Methods and compositions for fast-charging anodes for lithium ion batteries

Abstract

Described herein is a solid electric conductor and methods of making and using the solid electric conductor. The solid electric conductor can include two discrete populations of particles intermixed. A first population of particles can include an ionically conducting solid-electrolyte, and a second population of particles can include an electrode active material. The compositions and methods described allow to achieve high specific energy, good cycle / calendar life, and low cobalt (Co) loading to reduce the cost of battery cells.

Description

[0001] METHODS AND COMPOSITIONS FOR FAST-CHARGING ANODES FOR

[0002] LITHIUM ION BATTERIES

[0003] CROSS-REFERENCE TO RELATED APPLICATIONS

[0004] This application claims benefit of priority of U.S. Provisional Application No. 63 / 635,829, filed April 18, 2024, which is incorporated herein by reference in its entirety.

[0005] BACKGROUND

[0006] Rechargeable lithium-ion batteries (LiBs) are major power sources for vehicle electrification because of high specific energy, low self-discharge, and being environmentally friendly. Significantly, the past decade has seen a trend toward nextgeneration lithium-ion batteries with high charge capacities / power densities developed for electric vehicles (EVs). In conventional LiBs, graphite has been adopted as anodes due to its low raw material cost, high reversible specific capacity, and decent ionic / electronic conductivity. However, graphite anodes in LiBs consistently exhibits severe capacity fading and poor safety while fast-charging battery cells or operating at high voltages (e.g., > 4.3 V vs. Li). One of the main obstacles restraining the performance of graphite anodes is instability and poor transport properties of solid-electrolyte interface (SEI) layer forming on the graphite surfaces. Although significant R&D efforts have been devoted to producing a robust SEI layer on graphite to increase lifespan of LiBs, the current LiBs still cannot accommodate extreme fast charging (e.g., 15 minute charging LiBs) due to poor Li-ion transport kinetics across the SEI layer, particularly at low temperatures (e.g., < 10°C).

[0007] To provide improved batteries for EV applications, there is a need to improve anode chemistry, in particular Li-ion transport kinetics across the SEI layer at the anode..

[0008] The compositions and methods disclosed herein address these and other needs.

[0009] SUMMARY

[0010] The SEI layer is carefully designed and produced during the formation cycles of newly fabricated LiB cells in a factory. During repeated battery cycles, however, graphite anodes experience volumetric changes (~ 13% per cycle) and its consequent mechanical stress damages the SEI layers. In addition, side-reaction products migrating from cathodes such as transition metal ions (e.g., Mn, Ni, Co ions) and HF can damage the pre-formed SEI. As a result, SEI continuously grows as a loosely aggregated, sparse form on the anode surface by consuming active lithium ions and electrolyte materials.

[0011] Establishing a stable artificial surface coating layer on the anode materials can improve the mechanical and thermal stability of the SEI by preventing direct contact between the electrolyte and electrode and reducing the irreversible capacity loss. Examples of coating materials include single-component inorganic oxide or polymers such as AI2O3, Li4TisOi2, TiCh, polyelectrolytes, and conducting polymers. However, most of these coating materials (e.g., AI2O3 and TiCh) have low Li-ion conductivity, which undermines the Li-ion transport across graphite - electrolyte interphase, further deteriorating the already subpar rate capability of graphite anode. Further, the extra coating process also increase the materials costs of the battery.

[0012] Herein, a strategy for improving the stability and Li-ion conductivity of the SEI layer at the anode is described. This strategy can be used to provide fast-charging and high- voltage operating LiBs.

[0013] The approach can involve blending a Li-conducting solid electrolyte (SE) powder with an anode material (e.g., graphite) in a powder or electrode manufacturing processes. This blending process can be customized for various materials combinations (e.g., types of SEs or particle sizes) or electrode designs (e.g., homogeneity of blending or microstructures) for practical applications. The versatile blending scheme offers a variety of advantages, including manufacturing friendliness and low processing cost. For example, the SE powders can be simply blended in anode slurry as a form of conductive additive, which is fully compatible with existing manufacturing processes and thus does not implement any extra cost. Alternatively, SE powders with nano-scale can be coated onto anode active materials, similar to the existing coating processes, by dry mixing or wet mixing.

[0014] The SE blended anodes can offer following advantages. First, the highly Li-ion conducting SEs (e.g., > 10'4S / cm) on the surfaces of anode active materials become the part of SEI ingredients during the formation cycle of battery cells and significantly improve Li- ion transport. Second, the SEs on the surface of anodes act as physical coating layers and protect the anode surfaces. Third, some of the SEs can scavenge moisture and / or protons and mitigate their parasitic reactions occurring at the SEI.

[0015] Due to the rapid Li-ion transport across the SEI, the SE blended anodes can support fast-charging LiB cells. At the same time, the improved stability of SEI from the SE blended anodes enables high-voltage operation of LiB cells (e.g., > 4.3 V vs. Li). The details of one or more embodiments of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims.

[0016] DESCRIPTION OF DRAWINGS

[0017] FIG. 1 schematically illustrates an example anode that includes a Li-conducting solid electrolyte (SE) powder.

[0018] FIG. 2 shows SEM and EDS micrographs of anodes that include 0 wt% LLTZ and 5 wt% LLZT. As shown in the micrographs, at a concentration of 5 wt% LLZT, the LLZT particles are evenly distributed across the surface of graphite, forming a dense protective layer on the anode surface.

[0019] FIG. 3 includes plots detailing the electrochemical performance of graphite anodes containing varying concentrations of LLZT blended into the graphite anode.

[0020] FIG. 4 compares X-ray photoelectron spectroscopy (XPS) performed on fresh graphite and anodes that include 0 wt% LLTZ and 5 wt% LLZT.

[0021] FIG. 5 compares the half-cell electrochemical performance of Si anode with varying amount of LLZT. Both tests were run within voltage ranges of 2.9 - 4.4 V vs. Li at 25 °C. The C-rates used are specified within the plots.

[0022] DETAILED DESCRIPTION

[0023] A number of embodiments of the disclosure have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention.

