes placing an anode in a container, wherein the anode includes a current collector and an anode-active material in electrical communication with the current collector, and the anode-active material comprises silicon material; placing a porous separator in the container on top of the anode; placing a cathode in the container on top of the porous separator, wherein the porous separator electrically insulates the anode and the cathode; adding an electrolyte to the container, wherein the electrolyte is in contact with the anode-active material and the cathode and permeates the porous separator. The electrolyte includes an alkali-metal salt; and a solvent system comprising at least one solvent having a sulfonamide functional group; and sealing the container.DETAILED DESCRIPTION

[0017] The entire contents of the appended claims are incorporated into this Detailed Description section as if originally presented herein.3 Atorney Docket No. 17468-184WOU1

[0018] As used herein, the term “about” when used with a corresponding numeric value refers to ±20% of the numeric value, typically ±10% of the numeric value, often ±5% of the numeric value, and most often ±2% of the numeric value. In some embodiments, the term “about” can mean the numeric value itself. In certain embodiments, where applicable, the term “about” indicates the designated value(s) ± one standard deviation of that / those value(s).

[0019] As used herein, the term “silicon material” means pure silicon (such as, but not limited to, micro-size pure silicon or nano-size pure silicon), porous silicon, silicon formed from chemical vapor deposition, or any engineered silicon alloy (such as, but not limited to, silicon carbide or silicon oxide).

[0020] In some aspects, the present disclosure is directed to electrochemical energy-storage cells comprising an electrolyte having at least one solvent comprising a sulfonamide functional group. Having at least one solvent comprising a sulfonamide functional group can replace some or all of the functionality conventionally provided by carbonates and additives in conventional lithium-ion bateries (e.g., ethylene carbonate (EC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), propylene carbonate (PC), dimethyl carbonate (DMC), vinylene carbonate (VC), and fluoroethylene carbonate (FEC)). For example, the sulfonamide functional group can provide bulk electrolyte properties (e.g., ionic conductivity, electrochemical stability, viscosity, etc.); compatibility with the cathode, anode, and separator; and constituents for the SEI layer, whether used alone or in combination with one or more additional solvents, cosolvents, additives, or diluents. In some embodiments, the electrolyte is substantially free of carbonate solvents. In some embodiments, the electrolyte comprises one or more carbonate solvents together with the solvent having the sulfonamide functional group. In some embodiments, the one or more carbonate solvents comprise one or more of ethylene carbonate (EC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), dimethyl carbonate (DMC), or propylene carbonate (PC). In some embodiments, the one or more carbonate solvents are preferred components of the electrolyte because carbonate solvents are widely used in lithium-ion batery electrolytes and provide relatively high dielectric constants and good salt solubility. In some embodiments, the one or more carbonate solvents provide good bulk ionic conductivity, while the solvent having the sulfonamide functional group provides constituents for forming a passivation layer on a silicon-containing anode.

[0021] In some embodiments, the sulfonamide functional group comprises elements such as fluorine, sulfur, oxygen, and / or nitrogen. Fluorine, sulfur, oxygen, and / or nitrogen-containing4 Atorney Docket No. 17468-184WOU1sulfonamide solvents can be decomposed to generate inorganic-rich SEI passivation layers composed of LiF, LiiO, LiiS, SOX, and / or LisN, which are inorganic species having low electronic conductivity, thin layer thickness, and strong mechanical strength, thus resulting in quick insulating passivation functionality and a stable and dense SEI passivation layer to reduce continuous side reactions and enhance cycle life, capacity, and middle discharge voltage. Middle discharge voltage is the average discharge voltage calculated in an entire discharge step from the beginning to the end, so a higher middle discharge voltage is beneficial because it indicates lower polarization and higher energy density.

[0022] In some embodiments, electrochemical energy-storage cells according to the present disclosure comprise a high-capacity anode, such as a high-silicon-content anode. High-capacity anodes may have a capacity ranging from about 450 mAh / g to 3,000 mAh / g. High-silicon-content anodes may comprise an anode-active material that comprises at least about 30 wt% silicon material. In other embodiments, electrochemical energy-storage cells according to the present disclosure comprise an anode having an anode-active material that is at least about 0.5 wt% silicon material. In some embodiments, the anode-active material comprises at least about 5 wt% silicon material. In some embodiments, the anode-active material comprises silicon material and graphite. Anodes may also comprise graphite active materials, binders (such as carboxymethyl cellulose (CMC), styrenebutadiene rubber (SBR), and poly(acrylic acid) (PAA)), and / or conductive agents. When contemplating the weight of an entire anode (excluding its current collector) and not just the anodeactive material, anodes according to aspects of the present disclosure may comprise about 0.5 wt% to about 98 wt% silicon material.

