Oxide solid electrolyte coated nickel-based positive electrode for sulfide all-solid-state batteries

Abstract

A sulfide all-solid-state battery and a method of forming an oxide electrolyte coated positive electrode are provided. The battery includes a nickel-based positive electrode, an electrolyte coating attached to the nickel-based positive electrode, a negative electrode, and a sulfide solid electrolyte. And the nickel-based positive electrode comprises LiNi < 1-x-y-z > Co < x > Mn < y > Al < z > O < 2 >. The electrolyte coating includes an inorganic oxide solid electrolyte including Li1 + nAlnTi2-n (PO4) 3 (LATP), where 1-x-y-z is greater than 0.2, x is greater than or equal to 0, y is greater than or equal to 0, z is greater than or equal to 0, and where n is between 0.2 and 0.5. The sulfide solid electrolyte transmits charged ions between the negative electrode and the nickel-based positive electrode.

Description

Technical Field

[0001] This disclosure relates to a sulfide-based all-solid-state battery, and more specifically, to a coated nickel-based cathode within a sulfide-based all-solid-state battery. Background Technology

[0002] Rechargeable batteries are known to be used in consumer electronics applications, ranging from small electronic devices like mobile phones to large electronic devices like laptops. Compared to older rechargeable batteries such as nickel-metal hydride, nickel-cadmium, or lead-acid batteries, modern rechargeable lithium-ion batteries maintain a relatively high energy density. The advantage of rechargeable lithium-ion batteries is that they can be fully or partially charged and discharged multiple times without retaining a memory effect. Furthermore, rechargeable lithium-ion batteries can be used in larger applications, such as electric and hybrid vehicles, because of their high power density, long cycle life, and ability to be formed into various shapes and sizes, effectively filling the available space in such vehicles.

[0003] Modern rechargeable lithium-ion batteries typically utilize organic liquid electrolytes to carry or conduct lithium cations (Li₂O₃) between the positive and negative electrode active materials. + To further improve battery performance, organic liquid electrolytes have been replaced by solid-state electrolytes (SSEs) in more modern batteries. Solid-state electrolytes can broaden the operating temperature range of rechargeable lithium-ion batteries and increase energy density. Rechargeable lithium-ion batteries with solid-state electrolytes are known as rechargeable all-solid-state lithium-ion batteries.

[0004] Depending on the combination and / or compatibility of electrode active materials and suitable solid electrolytes, all-solid-state batteries (ASSBs) have the potential to become the long-term, robust, and high-performance energy storage system for next-generation electric vehicles. In this regard, high-specific-capacity nickel-based cathodes combined with high-ionic-conductivity sulfide electrolytes are promising. However, the poor interfacial compatibility / stability between nickel-based solid oxides and sulfide electrolytes during repeated charge-discharge cycles leads to deterioration in interfacial performance and cell performance.

[0005] While existing methods and systems attempt to minimize the drawbacks of using high-specific-capacity nickel-based cathodes combined with high-ionic-conductivity sulfide electrolytes and can achieve their specific objectives, a need remains for novel and improved sulfide all-solid-state batteries. Therefore, a stable and efficient sulfide all-solid-state battery is required. Summary of the Invention

[0006] According to several aspects of this disclosure, a sulfide all-solid-state battery is provided. The sulfide all-solid-state battery includes a nickel-based positive electrode, an electrolyte coating attached to the nickel-based positive electrode, a negative electrode, and a sulfide solid electrolyte. The nickel-based positive electrode includes LiNi. 1-x-y-z Co xMn y Al z O2. The electrolyte coating comprises an inorganic oxide solid electrolyte, wherein the inorganic oxide solid electrolyte includes Li. 1+n Al n Ti 2-n (PO4)3(LATP), where 1-xyz is greater than 0.2, x is greater than or equal to 0, y is greater than or equal to 0, z is greater than or equal to 0, and n is between 0.2 and 0.5. The sulfide solid electrolyte transports charged ions between the negative electrode and the nickel-based positive electrode.

