All-solid-state square-shell lithium ion battery

Abstract

The utility model relates to the technical field of solid-state batteries, and particularly discloses an all-solid-state square-shell lithium ion battery which comprises a shell, a pressing plate, a bottom plate, a cover plate, a roll core, a negative busbar, a positive busbar and two liquid guide fastening core rods, the length, the height and the thickness of the roll core are L2, H2 and T2 in sequence, L2 is more than or equal to 10mm and less than or equal to 2000mm, H2 is more than or equal to 10mm and less than or equal to 200mm, and T2 is more than or equal to 10mm and less than or equal to 200mm; the thickness T3 of the shell is more than or equal to 0.2 mm and less than or equal to 8 mm; and the length, the outer diameter and the inner diameter of the drainage fastening core rod are L3, D1 and D2 in sequence, L3 is more than or equal to 100mm and less than or equal to 2000mm, D1 is more than or equal to 4.5 mm and less than or equal to 10mm, and D2 is more than or equal to 4.1 mm and less than or equal to 9.6 mm. The length of the battery cell can reach 10-2000mm, the grouping is simple and efficient, and the battery cell is expected to be widely applied to the fields of electric automobiles, energy storage systems and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of solid-state batteries, in particular to an all-solid-state square-shell lithium-ion battery. Background Art

[0002] Soft-pack all-solid-state lithium batteries are a new type of battery technology. They utilize a solid-state electrolyte that is virtually non-flammable, reducing the battery pack's sensitivity to temperature and eliminating the risk of lithium dendrites and short circuits caused by lithium deposition. Furthermore, in the event of thermal runaway, the soft-pack battery's aluminum-plastic film casing will first swell and break through the seal, dissipating significant heat and preventing explosion. Furthermore, their high energy density, fast charge and discharge rates, flexible design, and environmental sustainability have garnered widespread attention and research in recent years.

[0003] However, the above-mentioned soft-pack all-solid-state lithium battery also has some challenges that limit its application and promotion. In particular, due to the limitations of the aluminum-plastic film, the thickness of the soft-pack battery cell cannot be too large, which makes it difficult to make the battery cell larger. At present, the length of the soft-pack battery cell is limited to 500-600mm. In addition, it is difficult to group it, the grouping efficiency is low, and it is difficult to apply the pressure required for the all-solid-state battery after grouping. Therefore, the solid-solid contact is low, the battery internal resistance is high, and the rate performance is poor. In addition, since there is no liquid cooling channel inside, the heat dissipation capacity of the battery cell is poor. There is often a temperature difference of 10-20°C between the internal temperature of the battery cell and the external temperature. Especially during high-rate charge and discharge, the actual temperature difference may be even greater. The soft-pack all-solid-state laminated lithium battery has poor temperature control performance and is prone to thermal runaway, resulting in poor cycle performance and short cycle life.

[0004] For this purpose, this application is filed. Utility Model Content

[0005] In view of the above-mentioned shortcomings of the prior art, the present invention provides an all-solid-state square-shell lithium-ion battery.

[0006] In order to achieve the above-mentioned purpose, the main technical solutions adopted by this utility model include:

[0007] An all-solid-state square-shell lithium-ion battery, comprising: a shell, a pressing plate, a bottom plate, a cover plate, a winding core, a negative electrode bus bar, a positive electrode bus bar, and two liquid-conducting fastening core rods;

[0008] The length, height and thickness of the core are L2, H2 and T2 in order, 10mm≤L2≤2000mm, 10mm≤H2≤200mm, 10mm≤T2≤200mm;

[0009] The shell is a metal square shell with two ends open. The thickness of the square shell is T3, 0.2mm≤T3≤8mm. The length, height and thickness of the square shell match the length, height and thickness of the winding core.