[0024] Definitions

[0025] To facilitate understanding of the disclosure set forth herein, a number of terms are defined below. Unless defined otherwise, all technical and scientific terms used herein generally have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0026] General Definitions

[0027] To facilitate understanding of the disclosure set forth herein, a number of terms are defined below. Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of skill in the art to which the disclosed invention belongs. Publications cited herein and the materials for which they are cited are specifically incorporated by reference.

[0028] As used in this specification and the following claims, the terms “comprise” (as well as forms, derivatives, or variations thereof, such as “comprising” and “comprises”) and “include” (as well as forms, derivatives, or variations thereof, such as “including” and “includes”) are inclusive (i.e., open-ended) and do not exclude additional elements or steps. For example, the terms "comprise" and / or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. Other than where noted, all numbers expressing quantities of ingredients, reaction conditions, geometries, dimensions, and so forth used in the specification and claims are to be understood at the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, to be construed in light of the number of significant digits and ordinary rounding approaches.

[0029] Accordingly, these terms are intended to not only cover the recited element(s) or step(s), but may also include other elements or steps not expressly recited. Furthermore, as used herein, the use of the terms “a”, “an”, and “the” when used in conjunction with an element may mean “one,” but it is also consistent with the meaning of “one or more,” “at least one,” and “one or more than one.” Therefore, an element preceded by “a” or “an” does not, without more constraints, preclude the existence of additional identical elements.

[0030] Ranges can be expressed herein as from “about” one particular value, and / or to “about” another particular value. By “about” is meant within 5% of the value, e.g., within 4, 3, 2, or 1% of the value. When such a range is expressed, another aspect includes from the one particular value and / or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. It is also understood that there are a number of values disclosed herein, and that each value is also herein disclosed as “about” that particular value in addition to the value itself. For example, if the value “10” is disclosed, then “about 10” is also disclosed. A range may be construed to include the start and the end of the range. For example, a range of 10% to 20% (i.e., range of 10%-20%) can includes 10% and also includes 20%, and includes percentages in between 10% and 20%, unless explicitly stated otherwise herein.

[0031] As used herein, the terms "may," "optionally," and "may optionally" are used interchangeably and are meant to include cases in which the condition occurs as well as cases in which the condition does not occur. Thus, for example, the statement that a formulation "may include an excipient" is meant to include cases in which the formulation includes an excipient as well as cases in which the formulation does not include an excipient.

[0032] It is understood that when combinations, subsets, groups, etc. of elements are disclosed (e.g., combinations of components in a composition, or combinations of steps in a method), that while specific reference of each of the various individual and collective combinations and permutations of these elements may not be explicitly disclosed, each is specifically contemplated and described herein.

[0033] A “control” is an alternative subject or sample used in an experiment for comparison purposes. A control can be "positive" or "negative."

[0034] Reference will now be made in detail to specific aspects of the disclosed materials, compounds, compositions, articles, and methods, examples of which are illustrated in the accompanying Examples and Figures.

[0035] Described herein are approaches to enhance stability and performance of anodes that is suitable for fast-charging LiBs and extending operating voltage of LiBs. The approach can involve blending a Li-conducting solid electrolyte (SE) powder with an anode material (e.g., graphite) in a powder or electrode manufacturing processes. This blending process can be customized for various materials combinations (e.g., types of SEs or particle sizes) or electrode designs (e.g., homogeneity of blending or microstructures) for practical applications. The versatile blending scheme offers a variety of advantages, including manufacturing friendliness and low processing cost. For example, the SE powders can be simply blended in anode slurry as a form of conductive additive, which is fully compatible with existing manufacturing processes and thus does not implement any extra cost. Alternatively, SE powders with nano-scale can be coated onto anode active materials, similar to the existing coating processes, by dry mixing or wet mixing.

[0036] The SE blended anodes can offer following advantages. First, the highly Li-ion conducting SEs (e.g., > 10'4S / cm) on the surfaces of anode active materials become the part of SEI ingredients during the formation cycle of battery cells and significantly improve Li- ion transport. Second, the SEs on the surface of anodes act as physical coating layers and protect the anode surfaces. Third, some of the SEs can scavenge moisture and / or protons and mitigate their parasitic reactions occurring at the SEI.

[0037] Due to the rapid Li-ion transport across the SEI, the SE blended anodes can support fast-charging LiB cells. At the same time, the improved stability of SEI from the SE blended anodes enables high-voltage operation of LiB cells (e.g., > 4.3 V vs. Li).

[0038] Anodes

[0039] Provided herein are anodes that comprise a population of particles comprising an ionically conducting solid-electrolyte disposed on an anode material, intermixed with an anode material, or a combination thereof.

[0040] In some embodiments, the population of particles comprising the ionically conducting solid-electrolyte can be disposed on a surface of the anode material.

[0041] In other embodiments, the population of particles comprising the ionically conducting solid-electrolyte can be intermixed with a second population of particles comprising the anode material.

[0042] The relative amount of the ionically conducting solid-electrolyte present in the anode can be varied. For example, in some embodiments, the population of particles comprising the ionically conducting solid-electrolyte is present in an amount of from 1 wt% to 10 wt%, based on the total weight of the anode.