[0023] Electrolytes comprising a sulfonamide functional group effectively passivate the surface of anodes comprising silicon and result in extensions of cycling life. Electrolytes comprising a sulfonamide functional group also promote the formation of low-resistance passivation layers to increase discharge capacity and middle discharge voltage, leading to a rise in battery energy density. In embodiments wherein an electrochemical energy-storage cell comprises both (1) an electrolyte comprising a sulfonamide functional group and (2) an anode comprising an anode-active material comprising at least about 30 wt% silicon material, total battery energy density is further boosted. In some embodiments wherein the electrolyte further comprises one or more carbonate solvents together with N,N-dimethyl sulfamoyl fluoride (DMSF), the one or more carbonate solvents provide bulk ionic conductivity due to their relatively high dielectric constants and salt solubility, while the DMSF forms an inorganic-rich solid electrolyte interphase (SEI) layer that better passivates the 5 Attorney Docket No. 17468-184WOU1surface of the silicon-containing anode. In some embodiments, combining DMSF and one or more carbonate solvents provides both good ionic conductivity and improved silicon-anode surface passivation.

[0024] Electrolytes comprising a sulfonamide functional group also benefit from reduced flammability when compared to traditional state-of-the-art commercial carbonate-based electrolytes — this is true both in embodiments wherein the anode-active material comprises 100 wt% silicon material and in embodiments wherein the anode-active material comprises a combination of silicon material and graphite. In particular, electrolytes comprising a sulfonamide functional group can be used to reduce and suppress gassing during high temperature storage, such as storage at 60°C to 70°C. In some embodiments, the electrochemical energy-storage cell is stored at a temperature of at least 50°C. Reduced gassing leads to improved battery performance and longevity, even under challenging thermal conditions. In sum, certain electrochemical energy-storage cells, such as cells having high-silicon-content anodes, comprising electrolytes according to aspects of the present disclosure overcome problems in conventional lithium-ion batteries, which lead to improved cycling stability, increased energy density, and increased safety by reducing flammability.

[0025] Moreover, while conventional anodes comprising silicon have been limited to having an anode-active material comprising less than 10 wt% silicon material, electrochemical energy-storage cells according to aspects of the present disclosure are able to comprise anodes having anode-active material comprising about 10 wt% to about 100 wt% silicon material. This increase in silicon material is enabled by including an electrolyte comprising a solvent having a sulfonamide functional group, and ultimately enhances electrochemical energy-storage cells by bringing higher energy density (more than about 350 wh / kg energy density), longer cycling life (improvement by about 233%), and improved power capability (improvement by about 25%).

[0026] In addition to being used in lithium-ion batteries, electrolytes disclosed herein may also be used in other alkali-metal-ion batteries (such as sodium-ion batteries, magnesium-ion batteries, and potassium-ion batteries) and lithium-sulfur batteries. The above benefits also apply in the context of other alkali-metal-ion batteries and lithium-sulfur batteries. This versatility enhances the utility of the electrolytes according to the present disclosure across various battery technologies.

[0027] FIG. 1 is a graph 100 showing discharge capacity over 300 cycles for a first new electrolyte 104 comprising a solvent having a sulfonamide functional group, and a first control carbonate electrolyte 108. The Y-axis of the graph 100 represents the discharge capacity measured 6 Attorney Docket No. 17468-184WOU1in milliampere-hours (mAh), while the X-axis denotes the cycle ID, indicating the number of cycles the battery has undergone. The new electrolyte 104 in FIG. 1 is composed of LiFSI salt dissolved in a sulfamoyl fluoride solvent comprising N,N-dimethyl sulfamoyl fluoride (DMSF), wherein the LiFSI salt had a concentration of about 2.3M. The control carbonate electrolyte 108 in FIG. 1 is composed of LiPFe / LiFSI salt dissolved in EC, EMC, and DEC solvents with VC and FEC additives, wherein LiPFe and LiFSI each had a concentration of about 0.6M. The first new electrolyte 104 and the first control carbonate electrolyte 108 were both used in a pure silicon-anode-based battery (meaning that the anode-active material comprised about 100 wt% silicon material) under a condition of 1C charge- 1C discharge cycles. The pure-silicon-anode-based batteries were each a 3-layer pouch cell having two anode layers each comprising about 100 wt% silicon material and one cathode layer comprising nickel, manganese, and cobalt. The new electrolyte 104 maintained a higher capacity consistently throughout the 300 cycles than the control carbonate electrolyte 108. The graph 100 provides support for the new electrolyte 104 improving cycling stability and discharge capacity. This performance enhancement is attributed to the sulfonamide functional group in the solvent, here the sulfamoyl fluoride. The sulfonamide functional group efficiently passivates the silicon anode, promoting the formation of a low-resistance passivation layer. This low-resistance passivation layer not only extends the cycling life of the anode material but also increases the discharge capacity and middle discharge voltage, leading to an overall rise in battery energy density. This improvement is beneficial for enhancing the performance and longevity of batteries, particularly those utilizing anode-active material comprising at least about 70 wt% silicon material.

[0028] FIGS. 2 through 4C show additional examples of new electrolytes comprising a solvent comprising a sulfonamide functional group providing increased cycle life, increased discharge capacity, increased capacity retention, increased remaining capacity after high-temperature storage, increased recovered capacity after high-temperature storage, and decreased direct current internal resistance (DCIR) after high-temperature storage. In these examples the solvent comprising the sulfonamide functional group comprises DMSF, and DMSF is used together with at least one carbonate solvent.