[0007] According to another aspect of this disclosure, the nickel-based cathode of the sulfide all-solid-state battery includes an active material comprising a rock salt layered oxide, spinel, polyanionic cathode, olivine cathode, or lithium transition metal oxide.

[0008] According to another aspect of this disclosure, the nickel-based cathode of the sulfide all-solid-state battery includes a conductive additive, which includes at least one of carbon black, graphite, graphene, graphene oxide, conductive carbon black Super P, acetylene black, carbon nanofibers, or carbon nanotubes.

[0009] According to another aspect of this disclosure, the nickel-based cathode of the sulfide all-solid-state battery includes an adhesive comprising at least one of polytetrafluoroethylene (PTFE), sodium carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyvinylidene fluoride (PVDF), nitrile rubber (NBR), styrene-ethylene-butene-styrene copolymer (SEBS), polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP), polyethylene oxide (PEO), polyacrylonitrile (PAN), polyacrylic acid (PAA), or styrene-butadiene-styrene copolymer (SBS).

[0010] According to another aspect of this disclosure, the nickel-based cathode of the sulfide all-solid-state battery has a particle size (D50) of 0.1 μm to 50 μm.

[0011] According to another aspect of this disclosure, the negative electrode of the sulfide all-solid-state battery comprises 30% to 98% by weight of negative electrode active material, 0% to 50% by weight of solid electrolyte, 0% to 30% by weight of conductive additives, and 0% to 20% by weight of binder.

[0012] According to another aspect of this disclosure, the negative electrode of the sulfide all-solid-state battery comprises carbonaceous material, silicon, silicon mixed with graphite, and Li4Ti5O. 12 At least one of a transition metal, a metal oxide, or a metal sulfide.

[0013] According to another aspect of this disclosure, the thickness of the negative electrode of the sulfide all-solid-state battery is from 10 μm to 400 μm.

[0014] According to another aspect of this disclosure, in the sulfide all-solid-state battery, the electrolyte coating on the surface of the nickel-based positive electrode has a coverage of 20% to 100%.

[0015] According to another aspect of this disclosure, in the sulfide all-solid-state battery, the electrolyte coating accounts for 0.1% to 20% by weight of the nickel-based cathode.

[0016] According to another aspect of this disclosure, in the sulfide all-solid-state battery, the thickness of the electrolyte coating is from 5 μm to 200 μm.

[0017] According to another aspect of this disclosure, in the sulfide all-solid-state battery, the electrolyte coating includes at least one of garnet-type oxide electrolyte, perovskite-type oxide electrolyte, NASICON-type oxide, LISICON-type oxide, metal-doped oxide, or heterovalent substituted oxide solid electrolyte.

[0018] According to another aspect of this disclosure, in the sulfide all-solid-state battery, the electrolyte coating includes at least one of a quasi-binary sulfide, a quasi-ternary sulfide, or a quasi-quaternary sulfide.

[0019] According to another aspect of this disclosure, the sulfide all-solid-state battery further includes a filler comprising at least one of oxide particles, a polymer backbone, polyethylene (PE), or a lithium salt.

[0020] According to several aspects of this disclosure, a method for forming a positive electrode coated with an oxide electrolyte is provided. The method includes preparing an electrolyte coating and coating a nickel-based positive electrode with the electrolyte coating. The electrolyte coating comprises an inorganic oxide solid electrolyte, said inorganic oxide solid electrolyte comprising Li 1+n Al n Ti 2-n (PO4)3(LATP). Nickel-based cathodes include LiNi. 1-x-y-z Co x Mn y Al z O2. Additionally, 1-xyz is greater than 0.2, x is greater than or equal to 0, y is greater than or equal to 0, and z is greater than or equal to 0, where n is between 0.2 and 0.5.

