All-solid-state cylindrical battery and preparation method and equipment thereof

Abstract

The embodiment of the invention provides an all-solid-state cylindrical battery and a preparation method and equipment thereof. The all-solid-state cylindrical battery comprises a cylindrical shell as well as a negative collector plate, a naked battery cell, a central column and a positive collector plate which are packaged in the cylindrical shell, wherein the naked battery core is obtained by compounding and winding a positive electrode composite pole roll and negative electrode pole rolls on the two sides; the positive electrode composite pole roll comprises an aluminum foil, a positive electrode material coated on two surfaces of the aluminum foil and an electrolyte membrane coated on the surface of the positive electrode material; the negative electrode roll comprises a copper foil and a negative electrode material coated on one surface of the copper foil; and a negative electrode main material in the negative electrode material is at least one of nano silicon, micron silicon and silicon carbon. According to the all-solid-state cylindrical battery, close contact of material particles in the all-solid-state cylindrical battery can be realized without applying high voltage by an external device, so that the effective transmission effect of lithium ions is ensured.

Description

Technical Field

[0001] The present invention relates to the field of solid-state batteries, and in particular to an all-solid-state cylindrical battery and a preparation method and equipment thereof. Background Art

[0002] Since all-solid-state batteries do not contain liquid electrolytes and only rely on solid-solid contact between solid particles to transfer lithium ions, in order to ensure the charge and discharge performance of solid-state batteries, it is necessary to continuously maintain high pressure during battery operation to ensure close contact between the internal battery cell materials to ensure effective transmission of lithium ions.

[0003] Currently, all-solid-state batteries are primarily soft-pack structures, and during the charge and discharge process, an external pressurizing device is required to apply a pressure of 5 MPa or more to the battery to ensure close contact between the battery cell material particles. However, if all-solid-state batteries are to be used in vehicles, the existing pressurizing methods pose significant challenges to the entire vehicle module. For example, the pressure applied by the external device can have a variety of adverse effects on the battery cells, battery management system, connecting components, and structural framework within the vehicle module.

[0004] Therefore, how to achieve close contact of battery material particles without using an external pressurizing device is a technical problem that needs to be solved urgently. Summary of the Invention

[0005] The present invention provides an all-solid-state cylindrical battery and a preparation method and equipment thereof, which are used to achieve close contact of its battery core material particles during the battery charging and discharging process without relying on external devices to apply high voltage to the battery, thereby ensuring the effective transmission of lithium ions and effectively overcoming the defects of the existing technology.

[0006] A first aspect of the present invention provides an all-solid-state cylindrical battery, comprising: a cylindrical shell, and a negative electrode current collector, a bare cell, a central column, and a positive electrode current collector encapsulated in the cylindrical shell;

[0007] The bare cell is obtained by combining the positive electrode composite coil with the negative electrode coils on both sides and winding them together;

[0008] The positive electrode composite coil includes an aluminum foil, a positive electrode material coated on both sides of the aluminum foil, and an electrolyte membrane coated on the surface of the positive electrode material;

[0009] The negative electrode coil includes a copper foil and a negative electrode material coated on one side of the copper foil, wherein the negative electrode main material in the negative electrode material is at least one of nano-silicon, micro-silicon and silicon carbon.

[0010] According to one embodiment of the present invention, the central column is arranged along the axis of the bare battery core, and the cylindrical shell is covered on the outside of the bare battery core;

[0011] Wherein, the ratio of the outer diameter of the bare battery core to the inner diameter of the cylindrical shell is greater than 99%, and / or the ratio of the outer diameter of the central column to the inner diameter of the bare battery core is greater than or equal to 95%.

[0012] According to one embodiment of the present invention, the positive electrode composite coil further includes a gasket coating coated on both side edges of the positive electrode material along the winding direction, the surface of the gasket coating is coated with an electrolyte membrane layer, and the gasket coating is an insulating material.

[0013] According to one embodiment of the present invention, the negative electrode coil further includes a gasket coating applied on the edge of the negative electrode tab of the negative electrode material, and the gasket coating is an insulating material.

[0014] According to one embodiment of the present invention, the raw material of the gasket coating is UV light curing resin.

[0015] According to one embodiment of the present invention, the UV light-curable resin is at least one of epoxy acrylate, polyurethane acrylate, polyester acrylate, amino acrylate, and photo-imaging alkali-soluble resin.

[0016] According to one embodiment of the present invention, the width of the gasket coating is 3-5 mm.

[0017] According to one embodiment of the present invention, the positive electrode tab and the negative electrode tab are located at both ends of the bare battery cell;

[0018] At the positive electrode tab end of the bare cell, the distance between the edge of the negative electrode coil and the edge of the gasket coating on the positive electrode tab side of the positive electrode composite coil is 1.0 to 2.0 mm;

[0019] At the negative electrode tab end of the bare battery cell, the distance between the edge of the gasket coating in the negative electrode coil and the edge of the positive electrode composite coil is 1.0 to 2.0 mm.

[0020] According to one embodiment of the present invention, the electrolyte membrane is composed of a solid electrolyte and a binder;

[0021] The solid electrolyte is Li (6-x) PS (5-x) M (1+x) or at least one of yLi2S·(1-y)P2S5, wherein 0≤x≤0.6, 0.2≤y≤0.8, M=Cl, Br, I; and / or,

[0022] The binder is at least one of nitrile rubber, hydrogenated nitrile rubber, styrene-butadiene rubber, isoprene rubber and butadiene rubber.

[0023] According to one embodiment of the present invention, the solid electrolyte accounts for 97% to 99.5% of the electrolyte membrane.