[0043] In some embodiments, the population of particles comprising the ionically conducting solid-electrolyte can exhibit an average particle size of from 20 nm to 30 pm (e.g., from 20 nm to 50 nm, from 20 nm to 100 nm, from 20 nm to 250 nm, from 20 nm to 500 nm, from 20 nm to 750 nm, from 20 nm to 1 pm, from 20 nm to 5 pm, from 20 nm to 10 pm, from 20 nm to 15 pm, from 20 nm to 20 pm, from 20 nm to 25 pm, from 50 nm to 100 nm, from 50 nm to 250 nm, from 50 nm to 500 nm, from 50 nm to 750 nm, from 50 nm to 1 pm, from 50 nm to 5 pm, from 50 nm to 10 pm, from 50 nm to 15 pm, from 50 nm to 20 pm, from 50 nm to 25 pm, from 50 nm to 30 pm, from 100 nm to 250 nm, from 100 nm to 500 nm, from 100 nm to 750 nm, from 100 nm to 1 pm, from 100 nm to 5 pm, from 100 nm to 10 pm, from 100 nm to 15 pm, from 100 nm to 20 pm, from 100 nm to 25 pm, from 100 nm to 30 pm, from 250 nm to 500 nm, from 250 nm to 750 nm, from 250 nm to 1 pm, from 250 nm to 5 pm, from 250 nm to 10 pm, from 250 nm to 15 pm, from 250 nm to 20 pm, from 250 nm to 25 pm, from 250 nm to 30 pm, from 500 nm to 750 nm, from 500 nm to 1 pm, from 500 nm to 5 pm, from 500 nm to 10 pm, from 500 nm to 15 pm, from 500 nm to 20 pm, from 500 nm to 25 pm, from 500 nm to 30 pm, from 1 pm to 5 pm, from 1 pm to 10 pm, from 1 pm to 15 pm, from 1 pm to 20 pm, from 1 pm to 25 pm, from 1 pm to 30 pm, from 5 pm to 10 pm, from 5 pm to 15 pm, from 5 pm to 20 pm, from 5 pm to 25 pm, from 5 pm to 30 pm, from 10 pm to 15 pm, from 10 pm to 20 pm, from 10 pm to 25 pm, from 10 pm to 30 pm, from 15 pm to 20 pm, from 15 pm to 25 pm, from 15 pm to 30 pm, from 20 pm to 25 pm, from 20 pm to 30 pm, or from 25 pm to 30 pm).

[0044] In some embodiments, the population of particles comprising the ionically conducting solid-electrolyte can have a spherical shape.

[0045] In some embodiments, the ionically conducting solid-electrolyte can include at least one of the following compounds a) through g): a) LiPON (lithium phosphorus oxynitride or LisPCh (lithium phosphate); b) garnets of general formula LiyA3B20i2 in a predominantly cubic crystal structure, where A is selected from at least one element of the group La, K, Mg, Ca, Sr, and Ba, B is selected from at least one element of the group Zr, Hf, Nb, Ta, W, In, Sn, Sb, Bi, and Te, and 3 < y < 7. A predominantly cubic crystal structure is a crystal structure for which at least 80 vol % is made up of a cubic crystal structure. Particularly preferred are garnets of formula LiyA3B20i2, where A = La, and B is selected from Zr, Nb, Ta, and Te. One preferred specific embodiment is garnets of general formula Li7-xLa3Zr2-xMxOi2, where M stands for Nb, Ta, or a mixture of the two elements, and 2>x>0, in particular 1.5>x >0.5, or 1.5>x >0.2 (LLZT). Another preferred specific embodiment is garnets of general formula Li7-3zAlzLa3Zr2-xMxOi2, where M stands for Nb, Ta, or a mixture of the two elements, 2>x>0, in particular 1.5>x >0.5 and 0<z<0.3; c) perovskites of general formula Li3xLa2 / 3-xTiO3, where 2 / 3>x>0, in particular 0.5> x >0.2; d) compounds of the NASICON type, represented by general formula Lii+XRXM2- X(PO4)3, where M is selected from at least one element of the group Ti, Ge, and Hf, R is selected from at least one element of the group Al, B, Sn, and Ge, and 0<x<2. In one specific embodiment x = 0. In one preferred specific embodiment M = Ti. One preferred specific embodiment is a compound of general formula Lii+xAlxGeyTi2-x-y(PO4)3 (LAGP or LATP), where 0<x<2, 0<y<2, and 0<x+y<2; it is particularly preferred that 0<x<l, 0<y<l, and 0<x+y<2; e) Lithium-ion-conducting sulfide glasses of general formula x(Li2S)«y(P2S3)«z(MnSm), where MnSm has the meaning SnS2, GeS2, B2S3, or SiS2, and x, y, and z may each independently assume a value of 0 to 100, with the condition that x + y + z = 100. One preferred specific embodiment is sulfidic glasses where 60<x<90, 30<y<60 , and z = 0. It is particularly preferred that x = 70, y = 30, and z = 0. Further preferred specific embodiments are sulfidic glasses having the composition x (Li2S) • (P2Ss)’z(GeS2), where y = z = 14 and x = 72; f) argyrodites of formula LiePSsX, where X may be selected from Cl, Br, and I; preferred specific embodiments are LiePSsCl and LieGPSsBr; LiePSsCl is particularly preferred; and / or g) polymer electrolytes based on polyethylene oxide (PEO); for increasing the lithium ion conductivity, the polymer electrolytes preferably include lithium salts selected from lithium hexafluorophosphate (LiPFe), lithium tetrafluoroborate (LiBF4), LiSbFe, LiAsFe, Li(CF3)SO2NSO2(CF3) (LiTFSI) , LiCICh, lithium bis(oxalato)borate (Li[B(C2O4)2], LiBOB), and / or lithium difluoro(oxalato)borate (Li[BF2(C2O4)], LiDFOB).

[0046] In some embodiments, the ionically conducing solid-electrolyte can include Li?La3Zr20i2 (LLZO), Lii.4Alo.4Tii.6 P04)3 (LATP), Lio.sLao.sTiCh (LLTO), LisPCh, Li2HPO4, Li6.75La3Zn.75Tao.250i2 (LLZT), or any combination thereof.

[0047] In some embodiments, the ionically conducing solid-electrolyte can include Li?La3Zr20i2 (LLZO), Lii.4Alo.4Tii.6 P04)3 (LATP), Lio.sLao.sTiOs (LLTO), Li3PO4, Li2HPO4, or Li6.75La3Zn.75Tao.250i2 (LLZT).

[0048] In some embodiments, the anode material can comprise graphite.

[0049] In some embodiments, the anode further comprises a binder, a carbon conductive material, a passivation layer, or any combination thereof.