[0029] FIG. 2 is a graph 200 of cycle life versus cycle number for a second new electrolyte 204 comprising a solvent having a sulfonamide functional group and for a second control carbonate electrolyte 208. The second new electrolyte 204 and the second control carbonate electrolyte 208 were each evaluated in respective 1 Ah, 4.4 V pouch cells comprising a silicon-carbon and graphite anode having 12% silicon material, an NCM613 cathode, and 2% lithium aluminum titanium7 Attorney Docket No. 17468-184WOU1phosphate (LATP), with the anode having a specific capacity of 500 mAh / g. The pouch cells were evaluated under 1C charge / lC discharge cycling at 45°C and 4.4 V. The second new electrolyte 204 comprises 11.2 wt% lithium hexafluorophosphate (LiPFe), 8.2 wt% ethylene carbonate (EC), 16.4 wt% propylene carbonate (PC), 16.4 wt% ethyl methyl carbonate (EMC), 12.3 wt% diethyl carbonate (DEC), 4.2 wt% fluoroethylene carbonate (FEC), 28.7 wt% DMSF, 0.3 wt% lithium difluorophosphate (LiDFP), 0.5 wt% lithium difluoro(oxalato)borate (LiDFOB), 1.0 wt% 1,3,2-di oxathiolane-2, 2-di oxide (DTD), 0.5 wt% 1,3 -propane sultone (PS), and 0.3 wt% tetravinylsilane (TVS). The second control carbonate electrolyte 208 comprises 15.0 wt% LiPFe, 7.8 wt% EC, 15.6 wt% PC, 31.3 wt% EMC, 23.5 wt% DEC, 4.0 wt% FEC, 0.5 wt% LiDFP, 0.5 wt% LiDFOB, 1.0 wt% DTD, 0.5 wt% PS, and 0.3 wt% TVS. As shown in FIG. 2, under 1C charge / lC discharge cycling at 45 °C and 4.4 V, the second new electrolyte 204 provides longer cycle life than the second control carbonate electrolyte 208. FIG. 2 therefore demonstrates that DMSF can be used together with carbonate solvents in a silicon-containing electrochemical energy-storage cell and can improve cycle life under elevated-voltage and elevated-temperature conditions.

[0030] FIG. 3A is a graph 300 showing discharge capacity at 25°C and at -20°C for the second control carbonate electrolyte 208, a third new electrolyte 304, and a fourth new electrolyte 308. The second control carbonate electrolyte 208, the third new electrolyte 304, and the fourth new electrolyte 308 were each evaluated in respective 1 Ah, 4.4 V pouch cells comprising a siliconcarbon and graphite anode having 12% silicon material, an NCM613 cathode, and 2% lithium aluminum titanium phosphate (LATP), with the anode having a specific capacity of 500 mAh / g. For the testing associated with FIG. 3 A, the pouch cells were evaluated using a 1C discharge at 25°C and a 0.5C discharge at -20°C. The third new electrolyte 304 is composed of 15.0 wt% LiPFe, 7.8 wt% EC, 1.9 wt% PC, 31.3 wt% EMC, 23.5 wt% DEC, 4.0 wt% FEC, 13.7 wt% DMSF, 0.5 wt% LiDFP, 0.5 wt% LiDFOB, 1.0 wt% DTD, 0.5 wt% PS, and 0.3 wt% TVS. The fourth new electrolyte 308 is composed of 7.5 wt% LiPFe, 7.5 wt% lithium bis(fluorosulfonyl)imide (LiFSI), 7.8 wt% EC, 1.9 wt% PC, 31.3 wt% EMC, 23.5 wt% DEC, 4.0 wt% FEC, 13.7 wt% DMSF, 0.5 wt% LiDFP, 0.5 wt% LiDFOB, 1.0 wt% DTD, 0.5 wt% PS, and 0.3 wt% TVS. As shown in FIG. 3A, the third new electrolyte 304 and the fourth new electrolyte 308 provide higher low-temperature discharge capacity than the second control carbonate electrolyte 208.

[0031] FIG. 3B is a graph 312 showing capacity retention at -20°C for the second control carbonate electrolyte 208, the third new electrolyte 304, and the fourth new electrolyte 308. The second control carbonate electrolyte 208, the third new electrolyte 304, and the fourth new8 Attorney Docket No. 17468-184WOU1electrolyte 308 were each evaluated in respective 1 Ah, 4.4 V pouch cells comprising a siliconcarbon and graphite anode having 12% silicon material, an NCM613 cathode, and 2% LATP, with the anode having a specific capacity of 500 mAh / g. As shown in FIG. 3B, the third new electrolyte 304 and the fourth new electrolyte 308 provide higher capacity retention at -20°C than the second control carbonate electrolyte 208.

[0032] FIG. 3C is a graph 316 showing cycle life versus cycle number for the second control carbonate electrolyte 208, the third new electrolyte 304, and the fourth new electrolyte 308. The second control carbonate electrolyte 208, the third new electrolyte 304, and the fourth new electrolyte 308 were each evaluated in respective 1 Ah, 4.4 V pouch cells comprising a siliconcarbon and graphite anode having 12% silicon material, an NCM613 cathode, and 2% LATP, with the anode having a specific capacity of 500 mAh / g. For the testing associated with FIG. 3C, the pouch cells were evaluated under 1C charge / lC discharge cycling at 45°C and 4.4 V. As shown in FIG. 3C, the third new electrolyte 304 and the fourth new electrolyte 308 provide longer cycle life than the second control carbonate electrolyte 208.