[0024] According to one embodiment of the present invention, the thickness of the aluminum foil is ≥10 μm; and / or the thickness of the copper foil is ≥4.5 μm.

[0025] According to one embodiment of the present invention, the negative electrode material is composed of a negative electrode main material, a conductive agent and a binder;

[0026] Wherein, the conductive agent is at least one of SP, ECP, CNT, and VGCF; and / or,

[0027] The binder is at least one of sodium carboxymethyl cellulose, styrene-butadiene rubber, polyacrylic acid, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, nitrile rubber, hydrogenated nitrile rubber, styrene-butadiene rubber, isoprene rubber, and butadiene rubber.

[0028] According to one embodiment of the present invention, the positive electrode material is composed of a positive electrode main material, a solid electrolyte, a conductive agent and a binder;

[0029] Wherein, the main material of the positive electrode is at least one of lithium nickel cobalt manganese oxide, lithium-rich material, and lithium iron phosphate; and / or,

[0030] The solid electrolyte is at least one of a sulfide electrolyte and a halide electrolyte; and / or,

[0031] The conductive adhesive is at least one of SP, ECP, CNT, and VGCF; and / or,

[0032] The binder is at least one of PVDF and PTFE.

[0033] A second aspect of the present invention provides a method for preparing an all-solid-state cylindrical battery, comprising:

[0034] Coating the positive electrode material on both sides of the aluminum foil and coating the electrolyte membrane on the surface of the positive electrode material to obtain a positive electrode composite coil;

[0035] A negative electrode material is coated on one side of the copper foil to obtain a negative electrode coil; the negative electrode main material in the negative electrode material is at least one of nano-silicon, micro-silicon, and silicon carbon;

[0036] The positive electrode composite coil is combined with the negative electrode coils on both sides and wound to obtain a bare battery cell;

[0037] The bare battery cell, the negative electrode current collecting plate, the central column, and the positive electrode current collecting plate are encapsulated in a cylindrical shell to obtain the all-solid-state cylindrical battery described in the first aspect and / or various embodiments of the first aspect.

[0038] According to one embodiment of the present invention, the positive electrode material is coated on both sides of the aluminum foil, and the electrolyte membrane is coated on the surface of the positive electrode material to obtain a positive electrode composite coil, comprising:

[0039] Coating positive electrode materials on both sides of the aluminum foil, coating gasket coatings on both side edges of the positive electrode materials along the winding direction, and coating electrolyte membranes on the surfaces of the positive electrode materials and the gasket coatings to obtain the positive electrode composite coil;

[0040] Wherein, the gasket coating is an insulating material.

[0041] According to one embodiment of the present invention, the process of coating a negative electrode material on one side of a copper foil to obtain a negative electrode coil comprises:

[0042] Coating a negative electrode material on one side of a copper foil, and coating a gasket coating on the edge of the negative electrode tab of the negative electrode material to obtain the negative electrode coil;

[0043] Wherein, the gasket coating is an insulating material.

[0044] According to one embodiment of the present invention, the process of combining the positive electrode composite coil with the negative electrode coils on both sides and winding them to obtain a bare battery cell includes:

[0045] Rolling and compounding the positive electrode composite coil and the negative electrode coils on both sides using rollers to obtain positive and negative electrode composite coils;

[0046] The positive and negative electrode composite coils are wound to obtain the bare battery cell.

[0047] A third aspect of the present invention provides a pole winding composite device, comprising: a positive pole composite pole winding unwinding device, two negative pole winding unwinding devices, two composite rollers, and a positive and negative pole composite pole winding winding device;

[0048] The positive electrode composite roll unwinding device is used to input the positive electrode composite roll between the two composite rollers;

[0049] The two negative electrode coil unwinding devices are respectively arranged on both sides of the positive electrode composite coil unwinding device, and each negative electrode coil unwinding device is used to input the negative electrode coil into between the two composite rollers;

[0050] The two composite rollers are used to receive the positive electrode composite roll and the negative electrode roll, and roll-compress the positive electrode composite roll and the negative electrode rolls on both sides to obtain positive and negative electrode composite rolls;

[0051] The positive and negative electrode composite coil winding device is used to wind up the positive and negative electrode composite coil.

[0052] According to one embodiment of the present invention, the pole winding composite equipment further comprises: a positive pole composite pole winding detection device, a negative pole winding detection device, and a positive and negative pole composite pole winding detection device;

[0053] The positive electrode composite coil detection device is used to detect the surface quality of the positive electrode composite coil and the edge alignment of the positive electrode composite coil;

[0054] The negative electrode coil detection device is used to detect the surface quality of the side of the negative electrode coil coated with the negative electrode material and the edge alignment of the negative electrode coil;

[0055] The positive and negative electrode composite coil detection device is used to detect the surface quality of the positive and negative electrode composite coil and the edge alignment of the positive and negative electrode composite coil.

[0056] In a fourth aspect, an embodiment of the present invention provides an electrical device, which includes a device body and an all-solid-state cylindrical battery as described in the first aspect and / or various embodiments of the first aspect.

