Solid-state cylindrical battery and preparation method and application thereof

Abstract

The invention relates to the field of batteries, in particular to a solid-state cylindrical battery and a preparation method and application thereof. The solid-state cylindrical battery comprises a battery cell and an insulating shell arranged outside the battery cell, the battery cell comprises a first composite current collector, a negative electrode material layer, a solid electrolyte diaphragm, an electrode lamination body, a solid electrolyte diaphragm, a positive electrode material layer and a second composite current collector which are laminated in sequence; the electrode laminated body comprises a plurality of laminated positive and negative pole piece composites, and a solid electrolyte diaphragm is arranged between every two adjacent positive and negative pole piece composites. The solid-state cylindrical battery is simple in structure, short in manufacturing period and low in preparation cost, and has relatively high energy density and voltage.

Description

Technical Field

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

[0002] As lithium-ion batteries are used in all areas of production and life, people have put forward higher requirements for their energy density, cost and safety performance. All-solid-state batteries have become the focus of research due to their inherent safety and high energy density. However, the main packaging form currently used by all-solid-state batteries is the soft-pack form. The battery module is finally prepared into a battery system by complex external series-parallel connection of single soft-pack cells. Because the voltage of a single cell is low and the energy of a single cell is small, the complex external series-parallel connection will reduce the grouping efficiency of the battery system and thus reduce the overall energy density of the battery system. In addition, the existing commercial power battery cells use metal shells as the main packaging form, so after the cell is prepared, external insulation treatment is required, including but not limited to the pasting of insulating film on the outside of the cell, the pasting of insulating top patches on the top of the cell, the coating of insulating coatings on the battery box in the battery system or the pasting of other insulating materials, etc. The introduction of these complex insulating materials will not only increase the production cycle of the entire process of the battery system, but also increase the cost of battery system products to a certain extent, hindering the further development of the lithium-ion battery industry.

[0003] In view of this, the present invention is proposed. Summary of the invention

[0004] The object of the present invention is to provide a solid-state cylindrical battery and a preparation method and application thereof. The solid-state cylindrical battery has the advantages of simple structure, short production cycle, low preparation cost, high energy density, etc.

[0005] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0006] One aspect of the present invention relates to a solid-state cylindrical battery, comprising a battery cell and an insulating shell disposed outside the battery cell;

[0007] The battery core comprises: a first composite current collector, a negative electrode material layer, a solid electrolyte separator, an electrode stack, a solid electrolyte separator, a positive electrode material layer, and a second composite current collector which are stacked in sequence;

[0008] The electrode stack comprises: a plurality of stacked positive and negative electrode sheet complexes, with a solid electrolyte membrane disposed between two adjacent positive and negative electrode complexes.

[0009] The solid-state cylindrical battery has a simple structure, a short production cycle, a low preparation cost, and has high energy density and voltage.

[0010] Another aspect of the present invention also relates to a method for preparing the solid-state cylindrical battery, comprising the following steps:

[0011] (a) stacking a first composite current collector, a negative electrode material layer, a solid electrolyte separator, an electrode stack, a solid electrolyte separator, a positive electrode material layer, and a second composite current collector in order to obtain a battery cell;

[0012] (b) connecting and packaging the battery core to an insulating shell.

[0013] The method for preparing the solid-state cylindrical battery is simple and easy to operate, does not require reliance on complex processes and equipment, and the prepared solid-state cylindrical battery has a higher voltage.

[0014] Another aspect of the present invention also relates to a cylindrical battery system, including the solid-state cylindrical battery or the solid-state cylindrical battery prepared by the preparation method of the solid-state cylindrical battery.