[0050] In some embodiments, the population of particles comprising the ionically conducting solid-electrolyte can be physically blended with a second population of particles comprising the anode material. In some embodiments, the population of particles comprising the ionically conducting solid-electrolyte can be wet-chemically coated on the anode material (e.g., on a second population of particles comprising the anode material). In some embodiments, the population of particles comprising the ionically conducting solid- electrolyte can be physically absorbed on the anode material (e.g., on a second population of particles comprising the anode material).

[0051] Method of Making

[0052] Also provided herein are methods of making anodes. In some embodiments, these methods can comprise contacting a first population of particles comprising an ionically conducting solid-electrolyte with a second population of particles comprising an anode material.

[0053] In some embodiments, the anode material and the ionically conducting solidelectrolyte can be in the form of a powder. In some embodiments, contacting the anode with the ionically conducting solid-electrolyte can include physically blending the ionically conducting solid-electrolyte and the anode material. In some embodiments, physical blending can be performed by mechanical mixing or dropcast mixing.

[0054] In some other embodiments, contacting the anode material with the ionically conducting solid-electrolyte can include wet chemical coating the ionically conducting solid-electrolyte on the anode material. In some other embodiments, wet chemical coating can be performed by a sol-gel, hydrothermal, or solvothermal synthesis process.

[0055] In some other embodiments, contacting the anode material with the ionically conducting solid-electrolyte can include physical absorption of the ionically conducting solid electrolyte on the anode material. In some embodiments, physical absorption can be performed by aerosol spray, a roll to roll deposition, casting, or a lamination process.

[0056] In some embodiments, the method can further include a physical characterization step that can be performed using microscopy, XRD, Raman spectroscopy, or any combination thereof.

[0057] In some embodiments, the ionically conducting solid-electrolyte can include at least one of the following compounds a) through g): a) LiPON (lithium phosphorus oxynitride or LisPCh (lithium phosphate); b) garnets of general formula LiyA3B20i2 in a predominantly cubic crystal structure, where A is selected from at least one element of the group La, K, Mg, Ca, Sr, and Ba, B is selected from at least one element of the group Zr, Hf, Nb, Ta, W, In, Sn, Sb, Bi, and Te, and 3 < y < 7. A predominantly cubic crystal structure is a crystal structure for which at least 80 vol % is made up of a cubic crystal structure. Particularly preferred are garnets of formula LiyA3B20i2, where A = La, and B is selected from Zr, Nb, Ta, and Te. One preferred specific embodiment is garnets of general formula Li7-xLa3Zr2-xMxOi2, where M stands for Nb, Ta, or a mixture of the two elements, and 2>x>0, in particular 1.5>x >0.5, or 1.5>x >0.2 (LLZT). Another preferred specific embodiment is garnets of general formula Li7-3zAlzLa3Zr2-xMxOi2, where M stands for Nb, Ta, or a mixture of the two elements, 2>x>0, in particular 1.5>x >0.5 and 0<z<0.3; c) perovskites of general formula Li3xLa2 / 3-xTiO3, where 2 / 3>x>0, in particular 0.5> x >0.2; d) compounds of the NASICON type, represented by general formula Lii+xRxNfc- X(PO4)3, where M is selected from at least one element of the group Ti, Ge, and Hf, R is selected from at least one element of the group Al, B, Sn, and Ge, and 0<x<2. In one specific embodiment x = 0. In one preferred specific embodiment M = Ti. One preferred specific embodiment is a compound of general formula Lii+xAlxGeyTi2-x-y(PO4)3 (LAGP or LATP), where 0<x<2, 0<y<2, and 0<x+y<2; it is particularly preferred that 0<x<l, 0<y<l, and 0<x+y<2; e) Lithium-ion-conducting sulfide glasses of general formula x(Li2S)«y(P2S3)«z(MnSm), where MnSm has the meaning SnS2, GeS2, B2S3, or SiS2, and x, y, and z may each independently assume a value of 0 to 100, with the condition that x + y + z = 100. One preferred specific embodiment is sulfidic glasses where 60<x<90, 30<y<60 , and z = 0. It is particularly preferred that x = 70, y = 30, and z = 0. Further preferred specific embodiments are sulfidic glasses having the composition x (Li2S) • (P2Ss)’z(GeS2), where y = z = 14 and x = 72; f) argyrodites of formula LiePSsX, where X may be selected from Cl, Br, and I; preferred specific embodiments are LiePSsCl and LieGPSsBr; LiePSsCl is particularly preferred; and / or g) polymer electrolytes based on polyethylene oxide (PEO); for increasing the lithium ion conductivity, the polymer electrolytes preferably include lithium salts selected from lithium hexafluorophosphate (LiPFe), lithium tetrafluoroborate (LiBF4), LiSbFe, LiAsFe, Li(CF3)SO2NSO2(CF3) (LiTFSI) , LiCICh, lithium bis(oxalato)borate (Li[B(C2O4)2], LiBOB), and / or lithium difluoro(oxalato)borate (Li[BF2(C2O4)], LiDFOB). In some embodiments, the ionically conducing solid-electrolyte can include Li?La3Zr20i2 (LLZO), Lii.4Alo.4Tii.6 P04)3 (LATP), Lio.sLao.sTiCh (LLTO), LisPCh, Li2HPO4, Li6.75La3Zn.75Tao.250i2 (LLZT), or any combination thereof.

[0058] In some embodiments, the ionically conducing solid-electrolyte can include Li?La3Zr20i2 (LLZO), Lii.4Alo.4Tii.6 P04)3 (LATP), Lio.sLao.sTiOs (LLTO), Li3PO4, Li2HPO4, or Li6.75La3Zn.75Tao.250i2 (LLZT).

[0059] In some embodiments, the anode material can comprise graphite.

[0060] In some embodiments, the anode material can further include a binder, a carbon conductive material, a passivation layer, or any combination thereof. In some embodiments, the anode material can further include a binder. In some embodiments, the anode material can further include a carbon conductive material. In some embodiments, the anode material can further include a passivation layer. In some embodiments, the anode material can further include a binder, a carbon conductive material, and a passivation layer. In some embodiments, the anode material can further include a binder and a carbon conductive material. In some embodiments, the anode material can further include a binder and a passivation layer. In some embodiments, the anode material can further include a carbon conductive material and a passivation layer.