[0057] The implementation of the present invention has at least the following beneficial effects:

[0058] In the all-solid-state cylindrical battery provided by the present invention, since a silicon-containing material with expansion properties is used as the main material of the battery's negative electrode, the prepared bare battery cell expands in volume after the first power-on. Since the bare battery cell is encapsulated in a hard cylindrical shell, the cylindrical shell exerts a huge binding force on the interior of the bare battery cell, thereby achieving close contact of the material particles inside the battery without relying on external devices to apply high voltage to the battery, thereby ensuring the effective transmission of lithium ions. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0060] Figure 1 A schematic diagram of the structure of the all-solid-state cylindrical battery provided in this embodiment before assembly;

[0061] Figure 2 A schematic structural diagram of the all-solid-state cylindrical battery provided in this embodiment;

[0062] Figure 3 This is a schematic diagram of the right side structure of the positive electrode composite coil provided in this embodiment;

[0063] Figure 4A schematic diagram of the top view of the positive electrode composite coil provided in this embodiment;

[0064] Figure 5 A schematic diagram of the right side structure of a negative electrode coil provided in an embodiment;

[0065] Figure 6 A schematic top view of the negative electrode coil provided in an embodiment;

[0066] Figure 7 A schematic diagram of the composite position of the positive electrode composite coil and the negative electrode coil provided in this embodiment;

[0067] Figure 8 A top view of the positive and negative electrode composite coil provided in this embodiment;

[0068] Figure 9 An embodiment of the present invention provides a pole winding composite device.

[0069] Explanation of the accompanying figures: 100-all-solid-state cylindrical battery; 10-cylindrical shell; 20-negative electrode current collecting plate; 30-bare cell; 31-positive electrode composite electrode roll; 311-aluminum foil; 3111-positive electrode tab; 312-positive electrode material; 313-gasket coating in positive electrode composite electrode roll; 314-electrolyte membrane; 32-negative electrode roll; 321-copper foil; 3211-negative electrode tab; 322-negative electrode material; 323-gasket coating in negative electrode roll; 40-center column; 50-positive electrode current collecting plate; 60-electrode roll composite equipment; 61-positive electrode composite electrode roll unwinding device; 62-two negative electrode roll unwinding devices; 63-composite roller; 64-positive and negative electrode composite electrode roll winding device; 65-positive electrode composite electrode roll detection device; 66-negative electrode roll detection device; 67-positive and negative electrode composite electrode roll detection device. DETAILED DESCRIPTION

[0070] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below. The specific embodiments listed below are only for describing the principles and features of the present invention. The examples are only used to explain the present invention and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts are within the scope of protection of the present invention.

[0071] Based on the above background technology, an embodiment of the present invention provides an all-solid-state cylindrical battery. Figure 1 This is a schematic diagram of the structure of the all-solid-state cylindrical battery before assembly provided in this embodiment, as shown in FIG. Figure 1 As shown, the all-solid-state cylindrical battery 100 provided in an embodiment of the present invention includes: a cylindrical shell 10 and a negative electrode current collecting disk 20, a bare battery cell 30, a central column 40 and a positive electrode current collecting disk 50 encapsulated in the cylindrical shell 10.

[0072] Among them, the bare battery cell 30 is obtained by combining and winding the positive electrode composite coil with the negative electrode coils on both sides; the positive electrode composite coil includes aluminum foil, positive electrode material coated on both sides of the aluminum foil, and an electrolyte membrane coated on the surface of the positive electrode material; the negative electrode coil includes copper foil and negative electrode material coated on one side of the copper foil, and the negative electrode main material in the negative electrode material is at least one of nano-silicon, micron silicon and silicon carbon.

[0073] Figure 2 This is a schematic diagram of the structure of the all-solid-state cylindrical battery provided in this embodiment. After assembling the cylindrical shell 10, the negative electrode current collecting plate 20, the bare battery cell 30, the central column 40 and the positive electrode current collecting plate 50, the battery is obtained. Figure 2 The all-solid-state cylindrical battery 100 is shown.

[0074] According to Ming people's research, if at least one of the silicon-containing materials such as nano-silicon, micro-silicon and silicon-carbon is used as the main material of the negative electrode of the battery, the volume of the silicon material in the battery will expand due to changes in the silicon crystal structure caused by the insertion and extraction of lithium ions during the charging and discharging process. Therefore, the inventors considered preparing the bare battery cell with the above-mentioned silicon-containing material as the main material of the negative electrode into a cylindrical structure, and encapsulating the bare battery cell in a hard cylindrical shell, so that during the charging and discharging process, after the volume of the bare battery cell expands, the cylindrical shell can generate a huge binding force on the inside of the bare battery cell, thereby achieving the effect of achieving close contact of the material particles inside the battery without relying on external devices to apply high voltage to the battery, thereby ensuring the effective transmission of lithium ions.

[0075] According to one embodiment of the present invention, the central column is arranged along the axis of the bare battery core, and the cylindrical shell is covered on the outside of the bare battery core.

[0076] The ratio of the outer diameter of the bare cell to the inner diameter of the cylindrical shell in the all-solid-state cylindrical battery is greater than 99%. It should be understood that the ratio of the outer diameter of the bare cell to the inner diameter of the cylindrical shell is to ensure that the bare cell can enter the shell. On the basis that the bare cell can enter the shell, in order to make the cylindrical shell have a greater binding force on the bare cell after the silicon material expands, it is necessary to set the ratio of the outer diameter of the bare cell to the inner diameter of the cylindrical shell as large as possible. Specifically, the ratio of the outer diameter of the bare cell to the inner diameter of the cylindrical shell can be 99.1%, 99.2%, 99.3%, 99.4%, 99.5%, 99.6%, 99.7%, 99.8%, 99.9%, or other values greater than 99%, and is not limited to the listed values. Other values not listed within the given range are also applicable.

[0077] In addition, the center column plays a supporting role inside the battery, and a higher proportion can help enhance the overall mechanical strength of the battery.

[0078] Based on this, the ratio of the outer diameter of the central column in the all-solid-state cylindrical battery to the inner diameter of the bare cell can be set to ≥ 95%. Specifically, the ratio of the outer diameter of the central column to the inner diameter of the bare cell is, for example, 95%, 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5%, 99%, etc., which is ≥ 95% and can ensure that the central column is arranged along the axis of the bare cell. It should be noted that the values are not limited to the listed values, and other values not listed within the given range are also applicable.

