Integrated solid-state battery unit and integrated solid-state battery

Abstract

The invention belongs to the technical field of secondary batteries, and particularly relates to an integrated solid-state battery unit and an integrated solid-state battery. The integrated solid-state battery unit comprises a combination formed by stacking at least two of an integrated positive electrode, an integrated negative electrode and an integrated solid-state electrolyte, compared with the prior art, the integrated solid-state battery unit is simple to prepare and low in cost, and when the integrated solid-state battery unit is applied to an integrated solid-state battery, the service life of the integrated solid-state battery unit is prolonged. The problem of a solid-solid interface in the solid-state battery is also solved, and the solid-state battery with better electrochemical performance is provided.

Description

Technical Field

[0001] This invention belongs to the field of secondary battery technology, specifically relating to an integrated solid-state battery cell and an integrated solid-state battery. Background Technology

[0002] After liquid lithium-ion batteries were industrialized in 1991, they were initially used in consumer batteries, where the capacity of a single cell was relatively low and the cycle life was relatively short. However, with the increasingly widespread application of lithium-ion battery technology in power and energy storage, people have placed increasingly higher demands on battery safety, energy density, and cycle life. However, the electrolyte in liquid lithium-ion batteries is liquid, highly reactive, unstable at high temperatures, easily decomposes, and is flammable. It also undergoes many side reactions with the positive and negative electrodes, affecting battery life and potentially leading to safety issues. Therefore, researchers hope to replace the liquid electrolyte with a solid-state electrolyte, developing solid-state batteries to improve safety performance, extend cycle life, use higher energy density positive and negative electrodes to increase energy density, and reduce battery system costs through methods such as internal series connection.

[0003] Currently, industry reports on solid-state battery research and applications mainly fall into three categories: The first category largely follows the current process route for liquid lithium-ion batteries, utilizing oxides, polymers, or composite electrolytes of oxides and polymers, and adding a small amount of liquid small molecules for in-situ polymerization to prepare a semi-solid electrolyte. Existing positive and negative electrodes are then modified to create a semi-solid battery. The second category primarily uses solid sulfides or oxides as the solid electrolyte and assembles them with modified positive and negative electrodes to form a fully solid-state battery. However, this often requires an external pressure of 5 to 7 MPa, making it difficult to use. The third category is somewhat similar to the second, but for the positive electrode, negative electrode, and electrolyte, at least one or all of them must undergo high-temperature sintering to achieve better contact between the three components, thus solving the problem of requiring pressure for use. Even with sintering, many voids and point contacts still exist inside the positive electrode, negative electrode, and electrolytic material, as well as between their interfaces. This still cannot effectively solve the solid-solid interface and kinetic problems, affecting temperature performance, rate performance, cycle life, etc. Moreover, the process is complex and costly.

[0004] Therefore, under the current technological background, there is an urgent need to develop an integrated solid-state battery cell to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide an integrated solid-state battery cell to address the shortcomings of existing technologies, thereby solving problems such as poor solid-solid interface contact, difficult operation, and high cost within solid-state batteries.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] An integrated solid-state battery cell includes a combination of at least two of an integrated positive electrode, an integrated negative electrode, and an integrated solid electrolyte stacked together.

[0008] The integrated solid electrolyte is an integrated unit formed by processing large-size solid electrolyte materials of millimeter size and above, and its chemically continuous size in at least one direction in three-dimensional space is a, where a satisfies the relationship: a≥0.5mm;

[0009] The integrated negative electrode active material unit is an integrated unit formed by processing and cutting large-size negative electrode materials of millimeter size and above. Its chemically continuous dimension in at least one direction in three-dimensional space is b, and b satisfies the relationship: b≥0.5mm.

[0010] The integrated positive electrode active material unit is an integrated unit formed by processing large-size positive electrode materials of millimeter size and above. Its chemically continuous size in at least one direction in three-dimensional space is c, and c satisfies the relationship: c≥0.5mm.

[0011] Preferably, the preparation method of the integrated positive electrode active material unit, the integrated negative electrode active material unit, or the integrated solid electrolyte includes the following steps:

[0012] Step 1: Fabricate positive electrode active material particles, negative electrode active material particles, or solid electrolyte particles into large-size materials at the millimeter level or above;

[0013] Step 2: Process the large-sized material into an integrated material unit.

[0014] Preferably, the integrated positive electrode includes a positive current collector and an integrated positive active material unit disposed on at least one surface of the positive current collector; the integrated negative electrode includes a negative current collector and an integrated negative active material unit disposed on at least one surface of the negative current collector.