[0061] In some embodiments, the first population of particles can exhibit an average particle size of from 20 nm to 30 pm (e.g., from 20 nm to 50 nm, from 20 nm to 100 nm, from 20 nm to 250 nm, from 20 nm to 500 nm, from 20 nm to 750 nm, from 20 nm to 1 pm, from 20 nm to 5 pm, from 20 nm to 10 pm, from 20 nm to 15 pm, from 20 nm to 20 pm, from 20 nm to 25 pm, from 50 nm to 100 nm, from 50 nm to 250 nm, from 50 nm to 500 nm, from 50 nm to 750 nm, from 50 nm to 1 pm, from 50 nm to 5 pm, from 50 nm to 10 pm, from 50 nm to 15 pm, from 50 nm to 20 pm, from 50 nm to 25 pm, from 50 nm to 30 pm, from 100 nm to 250 nm, from 100 nm to 500 nm, from 100 nm to 750 nm, from 100 nm to 1 pm, from 100 nm to 5 pm, from 100 nm to 10 pm, from 100 nm to 15 pm, from 100 nm to 20 pm, from 100 nm to 25 pm, from 100 nm to 30 pm, from 250 nm to 500 nm, from 250 nm to 750 nm, from 250 nm to 1 pm, from 250 nm to 5 pm, from 250 nm to 10 pm, from 250 nm to 15 pm, from 250 nm to 20 pm, from 250 nm to 25 pm, from 250 nm to 30 pm, from 500 nm to 750 nm, from 500 nm to 1 pm, from 500 nm to 5 pm, from 500 nm to 10 pm, from 500 nm to 15 pm, from 500 nm to 20 pm, from 500 nm to 25 pm, from 500 nm to 30 pm, from 1 pm to 5 pm, from 1 pm to 10 pm, from 1 pm to 15 pm, from 1 pm to 20 pm, from 1 pm to 25 pm, from 1 pm to 30 pm, from 5 pm to 10 pm, from 5 pm to 15 pm, from 5 pm to 20 pm, from 5 pm to 25 pm, from 5 pm to 30 pm, from 10 pm to 15 pm, from 10 pm to 20 pm, from 10 pm to 25 pm, from 10 pm to 30 pm, from 15 pm to 20 pm, from 15 pm to 25 pm, from 15 pm to 30 pm, from 20 pm to 25 pm, from 20 pm to 30 pm, or from 25 pm to 30 pm).

[0062] In some embodiments, the second population of particles can exhibit an average particle size of from 20 nm to 30 pm (e.g., from 20 nm to 50 nm, from 20 nm to 100 nm, from 20 nm to 250 nm, from 20 nm to 500 nm, from 20 nm to 750 nm, from 20 nm to 1 pm, from 20 nm to 5 pm, from 20 nm to 10 pm, from 20 nm to 15 pm, from 20 nm to 20 pm, from 20 nm to 25 pm, from 50 nm to 100 nm, from 50 nm to 250 nm, from 50 nm to 500 nm, from 50 nm to 750 nm, from 50 nm to 1 pm, from 50 nm to 5 pm, from 50 nm to 10 pm, from 50 nm to 15 pm, from 50 nm to 20 pm, from 50 nm to 25 pm, from 50 nm to 30 pm, from 100 nm to 250 nm, from 100 nm to 500 nm, from 100 nm to 750 nm, from 100 nm to 1 pm, from 100 nm to 5 pm, from 100 nm to 10 pm, from 100 nm to 15 pm, from 100 nm to 20 pm, from 100 nm to 25 pm, from 100 nm to 30 pm, from 250 nm to 500 nm, from 250 nm to 750 nm, from 250 nm to 1 pm, from 250 nm to 5 pm, from 250 nm to 10 pm, from 250 nm to 15 pm, from 250 nm to 20 pm, from 250 nm to 25 pm, from 250 nm to 30 pm, from 500 nm to 750 nm, from 500 nm to 1 pm, from 500 nm to 5 pm, from 500 nm to 10 pm, from 500 nm to 15 pm, from 500 nm to 20 pm, from 500 nm to 25 pm, from 500 nm to 30 pm, from 1 pm to 5 pm, from 1 pm to 10 pm, from 1 pm to 15 pm, from 1 pm to 20 pm, from 1 pm to 25 pm, from 1 pm to 30 pm, from 5 pm to 10 pm, from 5 pm to 15 pm, from 5 pm to 20 pm, from 5 pm to 25 pm, from 5 pm to 30 pm, from 10 pm to 15 pm, from 10 pm to 20 pm, from 10 pm to 25 pm, from 10 pm to 30 pm, from 15 pm to 20 pm, from 15 pm to 25 pm, from 15 pm to 30 pm, from 20 pm to 25 pm, from 20 pm to 30 pm, or from 25 pm to 30 pm).

[0063] In some embodiments, the first population of particles can exhibit an average particle size and the second population of particles exhibits an average particle size, and wherein the average particle size of the first population of particles is from 0.005 to 200 of the average particle size of the second population of parti cles(e.g., from 0.005 to 150, from 0.005 to 100, from 0.005 to 50, from 0.005 to 25, from 0.005 to 10, from 0.005 to 5, from 0.005 to 1, from 0.005 to 0.5, from 0.005 to 0.1, from 0.005 to 0.05, from 0.05 to 200, from 0.05 to 150, from 0.05 to 100, from 0.05 to 50, from 0.05 to 25, from 0.05 to 10, from 0.05 to 5, from 0.05 to 1, from 0.05 to 0.5, from 0.05 to 0.1, from 0.5 to 200, from 0.5 to 150, from 0.5 to 100, from 0.5 to 50, from 0.5 to 25, from 0.5 to 10, from 0.5 to 5, from 0.5 to 1, from 1 to 200, from 1 to 150, from 1 to 100, from 1 to 50, from 1 to 25, from 1 to 10, from 1 to 5, from 5 to 200, from 5 to 150, from 5 to 100, from 5 to 50, from 5 to 25, from 5 to 10, from 10 to 200, from 10 to 150, from 10 to 100, from 10 to 50, from 10 to 25, from 25 to 200, from 25 to 150, from 25 to 100, from 25 to 50, from 50 to 200, from 50 to 150, from 50 to 100, from 100 to 150, or from 100 to 200). In some embodiments, the first population of particles, the second population of particles, or any combination thereof can have a spherical shape.