[0079] According to the inventors' further research, it was found that when designing the structure of a battery, it is often necessary to set the area of the active material in the negative electrode to be larger than the area of the active material in the positive electrode. This makes the size of the designed positive electrode sheet generally smaller than that of the negative electrode sheet. As a result, during the composite process of the positive and negative electrodes, the edge of the positive electrode sheet will generate a huge shear force on the negative electrode sheet, which can easily cause the negative electrode sheet to rupture and short-circuit with the positive electrode sheet. Based on this, the inventors found that by providing a gasket coating made of insulating material in the positive electrode composite coil and / or the negative electrode coil in the all-solid-state cylindrical battery, this problem can be effectively solved. In addition, it can also effectively prevent the risk of short circuit caused by burrs on the edges of the aluminum foil or copper foil.

[0080] Accordingly, according to one embodiment of the present invention, Figure 3 This is a schematic diagram of the right side structure of the positive electrode composite coil provided in this embodiment. Figure 4 This is a schematic diagram of the top view of the positive electrode composite coil provided in this embodiment (the electrolyte membrane is not shown), as shown in FIG. Figure 3 and Figure 4 As shown, the positive electrode composite coil 31 includes an aluminum foil 311, a positive electrode material 312 coated on both sides of the aluminum foil 311, a gasket coating 313 coated on both sides of the positive electrode material 312 along the winding direction, and an electrolyte membrane 314 coated on the surfaces of the positive electrode material 312 and the gasket coating 313. The gasket coating 313 is an insulating material; the portion of the aluminum foil 311 not coated with the positive electrode material 312 and the gasket coating 313 is the positive electrode tab 3111.

[0081] In addition, according to one embodiment of the present invention, Figure 5 This is a schematic diagram of the right side structure of the negative electrode coil provided in the embodiment. Figure 6 A schematic diagram of the top view of the negative electrode coil provided in the embodiment is shown in FIG. Figure 5 and Figure 6 As shown, the negative electrode coil 32 includes a copper foil 321, a negative electrode material 322 coated on one side of the copper foil 321, and a gasket coating 323 coated on the side edge of the negative electrode tab 3211 of the negative electrode material 322, wherein the negative electrode main material in the negative electrode material 322 is at least one of nano-silicon, micron-silicon and silicon carbon.

[0082] Furthermore, according to one embodiment of the present invention, the gasket coating is made of ultraviolet-curable resin (UV). It should be understood that UV-curable resin is a resin material that rapidly cures from a liquid to a solid state under ultraviolet light and exhibits excellent insulating properties.

[0083] According to one embodiment of the present invention, the UV light-curable resin may be at least one of epoxy acrylate, polyurethane acrylate, polyester acrylate, amino acrylate, and photoimageable alkali-soluble resin. Specifically, the UV light-curable resin may be any one of epoxy acrylate, polyurethane acrylate, polyester acrylate, amino acrylate, and photoimageable alkali-soluble resin, or may be a combination of any number of these substances, for example, a combination of two, three, or more substances. This embodiment of the present invention does not impose any specific limitation on this.

[0084] According to one embodiment of the present invention, the width of the gasket coating is 3-5 mm.

[0085] Specifically, the width of the gasket coating in the positive electrode composite coil or the negative electrode coil can be 3-5 mm. For example, the width of the gasket coating is 3 mm, 3.2 mm, 3.4 mm, 3.8 mm, 4 mm, 4.2 mm, 4.4 mm, 4.6 mm, 4.8 mm, or 5 mm, or a value within a range formed by selecting any two of the aforementioned values.

[0086] According to one embodiment of the present invention, the positive and negative electrode tabs are located at both ends of the bare cell. At the positive tab end of the bare cell, the distance between the edge of the negative electrode coil and the edge of the gasket coating on the positive tab side of the positive electrode composite coil is 1.0 to 2.0 mm. At the negative tab end of the bare cell, the distance between the edge of the gasket coating in the negative electrode coil and the edge of the positive electrode composite coil is 1.0 to 2.0 mm.

[0087] Preferably, at the positive electrode tab end of the bare battery cell, the distance between the edge of the negative electrode coil and the edge of the gasket coating on the positive electrode tab side of the positive electrode composite coil is 1.5 mm; at the negative electrode tab end of the bare battery cell, the distance between the edge of the gasket coating in the negative electrode coil and the edge of the positive electrode composite coil is 1.5 mm.

[0088] It should be understood that since in some embodiments, the edge of one side of the negative electrode material in the negative electrode coil is coated with a gasket coating, in order to ensure the design requirement of "negative electrode wrapped around positive electrode" in the battery field, the negative electrode coil and the positive electrode composite coil can be staggered.

[0089] For example, Figure 7A schematic diagram of the composite position of the positive electrode composite coil and the negative electrode coil provided in this embodiment, as shown in FIG. Figure 7 As shown, on the positive electrode tab 3111 side of the positive electrode composite electrode roll 31 (corresponding to the positive electrode tab end of the bare battery cell), the distance between the edge of the negative electrode coil 32 and the edge of the gasket coating 313 on the positive electrode tab 3111 side of the positive electrode composite electrode roll 31 is 1.5 mm; on the negative electrode tab 3211 side of the negative electrode coil 32 (corresponding to the negative electrode tab end of the bare battery cell), the distance between the edge of the gasket coating 323 in the negative electrode coil 32 and the edge of the positive electrode composite electrode roll 31 is 1.5 mm. Figure 8 The top view of the positive and negative electrode composite coils provided in this embodiment (the electrolyte membrane is not drawn), accordingly, the positive electrode composite coil 31 and the negative electrode coil 32 are based on Figure 7 The composite position shown is composited to obtain the positive and negative composite pole coil 33 as shown in FIG. Figure 8 As shown, the positive and negative electrode composite coils are then wound to obtain a bare battery cell, which meets the design requirement of "negative electrode wrapped around positive electrode".