[0010] The length, outer diameter and inner diameter of the liquid-guiding fastening mandrel are L3, D1 and D2 in sequence, 100mm≤L3≤2000mm, 4.5mm≤D1≤10mm, 4.1mm≤D2≤9.6mm;

[0011] The pressure plate and the base plate are arranged opposite to and parallel to each other, the two ends of the liquid-conducting fastening core rod are respectively vertically connected to the pressure plate and the base plate and are connected to the outside world, the winding core is stacked on the two liquid-conducting fastening core rods and the upper and lower ends are pressed by the pressure plate and the base plate, the left and right sides of the winding core are respectively provided with negative pole ears and positive pole ears, the cover plate is provided on the pressure plate and the positive pole column and negative pole column of the cover plate are respectively connected to the positive pole bus and the negative pole bus, the negative pole bus and the positive pole bus are respectively welded to the negative pole ear and the positive pole ear, the shell is sleeved outside the winding core and one end is connected to the cover plate seal and the other end is connected to the base plate seal.

[0012] Furthermore, the pressure plate includes a pressure plate body, the upper surface of which is provided with hollow reinforcing ribs, and the pressure plate body is provided with a through hole I for the liquid-conducting fastening core rod to pass through, and the inner diameter of the through hole I matches the outer diameter of the liquid-conducting fastening core rod.

[0013] Furthermore, two second through holes are provided on the bottom plate, and two first through holes are provided on the cover plate. One end of the two liquid-conducting fastening core rods is seamlessly connected to the second through holes, and the other end is seamlessly connected to the first through holes.

[0014] Furthermore, the two second through holes are symmetrically distributed on the bottom plate, and the two first through holes are symmetrically distributed on the cover plate.

[0015] Furthermore, the middle portion of the lower surface of the cover plate is raised, and after the two sides of the raised portion are welded to the negative electrode bus bar and the positive electrode bus bar, the raised portion is in close contact with the pressing plate.

[0016] Furthermore, the winding core includes stacked negative electrode sheets, positive electrode sheets and all-solid-state electrolyte membranes, the positive electrode tabs and negative electrode tabs are respectively arranged on one side of the positive electrode sheet and the negative electrode sheet, the positive electrode tabs and the negative electrode tabs are respectively provided with second long strip holes and first long strip holes distributed along their respective width directions, the positive electrode tabs and the negative electrode tabs are respectively located on opposite sides of the winding core, the negative electrode bus is inserted into several first long strip holes and welded to the negative electrode tabs, and the positive electrode bus is inserted into several second long strip holes and welded to the positive electrode tabs.

[0017] Furthermore, the negative electrode plate includes a negative electrode current collector, which is divided into a negative electrode active material coating area and a foil area. The foil area forms a negative electrode tab. Two vias III are provided on the negative electrode active material coating area. The negative electrode tab is 10-200 mm long and 5-50 mm wide. The first long strip hole is 5-100 mm long and 1-10 mm wide. The negative electrode active material coating area is 10-600 mm long, 10-200 mm wide, and 10-400 μm thick. The diameter of the via III is 5-20 mm. The positive electrode plate has the same structure as the negative electrode plate, and the all-solid-state electrolyte membrane has the same structure as the negative electrode active material coating area.

[0018] Furthermore, both the negative busbar and the positive busbar are T-shaped structures, and the T-shaped structure includes a horizontal section and a vertical section. The vertical section of the negative busbar is inserted into the first elongated hole and welded to the negative electrode tab lying thereon, and the vertical section of the positive busbar is inserted into the second elongated hole and welded to the positive electrode tab lying thereon, and the horizontal section of the negative busbar and the horizontal section of the positive busbar are both welded to the cover plate.

[0019] Furthermore, the horizontal section is 2-50 mm higher than the upper surface of the winding core and higher than the upper surface of the pressing plate.

[0020] Specifically, the length, height, and thickness of the all-solid-state square-shell lithium-ion battery are L1, H1, and T1, respectively, and 10 mm ≤ L1 ≤ 2000 mm, 10 mm ≤ H1 ≤ 200 mm, and 10 mm ≤ T1 ≤ 200 mm.