[0064] In some embodiments, the first population of particles and the second population of particles can be present in a weight ratio of from 1 : 1000 to 1 :5 (e.g., 1 : 1000 to 1 :750, 1:1000 to 1:500, 1:1000 to 1:250, 1:1000 to 1:200, 1:1000 to 1:150, 1:1000 to 1:100, 1:1000 to 1:50, 1:1000 to 1:25, 1:1000 to 1:10, 1:500 to 1:250, 1:500 to 1:200, 1:500 to 1:150, 1:500 to 1:100, 1:500 to 1:50, 1:500 to 1:25, 1:500 to 1:10, 1:500 to 1:5, 1:250 to 1:200, 1:250 to 1:150, 1:250 to 1:100, 1:250 to 1:50, 1:250 to 1:25, 1:250 to 1:10, 1:250 to 1:5, 1:200 to 1:150, 1:200 to 1:100, 1:200 to 1:50, 1:200 to 1:25, 1:200 to 1:10, 1:200 to 1:5, 1:100 to 1:50, 1:100 to 1:25, 1:100 to 1:10, 1:100 to 1:5, 1:50 to 1:25, 1:50 to 1:10, 1:50 to 1:5, 1:25 to 1:10, 1:25 to 1:5, or l:10to 1:5).

[0065] In some embodiments, the first population of particles comprising the ionically conducting solid-electrolyte are present in an amount of from 1 wt% to 10 wt%, based on the total weight of the anode.

[0066] Batteries

[0067] Also disclosed herein are batteries that include an anode and a cathode disposed in a housing; and an electrolyte disposed between the cathode and the anode providing an ionically conductive pathway between the anode and the cathode. In some embodiments, the anode can include an anode material and an ionically conducting solid-electrolyte. In some embodiments, the cathode material can include a layered structured cathode material. In some embodiments, the ionically conducting solid-electrolyte can be present in an effective amount such that the battery can exhibit greater than 60% capacity retention during 1000 cycles above 4.3 V (e.g., greater than 65% capacity retention during 1000 cycles above 4.3 V, greater than 70% capacity retention during 1000 cycles above 4.3 V, or greater than 75% capacity retention during 1000 cycles above 4.3 V). In some embodiments, the ionically conducting solid-electrolyte can be present in an effective amount such that the battery can exhibit from greater than 60% to 98% capacity retention during 1000 cycles above 4.3V (e.g., from 65% to 98% capacity retention during 1000 cycles above 4.3V, from 70% to 98% capacity retention during 1000 cycles above 4.3V, from 75% to 98% capacity retention during 1000 cycles above 4.3 V, from 60% to 90% capacity retention during 1000 cycles above 4.3V, from 60% to 95% capacity retention during 1000 cycles above 4.3V, or from 60% to 95% capacity retention during 1000 cycles above 4.3V). In some embodiments, the battery can further include a separator disposed between the cathode and the anode.

[0068] In some embodiments, the anode can be an anode described above.

[0069] In some embodiments, the cathode can comprise a layered-structured cathode materials such as LiNio.6Mno.2Coo.2O2 (NMC622), LiNio.8Coo.1Mno.1O2 (NMC811), LiNii / 3Mm / 3Coi / 3O2 (NMC111), LiNio.5Mn1.5O4 (LNMO), LiNio.5Mm.5-xTix04, or LiNio.8Coo.i5Alo.o502 (NCA), or the like; cubic spinel cathode materials such as LiM2O4 (where M=Mn, Co, Ni, Al, Ti, Mg, combination thereof and the like); olivine materials such as LiMPO4 (where M=Fe, Co, Mn, combination thereof and the like); or any combination thereof.

[0070] In some embodiments, the cathode can comprise LiNio.6Mno.2Coo.2O2 (NMC622), LiNio.8Coo.1Mno.1O2 (NMC811), LiNii / 3Mni / 3Coi / 3O2 (NMC111), LiNio.5Mm.5O4 (LNMO), LiNio.5Mm.5-xTix04, LiNi0.8Co0.15Al0.05O2 (NCA), or any combination thereof.

[0071] In some embodiments, cathode can comprise LiNio.6Mno.2Coo.2O2 (NMC622), LiNio.8Coo.1Mno.1O2 (NMC811), LiNii / 3Mni / 3Coi / 3O2 (NMC111), LiNio.5Mm.5O4 (LNMO), LiNio.5Mm.5-xTix04, or LiNi0.8Co0.15Al0.05O2 (NCA).

[0072] In some embodiments, the cathode can be manganese rich. In some embodiments, the cathode can comprise a material represented by formula I:

[0073] Li l+z(Ni 1-x-yMnxCOy) l-zO2 wherein y is less than 0.12, x is greater than 0.5, and z is 0.13. In some embodiments, the electrode active material can be Li1.13Nio.28i25Mno.53125Coo.i875O2.13.

[0074] In some embodiments, the cathode can be nickel rich. In some embodiments, the cathode can comprise a material represented by formula IL

[0075] LiNi i-x-yMnxCoyO2 wherein x is less than 0.1; and y is less than 0.1.

[0076] In some embodiments, the cathode can comprise a material represented by Formula III:

[0077] LiNi1-xCoo.5xMno.5xO2 wherein x is 0.15 or 0.1.

[0078] In some embodiments, the cathode can comprise LiNio.ssCoo.twsMno.tnsCh, LiNi0.9Co0.05Mn0.05O2, or LiNio.5Mm.5-xTix04,LiNio.8Coo.i5Alo.o502, or any combination thereof.