[0090] Furthermore, according to one embodiment of the present invention, the electrolyte membrane is composed of a solid electrolyte and a binder. The solid electrolyte is Li (6-x) PS (5-x) M (1+x) Or at least one of yLi2S·(1-y)P2S5, wherein 0≤x≤0.6, 0.2≤y≤0.8, M=Cl, Br, I.

[0091] According to an implementation of the present invention, the binder in the electrolyte membrane is at least one of nitrile rubber, hydrogenated nitrile rubber, styrene-butadiene rubber, isoprene rubber, and butadiene rubber.

[0092] According to one implementation of the present invention, the proportion of solid electrolyte in the electrolyte membrane is 97% to 99.5%. For example, the proportion of solid electrolyte in the electrolyte membrane is 97%, 97.25%, 97.5%, 97.75%, 98%, 98.25%, 98.5%, 98.75%, 99%, 99.25%, 99.5%, or a value within a new range formed by selecting any two of the foregoing values.

[0093] Furthermore, according to one embodiment of the present invention, the thickness of the aluminum foil in the positive electrode composite coil is ≥10 μm. Exemplary thicknesses include 10 μm, 10.5 μm, 11 μm, 13 μm, 15 μm, 18 μm, 20 μm, 23 μm, 25 μm, and other values greater than or equal to 10 μm. It should be noted that these values are not limited to the listed values, and other values within the given ranges are also applicable.

[0094] According to one embodiment of the present invention, the thickness of the copper foil in the negative electrode coil is ≥ 4.5 μm. Exemplary thicknesses include 4.5 μm, 5 μm, 7 μm, 9 μm, 11 μm, 13 μm, 15 μm, 17 μm, 19 μm, and other values greater than or equal to 4.5 μm. Note that these values are not limited to the listed values, and other values within the ranges not listed are also applicable.

[0095] It should be understood that the thickness of the aluminum foil in the positive electrode composite coil and the copper foil in the negative electrode coil is set to meet the mechanical and electrical conductivity requirements of the all-solid-state battery provided by the present invention. Setting the thickness of the aluminum foil in the positive electrode composite coil to ≥10μm and / or the thickness of the copper foil in the negative electrode coil to ≥4.5μm not only ensures good structural stability of the positive electrode composite coil and / or the negative electrode coil during the winding process and when the silicon material expands after charging and discharging, but also ensures that the positive electrode composite coil and / or the negative electrode coil have excellent electrical conductivity.

[0096] Furthermore, according to one embodiment of the present invention, the negative electrode material comprises a negative electrode main material, a conductive agent, and a binder. The conductive agent is at least one of SP, ECP, CNT, and VGCF; and / or the binder is at least one of sodium carboxymethyl cellulose, styrene-butadiene rubber, polyacrylic acid, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, nitrile rubber, hydrogenated nitrile rubber, styrene-butadiene rubber, isoprene rubber, and butadiene rubber.

[0097] Specifically, the conductive agent is any one of SP, ECP, CNT, and VGCF, and can also be composed of any combination of any multiple of the above substances, for example, it can be composed of two, three or more substances, and this embodiment of the present invention does not specifically limit this; and / or, the binder is any one of sodium carboxymethyl cellulose, styrene-butadiene rubber, polyacrylic acid, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, nitrile rubber, hydrogenated nitrile rubber, styrene-butadiene rubber, isoprene rubber, and butadiene rubber, and can also be composed of any combination of any multiple of the above substances, for example, it can be composed of two, three or more substances, and this embodiment of the present invention does not specifically limit this. Such an arrangement can effectively improve the versatility of the negative electrode material, so that the negative electrode material can meet various application scenarios.

[0098] Furthermore, according to one embodiment of the present invention, the positive electrode material comprises a main positive electrode material, a solid electrolyte, a conductive agent, and a binder. The main positive electrode material is at least one of lithium nickel cobalt manganese oxide, a lithium-rich material, and lithium iron phosphate; and / or the solid electrolyte is at least one of a sulfide electrolyte and a halide electrolyte; and / or the conductive binder is at least one of SP, ECP, CNT, and VGCF; and / or the binder is at least one of PVDF and PTFE.

[0099] Specifically, the main material of the positive electrode in the positive electrode material is any one of lithium nickel cobalt manganese oxide, lithium-rich material, and lithium iron phosphate, or it can be composed of any combination of multiple substances among the above substances, for example, it can be composed of two, three or more substances, and this embodiment of the present invention does not specifically limit this; and / or, the solid electrolyte is any one of a sulfide electrolyte and a halide electrolyte, or it can be composed of any combination of multiple substances among the above substances, for example, it can be composed of two, three or more substances, and this embodiment of the present invention does not specifically limit this; and / or, the conductive adhesive is any one of SP, ECP, CNT, and VGCF, or it can be composed of any combination of multiple substances among the above substances, for example, it can be composed of two, three or more substances, and this embodiment of the present invention does not specifically limit this; and / or, the binder is any one of PVDF and PTFE, or it can be composed of any combination of multiple substances among the above substances, for example, it can be composed of two, three or more substances, and this embodiment of the present invention does not specifically limit this. Such a setting can effectively improve the versatility of the positive electrode material, so that the positive electrode material can meet various application scenarios.

[0100] An embodiment of the present invention provides a method for preparing an all-solid-state cylindrical battery, comprising:

[0101] S101. Coating a positive electrode material on both sides of the aluminum foil, and coating an electrolyte membrane on the surface of the positive electrode material to obtain a positive electrode composite coil.