[0015] Another aspect of the present invention also relates to a vehicle, comprising the cylindrical battery system.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] (1) The solid-state cylindrical battery provided by the present invention forms a high-voltage cylindrical battery cell inside the insulating shell by stacking a plurality of positive and negative electrode sheet complexes, thereby realizing the high voltage of the single battery cell. Compared with the external series-parallel connection, the complexity of the present invention is reduced; the cylindrical battery has the characteristic of directional valve opening, which can realize the directional release of the runaway energy of the battery cell when thermal runaway occurs, reduce the impact on the passenger compartment when the battery cell runs away, and improve the overall safety of the battery system; by utilizing the insulating properties of the insulating shell, the entire shell of the single battery cell except the terminal is not charged, and the additional insulating components outside the battery cell can be eliminated, and the insulation protection measures that need to be performed at the system level when the battery cell is assembled into a battery system can also be omitted, thereby shortening the production cycle of the entire process of the battery system and reducing the cost of the battery system.

[0018] (2) The preparation method of the solid-state cylindrical battery provided by the present invention is simple and easy to operate, and does not rely on complex processes and equipment. The prepared solid-state cylindrical battery has high voltage and safety. The method uses a copper-aluminum composite current collector in the battery cell coating process, coats the positive electrode material on one side of the composite current collector and the negative electrode material on the other side, and then forms a circular positive and negative electrode sheet complex by rolling and punching the coated electrode sheets, and alternately stacks the positive and negative electrode sheet complexes and solid electrolyte membranes to form a battery cell stack, places the battery cell stack in a cylindrical insulating shell, and then connects the shell terminals to the battery cell stack. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A schematic structural diagram of a solid-state cylindrical battery cell provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The technical scheme of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments, but it will be understood by those skilled in the art that the following described embodiments are part of embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. If specific conditions are not specified in the embodiments, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not specified in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0022] One aspect of the present invention also relates to a solid-state cylindrical battery, such as Figure 1 As shown, it includes a battery core and an insulating shell arranged outside the battery core;

[0023] The battery core comprises: a first composite current collector, a negative electrode material layer, a solid electrolyte separator, an electrode stack, a solid electrolyte separator, a positive electrode material layer, and a second composite current collector which are stacked in sequence;

[0024] The electrode stack comprises: a plurality of stacked positive and negative electrode sheet complexes, with a solid electrolyte membrane disposed between two adjacent positive and negative electrode complexes.

[0025] The solid-state cylindrical battery forms a high-voltage cylindrical battery cell inside the insulating shell by stacking a plurality of positive and negative electrode sheet complexes, thereby realizing the high voltage of the single battery cell. Compared with the external series-parallel connection, the complexity of the present invention is reduced; the cylindrical battery has the characteristic of directional valve opening, which can realize the directional release of the runaway energy of the battery cell when the battery cell has thermal runaway, reduce the impact on the passenger compartment when the battery cell runs away, and improve the overall safety of the battery system; by utilizing the insulating properties of the insulating shell, the entire shell of the single battery cell except the terminal is not charged, and the additional insulating components outside the battery cell can be eliminated, and the insulation protection measures that need to be performed at the system level when the battery cell is assembled into a battery system can also be omitted, thereby shortening the production cycle of the entire process of the battery system and reducing the cost of the battery system.

[0026] The number of stacked positive and negative electrode sheet complexes can be adjusted according to the actual voltage requirements of the battery and is not specifically limited.

[0027] Furthermore, the positive and negative electrode sheet composite comprises: a copper-aluminum composite current collector and a positive electrode active material layer and a negative electrode active material layer respectively arranged on two surfaces of the copper-aluminum composite current collector.

[0028] Furthermore, the positive electrode active material layer is disposed on the aluminum surface of the copper-aluminum composite current collector. The present invention does not specifically limit the positive electrode active material of the positive electrode active material layer, and conventional positive electrode active materials in the art can be used to implement the technical solution of the present invention.

[0029] Furthermore, the negative electrode active material layer is disposed on the copper surface of the copper-aluminum composite current collector. The present invention does not specifically limit the negative electrode active material of the negative electrode active material layer, and conventional negative electrode active materials in the art can be used to implement the technical solution of the present invention.

[0030] During the stacking process, the positive and negative electrode sheet complexes remain in the same direction. The positive electrode active material layer at one end of the electrode stack obtained after stacking is close to the negative electrode material layer, and the negative electrode active material layer at the other end is close to the positive electrode material layer, so as to form a series structure inside the battery cell and increase the voltage of the single battery cell.