[0079] In some embodiments, the cathode can comprise LiNio.85Coo.o75Mno.o7s02, LiNi0.9Co0.05Mn0.05O2, LiNio.5Mni.5-xTix04, orLiNio.8Coo.15Alo.05O2.

[0080] In some embodiments, the cathode can comprise a material represented by a formula Lii+bNic np-5CoYM5O2-zFz, where b ranges from 0.01 to 0.3, a ranges from 0 to 0.4, P ranges from 0.2 to 0.65, y ranges from 0 to 0.45, 5 ranges from 0 to 0.15 and z ranges from 0 to 0.2, and where M can be Mg, Zn, Al, Ga, B, Zr, Ti, Ca, Ce, Y, Nb or combinations thereof.

[0081] The batteries described herein can be incorporated in a variety of electronically powered or assisted devices, including transportation devices (e.g., electronic vehicles), computers, telecommunications devices (e.g., cell phones), cameras, radios, power tools, etc. The batteries can also be used in other energy storage applications.

[0082] EXAMPLES

[0083] The graphite anode active material, conductive agent (Super-P), Li6.7La3Zn.7Tao.3O12 (LLZT) solid-electrolyte powder, and PVdF binders were mixed in different proportions. In this example, LLZT powder was incorporated at different ratios (e.g., 1 - 10 wt%) as a Li- ion conducting additive in graphite anodes. The LLZT has high conductivity above 104s / cm at room temperature, which can assist the Li+ion’s rapid diffusion from the surface to the bulk of graphite. For example, after blending 2.5 wt% LLZT into graphite anode, the full-cell exhibited excellent discharge capacity under fast-charging conditions. Besides, as a moisture sensitivity material, an appropriate amount of LLZT contributes to consuming the proton and H2O in the electrolyte and limits the decomposition of LiPF6 into Hydrofluoric (HF) acid, suppressing the further HF corrodes the electrodes. This strategy is schematically illustrated in FIG. 1.

[0084] The SEM-EDS images of the fresh electrode (FIG. 2) demonstrated that the LLZT particles can evenly across the surface of graphite and form a dense protective layer with increased amounts of LLZT. The electrochemical performances (FIG. 3) can be correlated to the quantity of LLZT blended into the graphite anode. For example, the small amount of LLZT can effectively improve the Li+ions conductivity of the anode but cannot completely sheathe the surface of graphite or scavenge the moisture stored in the electrolyte. Meanwhile, excessive LLZT will disrupt contact between graphite particles and impede electron transport within anodes, thereby degrading their fast-charging capability.

[0085] The optimized amount of LLZT should offer a good balance between surface protection and electronic / ionic transport properties to improve the overall performance. In half-cells (i.e., using lithium metal anodes), the 2.5 wt% LLZT blended graphite anodes delivered superior 10 C-rate performance compared to the bare graphite anodes, as shown in FIG. 3.

[0086] In addition, high-voltage single-layer pouch cell (SLPC) data was obtained by pairing with NMC cathodes. After 400 cycles, the SLPC made with the bare graphite anode maintained 16.8% of its initial discharge capacity when the cell was cycled in a range of 3 V - 4.4 V at C / 3-rate at 25°C. Conventional SLPC made with NMC cathode and graphite anodes operates up to 4.2 V. At such high-voltage operation (4.4 V in this case), cells can deliver high specific capacity but suffer from severe capacity fading. In contrast, LLZT blended anodes offers superior cycle life at the high-voltage operation: 71.5% capacity retention after 400 cycles in the range of 3 V - 4.4 V at C / 3-rate at 25°C.

[0087] Post-mortem characterization including X-ray photoelectron spectroscopy (XPS, FIG. 4) shows that LLZT blended graphite anode has thinner SEI layer thickness; e.g., stronger C-C intensity (from carbon or PVdF binder) and C-F intensity (from PVdF) binder comparing with the bare graphite anode. At the same time, the LLZT blended graphite shows relatively low intensity of -COOR, an electrolyte decomposition products deposited on graphite surface. This result confirms that the LLZT passivates the surface of graphite and suppresses unwanted reactions, maintaining thinner passivation layer during the repeated battery cycles.

[0088] These anodes can offer significant advantages. For example, blended LLZT can form a passivation layer on the surface of graphite for suppressing the parasitic reactions and improving capacity retention of graphite full-cells. The inclusion of LLZT can also enhance Li+ion conductivity, which can promote the fast-charging application. Further, LLZT can act as a moisture scavenger, reducing the decomposition of LiPFe salt to form HF and inhibit the corrosion of electrode surfaces. These strategies can also reduce additional manufacturer processes and the corresponding cost. These strategies can provide a low-cost and easily implementable method to provide graphite anodes with improved cycle performance and fast charging capability for EV usage.

[0089] Additionally, similar improvement in electrochemical performance is observed when Si with LLZT is cycled at 25°C between 5mV and IV. In a further example, a nanosized Si anode active material, conductive agent (Super-P), Li6.7La3Zn.7Tao.3O12 (LLZT) solid-electrolyte powder, and polyacrylate binder were mixed in different proportions. LLZT powder was incorporated at different ratios (e.g., 1 - 5.0 wt%) as a Li-ion conducting additive in Si anodes. The LLZT has high conductivity above 104s / cm at room temperature, which can assist the rapid diffusion of Li+ions from the surface to the bulk of Si. For example, after blending 2.5 wt% LLZT into Si anode, the half-cell (using a Li-metal as the counter electrode) exhibited much improved specific capacity illustrated in FIG. 5. Besides, at the increased fast-charging rates, such as 1 C and 2.5 C, the Si anodes with 2.5 wt% LLZT delivered higher discharge capacity compared with the bare anode (i.e., LLZT free).

[0090] From half cell cycle life data of Si with various amount of LLZT added, a prolonged capacity retention period can be seen when 2.5wt% of LLZT is added. The cell continues to supply capacity for 30 cycles before experiencing failure, in contrast to the immediate capacity fade experienced by baseline condition and condition with excess LLZT added. Similar trend permeates for the fast-charging test, where the capacity reached by 2.5wt% LLZT Si anode is higher than other two cases tested at C / 20, C / 3 and 1C.