[0102] In this step, it is necessary to coat the positive electrode material on both sides of the aluminum foil, and coat the positive electrode material on each side with an electrolyte membrane, thereby obtaining a positive electrode composite coil.

[0103] According to one embodiment of the present invention, in order to avoid short circuit caused by contact between the positive electrode composite coil and the negative electrode coil in the battery, the positive electrode material is coated on both sides of the aluminum foil, and the electrolyte membrane is coated on the surface of the positive electrode material to obtain the positive electrode composite coil. Specifically, the process includes: coating the positive electrode material on both sides of the aluminum foil, coating the gasket coating on the edges of both sides of the positive electrode material along the winding direction, and coating the electrolyte membrane on the surface of the positive electrode material and the gasket coating to obtain the positive electrode composite coil; wherein the gasket coating is an insulating material.

[0104] S102. Coating a negative electrode material on one side of the copper foil to obtain a negative electrode coil; wherein the negative electrode main material in the negative electrode material is at least one of nano-silicon, micro-silicon, and silicon carbon.

[0105] In this step, it is sufficient to coat the negative electrode material on one side of the copper foil, wherein the negative electrode main material in the negative electrode material is at least one of nano-silicon, micro-silicon, and silicon carbon.

[0106] According to one embodiment of the present invention, in order to avoid short circuit caused by contact between the positive electrode composite coil and the negative electrode coil in the battery, a negative electrode material can also be coated on one side of the copper foil to obtain a negative electrode coil, specifically comprising: coating the negative electrode material on one side of the copper foil, and coating a gasket coating on the negative electrode ear side edge of the negative electrode material to obtain a negative electrode coil; wherein the gasket coating is an insulating material.

[0107] S103, combining the positive electrode composite coil with the negative electrode coils on both sides and winding them to obtain a bare battery cell.

[0108] In this step, it is necessary to set negative electrode coils on both sides of the positive electrode composite coil, and then combine the positive electrode composite coil with the negative electrode coils on both sides and wind them to obtain a bare battery cell.

[0109] According to one embodiment of the present invention, a bare cell can be obtained in the following manner:

[0110] Step 1: Use rollers to roll the positive electrode composite coil and the negative electrode coils on both sides to obtain positive and negative electrode composite coils.

[0111] It should be understood that when rollers are used to roll-combine the positive electrode composite coil with the negative electrode coils on both sides, there is line contact between the rollers and the negative electrode coils, and the contact area is small, which makes the local pressure during the composite larger. Therefore, there is no need to use the isostatic pressing composite method in the traditional scheme to achieve effective composite between the positive electrode composite coil and the negative electrode coils on both sides. In addition, the roller-combine composite method can achieve continuous production. The material is continuously advanced under the drive of the rollers, and the composite process is carried out continuously, which can effectively improve the production efficiency of the battery.

[0112] Step 2: Wind the positive and negative electrode composite coils to obtain a bare battery cell.

[0113] In this step, the positive and negative electrode composite coils are wound according to the preset inner diameter and radius of the bare cell to obtain a bare cell.

[0114] According to one embodiment of the present invention, the preset inner diameter and radius of the bare cell can be determined according to the rule that "the ratio of the outer diameter of the bare cell to the inner diameter of the cylindrical shell is greater than 99%, and / or the ratio of the outer diameter of the center column to the inner diameter of the bare cell is greater than or equal to 95%".

[0115] S104, encapsulating the bare battery cell, the negative electrode current collecting plate, the central column, and the positive electrode current collecting plate in a cylindrical shell to obtain the all-solid-state cylindrical battery provided by the present invention.

[0116] In this step, the bare cell, the negative electrode current collecting plate, the central column, and the positive electrode current collecting plate need to be assembled and encapsulated in a cylindrical shell to obtain the all-solid-state cylindrical battery provided by the present invention.

[0117] Among them, the central column is arranged along the axis of the bare battery cell; the cylindrical shell is covered on the outside of the bare battery cell; the negative electrode collector is connected to the negative electrode tab of the bare battery cell and is arranged at one end of the cylindrical shell; the positive electrode collector is connected to the positive electrode tab of the bare battery cell and is arranged at the other end of the cylindrical shell.

[0118] According to one implementation of the present invention, the bare cell, the negative electrode current collecting plate, the central column, and the positive electrode current collecting plate can be assembled by laser welding to obtain the all-solid-state cylindrical battery provided by the present invention.

[0119] Figure 9 The present invention provides a pole winding composite device, the pole winding composite device 60 is used to prepare the positive and negative electrode composite pole winding 33. Figure 9 As shown, the electrode winding composite device 60 provided in this embodiment includes: a positive electrode composite electrode winding unwinding device 61, two negative electrode winding unwinding devices 62, two composite rollers 63 and a positive and negative electrode composite electrode winding device 64;

[0120] The positive electrode composite roll unwinding device 61 is used to input the positive electrode composite roll 31 between the two composite rollers 63;

[0121] Two negative electrode coil unwinding devices 62 are respectively provided on both sides of the positive electrode composite coil unwinding device 61 , and each negative electrode coil unwinding device 62 is used to input the negative electrode coil 32 between the two composite rollers 63 ;

[0122] The two composite rollers 63 are used to receive the positive electrode composite roll 31 and the negative electrode roll 32, and roll-compress the positive electrode composite roll 31 and the negative electrode rolls 32 on both sides to obtain the positive and negative electrode composite rolls 33;

[0123] The positive and negative electrode composite electrode roll winding device 64 is used to roll up the positive and negative electrode composite electrode roll 33 .