[0021] According to another aspect of this disclosure, a method for preparing an electrolyte coating includes mixing electrolyte starting materials such as LiNO3, Al(NO3)3·9H2O, Ti(OCH(CH3)2)4 and H3PO4 with a solvent to form a precursor solution, adding a nickel-based cathode material to the precursor solution and mixing to form a coating solution, evaporating and drying the coating solution to form an electrolyte coating, and sintering the electrolyte coating in air at 700°C to 950°C for 2 to 12 hours.

[0022] According to another aspect of this disclosure, a method for preparing an electrolyte coating includes mixing electrolyte starting materials of Li₂CO₃, Al₂NO₃, TiO₂, and NH₂H₂PO₄, wherein the electrolyte starting materials are mixed according to the stoichiometric ratio of LATP, the electrolyte starting materials are ball-milled, the electrolyte starting materials are sintered to form LATP, and the LATP is ground using a pulverizer to reduce the LATP particle size. The method for preparing the electrolyte coating further includes mechanically fusing LATP to a nickel-based cathode material using a mechanical fusion machine for 10 to 120 minutes, and heating the LATP and the nickel-based cathode material in air at 400°C to 800°C for 1 to 12 hours.

[0023] According to another aspect of this disclosure, preparing the electrolyte coating includes sintering the electrolyte starting material in air at 700°C to 950°C for 2 to 4 hours.

[0024] According to several aspects of this disclosure, a sulfide all-solid-state battery is provided. The battery includes a nickel-based positive electrode, an electrolyte coating attached to the nickel-based positive electrode, a lithium or lithium-based negative electrode, and a sulfide solid electrolyte. The nickel-based positive electrode includes LiNi. 1-x-y- z Co x Mn y Al z O2. The electrolyte coating includes inorganic oxide solid electrolytes, including Li. 1+ n Al n Ti 2-n (PO4)3, wherein 1-xyz is greater than 0.2, x is greater than or equal to 0, y is greater than or equal to 0, z is greater than or equal to 0, and n is between 0.2 and 0.5. The thickness of the negative electrode is between 10 micrometers and 400 micrometers (μm). The sulfide solid electrolyte transports charged ions between a lithium or lithium-based negative electrode and a nickel-based positive electrode, and the thickness of the electrolyte coating is between 5 μm and 200 μm. The sulfide solid electrolyte comprises fillers, binders, and at least one of quasi-binary sulfides, quasi-ternary sulfides, or quasi-quaternary sulfides.

[0025] According to another aspect of this disclosure, the filler for a sulfide all-solid-state battery includes at least one of oxide particles, a polymer skeleton, polyethylene (PE), or a lithium salt.

[0026] Further applicability of this disclosure will become apparent from the detailed description provided below. It should be understood that the specification and specific embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure.

[0027] The above-described features and advantages, as well as other features and advantages, of the currently disclosed systems and methods will become apparent when taken in conjunction with the accompanying drawings and the detailed description including the claims and embodiments. Attached Figure Description

[0028] This disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0029] Figure 1 This is a perspective view illustrating an embodiment of an all-solid-state battery according to the present disclosure, the all-solid-state battery comprising a nickel-based positive electrode, a negative electrode, and a sulfide solid electrolyte having an inorganic oxide solid electrolyte.

[0030] Figure 2 This illustrates the use of, according to this disclosure, as follows Figure 1 The flowchart shows a method for coating a nickel-based cathode with an inorganic oxide solid electrolyte. Detailed Implementation

[0031] Reference will now be made in detail to several embodiments of the present disclosure illustrated in the accompanying drawings. Wherever possible, the same or similar reference numerals are used in the drawings and description to denote the same or similar components or steps. The following description is merely exemplary in nature and is not intended to limit the present disclosure, its application, or its uses.

[0032] This paper discloses a cathode for sulfide-based all-solid-state batteries, achieved by coating an inorganic oxide solid electrolyte onto a nickel-based cathode material, with the aim of stabilizing the cathode / sulfide interface. Nickel-based solid oxides are currently the benchmark cathodes for conventional lithium-ion batteries due to their high storage capacity / energy, and may be crucial for the use of ASSBs. However, interfacial compatibility or stability with the sulfide electrolyte presents challenges.