[0015] Preferably, at least one of the integrated positive electrode, integrated negative electrode and integrated solid electrolyte is provided with a surface modification layer.

[0016] Preferably, the integrated positive electrode, integrated negative electrode, and integrated solid electrolyte are connected by bonding, pressurization, heating, or sintering.

[0017] Preferably, the surface modification layer of the integrated solid electrolyte includes a negative electrode active material or a positive electrode active material. The positive electrode active material includes one of lithium-ion battery positive electrode active materials, sodium-ion battery positive electrode active materials, and potassium-ion battery positive electrode active materials. The negative electrode active material is one of carbon negative electrode materials and non-carbon negative electrode materials.

[0018] Preferably, the processing method is cutting, molding, or other processing methods.

[0019] Preferably, the positive current collector includes aluminum foil and composite aluminum foil or other positive current collector materials, and the negative current collector includes copper foil, aluminum foil, composite copper foil and composite aluminum foil or other negative current collector materials.

[0020] Preferably, at least one integrated positive electrode active material unit is disposed on at least one surface of the positive electrode current collector; at least one integrated negative electrode active material unit is disposed on at least one surface of the negative electrode current collector.

[0021] This application also provides an integrated solid-state battery, including at least one of the above-described integrated solid-state battery cells.

[0022] Preferably, the integrated solid-state batteries are connected in series, in parallel, or in a series-parallel connection.

[0023] The beneficial effects of the present invention are as follows: The integrated solid-state battery cell provided by the present invention includes at least two of the following: an integrated positive electrode, an integrated negative electrode, and an integrated solid electrolyte. Compared with the prior art, the integrated solid-state battery cell is simple to prepare and has low cost. When applied to integrated solid-state batteries, it also solves the solid-solid interface problem inside solid-state batteries and provides solid-state batteries with better electrochemical performance. Attached Figure Description

[0024] Figure 1 This is one of the schematic diagrams of an integrated solid-state battery cell structure in one embodiment of the present invention;

[0025] Figure 2 This is a second schematic diagram of an integrated solid-state battery cell structure in one embodiment of the present invention;

[0026] Figure 3 This is the third schematic diagram of the integrated solid-state battery cell structure in one embodiment of the present invention;

[0027] Figure 4 This is the fourth schematic diagram of the integrated solid-state battery cell structure in one embodiment of the present invention;

[0028] Figure 5 This is the fifth schematic diagram of the integrated solid-state battery cell structure in one embodiment of the present invention;

[0029] Figure 6 This is the sixth schematic diagram of the integrated solid-state battery cell structure in one embodiment of the present invention;

[0030] Figure 7 This is the seventh schematic diagram of the integrated solid-state battery cell structure in one embodiment of the present invention;

[0031] Among them, 1. Positive current collector; 2. Integrated positive active material unit; 3. Integrated solid electrolyte; 4. Negative current collector; 5. Integrated negative active material unit. Detailed Implementation

[0032] The present invention and its beneficial effects will be further described in detail below with reference to specific embodiments and accompanying drawings. However, the specific embodiments of the present invention are not limited thereto.

[0033] In the description of this invention, unless otherwise expressly specified and limited, the term "comprising" is an open-ended term and should be interpreted as "including but not limited to".

[0034] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "set up" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0035] Furthermore, the reference to "embodiment" in this invention means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0036] like Figure 1 As shown, an integrated solid-state battery cell is provided, comprising a combination of at least two of an integrated positive electrode, an integrated negative electrode, and an integrated solid electrolyte stacked together.

[0037] An integrated solid electrolyte is an integrated unit formed by processing large-size solid electrolyte materials at the millimeter level or above. Its chemically continuous dimension in at least one direction in three-dimensional space is a, and a satisfies the relationship: a≥0.5mm. a=0.8mm, a=1mm, a=2mm, a=3mm, a=5mm, a=7mm, a=9mm, a=15mm, a=19mm, a=22mm, a=23mm, a=34mm, a=39mm, a=43mm, a=47mm, a=53mm, a=55mm, a=59 mm, a=63mm, a=73mm, a=83mm, a=93mm, a=103mm, a=113mm, a=123mm, a=133mm, a=143mm, a=153mm, a=163mm, a=173mm, a=183mm, a=193mm, a=203mm.