[0031] Furthermore, the insulating housing has terminals, and the battery cell is connected to the insulating housing via the terminals. The present invention does not specifically limit the material of the insulating housing, and any conventional insulating material in the art can be used to make the insulating housing.

[0032] Furthermore, the electrode stack includes at least two of the positive and negative electrode sheet composites. By stacking a plurality of positive and negative electrode sheet composites, the voltage of a single cell can be increased.

[0033] Furthermore, the shape of the battery cell includes but is not limited to: cylindrical.

[0034] Furthermore, the shape of the insulating shell includes but is not limited to: cylindrical.

[0035] A cylindrical insulating shell is sleeved over the cylindrical battery core to form a cylindrical solid-state battery, which is beneficial to improving the safety of the battery.

[0036] The present invention does not limit the specific types of the positive electrode material in the positive electrode material layer and the negative electrode material in the negative electrode material layer. Conventional positive electrode materials and negative electrode materials in the art can be used to implement the technical solution of the present invention.

[0037] Furthermore, the thickness of the first composite current collector is 4-30 μm, including but not limited to any point value of 4 μm, 10 μm, 15 μm, 20 μm, 25 μm or 30 μm, or a range value between any two of them.

[0038] Furthermore, the surface density of the negative electrode material layer is 50 to 120 g / m 2 , including but not limited to 50g / m 2 , 60g / m 2 , 70g / m 2 , 80g / m 2 , 90g / m 2 , 100g / m 2 , 110g / m 2 or 120g / m 2 Any point value in or any range of values ​​between them.

[0039] Furthermore, the thickness of the solid electrolyte membrane is 10 to 80 μm, including but not limited to any point value of 10 μm, 30 μm, 50 μm, 70 μm or 80 μm or a range value between any two of them.

[0040] Furthermore, the surface density of the positive electrode material layer is 130 to 330 g / m 2 , including but not limited to 130g / m 2 , 150g / m 2 , 180g / m 2 , 200g / m 2 , 240g / m 2 , 280g / m 2 , 300g / m 2 , 310g / m 2 , 320g / m 2 or 330g / m 2 Any point value in or any range of values ​​between them.

[0041] Furthermore, the thickness of the second composite current collector is 10-30 μm, including but not limited to any point value of 10 μm, 15 μm, 20 μm, 25 μm or 30 μm or a range value between any two of them.

[0042] Furthermore, the copper-aluminum composite current collector has a thickness of 14 to 30 μm, including but not limited to any point value of 14 μm, 20 μm, 25 μm or 30 μm or a range value between any two of them.

[0043] Furthermore, the surface density of the positive electrode active material layer is 130 to 330 g / m 2 , including but not limited to 130g / m 2 , 150g / m 2 , 180g / m 2 , 200g / m 2 , 240g / m 2 , 280g / m 2 , 300g / m 2 , 310g / m 2 , 320g / m 2 or 330g / m 2 Any point value in or any range of values ​​between them.

[0044] Furthermore, the surface density of the negative electrode active material layer is 50 to 120 g / m 2 , including but not limited to 50g / m 2 , 60g / m 2 , 70g / m 2 , 80g / m 2 , 90g / m 2 , 100g / m 2 , 110g / m 2 or 120g / m 2 Any point value in or any range of values ​​between them.

[0045] Limiting the thickness of each layer or surface density of the battery cell within a certain range is beneficial to improving the voltage and stability of the battery.

[0046] Another aspect of the present invention also relates to a method for preparing the solid-state cylindrical battery, comprising the following steps:

[0047] (a) stacking a first composite current collector, a negative electrode material layer, a solid electrolyte separator, an electrode stack, a solid electrolyte separator, a positive electrode material layer, and a second composite current collector in order to obtain a battery cell;

[0048] (b) connecting and packaging the battery core to an insulating shell.