[0124] According to one embodiment of the present invention, please continue to refer to Figure 9 The pole winding composite device 60 provided in this embodiment further includes:

[0125] Positive electrode composite coil detection device 65, negative electrode coil detection device 66 and positive and negative electrode composite coil detection device 67;

[0126] The positive electrode composite coil detection device 65 is used to detect the surface quality of the positive electrode composite coil 31 and the edge alignment of the positive electrode composite coil 31;

[0127] The negative electrode coil detection device 66 is used to detect the surface quality of the side of the negative electrode coil 32 coated with the negative electrode material and the edge alignment of the negative electrode coil 31;

[0128] The positive and negative electrode composite coil detection device 67 is used to detect the surface quality of the positive and negative electrode composite coil 33 and the edge alignment of the positive and negative electrode composite coil 33.

[0129] It should be understood that in order to ensure the consistency of the front and rear material lines during the unwinding and winding processes in the pole winding assembly equipment, and to prevent the material lines from deviating before the positive and negative electrode composite pole windings are wound, causing problems such as tearing, flying tape, and the correction mechanism being blocked due to excessive displacement; at the same time, to prevent the occurrence of positive and negative electrode short circuits, it is also necessary to detect the alignment between the positive electrode composite pole winding and the negative electrode pole winding. Based on this, a detection device for detecting the edge alignment of each pole winding can be provided in the pole winding assembly equipment, so that the position of the pole winding can be adjusted in a timely manner if the material line of the pole winding deviates.

[0130] In addition, in order to ensure the quality of the positive and negative electrode composite coils obtained by winding, improve the production yield of the positive and negative electrode composite coils, and thus improve the production efficiency of all-solid-state batteries, the above-mentioned detection device set in the coil composite equipment can also be used to detect the surface quality of each coil, so that when there are minor damages (such as burrs, gaps) and dust accumulation on the surface of the coil, the coil can be adjusted in time.

[0131] In the specific implementation of this solution, the positive electrode composite pole coil detection device, the negative electrode pole coil detection device, and the positive and negative electrode composite pole coil detection device can all be correction sensors. The correction sensor emits a light beam through laser or photoelectric technology, receives the light signal reflected by each pole coil, converts the light signal into an electrical signal, and then uses the electrical signal to calculate the surface quality and edge alignment of the pole coil. Specifically, the correction sensor is, for example, a laser correction sensor, a mirror reflection sensor, a through-beam sensor, a photoelectric sensor, etc. This application does not impose specific restrictions on the selection of the positive electrode composite pole coil detection device, the negative electrode pole coil detection device, and the positive and negative electrode composite pole coil detection device.

[0132] This embodiment provides a positive electrode composite electrode roll detection device, a negative electrode electrode roll detection device, and a positive and negative electrode composite electrode roll detection device in the electrode roll composite equipment, so that in the process of preparing and obtaining the positive and negative electrode composite electrode rolls, the edge alignment and surface quality of each electrode roll can be detected in real time, so as to achieve the technical effects of reducing the generation of waste and improving the production efficiency of all-solid-state batteries.

[0133] The electrode winding assembly equipment provided in this embodiment can be used to prepare positive and negative electrode composite electrode coils by roller rolling. By winding the positive and negative electrode composite electrode coils, a bare cell for preparing the all-solid-state cylindrical battery provided by the present invention can be obtained.

Claims

1. An all-solid-state cylindrical battery, characterized in that: include: A cylindrical shell and a negative electrode current collecting disc, a bare battery cell, a central column and a positive electrode current collecting disc encapsulated in the cylindrical shell; The bare cell is obtained by combining the positive electrode composite coil with the negative electrode coils on both sides and winding them together; The positive electrode composite coil includes an aluminum foil, a positive electrode material coated on both sides of the aluminum foil, and an electrolyte membrane coated on the surface of the positive electrode material; The negative electrode coil includes a copper foil and a negative electrode material coated on one side of the copper foil, wherein the negative electrode main material in the negative electrode material is at least one of nano-silicon, micro-silicon and silicon carbon.

2. The all-solid-state cylindrical battery according to claim 1, characterized in that: The central column is arranged along the axis of the bare battery core, and the cylindrical shell is covered on the outside of the bare battery core; Wherein, the ratio of the outer diameter of the bare battery core to the inner diameter of the cylindrical shell is greater than 99%, and / or the ratio of the outer diameter of the central column to the inner diameter of the bare battery core is greater than or equal to 95%.

3. The all-solid-state cylindrical battery according to claim 1, characterized in that: The positive electrode composite coil further includes a gasket coating coated on both side edges of the positive electrode material along the winding direction, the surface of the gasket coating is coated with an electrolyte membrane layer, and the gasket coating is an insulating material.

4. The all-solid-state cylindrical battery according to claim 1, characterized in that: The negative electrode coil further includes a gasket coating coated on the negative electrode tab side edge of the negative electrode material, and the gasket coating is an insulating material.

5. The all-solid-state cylindrical battery according to claim 3 or 4, characterized in that: The raw material of the gasket coating is UV light curing resin.

6. The all-solid-state cylindrical battery according to claim 5, characterized in that: The UV light-curable resin is at least one of epoxy acrylate, polyurethane acrylate, polyester acrylate, amino acrylate, and photo-imaging alkali-soluble resin.

7. The all-solid-state cylindrical battery according to claim 3 or 4, characterized in that: The width of the gasket coating is 3-5 mm.