[0033] Some detrimental interfacial behaviors between Ni-based cathodes and sulfide electrolytes include contact loss, Ni… 4+ The strong oxidation and phase transition of Ni. The structural instability of the highly delithiated cathode may lead to contact loss. Furthermore, Ni... 4+The strong oxidation process causes oxygen to be released from the crystal lattice, and the main structure is destroyed in a highly delithiated state. Furthermore, a phase transition occurs due to oxygen release and cation mixing during charge-discharge cycles. This poor interfacial compatibility and stability leads to capacity degradation and a continuous increase in resistance. The current solution is to coat the cathode with a LiNb3O layer. However, the LiNb3O layer exhibits poor lithium-ion conductivity.

[0034] Figure 1 A schematic diagram of a sulfide all-solid-state battery 10 (or “battery cell”) is shown. Multiple solid-state battery cells 10 can be folded or stacked to form a rechargeable all-solid-state battery and achieve desired battery voltage, power, and energy. The sulfide all-solid-state battery 10 includes a positive electrode or nickel-based positive electrode 12, a negative electrode or negative electrode 14, and a sulfide solid electrolyte 16.

[0035] The nickel-based cathode 12 includes a cathode active material 13 (or cathode active material particles 13), an electrolyte coating 18, conductive additives, and / or a binder. Preferably, the nickel-based cathode 12 includes about 30 wt.% to about 98 wt.% of the cathode active material 13, about 0 wt.% to about 30 wt.% of the conductive additives, and about 0 wt.% to about 20 wt.% of the binder.

[0036] The positive electrode active material 13 may include any suitable material, such as high-voltage oxides, surface-coated high-voltage cathode materials, doped high-voltage cathode materials, rock-salt layered oxides, spinel, polyanionic cathodes, olivine cathodes, lithium transition metal oxides, or mixtures thereof. In one embodiment, the positive electrode active material 13 includes LiNi. 1-x-y- z Co x Mn y Al z O2, LiNi 0.5 Mn 1.5 LiNi coated with O4 and LiNbO3 0.5 Mn 1.5 O4, LiCoO2, LiNi x Mn y Co 1-x-y O2, LiNi x Mn 1-x O2, Li 1+x MO2, LiMn2O4, LiV2(PO4)3, or mixtures thereof, wherein 1-xyz is greater than 0.2, x is greater than or equal to 0, y is greater than or equal to 0, and z is greater than or equal to 0, and wherein n is between 0.2 and 0.5. In one specific embodiment, the nickel-based cathode 12 comprises LiNi0.5 Co 0.2 Mn 0.3 The positive electrode active material 13 is O2 (NCM523). Additionally, the nickel-based positive electrode 12 may include a particle size (D50) of about 0.1 μm to about 50 μm in diameter and may be single crystals and / or secondary particles. In this document, the term "about" is known to those skilled in the art. Alternatively, the term "about" may be interpreted as ±0.5% by weight. The nickel-based positive electrode 12 can be prepared using wet coating processes, dry film processes, dry powder coating processes, etc.

[0037] The conductive additives in the positive electrode layer can include any suitable materials, such as carbon black, graphite, graphene, graphene oxide, conductive carbon black Super P, acetylene black, carbon nanofibers, carbon nanotubes, and other electronically conductive additives.

[0038] The binder for the positive electrode layer may include poly(tetrafluoroethylene) (PTFE), sodium carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyvinylidene fluoride (PVDF), nitrile rubber (NBR), styrene-ethylene-butene-styrene copolymer (SEBS), polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP), polyethylene oxide (PEO), polyacrylonitrile (PAN), polyacrylic acid (PAA), or styrene-butadiene-styrene copolymer (SBS), etc.