[0033] FIG. 4A is a graph 400 showing average remaining capacity at 2 weeks and at 4 weeks of storage at 60°C for a third control carbonate electrolyte 404, a fifth new electrolyte 408, and a sixth new electrolyte 412. The third control carbonate electrolyte 404, the fifth new electrolyte 408, and the sixth new electrolyte 412 were each evaluated in respective 0.4 Ah, 4.2 V pouch cells comprising a silicon-carbon anode made of only silicon and carbon, here about 45 wt% to about 48 wt% silicon and about 55 wt% to about 52 wt% carbon, and an NCM cathode having a nickel content greater than 80%. The pouch cells were subjected to a 100% state-of-charge (SOC), 60°C storage test. The third control carbonate electrolyte 404 is composed of 15.12 wt% LiPFe, 2.74 wt% LiFSI, 21.0 wt% EC, 26.75 wt% DEC, 8.84 wt% FEC, and 25.55 wt% ethyl propionate (EP). The fifth new electrolyte 408 is composed of 15.04 wt% LiPFe, 2.73 wt% LiFSI, 20.9 wt% EC, 26.62 wt% DEC, 8.8 wt% FEC, 25.42 wt% EP, and 0.5 wt% DMSF. The sixth new electrolyte 412 is composed of 14.97 wt% LIPF6, 2.71 wt% LiFSI, 20.79 wt% EC, 26.49 wt% DEC, 8.75 wt% FEC, 25.3 wt% EP, and 1.0 wt% DMSF. As shown in FIG. 4A, the fifth new electrolyte 408 and the sixth new electrolyte 412 provide higher remaining capacity after high-temperature storage than the third control carbonate electrolyte 404.

[0034] FIG. 4B is a graph 416 showing average recovered capacity at 2 weeks and at 4 weeks of storage at 60°C for the third control carbonate electrolyte 404, the fifth new electrolyte 408, and the9 Atorney Docket No. 17468-184WOU1sixth new electrolyte 412. The third control carbonate electrolyte 404, the fifth new electrolyte 408, and the sixth new electrolyte 412 were each evaluated in respective 0.4 Ah, 4.2 V pouch cells comprising a silicon-carbon anode made of only silicon and carbon, here about 45 wt% to about 48 wt% silicon and about 55 wt% to about 52 wt% carbon, and an NCM cathode having a nickel content greater than 80%, under a 100% SOC, 60°C storage test. As shown in FIG. 4B, the fifth new electrolyte 408 and the sixth new electrolyte 412 provide higher recovered capacity after high-temperature storage than the third control carbonate electrolyte 404.

[0035] FIG. 4C is a graph 420 showing DCIR at 2 weeks and at 4 weeks of storage at 60°C for the third control carbonate electrolyte 404, the fifth new electrolyte 408, and the sixth new electrolyte 412. The third control carbonate electrolyte 404, the fifth new electrolyte 408, and the sixth new electrolyte 412 were each evaluated in respective 0.4 Ah, 4.2 V pouch cells comprising a silicon-carbon anode made of only silicon and carbon, here about 45 wt% to about 48 wt% silicon and about 55 wt% to about 52 wt% carbon, and an NCM cathode having a nickel content greater than 80%, under a 100% SOC, 60°C storage test. As shown in FIG. 4C, the fifth new electrolyte 408 and the sixth new electrolyte 412 exhibit lower DCIR growth after high-temperature storage than the third control carbonate electrolyte 404.

[0036] FIG. 5 illustrates a simplified electrochemical energy-storage cell 500 made in accordance with aspects of the present disclosure. Those skilled in the art will readily appreciate that the electrochemical energy-storage cell 500 can be, for example, a battery or a supercapacitor. In addition, those skilled in the art will readily understand that FIG. 5 illustrates only some basic functional components of the electrochemical energy-storage cell 500 and that a real-world instantiation of the electrochemical energy-storage cell, such as a secondary battery or a supercapacitor, will typically be embodied using either a wound construction or a stacked construction. Further, those skilled in the art will understand that the electrochemical energy-storage cell 500 will include other components, such as electrical terminals, seal(s), thermal shut-down layer(s), and / or vent(s), among other things, that, for ease of illustration, are not shown in FIG. 5.

[0037] In this example, the electrochemical energy-storage cell 500 includes a spaced-apart cathode 504 and anode 508, and a pair of corresponding respective current collectors 504A, 508A. A porous separator 512 is located between the cathode 504 and the anode 508 to electrically separate the cathode and the anode but to allow ions of an electrolyte 516 to flow therethrough. The porous separator 512 and / or one, the other, or both of the cathode 504 and the anode 508, depending on10 Atorney Docket No. 17468-184WOU1whether porous or not, is / are impregnated with the electrolyte 516. In FIG. 5, both the cathode 504 and the anode 508 are illustrated as being porous by way of the electrolyte 516 being illustrated as extending into them. The electrochemical energy-storage cell 500 includes a container 520 that contains the current collectors 504A, 508A, the cathode 504 and the anode 508, the porous separator 512, and the electrolyte 516. In some embodiments, the electrochemical energy-storage cell 500 is part of a greater battery system.