[0038] The integrated negative electrode active material unit is an integrated unit formed by processing large-size negative electrode materials of millimeter size and above. Its chemically continuous size in at least one direction in three-dimensional space is b, and b satisfies the relationship: b≥0.5mm. b=0.8mm, b=1mm, b=2mm, b=3mm, b=5mm, b=7mm, b=9mm, b=15mm, b=19mm, b=22mm, b=23mm, b=34mm, b=39mm, b=43mm, b=47mm, b=53mm, b=55mm, b=59 mm, b=63mm, b=73mm, b=83mm, b=93mm, b=103mm, b=113mm, b=123mm, b=133mm, b=143mm, b=153mm, b=163mm, b=173mm, b=183mm, b=193mm, b=203mm.

[0039] An integrated positive electrode active material unit is an integrated unit formed by processing large-size positive electrode materials of millimeter size and above. Its chemically continuous size in at least one direction in three-dimensional space is c, and c satisfies the relationship: c≥0.5mm. c=0.8mm, c=1mm, c=2mm, c=3mm, c=5mm, c=7mm, c=9mm, c=15mm, c=19mm, c=22mm, c=23mm, c=34mm, c=39mm, c=43mm, c=47mm, c=53mm, c=55mm, c=59 mm, c=63mm, c=73mm, c=83mm, c=93mm, c=103mm, c=113mm, c=123mm, c=133mm, c=143mm, c=153mm, c=163mm, c=173mm, c=183mm, c=193mm, c=203mm.

[0040] In one embodiment of this application, a method for preparing an integrated positive electrode active material unit, an integrated negative electrode active material unit, or an integrated solid electrolyte includes the following steps:

[0041] Step 1: Fabricate positive electrode active material particles, negative electrode active material particles, or solid electrolyte particles into large-size materials at the millimeter level or above;

[0042] Step 2: Process the large-sized material into an integrated material unit.

[0043] In one embodiment of this application, the large-size cathode material includes a cathode active material, which includes at least one of lithium-ion battery cathode active materials, sodium-ion battery cathode active materials, and potassium-ion battery cathode active materials. The cathode active material can be any secondary battery cathode active material; for example, lithium-ion battery cathode active materials include LiCoO2 and LiNi. 0.8 Co 0.1 Mn 0.1 O2, Li[Ni 0.8 Co 0.15 Al 0.05 ]O2, LiFePO4, LiMn2O4, LiNi 0.5 Mn 1.5 O4, OLO, MoS2, MnO2, MoO3, CoFe2O4, Li x Co y Ni z Mn (1-y-z) O w Li x Fe y Ni z Mn (1-y-z) O w Li x Fe y Ni z Mn (1-y-z) PO w、 Li x / 2 Mn y Ni z O w At least one of the following, wherein 0.0 ≤ x < 0.8, 0.0 ≤ (z, y) ≤ 1.0, and 1.0 ≤ w ≤ 4.0; the positive electrode active material of sodium-ion batteries includes NaNi. 1 / 3 Fe 1 / 3 Mn 1 / 3 O2, NaFe 0.6 Ni 0.2 Mn 0.2 O2, Na2Fe2 (SO4)3, Na4Fe3(PO4)2(P2O7), Na 3.4 V 1.6 Mn 0.4 At least one of (PO4)3, NaFe[Fe(CN)6], Na2Fe[Fe(CN)6], Na2Mn[Mn(CN)6], and MoS2; the positive electrode active material for potassium-ion batteries includes KNi. 1 / 3 Fe 1 / 3 Mn 1 / 3 O2, KFe 0.6 Ni 0.2 Mn 0.2 O2, K2Fe2(SO4)3, K4Fe3(PO4)2(P2O7), K 3.4 V 1.6 Mn 0.4 At least one of (PO4)3, KFe[Fe(CN)6], K2Fe[Fe(CN)6], and K2Mn[Mn(CN)6].

[0044] In one embodiment of this application, the large-size negative electrode material includes a negative electrode active material; the negative electrode active material is at least one of a carbon negative electrode material or a non-carbon negative electrode material. The negative electrode active material includes all known negative electrode active materials for secondary batteries, excluding pure metals, such as carbon-based materials (natural graphite, artificial graphite, soft carbon, hard carbon, etc.), silicon-based materials (such as silicon, silicon suboxide, silicon-carbon, etc.), lithium-based materials (such as lithium-carbon, lithium-aluminum alloy, etc.), tin-based materials, titanium-based materials, nitride materials, phosphide materials, transition metal oxides (K2Ti2O5, VPO4, and V2O3, etc.), sulfides (MoS2, WS2, ReS2, and CoS, etc.), and selenides (MoSe2, Co...). 0.85 Se and MoSSe, etc.), carbonitrides (Ti3CNTz and Fe3C, etc.), K2Ti2O5, etc.), conversion reaction anodes (CuO, Ti6O, etc.). 11 At least one of Co3O4-F2O3 / C, SnS2, Sb2S3, FeS2, NiS, Cu2S, ZnS, CoS, FeSe2, ZnSe, and NiSe2.