[0021] Compared with the prior art, the present invention has at least the following beneficial effects:

[0022] 1. The addition of a liquid-guiding and fastening core rod effectively improves the heat dissipation performance of the battery, solves the problem of excessively high internal temperature of the battery during high-rate charge and discharge, and reduces the temperature difference between the internal and external temperatures of the battery cell, which also helps to increase the cycle life of the battery cell;

[0023] 2. The structural design of the liquid-guiding and fastening core rod forms a constraint on the inside of the winding core, and the structural design of the pressure plate and bottom plate forms a pressure on the winding core. The dual effects of constraint and pressure can not only enhance the solid-solid contact inside, help reduce the internal resistance of the battery and improve the battery cycle rate performance, but also inhibit the expansion of the battery cell and extend the cycle life of the battery;

[0024] 3. The tabs are inverted on the busbar, which optimizes the tab welding form and solves the problem of the tabs being too thick and inconvenient to weld in laminated batteries. This not only reduces the difficulty of tab welding, but also helps to increase the upper limit of the number of laminates and the upper limit of capacity.

[0025] 4. The use of square aluminum shell packaging not only reduces the difficulty of all-solid-state battery grouping, making its assembly operation simple and efficient, but also improves the safety of the battery and helps to increase the overall energy density of the PACK;

[0026] 5. The length of the battery cell can be 10-2000mm and the thickness can be 10-200mm, which far exceeds the existing soft-pack all-solid-state batteries and is expected to be widely used in electric vehicles, energy storage systems and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0028] Figure 1 This is a schematic diagram of the explosion structure of the all-solid-state square shell lithium-ion battery proposed in the present utility model;

[0029] Figure 2 This is the appearance of the all-solid-state square-shell lithium-ion battery proposed in this utility model;

[0030] Figure 3 for Figure 1 Schematic diagram of the connection between the midsole plate and the liquid-guiding fastening core rod;

[0031] Figure 4 for Figure 1 Schematic diagram of the assembly of the middle winding core;

[0032] Figure 5 for Figure 1 Schematic diagram of the structure of the middle winding core;

[0033] Figure 6 for Figure 1 Schematic diagram of the connection relationship between the middle winding core, pressure plate, negative bus bar, and positive bus bar;

[0034] Figure 7 for Figure 6 Schematic diagram of the enlarged structure at A in the middle;

[0035] Figure 8 for Figure 1 Schematic diagram of the structure of the medium pressure plate;

[0036] Figure 9 for Figure 4 Schematic diagram of the structure of the negative electrode;

[0037] Figure 10 for Figure 4 Schematic diagram of the structure of the all-solid-state electrolyte membrane.

[0038] In the figure: 1. Shell; 2. Pressing plate; 21. Pressing plate body; 22. Reinforcing rib; 23. Via hole I; 3. Bottom plate; 4. Cover plate; 5. Winding core; 51. Negative electrode sheet; 511. Negative electrode tab; 512. First long hole; 513. Negative electrode active material coating area; 514. Via hole III; 52. Positive electrode sheet; 521. Positive electrode tab; 522. Second long hole; 53. All-solid-state electrolyte membrane; 531. Via hole II; 6. Negative electrode bus; 7. Positive electrode bus; 8. Liquid-guiding fastening core rod. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, and are not all embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0040] The structures not described in detail in the following embodiments are all prior art, and the directional words such as "upper surface", "lower surface", "bottom surface", "upper and lower ends", "left and right sides" used to clearly describe the component structure are only used to describe their relative positional relationship and are not used to limit the scope of protection of the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" can explicitly or implicitly include at least one of such features. In the description of the present utility model, the meaning of "several" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0041] like Figures 1-10 Commonly shown: An all-solid-state square shell lithium-ion battery, comprising: a shell 1, a pressure plate 2, a bottom plate 3, a cover plate 4 (which is similar to the cover plate of an existing square battery and specifically includes necessary structures such as a positive electrode column, a negative electrode column, and a pressure relief valve), a winding core 5, a negative electrode bus bar 6, a positive electrode bus bar 7, and two liquid-conducting fastening core rods 8;

[0042] The length, height, and thickness of the winding core 5 are L2, H2, and T2, respectively, 10 mm ≤ L2 ≤ 2000 mm, 10 mm ≤ H2 ≤ 200 mm, and 10 mm ≤ T2 ≤ 200 mm;

[0043] The housing 1 is a square metal housing with two open ends, such as an aluminum square housing, a steel square housing, a copper alloy square housing, a magnesium alloy square housing, etc., preferably obtained by integrated extrusion molding. The thickness of the square housing is T3, 0.2mm≤T3≤8mm, and the length, height, and thickness of the square housing match the length, height, and thickness of the winding core 5;