[0038] In some embodiments, the electrolyte 516 comprises an alkali-metal salt, such as a lithium salt, and a solvent system, wherein the solvent system comprises one or more solvents, and at least one of the one or more solvents has a sulfonamide functional group. As those skilled in the art will understand, depending upon the type and design of the electrochemical energy-storage cell 500, each of the cathode 504 and the anode 508 comprises a suitable material compatible with the alkali-metal ions and other constituents in the electrolyte 516. In some embodiments, the anode 508 comprises an anode-active material comprising silicon material. In some embodiments, the anodeactive material comprises at least about 5 wt% silicon material. In some other embodiments, the anode-active material comprises at least about 30 wt% silicon material, at least about 70 wt% silicon material, at least about 90 wt% silicon material, or about 100 wt% silicon material. In embodiments wherein the anode-active material comprises less than 100 wt% silicon material, the anode-active material may also comprise carbon, such as graphite. Each of the current collectors 504A, 508A may be made of any suitable electrically conducting material, such as copper or aluminum, or any combination thereof. The porous separator 512 may be made of any suitable porous dielectric material, such as a porous polymer, among others.

[0039] In some embodiments, the alkali-metal salt in the electrolyte 516 comprises lithium bis(fhiorosulfonyl)imide (LiFSI), lithium bis(trifhioromethane-sulfonyl)imide (LiTFSI), lithium (fluorosulfonyl)(trifluoromethanesulfonyl)imide (LiFTFSI), lithium (fluorosulfonyl)(trifluoromethylsulfonyl)amide (LiFTA), lithium bis(pentafluoroethanesulfonyl)imide (LiBETI), lithium-cyclo-difluoromethane- 1 , 1 -bi s -(sulfonyl)imide (LiDMSI), lithium 4,4,5,5-tetrafluoro-l,3,2-dithiazolidine-l,l,3,3-tetraoxide (LiCTFSI), lithium l,l,2,2,3,3-hexafluoropropane-l,3-disulfonimide (LiHFDF), lithium perchlorate (LiCIO-i), lithium tetrafluoroborate (LiBF4), lithium hexafluorophosphate (LiPFe), lithium hexafluoroantimonate (LiSbFe), lithium trifluoromethanesulfonate (LiTF), lithium 2-trifluoromethyl-4,5-dicyanoimidazolide (LiTDI), lithium tetracyanoborate (LiB(CN)4), lithium bis(oxalato)borate (LiBOB), lithium difluoro(oxalate)borate (LiDFOB), lithium difluoro(bisoxalato) phosphate11 Atorney Docket No. 17468-184WOU1(LiDFOP), lithium poly sulfide (LiPS), lithium difluorophosphate (LiDFP), a lithium-organic salt (i.e., organolithium lithium, alkoxide lithium, amide lithium, imide, thiolate lithium, phosphonate lithium, etc.), and / or a lithium-polymer salt (i.e., LiFSI-polymer, LiTFSI-polymer, etc.), among others. In some embodiments, the electrolyte 516 comprises both LiFSI and LiPFe. In addition, in alternative embodiments, any of the above-mentioned salts may have their lithium cation replaced with a different metal cation, such as sodium, potassium, rubidium, cesium, magnesium, zinc, aluminum, silver, or indium.

[0040] In some embodiments, the sulfonamide functional group in the solvent system comprises a sulfamoyl fluoride, such as N,N-dimethyl sulfamoyl fluoride (DMSF). In other embodiments, the functional group in the solvent system comprises N-ethyl-N-methyl sulfamoyl fluoride, N,N-dimethyl trifluoromethane-sulfonamide, l,l-difhioro-N,N-dimethyl methane sulfonamide, N,N-diethyl sulfamoyl fluoride, N-methyl-bis(fhiorosulfonyl)imide, morpholine-4-sulfamoyl fluoride, pyrrolidine sulfamoyl fluoride, bis(2-methoxy ethyl) sulfamoyl fluoride, N,N-dimethylmethanesulfonamide, N-(2,2,2-trifluoroethyl)imidodisulfuryl fluoride, N-(2-methoxyethyl)-N-methylsulfamoyl fluoride, 3 -fluoro- 1 -azetidinesulfonyl fluoride, 1 -pyrrolidinesulfonyl fluoride, (3 S)-3 -fluoro- 1-pyrrolidinesulfonyl fluoride, 2-oxo-3-oxazolidinesulfonyl fluoride, 2-ethy 1-1,1 -dioxo-isothiazolidine, 2-methyl-l,l-dioxo-isothiazolidine, N-methyl-N-(trimethylsilyl)sulfamoyl fluoride, and / or any other SO2-N group containing a sulfonamide. In some embodiments, the solvent system in the electrolyte 516 defines a solvent system weight, and the solvent comprising the sulfonamide functional group has a weight percentage in a range of about 0.1% to about 100%, or about 20% to about 100% of the solvent system weight. In some embodiments, the solvent comprising the sulfonamide functional group comprises DMSF, and the DMSF is present in an amount of about 0.5 wt% to about 50 wt% of a total weight of the solvent system. In some embodiments, the DMSF is present in an amount of at least about 10 wt% of the total weight of the solvent system. In some embodiments, the DMSF is present in an amount of about 10 wt% to about 20 wt% of the total weight of the solvent system. Similarly, the solvent system in the electrolyte 516 may define a solvent system volume or number of moles, and the solvent comprising the sulfonamide functional group has a volume or mole percentage in a range of about 0.1% to about 100%, or about 20% to about 100% of the solvent system volume or number of moles. In some embodiments, the solvent system in the electrolyte 516 comprises more than one solvent.