[0091] These results provide evidence that the inclusion of LLZT extend ionic conduction network in next generation anodes such as Si and enhance their battery performances.

[0092] The compositions and methods of the appended claims are not limited in scope by the specific compositions and methods described herein, which are intended as illustrations of a few aspects of the claims and any compositions and methods that are functionally equivalent are intended to fall within the scope of the claims. Various modifications of the compositions and methods in addition to those shown and described herein are intended to fall within the scope of the appended claims. Further, while only certain representative compositions and method steps disclosed herein are specifically described, other combinations of the compositions and method steps also are intended to fall within the scope of the appended claims, even if not specifically recited. Thus, a combination of steps, elements, components, or constituents may be explicitly mentioned herein; however, other combinations of steps, elements, components, and constituents are included, even though not explicitly stated.

Claims

WHAT IS CLAIMED IS:

1. An anode comprising a population of particles comprises an ionically conducting solid-electrolyte disposed on an anode material, intermixed with an anode material, or a combination thereof.

2. The anode of claim 1, wherein the population of particles comprising the ionically conducting solid-electrolyte is disposed on a surface of the anode material.

3. The anode of any of claims 1-2, wherein the population of particles comprising the ionically conducting solid-electrolyte is intermixed with a second population of particles comprising the anode material.

4. The anode of any of claims 1-3, wherein the population of particles comprising the ionically conducting solid-electrolyte is present in an amount of from 1 wt% to 10 wt%, based on the total weight of the anode.

5. The anode of any of claims 1-4, wherein the population of particles comprising the ionically conducting solid-electrolyte exhibits an average particle size of from 20 nm to 30 pm.

6. The anode of any of claims 1-6, wherein the population of particles comprising the ionically conducting solid-electrolyte have a spherical shape.

7. The anode of any of claims 1-6, wherein the ionically conducing solid-electrolyte comprises LivLasZnOn (LLZO), Lii.4Alo.4Tii.6(P04)3 (LATP), Lio.sLao.sTiCh (LLTO), LisPCh, Li2HPC>4, or Li6.75La3Zn.75Tao.250i2 (LLZT).

8. The anode of any of claims 1-7, wherein the anode material comprises graphite.

9. The anode of any of claims 1-8, wherein the anode further comprises binder, carbon conductive material, a passivation layer, or any combination thereof.

10. A method of making an anode, the method comprising: contacting a first population of particles comprising an ionically conducting solidelectrolyte with a second population of particles comprising an anode material.

11. The method of claim 10, wherein the first population of particles comprising the ionically conducting solid-electrolyte is present in an amount of from 1 wt% to 10 wt%, based on the total weight of the anode.

12. The method of any of claims 10-11, wherein the first population of particles exhibits an average particle size of from 20 nm to 30 pm.

13. The method of any of claims 10-12, wherein the second population of particles exhibits an average particle size of from 20 nm to 30 pm.

14. The method of any of claims 10-13, wherein the first population of particles exhibits an average particle size and the second population of particles exhibits an average particle size, and wherein the average particle size of the first population of particles is from 0.005 to 200 of the average particle size of the second population of particles.

15. The method of any of claims 10-14, wherein the first population of particles, the second population of particles, or any combination thereof have a spherical shape.

16. The method of any of claims 10-15, wherein the ionically conducing solidelectrolyte comprises LivLasZrcOn (LLZO), Lii.4Alo.4Tii.6(P04)3 (LATP), Lio.sLao.sTiCh (LLTO), LisPCh, Li2HPC>4, or Li6.75La3Zn.75Tao.250i2 (LLZT).

17. The method of any of claims 10-16, wherein the anode material comprises graphite.

18. The method of any of claims 10-17, wherein the anode material is in the form of a powder and wherein the ionically conducting solid-electrolyte is in the form of a powder; andwherein contacting the anode material with the ionically conducting solid-electrolyte comprises physically blending the ionically conducting solid-electrolyte and the anode material.

19. The method of claim 18, wherein the physical blending comprises mechanical mixing or dropcast mixing.

20. The method of any of claims 10-17, wherein contacting the anode material with the ionically conducting solid-electrolyte comprises wet chemical coating the ionically conducting solid-electrolyte on the anode material.

21. The method of claim 20, wherein the wet chemical coating comprises a sol-gel, hydrothermal, or solvothermal synthesis process.

22. The method of any of claims 10-17, wherein contacting the anode material with the ionically conducting solid-electrolyte comprises physical absorption of the ionically conducting solid electrolyte on the anode material.

23. The method of claim 22, wherein the physical absorption comprises an aerosol spray, a roll to roll deposition, casting, or a lamination process.

24. The method of any of claims 10-23, wherein the method further comprises a physical characterization step.

25. The method of claim 24, wherein the physical characterization is performed using microscopy, XRD, Raman spectroscopy, or a combination thereof.

26. A battery comprising: an anode and a cathode disposed in a housing; and an electrolyte disposed between the cathode and the anode providing an ionically conductive pathway between the anode and the cathode;wherein the anode comprises a population of particles comprises an ionically conducting solid-electrolyte disposed on an anode material, intermixed with an anode material, or a combination thereof; and wherein the ionically conducting solid-electrolyte is present in an amount effective such that the battery exhibits greater than 60% capacity retention during 1000 cycles above 4.3V.

27. The battery of claim 26, wherein the anode comprises an anode defined by any of claims 1-9.

28. The battery of any of claims 26-27, wherein the anode comprises an anode made by the method defined by any of claims 10-25.

29. The battery of any of claims 26-28, wherein the cathode comprises a layered structured cathode material.

30. The battery of any of claims 26-29, wherein the battery further comprises a separator disposed between the cathode and the anode.

31. An electronically powered or assisted device comprising a battery according to any of claims 26-30.

32. A device according to claim 31 that is fabricated as a transportation device, a computer, a telecommunications device, a camera, a radio, or a power tool.

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