[0039] refer to Figure 1 The nickel-based cathode 12 includes an electrolyte coating 18 attached to the nickel-based cathode active material 13 (an oxide electrolyte-coated cathode). The electrolyte coating 18 includes an inorganic oxide solid electrolyte, such as Li. 1+n Al n Ti 2-n (PO4)3(LATP), where x is greater than or equal to 0, y is greater than or equal to 0, z is greater than or equal to 0, and n is between 0.2 and 0.5. The electrolyte coating 18 may include a garnet-type oxide electrolyte, a perovskite-type oxide electrolyte, a NASICON-type oxide, a LISICON-type oxide, a metal-doped oxide, or anisovalent substituted oxide solid electrolyte. The electrolyte coating 18 may comprise about 0.1 wt.% to about 20 wt.% of the nickel-based cathode 12. In one specific embodiment, it contains Li 1.3 Al 0.3 Ti 1.7 The electrolyte coating of (PO4)3(LATP) accounts for 18% of the nickel-based positive electrode active material particles, such as LiNi. 0.5 Co 0.2 Mn 0.3The content of O2 (NCM523) is approximately 1 wt.%. In this document, the term "approximately" is known to those skilled in the art. Alternatively, the term "approximately" may be interpreted as ±0.5% by weight. Furthermore, the electrolyte coating 18 provides 20% to 100% coverage of the surface of the nickel-based cathode active material particles 13.

[0040] The use of LATP solid electrolyte coating 18 as a NASICON-type lithium-ion conductor enables faster lithium-ion conduction at the cathode / sulfide electrolyte interface compared to other commonly used coatings. Furthermore, LATP solid electrolyte coating 18 exhibits approximately 4.2 volts (relative to Li / Li). + The high electrochemical oxidation potential of the LATP solid electrolyte coating 18 prevents oxidative decomposition of the electrolyte coating 18 material, suppresses interfacial interactions, and stabilizes the interface between the nickel-based cathode active material particles 13 and the sulfide electrolyte coating 18. Furthermore, the LATP solid electrolyte coating 18 is inherently stable, thus improving thermal stability when applied to the surface of the nickel-based cathode 12.

[0041] like Figure 1 As shown, the all-solid-state battery 10 includes a negative electrode 14. The negative electrode 14 comprises about 30 wt.% to about 98 wt.% of a negative electrode active material, about 0 wt.% to about 50 wt.% of a solid electrolyte, about 0 wt.% to about 30 wt.% of a conductive additive, and about 0 wt.% to about 20 wt.% of a binder. The negative electrode 14 may have a thickness of about 10 micrometers (μm) to about 400 μm. In this document, the term "about" is known to those skilled in the art. Alternatively, the term "about" may be interpreted as ±0.5 wt%. The negative electrode active material may include carbonaceous materials (e.g., graphite, hard carbon, and soft carbon), silicon, silicon-graphite mixtures, Li4Ti5O, etc. 12 Transition metals (e.g., Sn), metal oxides or sulfides (e.g., TiO2, FeS), and other lithium-accepting anode materials, etc.

[0042] The conductive additives for the negative electrode 14 may include any suitable materials, such as carbon black, graphite, graphene, graphene oxide, conductive carbon black Super P, acetylene black, carbon nanofibers, carbon nanotubes and other electronically conductive additives.

[0043] The binder for the negative electrode 14 may include polytetrafluoroethylene (PTFE), sodium carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyvinylidene fluoride (PVDF), nitrile rubber (NBR), styrene-ethylene-butene-styrene copolymer (SEBS), polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP), polyethylene oxide (PEO), polyacrylonitrile (PAN), polyacrylic acid (PAA), or styrene-butadiene-styrene copolymer (SBS), etc.