[0041] If one or more sulfonamide solvents are not the sole solvent(s) of the solvent system, a hybrid sulfonyl-containing electrolyte contains one or more non-sulfonyl-based cosolvents mixed 12 Attorney Docket No. 17468-184WOU1with the one or more sulfonyl-based solvent(s). Examples of non-sulfonyl-based cosolvents, additives (a cosolvent can be called an “additive” if the amount of the cosolvent is less than about 5 wt% of the total amount of the solvents in the hybrid solvent system), or diluents that can be used in a hybrid sulfonyl-containing cosolvent system and hybrid sulfonyl-containing cosolvent-based electrolyte of the present disclosure include, but are not limited to, boron-containing compounds and derivatives, ionic liquids, phosphonates, phosphonate derivatives, phosphites, phosphite derivatives, silyl ethers, silyl ether derivatives, isocyanates, isocyanate derivatives, carbonates, ethers, nitriles, phosphates, sulfonates, sulfones, sultones, and sulfates, either cyclic or linear, non-fluorinated, or fluorinated. In some embodiments, the one or more non-sulfonyl-based cosolvents comprise at least one carbonate solvent comprising one or more of ethylene carbonate (EC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), dimethyl carbonate (DMC), or propylene carbonate (PC). In some embodiments, the solvent system comprises at least one carbonate solvent and DMSF. In some embodiments, the one or more carbonate solvents are preferred cosolvents with DMSF because the one or more carbonate solvents provide good salt solubility and bulk ionic conductivity, while the DMSF contributes to formation of an inorganic-rich SEI that passivates a silicon-containing anode.

[0042] In some embodiments, the electrochemical energy-storage cell 500 is configured to operate at a voltage of at least about 4.2 V or at least about 4.3 V. In some embodiments, the electrochemical energy-storage cell 500 is configured to operate at a temperature of at least 40°C. In some embodiments, the electrochemical energy-storage cell 500 operates at a temperature below 0°C. In some embodiments, the electrochemical energy-storage cell 500 is stored at a temperature of at least 50°C. In some embodiments, the electrolyte 516 comprises DMSF and at least one carbonate solvent, and is configured to improve interfacial stability of a silicon-containing anode by forming a stabilized interphase on the silicon-containing anode, wherein the stabilized interphase comprises inorganic species, and wherein the inorganic species comprise LiF. In some embodiments, the at least one carbonate solvent provides ionic conductivity to the electrolyte 516, and the DMSF improves passivation of the silicon-containing anode.

[0043] Various batery and supercapacitor constructions that can be used for constructing the sulfonamide electrochemical energy-storage cell 500 of FIG. 5, are known in the art. If any of such known constructions is used, a novelty of the electrochemical energy-storage cell 500 lies in the electrolyte 516. Those skilled in the art will readily appreciate that in stacked constructions made of a plurality of anodes stacked with a plurality of cathodes and a plurality of separators, each anode may have anode-active material on both sides of the corresponding current collector 508A.13 Atorney Docket No. 17468-184WOU1

[0044] In some aspects, the present disclosure is directed to methods of manufacturing an electrochemical energy-storage cell comprising a high-capacity anode (such as an anode having an anode-active material that is at least about 70 wt% silicon material) and an electrolyte having a sulfonamide functional group. The electrochemical energy-storage cell and electrolyte may have any one or more of the properties of electrochemical energy-storage cells and electrolytes described above. For example, in some embodiments, methods of manufacturing the electrochemical energy -storage cell 500 of FIG. 5 comprise placing the anode 508 in the container 520, placing the porous separator 512 in the container on top of the anode, placing the cathode 504 in the container on top of the porous separator, adding the electrolyte 516 to the container, and sealing the container. Placing various of these elements “on top” of each other is not meant to be limited to a particular direction in space — the electrochemical energy-storage cell may be assembled in any direction.

[0045] FIG. 6 illustrates, in a flowchart, a method 600 of enhancing battery performance using an electrolyte according to aspects of the present disclosure. At step 604, an anode is placed in a container. In some embodiments, the anode includes a current collector and an anode-active material in electrical communication with the current collector, and the anode-active material comprises at least about 5 wt% silicon material. At step 608, a porous separator is placed in the container on top of the anode. At step 612, a cathode is placed in the container on top of the porous separator. At step 616, an electrolyte comprising an alkali-metal salt and a solvent having a sulfonamide functional group is added to the container such that the electrolyte is in contact with the anode-active material and the cathode and permeates the porous separator. At step 620, the container is sealed.

[0046] Methods of manufacturing an electrochemical energy-storage cell described herein improve battery performance by incorporating an electrolyte having a sulfonamide functional group into a battery and passivating the high-capacity anode with the sulfonamide functional group. These methods result in a battery that maintains a higher discharge capacity over numerous cycles and exhibits improved stability and reduced gassing at elevated temperatures compared to traditional batteries.