[0049] The preparation method of the solid-state cylindrical battery uses a copper-aluminum composite current collector in the process of coating the battery cell, coats the positive electrode material on one side of the composite current collector and the negative electrode material on the other side, and then forms a circular positive and negative electrode sheet complex by rolling and punching the coated electrode sheets, and alternately stacks the positive and negative electrode sheet complexes and solid electrolyte membranes to form a battery cell stack, places the battery cell stack in a cylindrical insulating shell, and then connects the shell terminals to the battery cell stack.

[0050] The present invention adopts a copper-aluminum composite current collector, and coats the positive electrode material on one side of the composite current collector and the negative electrode material on the other side, and then forms a disc-shaped positive and negative electrode sheet complex by rolling and punching the coated electrode sheets, alternately stacking the positive and negative electrode sheet complexes and solid electrolyte membranes to form a battery cell stack, placing the battery cell stack in a cylindrical shell, and then connecting the shell to the battery cell stack to form an internally series-connected high-voltage cylindrical battery cell, thereby realizing the high voltage of the single battery cell and reducing the complexity of external series and parallel connections.

[0051] The present invention adopts a cylindrical form to encapsulate solid-state batteries, and utilizes the characteristic that cylindrical batteries can open valves in a directional manner to achieve directional release of the runaway energy of the battery cell when thermal runaway occurs, thereby reducing the impact on the passenger compartment when the battery cell runs away, and improving the overall safety of the battery system.

[0052] The present invention adopts a cylindrical insulating shell as the outer shell of the battery cell stack, and utilizes the insulating properties of the insulating shell to make the entire outer shell of the single battery cell, except for the terminal, non-charged, thereby eliminating additional insulating components outside the battery cell, such as insulating film, top patch, and can also omit insulating protection measures that need to be performed at the system level in the battery system when the battery cell is assembled, such as various insulating coatings or insulating films, thereby shortening the production cycle of the entire battery system and reducing the cost of the battery system.

[0053] In some specific embodiments, the method for preparing the solid-state cylindrical battery comprises the following steps:

[0054] S1: preparing a positive electrode active dressing and a negative electrode active dressing of a battery by stirring or fiberizing;

[0055] S2: Using coating or laminating methods, the positive electrode active dressing and the negative electrode active dressing are respectively attached to the two sides of the copper-aluminum composite current collector to form a battery electrode film roll A, wherein the positive electrode active dressing is attached to the aluminum side of the copper-aluminum composite current collector, and the negative electrode active dressing is attached to the copper side of the copper-aluminum composite current collector; another part of the electrode film roll B is prepared by only attaching the positive electrode active dressing to the aluminum side of the copper-aluminum composite current collector by coating or laminating methods; another part of the electrode film roll C is prepared by only attaching the negative electrode active dressing to the copper side of the copper-aluminum composite current collector by coating or laminating methods;

[0056] S3: Use rolling to improve the compaction degree of the prepared electrode membrane rolls A, B and C, so that the compaction density of the positive electrode active dressing is 2.4-3.7g / cm 3 The compaction density of the negative electrode active dressing is 1.2-1.8 g / cm 3 ;

[0057] S4: Slitting the prepared electrode membrane rolls A, B and C into strips by slitting;

[0058] S5: using a punching device to punch holes in the slit electrode film rolls A, B and C to form a disc-shaped positive and negative electrode sheet complex, a disc-shaped single-sided positive electrode sheet and a disc-shaped single-sided negative electrode sheet;

[0059] S6: punching the solid electrolyte membrane using a punching device to form a disc-shaped solid electrolyte membrane;

[0060] S7: stacking the disc-shaped single-sided negative electrode sheet, the disc-shaped solid electrolyte membrane, the disc-shaped positive and negative electrode sheet complex, the disc-shaped solid electrolyte membrane, and the disc-shaped positive and negative electrode sheet complex, and finally stacking the disc-shaped single-sided positive electrode sheet to form a battery cell;

[0061] S8: placing the battery cell in a cylindrical housing;

[0062] S9: Connect the cover plate to the battery cell and perform shell-cover plate packaging.