[0044] like Figure 1 As shown, the all-solid-state battery 10 includes a sulfide solid electrolyte membrane containing a sulfide solid electrolyte 16. The sulfide solid electrolyte 16 transports charged ions between the negative electrode 14 and the nickel-based positive electrode 12. The sulfide solid electrolyte is derived from an oxide solid electrolyte and is formed by replacing oxygen ions with sulfide ions. Due to its lower electronegativity, the bond strength between sulfide ions and lithium ions is less than that between oxygen ions and lithium ions, which may result in more freely moving lithium ions. In addition, the radius of a sulfide ion is larger than that of an oxygen ion. Therefore, the sulfide solid electrolyte can provide a larger migration channel for lithium ions, which facilitates lithium ion migration.

[0045] The sulfide solid electrolyte 16 may include quasi-binary sulfides (e.g., Li2S-P2S5 system (Li8PS4, Li7P3S)). 11 and Li 9.6 P3S 12 ), Li2S-SnS2 system (Li4SnS4), Li2S-SiS2 system, Li2O-Li2S-P2S5 system, Li2S-B2S3 system, Li2S-Ga2S3 system, Li2S-P2S3 system, or Li2S-Al2S3 system); quasi-ternary sulfides (e.g., Li2O-Li2S-P2S5 system, Li2S-P2S5-P2O5 system, Li2-P2S5-GeS2 system (e.g., Li 8.25 Ge 0.25 P 0.75 S4, Li 10 GeP2S 12 Li₂S-P₂S₅-LiX (X = F, Cl, Br, I) systems (e.g., LiS₆-P₆Br, Li₆PS₅Cl, Li₇P₂S₈I, Li₄PS₄I), and Li₂S-As₂S₅-SnS₂ systems (e.g., Li₂S₅-P₂S₅-LiX) ...�Br, Li₆PS₅Cl, Li₇P� 8.833 Sn 0.833 As 0.166 S4), Li2S-P2S5-Al2S3 system, Li2S-LiX-SiS2 (X=F, Cl, Br, I) system (e.g. 0.4LiI0.6Sn2S4, Li 11 Si2PS 12 ); or quasi-quaternary sulfides (e.g., Li₂O-Li₂S-P₂S₅-P₂O₅ system, Li 0.54 Si 1.74 P 1.44 S 11.7 Cl 0.3 Li7P 2.9 Mn 0.1 S10.7 I 0.3 Or Li 10.35 [Sn 0.27 Si 1.08 ]P 1.65 S 12 ).

[0046] Sulfide solid electrolyte membranes may contain fillers. Fillers may include oxide particles (e.g., SiO2, Al2O3, TiO2, or ZrO2), polymer backbones (e.g., polypropylene (PP), polyethylene (PE)), lithium salts (e.g., LiTFSI, Li4BF, etc.), etc.

[0047] Sulfide solid electrolyte membranes may contain adhesives. Adhesives may include polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP), polytetrafluoroethylene (PTFE), sodium carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), nitrile rubber, butadiene rubber (NBR), styrene-ethylene-butene-styrene copolymer (SEBS), polyethylene oxide (PEO), polyvinylpyrrolidone (PVP), polyvinyl alcohol, or polyacrylic acid (PAA), etc.

[0048] refer to Figure 2 This illustrates a method 100 for forming a nickel-based cathode 12 coated with an oxide electrolyte according to the present disclosure. The method begins at block 102. Block 102 depicts the preparation of an electrolyte coating 18. The electrolyte coating 18 comprises an inorganic oxide solid electrolyte, which includes Li... 1+n Al n Ti 2-n (PO4)3(LATP), where x is greater than or equal to 0, y is greater than or equal to 0, and z is greater than or equal to 0. The n value is equal to 0, and n is between 0.2 and 0.5.