[0047] Various modifications and additions can be made without departing from the spirit and scope of this disclosure. Features of each of the various embodiments described above may be combined with features of other described embodiments as appropriate in order to provide a multiplicity of feature combinations in associated new embodiments. Furthermore, while the14 Attorney Docket No. 17468-184WOU1foregoing describes a number of separate embodiments, what has been described herein is merely illustrative of the application of the principles of the present invention. Additionally, although particular methods herein may be illustrated and / or described as being performed in a specific order, the ordering is highly variable within ordinary skill to achieve aspects of the present disclosure. Accordingly, this description is meant to be taken only by way of example, and not to otherwise limit the scope of this invention.

[0048] Exemplary embodiments have been disclosed above and illustrated in the accompanying drawings. It will be understood by those skilled in the art that various changes, omissions and additions may be made to that which is specifically disclosed herein without departing from the spirit and scope of the present invention.15 Atorney Docket No. 17468-184WOU1

Claims

What is claimed is:

1. An electrochemical energy-storage cell, comprising:an anode that includes a current collector and an anode-active material in electrical communication with the current collector, wherein the anode-active material comprises silicon material;a cathode;a porous separator disposed between the anode and the cathode, the porous separator electrically insulating the anode and the cathode relative to one another;a container that contains the anode, the cathode, and the porous separator; andan electrolyte in contact with the anode-active material and the cathode and permeating the porous separator, the electrolyte comprising:an alkali-metal salt; anda solvent system comprising at least one solvent, wherein at least one solvent comprises a sulfonamide functional group.

2. The electrochemical energy-storage cell of claim 1, wherein the anode-active material comprises at least about 0.5 wt% silicon material.

3. The electrochemical energy-storage cell of either of claims 1 and 2, wherein the anode-active material further comprises carbon.

4. The electrochemical energy-storage cell of claim 3, wherein the carbon comprises graphite.

5. The electrochemical energy-storage cell of claim 1, wherein the anode-active material consists of silicon and carbon.

6. The electrochemical energy-storage cell of any preceding claim, wherein the alkali-metal salt comprises at least one of LiFSI, LiPFe, LiTFSI, and LiBF4.

7. The electrochemical energy-storage cell of any preceding claim, wherein the sulfonamide functional group comprises a sulfamoyl fluoride group.

8. The electrochemical energy-storage cell of claim 1, wherein the sulfonamide functional group comprises at least one of N,N-dimethyl sulfamoyl fluoride, N-ethyl-N-methyl sulfamoyl fluoride, N,N-dimethyl trifhioromethane-sulfonamide, l,l-difluoro-N,N-dimethyl methane16 Attorney Docket No. 17468-184WOU1sulfonamide, N,N-diethyl sulfamoyl fluoride, N-methyl-bis(fluorosulfonyl)imide, morpholine-4- sulfamoyl fluoride, pyrrolidine sulfamoyl fluoride, bis(2-methoxyethyl) sulfamoyl fluoride, N,N- dimethylmethanesulfonamide, N-(2,2,2-trifluoroethyl)imidodisulfuryl fluoride, N-(2- methoxyethyl)-N-methylsulfamoyl fluoride, 3 -fluoro- 1 -azetidinesulfonyl fluoride, 1- pyrrolidinesulfonyl fluoride, (3S)-3-fluoro-l-pyrrolidinesulfonyl fluoride, 2-oxo-3- oxazolidinesulfonyl fluoride, 2-ethyl-l,l-dioxo-isothiazolidine, 2-methy 1-1,1 -di oxo- isothiazolidine, and N-methyl-N-(trimethylsilyl)sulfamoyl fluoride.

9. The electrochemical energy-storage cell of either of claims 7 and 8, wherein the solvent system has a solvent weight, and the solvent comprising the sulfamoyl fluoride functional group has a weight percentage in a range of 0.1% to 100% of the solvent weight.

10. The electrochemical energy-storage cell of claim 9, wherein the solvent comprising the sulfamoyl fluoride functional group has a weight percentage in a range of 20% to 100% of the solvent weight.

11. The electrochemical energy-storage cell of any preceding claim, wherein the solvent system comprises at least one solvent that does not comprise a sulfonamide functional group.

12. The electrochemical energy-storage cell of any preceding claim, wherein the solvent system further comprises at least one of an additive and a diluent.

13. The electrochemical energy-storage cell of claim 1, wherein the alkali-metal salt comprises a lithium salt, and the solvent system comprises at least one carbonate solvent and N,N-dimethyl sulfamoyl fluoride (DMSF), wherein the DMSF is present in an amount of about 0.5 wt% to about 50 wt% of the solvent system.

14. The electrochemical energy-storage cell of claim 13, wherein the DMSF is present in an amount of about 10 wt% to about 20 wt% of the solvent system.

15. The electrochemical energy-storage cell of claim 13, wherein the at least one carbonate solvent comprises one or more of ethylene carbonate (EC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), propylene carbonate (PC), or dimethyl carbonate (DMC).

16. The electrochemical energy-storage cell of claim 13, wherein the lithium salt comprises at least one of LiFSI and LiPFe.17 Atorney Docket No. 17468-184WOU117. The electrochemical energy-storage cell of claim 16, wherein the electrolyte comprises both LiFSI and LIPF6.