[0045] In one embodiment of this application, the large-size solid electrolyte material includes at least one of oxide solid electrolyte materials, sulfide solid electrolyte materials, halide solid electrolyte materials, polymer solid electrolytes, borohydride solid electrolyte materials, and composite solid electrolyte materials. Specifically, the oxide solid electrolyte material includes garnet-based Li7La3Zr2O. 12 Perovskite-type Li 0.33 La0.557 TiO3 and LiSiCON structure Li 1.3 Al 0.3 Ti 1.7 (PO4)3; sulfide solid electrolyte materials include Li 10 GeP2S 12 Li2S-P2S5-LiCl; halide solid electrolyte materials include Li9N2Cl3; polymer solid electrolytes include PEO, polyacrylonitrile (PAN), polyvinyl alcohol (PVA), and polyvinylpyrrolidone (PVP); oxide-based solid electrolytes include Na-β-Al2O3 type solid electrolytes, NASICON type solid electrolyte materials, sulfide solid electrolyte materials (Na3PS4, K3PS4); borohydride solid electrolyte materials, and composite solid electrolyte materials.

[0046] In one embodiment of this application, the large-size material is made by at least one of in-situ growth, high-temperature sintering, and chemical synthesis.

[0047] In one embodiment of this application, the chemical size is at the atomic or molecular level. In conventional positive and negative electrode systems, most are particulate mixtures with particle sizes below 0.5 mm. Adhesives and conductive agents need to be added between the particles to ensure the integrity and conductivity of the positive electrode system. The integrated positive and negative electrode active material unit of this application is an integrated unit. The integrated unit has excellent conductivity due to the intercrystalline connections. The positive electrode active material unit does not require the addition of non-positive electrode active materials for conductive or bonding purposes, significantly improving the energy density of the positive electrode system; similarly, the negative electrode active material unit does not require the addition of non-positive electrode active materials for conductive or bonding purposes, significantly improving the energy density of the negative electrode system.

[0048] In one embodiment of this application, the integrated positive electrode includes a positive current collector and an integrated positive active material unit disposed on at least one surface of the positive current collector; the integrated negative electrode includes a negative current collector and an integrated negative active material unit disposed on at least one surface of the negative current collector. The integrated positive active material unit can be disposed on one surface or both surfaces of the positive current collector; the integrated negative active material unit can be disposed on one surface or both surfaces of the negative current collector. In conventional positive and negative electrode systems, most are particle mixtures with particle sizes below 0.5 mm. Adhesives and conductive agents need to be added between the particles to ensure the integrity and conductivity of the positive and negative electrode system. The integrated positive active material unit of this application is an integrated unit. The integrated unit has excellent conductivity, with internal crystal connections. The integrated unit does not require the addition of non-active materials for conductive or bonding purposes, significantly improving the energy density of the positive and negative electrode system.

[0049] In one embodiment of this application, at least one of the integrated positive electrode, integrated negative electrode, and integrated solid electrolyte is provided with a surface modification layer. The surface modification method includes physical coating; the integrated positive electrode active material unit or the integrated negative electrode active material unit can have an electrolyte layer coated on its surface, so that the surface-modified side of the integrated positive electrode can be directly connected to the integrated negative electrode without the need for a solid electrolyte and without short circuit. The surface modification layer increases the operability of the integrated positive and integrated negative electrode combination, providing more possible combination structures. Similarly, the integrated solid electrolyte can also have a surface modification layer coated on at least one surface. When the surface modification layer on one surface of the integrated solid electrolyte includes a negative electrode active material layer, the surface modification layer on the other surface includes a positive electrode active material or has no surface active layer, and vice versa. When the surface modification layer on one surface of the integrated solid electrolyte unit includes a negative electrode active material, a negative electrode is not required when assembling the battery; when the surface modification layer on one surface of the integrated solid electrolyte unit includes a positive electrode active material, a positive electrode is not required when assembling the battery. The surface modification layer increases the operability of the integrated solid electrolyte combination, providing more possible combination structures.

[0050] In one embodiment of this application, the surface modification layer of the integrated solid electrolyte includes a negative electrode active material or a positive electrode active material. When the surface modification layer of the integrated solid electrolyte includes a negative electrode active material, a negative electrode current collector can be directly connected; when the surface modification layer of the integrated solid electrolyte includes a positive electrode active material, a positive electrode current collector can be directly connected. The surface modification layer increases the operability of the integrated solid electrolyte assembly and provides more combinable structures.