[0049] Boxes 104 to 110 depict a first embodiment of preparing an electrolyte coating, comprising a simple sol-gel method followed by a calcination process. Box 104 depicts mixing electrolyte starting materials LiNO3, Al(NO3)3·9H2O, Ti(OCH(CH3)2)4, and H3PO4 with a solvent to form a precursor solution. In one embodiment, the solvent comprises anhydrous ethanol. In one embodiment, the precursor solution comprises LiNO3 (e.g., 1.3 mol (M)), Al(NO3)3·9H2O (e.g., 0.3 M), Ti(OCH(CH3)2)4 (e.g., 1.7 M), and H3PO4 (e.g., 3.0 M). A mixer, such as a ribbon mixer, can be used to mix the starting materials. It should be understood that a variety of other mixers can be used to mix the electrolyte starting materials.

[0050] Box 106 depicts adding a nickel-based cathode material to a precursor solution and mixing it to form a coating solution. The dosage of the coating solution determines the coating ratio of LATP on the nickel-based cathode 12 (e.g., 1 wt.%). A mixer, such as a ribbon mixer, can be used to mix the nickel-based cathode material and the precursor solution. It should be understood that a variety of other mixers can be used to mix the nickel-based cathode material and the precursor solution to form the coating solution.

[0051] Box 108 depicts evaporating and drying the coating solution to form an electrolyte coating. In one embodiment, an evaporator and / or a dryer may be used for the steps shown in box 108. Evaporating and drying the coating solution ensures that a uniform coating can be applied to the surface of the cathode particles.

[0052] Box 110 depicts the sintering of the electrolyte coating. For example, the electrolyte coating can be sintered or calcified in air at 700°C to 950°C for 2 to 12 hours. A sintering furnace or other types of furnace can be used to sinter the electrolyte coating. It should be understood that the electrolyte coating can be sintered at a variety of temperatures and times.

[0053] Boxes 112 to 122 depict a second embodiment for preparing an electrolyte coating, which includes a simple mechanical fusion method. Box 112 depicts an electrolyte starting material consisting of a mixture of Li₂CO₃, Al₂NO₃, TiO₂, and NH₂H₂PO₄ (LATP), wherein the electrolyte starting materials are mixed according to the stoichiometric ratio of LATP. The electrolyte starting materials can be mixed in a dry mixer or other mixers capable of mixing dry materials.

[0054] Box 114 depicts ball milling of electrolyte starting materials. Electrolyte starting materials can be milled using a ball mixer or other mixers capable of mixing them.

[0055] Box 116 depicts sintering the electrolyte starting material to form LATP. For example, the electrolyte coating can be sintered or calcified in air at 700°C to 950°C (e.g., 900°C) for 2 to 12 hours (e.g., 4 hours). A sintering furnace or other type of furnace can be used to sinter the electrolyte coating. It should be understood that the electrolyte coating can be sintered at a variety of temperatures and times. In some cases, a pre-prepared powder including the LATP starting material can be used and steps in boxes 112 to 116 can be skipped. In these cases and in this embodiment of preparing the electrolyte coating, box 102 will instead begin with box 118.

[0056] Box 118 depicts grinding LATP using a pulverizer to reduce the LATP particle size. Grinding LATP using a pulverizer can include reducing the particle size of LATP powder to hundreds of nanometers, such as particles with an average size of about 400 nanometers (nm).

[0057] Box 120 describes the mechanical fusion of LATP to nickel-based cathode material using a mechanical fusion machine for 10 to 120 minutes.

[0058] Box 122 depicts heating LATP and nickel-based cathode material in air at 400°C to 800°C for 1 hour to 12 hours. The resulting heated LATP and nickel-based cathode material forms the final material for coating the nickel-based cathode 12. Then, boxes 110 or 122 proceed to box 124.

[0059] Box 124 describes coating nickel-based cathode active material particles 13 with an electrolyte coating 18, wherein the nickel-based cathode active material particles 13 contain LiNi 1-x-y-z Co x Mn y Al z O2. The nickel-based positive electrode active material having the electrolyte coating 18 can be used to prepare the nickel-based positive electrode layer 12 by a wet coating process, a dry film process, a dry powder coating process, etc. The resulting nickel-based positive electrode 12 contains about 30 wt.% to about 98 wt.% of positive electrode active material particles 13, about 0 wt.% to about 30 wt.% of conductive additives, and about 0 wt.% to 20 wt.% of binder.