18. The electrochemical energy-storage cell of claim 1, wherein the anode-active material comprises at least about 5 wt% silicon material.

19. The electrochemical energy-storage cell of claim 18, wherein the anode-active material comprises at least about 30 wt% silicon material.

20. The electrochemical energy-storage cell of claim 1 , wherein the alkali-metal salt comprises a lithium salt, wherein the solvent system comprises at least one carbonate solvent and N,N- dimethyl sulfamoyl fluoride (DMSF), wherein the DMSF is present in an amount of at least about 10 wt% of the solvent system, wherein the cell is configured to operate at a voltage of at least about 4.2 V, and wherein the electrolyte is configured to improve interfacial stability of the anode.

21. The electrochemical energy-storage cell of claim 20, wherein the cell is configured to operate at a temperature of at least 40°C.

22. The electrochemical energy-storage cell of claim 20, wherein the electrolyte is configured to form a stabilized interphase on the anode.

23. The electrochemical energy-storage cell of claim 22, wherein the stabilized interphase comprises inorganic species.

24. The electrochemical energy-storage cell of claim 23, wherein the inorganic species comprise LiF.

25. The electrochemical energy-storage cell of claim 13, wherein the cell operates at a temperature below 0°C.

26. The electrochemical energy-storage cell of claim 20, wherein the cell operates at a temperature below 0°C.

27. The electrochemical energy-storage cell of claim 13, wherein the cell is stored at a temperature of at least 50°C.18 Atorney Docket No. 17468-184WOU128. The electrochemical energy-storage cell of claim 20, wherein the cell is stored at a temperature of at least 50°C.

29. A method of making an electrochemical energy-storage cell, comprising:placing an anode in a container, wherein the anode includes a current collector and an anodeactive material in electrical communication with the current collector, and the anode-active material comprises silicon material;placing a porous separator in the container on top of the anode;placing a cathode in the container on top of the porous separator, wherein the porous separator electrically insulates the anode and the cathode;adding an electrolyte to the container, wherein the electrolyte is in contact with the anodeactive material and the cathode and permeates the porous separator, the electrolyte comprising:an alkali-metal salt; anda solvent system comprising at least one solvent having a sulfonamide functional group;andsealing the container.

30. The method of making an electrochemical energy-storage cell of claim 29, wherein the anodeactive material comprises at least about 0.5 wt% silicon material.

31. The method of making an electrochemical energy-storage cell of either of claims 29 and 30, wherein the anode-active material further comprises carbon.

32. The method of making an electrochemical energy-storage cell of claim 31, wherein the carbon comprises graphite.

33. The method of making an electrochemical energy-storage cell of claim 29, wherein the anodeactive material consists of silicon and carbon.

34. The method of making an electrochemical energy-storage cell of any of claims 29-33, wherein the alkali-metal salt comprises at least one of LiFSI, LiPFe, LiTFSI, and LiBF4.

35. The method of making an electrochemical energy-storage cell of any of claims 29-34, wherein the solvent having a sulfonamide functional group comprises a sulfamoyl fluoride group.19 Atorney Docket No. 17468-184WOU136. The method of making an electrochemical energy-storage cell of claim 29, wherein the sulfonamide functional group containing solvent comprises at least one of N,N-dimethyl sulfamoyl fluoride, N-ethyl-N-methyl sulfamoyl fluoride, N,N-dimethyl trifluoromethanesulfonamide, l,l-difhioro-N,N-dimethyl methane sulfonamide, N,N-di ethyl sulfamoyl fluoride, N-methyl-bis(fluorosulfonyl)imide, morpholine-4-sulfamoyl fluoride, pyrrolidine sulfamoyl fluoride, bis(2-methoxyethyl) sulfamoyl fluoride, N,N-dimethylmethanesulfonamide, N-(2,2,2- trifluoroethyl)imidodisulfuryl fluoride, N-(2-methoxyethyl)-N-methylsulfamoyl fluoride, 3- fluoro-l-azetidinesulfonyl fluoride, 1 -pyrrolidines ulfonyl fluoride, (3 S)-3 -fluoro- 1- pyrrolidinesulfonyl fluoride, 2-oxo-3-oxazolidinesulfonyl fluoride, 2-ethyl- 1 , 1 -dioxo- isothiazolidine, 2-methyl-l,l-dioxo-isothiazolidine, and N-methyl-N-(trimethylsilyl)sulfamoyl fluoride.

37. The method of making an electrochemical energy-storage cell of either of claims 35 and 36, wherein the solvent system has a solvent weight, and the solvent comprising the sulfonamide functional group has a weight percentage in a range of 0.1% to 100% of the solvent weight.

38. The method of making an electrochemical energy-storage cell of claim 37, wherein the solvent comprising the sulfamoyl fluoride functional group has a weight percentage in a range of 20% to 100% of the solvent weight.

39. The method of making an electrochemical energy-storage cell of any of claims 29-38, wherein the solvent system comprises at least one solvent that does not comprise a sulfonamide functional group.

40. The method of making an electrochemical energy-storage cell of any of claims 29-39, wherein the solvent system further comprises at least one of an additive and a diluent.20 Atorney Docket No. 17468-184WOU1

Images