[0063] The present invention does not specifically limit the connection method between the cover plate and the battery cell, and any conventional connection method in the art can realize the technical solution of the present invention. In some specific embodiments, the connection method between the cover plate and the battery cell includes but is not limited to one of crimping, welding or conductive adhesive curing bonding.

[0064] Another aspect of the present invention also relates to a cylindrical battery system, including the solid-state cylindrical battery or the solid-state cylindrical battery prepared by the preparation method of the solid-state cylindrical battery.

[0065] Another aspect of the present invention also relates to a vehicle, comprising the cylindrical battery system.

[0066] The embodiments of the present invention will be described in detail below in conjunction with the examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. If no specific conditions are specified in the examples, the conditions are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be obtained commercially.

[0067] Example 1

[0068] The solid-state cylindrical battery provided in this embodiment includes a battery cell and an insulating shell arranged outside the battery cell; the insulating shell has a terminal, and the battery cell is connected to the insulating shell through the terminal;

[0069] The battery core comprises: a first composite current collector, a negative electrode material layer, a solid electrolyte separator, an electrode stack, a solid electrolyte separator, a positive electrode material layer, and a second composite current collector which are stacked in sequence;

[0070] The electrode stack includes: a plurality of stacked positive and negative electrode sheet composites, with a solid electrolyte membrane disposed between two adjacent positive and negative electrode composites;

[0071] The positive and negative electrode sheet composite comprises: a copper-aluminum composite current collector and a positive electrode active material layer and a negative electrode active material layer respectively arranged on two surfaces of the copper-aluminum composite current collector; the positive electrode active material layer is arranged on the aluminum surface of the copper-aluminum composite current collector; the negative electrode active material layer is arranged on the copper surface of the copper-aluminum composite current collector;

[0072] The electrode stack includes 127 positive and negative electrode sheet complexes;

[0073] The thickness of the first composite current collector is 16 μm; the surface density of the negative electrode material layer is 100 g / m 2 ; The thickness of the solid electrolyte membrane is 30μm; the surface density of the positive electrode material layer is 225g / m 2 ; The thickness of the second composite current collector is 16 μm;

[0074] The thickness of the copper-aluminum composite current collector is 16 μm; the surface density of the positive electrode active material layer is 225 g / m 2 ; The surface density of the negative electrode active material layer is 100g / m 2 .

[0075] Example 2

[0076] The solid-state cylindrical battery provided in this embodiment is different from that in Embodiment 1 only in that the electrode stack includes 95 positive and negative electrode sheet composites;

[0077] The thickness of the first composite current collector is 4 μm; the surface density of the negative electrode material layer is 50 g / m 2 ; The thickness of the solid electrolyte membrane is 10μm; the surface density of the positive electrode material layer is 130g / m 2 ; The thickness of the second composite current collector is 10 μm;

[0078] The thickness of the copper-aluminum composite current collector is 14 μm; the surface density of the positive electrode active material layer is 130 g / m 2 ; The surface density of the negative electrode active material layer is 50g / m 2 .

[0079] Example 3

[0080] The solid-state cylindrical battery provided in this embodiment is different from that in Embodiment 1 only in that the electrode stack includes 195 positive and negative electrode sheet composites;

[0081] The thickness of the first composite current collector is 30 μm; the surface density of the negative electrode material layer is 120 g / m 2 ; The thickness of the solid electrolyte membrane is 80μm; the surface density of the positive electrode material layer is 330g / m 2 ; The thickness of the second composite current collector is 30 μm;

[0082] The thickness of the copper-aluminum composite current collector is 30 μm; the surface density of the positive electrode active material layer is 330 g / m 2 ; The surface density of the negative electrode active material layer is 120g / m 2 .