[0060] Compared to existing solid-state lithium batteries or other lithium batteries, the all-solid-state battery 10 and nickel-based cathode 12 disclosed herein are advantageous and beneficial. The electrolyte coating 18 enables lithium ions to conduct more rapidly at the cathode / sulfide electrolyte interface than with other commonly used coatings. Furthermore, the LATP solid electrolyte coating 18 exhibits a high electrochemical oxidation potential, which prevents oxidative decomposition of the electrolyte coating 18 material, suppresses interfacial interactions, and stabilizes the interface between the nickel-based cathode 12 and the sulfide electrolyte coating 18. The LATP solid electrolyte coating 18 is inherently stable, thus improving thermal stability.

[0061] This description is merely illustrative in nature and is in no way intended to limit the scope of this disclosure, its application, or its use. The broad teachings of this disclosure can be implemented in many forms. Therefore, while this disclosure includes specific embodiments, its true scope should not be so limited, as other modifications will become apparent upon examination of the drawings, description, and appended claims.

Claims

1. A sulfide all-solid-state battery, comprising: Nickel-based cathode, wherein the nickel-based cathode includes LiNi 1-x-y-z Co x Mn y Al z O2; An electrolyte coating attached to the nickel-based cathode, wherein the electrolyte coating comprises a Li-containing layer. 1+n Al n Ti 2-n An inorganic oxide solid electrolyte of (PO4)3(LATP), wherein 1-xyz is greater than 0.2, x is greater than or equal to 0, y is greater than or equal to 0, and z is greater than or equal to 0, and n is between 0.2 and 0.5; Negative electrode; and A sulfide solid electrolyte, wherein the sulfide solid electrolyte transports charged ions between the negative electrode and the nickel-based positive electrode.

2. The sulfide all-solid-state battery according to claim 1, wherein, The nickel-based cathode comprises an active material, which includes at least one of rock salt layered oxide, spinel, polyanionic cathode, olivine cathode, or lithium transition metal oxide.

3. The sulfide all-solid-state battery according to claim 1, wherein, The nickel-based cathode contains a conductive additive, which includes at least one of carbon black, graphite, graphene, graphene oxide, conductive carbon black Super P, acetylene black, carbon nanofibers, or carbon nanotubes.

4. The sulfide all-solid-state battery according to claim 1, wherein, The nickel-based cathode includes an adhesive comprising at least one of polytetrafluoroethylene (PTFE), sodium carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyvinylidene fluoride (PVDF), nitrile rubber (NBR), styrene-ethylene-butene-styrene copolymer (SEBS), polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP), polyethylene oxide (PEO), polyacrylonitrile (PAN), polyacrylic acid (PAA), or styrene-butadiene-styrene copolymer (SBS).

5. The sulfide all-solid-state battery according to claim 1, wherein the particle size (D50) of the nickel-based cathode is from 0.1 μm to 50 μm.

6. The sulfide all-solid-state battery according to claim 1, wherein, The negative electrode comprises 30% to 98% by weight of negative electrode active material, 0% to 50% by weight of solid electrolyte, 0% to 30% by weight of conductive additives, and 0% to 20% by weight of binder.

7. The sulfide all-solid-state battery according to claim 1, wherein the negative electrode comprises carbonaceous material, silicon, silicon mixed with graphite, and Li4Ti5O. 12 At least one of a transition metal, a metal oxide, or a metal sulfide.

8. The sulfide all-solid-state battery according to claim 1, wherein the thickness of the negative electrode is from 10 μm to 400 μm.

9. The sulfide all-solid-state battery according to claim 1, wherein, The electrolyte coating on the surface of the nickel-based cathode has a coverage of 20% to 100%.

10. The sulfide all-solid-state battery according to claim 1, wherein the electrolyte coating comprises 0.1% to 20% by weight of the nickel-based cathode.

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