8. The all-solid-state cylindrical battery according to claim 1, characterized in that: The positive electrode tab and the negative electrode tab are located at both ends of the bare battery cell; At the positive electrode tab end of the bare cell, the distance between the edge of the negative electrode coil and the edge of the gasket coating on the positive electrode tab side of the positive electrode composite coil is 1.0 to 2.0 mm; At the negative electrode tab end of the bare battery cell, the distance between the edge of the gasket coating in the negative electrode coil and the edge of the positive electrode composite coil is 1.0 to 2.0 mm.

9. The all-solid-state cylindrical battery according to claims 1 to 4, characterized in that: The electrolyte membrane is composed of a solid electrolyte and a binder; The solid electrolyte is Li (6-x) PS (5-x) M (1+x) or at least one of yLi2S·(1-y)P2S5, wherein 0≤x≤0.6, 0.2≤y≤0.8, M=Cl, Br, I; and / or, The binder is at least one of nitrile rubber, hydrogenated nitrile rubber, styrene-butadiene rubber, isoprene rubber and butadiene rubber.

10. The all-solid-state cylindrical battery according to claim 8, characterized in that: The solid electrolyte accounts for 97% to 99.5% of the electrolyte membrane.

11. The all-solid-state cylindrical battery according to any one of claims 1 to 4, characterized in that: The thickness of the aluminum foil is ≥10 μm; and / or the thickness of the copper foil is ≥4.5 μm.

12. The all-solid-state cylindrical battery according to any one of claims 1 to 4, characterized in that: The negative electrode material is composed of a negative electrode main material, a conductive agent and a binder; Wherein, the conductive agent is at least one of SP, ECP, CNT, and VGCF; and / or, The binder is at least one of sodium carboxymethyl cellulose, styrene-butadiene rubber, polyacrylic acid, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, nitrile rubber, hydrogenated nitrile rubber, styrene-butadiene rubber, isoprene rubber, and butadiene rubber.

13. The all-solid-state cylindrical battery according to any one of claims 1 to 4, characterized in that: The positive electrode material is composed of a positive electrode main material, a solid electrolyte, a conductive agent and a binder; Wherein, the main material of the positive electrode is at least one of lithium nickel cobalt manganese oxide, lithium-rich material, and lithium iron phosphate; and / or, The solid electrolyte is at least one of a sulfide electrolyte and a halide electrolyte; and / or, The conductive adhesive is at least one of SP, ECP, CNT, and VGCF; and / or, The binder is at least one of PVDF and PTFE.

14. A method for preparing an all-solid-state cylindrical battery, characterized in that: include: Coating the positive electrode material on both sides of the aluminum foil and coating the electrolyte membrane on the surface of the positive electrode material to obtain a positive electrode composite coil; A negative electrode material is coated on one side of the copper foil to obtain a negative electrode coil; the negative electrode main material in the negative electrode material is at least one of nano-silicon, micro-silicon, and silicon carbon; The positive electrode composite coil is combined with the negative electrode coils on both sides and wound to obtain a bare battery cell; The bare battery cell, the negative electrode current collecting plate, the central column, and the positive electrode current collecting plate are encapsulated in a cylindrical shell to obtain the all-solid-state cylindrical battery according to any one of claims 1 to 13.

15. The preparation method according to claim 14, characterized in that The positive electrode material is coated on both sides of the aluminum foil, and the electrolyte membrane is coated on the surface of the positive electrode material to obtain a positive electrode composite coil, including: Coating positive electrode materials on both sides of the aluminum foil, coating gasket coatings on both side edges of the positive electrode materials along the winding direction, and coating electrolyte membranes on the surfaces of the positive electrode materials and the gasket coatings to obtain the positive electrode composite coil; Wherein, the gasket coating is an insulating material.

16. The preparation method according to claim 14, characterized in that The negative electrode material is coated on one side of the copper foil to obtain a negative electrode coil, comprising: Coating a negative electrode material on one side of a copper foil, and coating a gasket coating on the edge of the negative electrode tab of the negative electrode material to obtain the negative electrode coil; Wherein, the gasket coating is an insulating material.

17. The preparation method according to any one of claims 14 to 16, characterized in that: The positive electrode composite coil is combined with the negative electrode coils on both sides and wound to obtain a bare battery cell, comprising: Rolling and compounding the positive electrode composite coil and the negative electrode coils on both sides using rollers to obtain positive and negative electrode composite coils; The positive and negative electrode composite coils are wound to obtain the bare battery cell.

18. A pole winding composite device, characterized in that: The electrode winding composite equipment includes: a positive electrode composite electrode winding unwinding device, two negative electrode winding unwinding devices, two composite rollers and a positive and negative electrode composite electrode winding device; The positive electrode composite roll unwinding device is used to input the positive electrode composite roll between the two composite rollers; The two negative electrode coil unwinding devices are respectively arranged on both sides of the positive electrode composite coil unwinding device, and each negative electrode coil unwinding device is used to input the negative electrode coil into between the two composite rollers; The two composite rollers are used to receive the positive electrode composite roll and the negative electrode roll, and roll-compress the positive electrode composite roll and the negative electrode rolls on both sides to obtain positive and negative electrode composite rolls; The positive and negative electrode composite coil winding device is used to wind up the positive and negative electrode composite coil.

19. The pole winding composite equipment according to claim 18, characterized in that: The pole coil composite equipment also includes: a positive pole composite pole coil detection device, a negative pole coil detection device and a positive and negative pole composite pole coil detection device; The positive electrode composite coil detection device is used to detect the surface quality of the positive electrode composite coil and the edge alignment of the positive electrode composite coil; The negative electrode coil detection device is used to detect the surface quality of the side of the negative electrode coil coated with the negative electrode material and the edge alignment of the negative electrode coil; The positive and negative electrode composite coil detection device is used to detect the surface quality of the positive and negative electrode composite coil and the edge alignment of the positive and negative electrode composite coil.

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