[0083] Example 4

[0084] The method for preparing a solid-state cylindrical battery provided in this embodiment is used to prepare the solid-state cylindrical batteries of Embodiments 1 to 3, and comprises the following steps:

[0085] S1: preparing a positive electrode active dressing and a negative electrode active dressing of a battery by stirring or fiberization;

[0086] S2: The positive electrode active dressing and the negative electrode active dressing are respectively attached to the two sides of the copper-aluminum composite current collector by coating or laminating to form a battery electrode film roll A, wherein the positive electrode active dressing is attached to the aluminum side of the copper-aluminum composite current collector, and the negative electrode active dressing is attached to the copper side of the copper-aluminum composite current collector; and a portion of the electrode film roll B in which the positive electrode active dressing is attached only to the aluminum side of the copper-aluminum composite current collector by coating or laminating and a portion of the electrode film roll C in which the negative electrode active dressing is attached only to the copper side of the copper-aluminum composite current collector by coating or laminating are prepared;

[0087] S3: improving the compaction degree of the prepared electrode membrane rolls A, B, and C by rolling;

[0088] S4: Slitting the prepared electrode membrane rolls A, B, and C into strips;

[0089] S5: using a punching device to punch holes in the slit electrode film rolls A, B, and C to form a disc-shaped positive and negative electrode sheet composite, a disc-shaped positive electrode material and a second composite current collector composite, and a disc-shaped first composite current collector and a negative electrode material layer composite;

[0090] S6: punching the solid electrolyte membrane using a punching device to form a disc-shaped solid electrolyte membrane;

[0091] S7: stacking a combination of a disc-shaped first composite current collector and a negative electrode material layer, a disc-shaped solid electrolyte membrane, a plurality of disc-shaped positive and negative electrode sheet composites, and a plurality of disc-shaped solid electrolyte membranes in sequence, and finally stacking a combination of a disc-shaped positive electrode material and a second composite current collector to form a battery cell;

[0092] S8: placing the battery cell in a cylindrical housing;

[0093] S9: Connect the cover plate to the battery cell stack and perform shell-cover plate packaging.

[0094] Comparative Example 1

[0095] The solid cylindrical battery provided in this comparative example comprises a battery cell and a steel shell arranged outside the battery cell; the steel shell is provided with a terminal, and the battery cell is connected to the steel shell through the terminal; the battery cell comprises: an electrode winding body wound in sequence;

[0096] The electrode winding body comprises: a plurality of positive electrode sheets and negative electrode sheets which are wound together, and a solid electrolyte separator is arranged between two adjacent positive and negative electrode sheets;

[0097] The positive electrode sheet comprises: an aluminum current collector and positive electrode active material layers respectively arranged on two surfaces of the aluminum current collector;

[0098] The negative electrode sheet comprises: a copper current collector and negative electrode active material layers respectively arranged on two surfaces of the copper current collector;

[0099] The electrode winding body includes one solid electrolyte membrane, one negative electrode sheet, one solid electrolyte membrane, and one positive electrode sheet in sequence;

[0100] The thickness of the solid electrolyte separator is 30 μm; the thickness of the copper current collector is 4 μm; the surface density of the negative electrode material layer is 100 g / m 2 ; The thickness of the aluminum current collector is 12μm; the surface density of the positive electrode material layer is 225g / m 2 .

[0101] Comparative Example 2

[0102] The method for preparing a solid-state cylindrical battery provided in this comparative example is used to prepare the solid-state cylindrical battery of comparative example 1, comprising the following steps:

[0103] S1: preparing a positive electrode active dressing and a negative electrode active dressing of a battery by stirring or fiberization;

[0104] S2: attaching the positive electrode active dressing to both sides of the aluminum current collector by coating or laminating to form a battery positive electrode film roll D, and attaching the negative electrode active dressing to both sides of the copper current collector to form a battery negative electrode film roll E;

[0105] S3: using rolling to improve the compaction degree of the prepared electrode membrane rolls D and E;

[0106] S4: Slitting the prepared electrode membrane rolls D and E into strips by slitting;

[0107] S5: using a device to divide the solid electrolyte membrane into strip-shaped solid electrolyte membranes;

[0108] S6: stacking the strip-shaped solid electrolyte membrane, the strip-shaped negative electrode sheet, the strip-shaped solid electrolyte membrane, and the strip-shaped positive electrode sheet in order and winding them together to form a battery cell;

[0109] S7: placing the battery cell in a cylindrical housing;

[0110] S8: Connect the cover plate to the battery cell stack and perform shell-cover plate packaging.