[0051] In one embodiment of this application, the integrated positive electrode, the integrated negative electrode, and the integrated solid electrolyte are connected by bonding, pressurizing, heating, or sintering.

[0052] In one embodiment of this application, the processing method is cutting or molding.

[0053] In one embodiment of this application, the positive current collector is aluminum foil or composite aluminum foil, and the negative current collector is copper foil, aluminum foil, composite copper foil, or composite aluminum foil.

[0054] In one embodiment of this application, at least one integrated positive electrode active material unit is disposed on at least one surface of the positive electrode current collector; at least one integrated negative electrode active material unit is disposed on at least one surface of the negative electrode current collector. The integrated positive electrode active material units are closely arranged on the positive electrode current collector, providing an integrated positive electrode of suitable size, and no adhesive is required between the individual integrated positive electrode active material units. Similarly, the integrated negative electrode active material units are closely arranged on the positive electrode current collector, providing an integrated positive electrode of suitable size, and no adhesive is required between the individual integrated negative electrode active material units.

[0055] This application also provides an integrated solid-state battery, including at least one of the aforementioned integrated solid-state battery cells. In this application, the integrated solid-state battery may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, chloride-ion batteries, or magnesium-ion batteries, etc., and the embodiments of this application are not limited thereto. The battery cell may be cylindrical, flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited thereto.

[0056] In one embodiment of this application, the integrated solid-state batteries are connected in series, in parallel, or in a series-parallel connection.

[0057] The present invention also provides an electrical device including the aforementioned secondary battery, wherein the electrical device may be a mobile phone, portable device, laptop computer, electric vehicle, electric car, ship, spacecraft, electric toy, and power tool, etc. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers.

[0058] Based on the disclosure and teachings of the foregoing specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments described above, and any obvious improvements, substitutions, or modifications made by those skilled in the art based on the present invention are within the scope of protection of the present invention. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on the present invention.

Claims

1. An integrated solid-state battery cell, characterized in that, Combinations consisting of at least two of the following: an integrated solid electrolyte, an integrated negative electrode, and an integrated positive electrode, stacked together. The integrated solid electrolyte is an integrated unit formed by processing large-size solid electrolyte materials of millimeter size and above, and its chemically continuous size in at least one direction in three-dimensional space is a, where a satisfies the relationship: a≥0.5mm; The integrated negative electrode active material unit is an integrated unit formed by processing large-size negative electrode materials of millimeter size and above, and its chemically continuous size in at least one direction in three-dimensional space is b, which satisfies the relationship: b≥0.5mm; The integrated positive electrode active material unit is an integrated unit formed by processing large-size positive electrode materials of millimeter size and above. Its chemically continuous size in at least one direction in three-dimensional space is c, and c satisfies the relationship: c≥0.5mm.

2. The integrated solid-state battery cell according to claim 1, characterized in that, The integrated positive electrode includes a positive current collector and an integrated positive active material unit disposed on at least one surface of the positive current collector; the integrated negative electrode includes a negative current collector and an integrated negative active material unit disposed on at least one surface of the negative current collector.

3. The integrated solid-state battery cell according to claim 1, characterized in that, At least one of the integrated positive electrode, integrated negative electrode and integrated solid electrolyte is provided with a surface modification layer.

4. The integrated solid-state battery cell according to claim 1, characterized in that, The integrated positive electrode, integrated negative electrode, and integrated solid electrolyte are connected by bonding, pressurization, heating, or sintering.

5. The integrated solid-state battery cell according to claim 3, characterized in that, The surface modification layer of the integrated solid electrolyte includes either a negative electrode active material or a positive electrode active material.

6. The integrated solid-state battery cell according to claim 1, characterized in that, The processing method is one of cutting and mold forming.

7. The integrated solid-state battery cell according to claim 1, characterized in that, The positive current collector includes one of aluminum foil and composite aluminum foil, and the negative current collector includes one of copper foil, aluminum foil, composite copper foil, and composite aluminum foil.

8. The integrated solid-state battery cell according to claim 1, characterized in that, At least one integrated positive electrode active material unit is disposed on at least one surface of the positive electrode current collector; at least one integrated negative electrode active material unit is disposed on at least one surface of the negative electrode current collector.

9. An integrated solid-state battery, characterized in that, It includes at least one integrated solid-state battery cell as described in any one of claims 1 to 8.

10. The integrated solid-state battery according to claim 9, characterized in that, The integrated solid-state batteries are connected in series, in parallel, or in a series-parallel configuration.

Images