[0111] Experimental example

[0112] The voltage and energy density of the solid-state cylindrical batteries provided in the embodiments and comparative examples were tested. The voltage test method was to directly measure the fully charged battery cell using a voltage internal resistance tester. The energy density test method was to perform a 1 / 3C 100% DOD energy test on the battery using a charger and discharger. The average value of three tests was taken and then divided by the weight of the battery cell. The test results are shown in Table 1.

[0113] Table 1

[0114] Voltage / V Energy densityWh / kg Example 1 435 185 Example 2 326 130 Example 3 666 185 Comparative Example 1 3.4 185

[0115] It can be seen from Table 1 that the battery prepared by the method of the present invention can obtain a higher voltage while having the same energy density.

[0116] Although the present invention has been illustrated and described with specific embodiments, it should be appreciated that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Those skilled in the art should understand that the technical solutions described in the above embodiments may be modified, or some or all of the technical features thereof may be replaced by equivalents without departing from the spirit and scope of the present invention. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention. Therefore, this means that all such replacements and modifications within the scope of the present invention are included in the appended claims.

Claims

1. A solid cylindrical battery, characterized in that: It includes a battery core and an insulating shell arranged outside the battery core; The battery core comprises: a first composite current collector, a negative electrode material layer, a solid electrolyte separator, an electrode stack, a solid electrolyte separator, a positive electrode material layer, and a second composite current collector which are stacked in sequence; The electrode stack comprises: a plurality of stacked positive and negative electrode sheet complexes, with a solid electrolyte membrane disposed between two adjacent positive and negative electrode complexes.

2. The solid-state cylindrical battery according to claim 1, characterized in that: The positive and negative electrode sheet composite comprises: a copper-aluminum composite current collector and a positive electrode active material layer and a negative electrode active material layer respectively arranged on two surfaces of the copper-aluminum composite current collector.

3. The solid-state cylindrical battery according to claim 2, characterized in that: The positive electrode active material layer is disposed on the aluminum surface of the copper-aluminum composite current collector; And / or, the negative electrode active material layer is arranged on the copper surface of the copper-aluminum composite current collector.

4. The solid-state cylindrical battery according to claim 1, characterized in that: The insulating shell is provided with a terminal, and the battery core is connected to the insulating shell via the terminal.

5. The solid-state cylindrical battery according to claim 1, characterized in that: The electrode stack includes at least two positive and negative electrode sheet composites.

6. The solid-state cylindrical battery according to claim 1, characterized in that: Includes at least one of the following technical features: (1) The thickness of the first composite current collector is 4 to 30 μm; (2) The surface density of the negative electrode material layer is 50 to 120 g / m 2 ; (3) The thickness of the solid electrolyte membrane is 10 to 80 μm; (4) The surface density of the positive electrode material layer is 130 to 330 g / m 2 ; (5) The thickness of the second composite current collector is 10 to 30 μm.

7. The solid-state cylindrical battery according to claim 2, characterized in that: Includes at least one of the following technical features: (1) The thickness of the copper-aluminum composite current collector is 14 to 30 μm; (2) The surface density of the positive electrode active material layer is 130 to 330 g / m 2 ; (3) The surface density of the negative electrode active material layer is 50 to 120 g / m 2 .

8. The method for preparing a solid cylindrical battery according to any one of claims 1 to 7, characterized in that: The following steps are involved: (a) stacking a first composite current collector, a negative electrode material layer, a solid electrolyte separator, an electrode stack, a solid electrolyte separator, a positive electrode material layer, and a second composite current collector in order to obtain a battery cell; (b) connecting and packaging the battery core to an insulating shell.

9. A cylindrical battery system, characterized in that: A solid-state cylindrical battery comprising the solid-state cylindrical battery according to any one of claims 1 to 7 or a solid-state cylindrical battery prepared by the preparation method of the solid-state cylindrical battery according to claim 8.

10. A vehicle, characterized in that: A cylindrical battery system comprising the method of claim 9.

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