[0044] The length, outer diameter and inner diameter of the liquid-guiding fastening core rod 8 are L3, D1 and D2 in sequence, 100 mm ≤ L3 ≤ 2000 mm, 4.5 mm ≤ D1 ≤ 10 mm, and 4.1 mm ≤ D2 ≤ 9.6 mm;

[0045] The pressure plate 2 and the bottom plate 3 are arranged opposite to and parallel to each other, and the two ends of the liquid-conducting fastening core rod 8 are respectively vertically connected to the pressure plate 2 and the bottom plate 3 and connected to the outside world. The winding core 5 is stacked on the two liquid-conducting fastening core rods 8 and the upper and lower ends are pressed by the pressure plate 2 and the bottom plate 3. The left and right sides of the winding core 5 are respectively provided with a negative electrode tab 511 and a positive electrode tab 521. The cover plate 4 is covered on the pressure plate 2 and the positive electrode column and the negative electrode column of the cover plate 4 are respectively connected to the positive electrode bus 7 and the negative electrode bus 6. The negative electrode bus 6 and the positive electrode bus 7 are respectively welded to the negative electrode tab 511 and the positive electrode tab 521. The shell 1 is sleeved on the outside of the winding core 5 and one end is sealed and connected to the cover plate 4 (welded or riveted), and the other end is sealed and connected to the bottom plate 3 (welded or riveted).

[0046] Through the above structural design: coolant is passed into the liquid-conducting and fastening core rod 8, which can realize rapid liquid cooling of the battery cell, improve the heat dissipation performance of the battery cell, solve the problem of excessive internal temperature of the battery during high-rate charge and discharge, reduce the temperature difference between the internal temperature of the battery cell and the external temperature, and improve the cycle life of the battery cell; the cover plate 4 and the bottom plate 3 form a pressurizing mechanism, and the two liquid-conducting and fastening core rods 8 form a constraint inside the winding core 5. The dual effects of extrusion and constraint enhance the solid-solid contact inside the winding core 5, which not only helps to reduce the internal resistance of the battery and improve the battery cycle rate performance, but also inhibits the expansion of the battery cell and improves the cycle life of the battery.

[0047] Compared with traditional soft-pack batteries, the utility model is equipped with a pressurizing mechanism for squeezing the core 5 and a liquid-conducting fastening core rod 8 for restraining the core 5 and having a liquid cooling function, thereby improving the electrochemical performance of the battery; it is packaged with a hard shell 1, and the appearance is more regular, which helps to reduce the difficulty of grouping and improve the efficiency of grouping. The synergistic effect helps to improve the overall energy density of the PACK and the safety of the battery, and is more suitable for the development needs of solid-state batteries.

[0048] In this embodiment, the preparation of the all-solid-state square-shell lithium-ion battery mainly includes the following steps:

[0049] The first step is to relatively fix the two liquid-conducting fastening core rods 8 on the bottom plate 3. After fixation, the bottom ends of the two liquid-conducting fastening core rods 8 are exposed through the bottom plate 3 and then communicated with the outside world;

[0050] Step 2: Insert the all-solid electrolyte membrane 53, the positive electrode sheet 52, and the negative electrode sheet 51 from the top of the liquid-conducting fastening core rod 8 and stack them. The laminated sheets are arranged on them to form a winding core 5. The negative electrode tab 511 and the positive electrode tab 521 are distributed on the left and right sides of the winding core 5.

[0051] Step 3: First, insert the pressing plate 2 from the top of the liquid-guiding fastening core rod 8 and press it onto the top of the winding core 5 with the help of external force. Then, weld the pressing plate 2 to the liquid-guiding fastening core rod 8 to fix the position of the pressing plate 2 and squeeze the winding core 5.

[0052] Step 4: Connect the negative electrode busbar 6 and the positive electrode busbar 7 to the negative electrode tab 511 and the positive electrode tab 521 respectively. Specifically, weld the large surface of the busbar to the tab.

[0053] Step 5: Place the cover plate 4 on the pressure plate 2. The negative electrode column and the positive electrode column of the cover plate 4 are welded to the negative bus bar 6 and the positive bus bar 7 respectively. The top end of the liquid-guiding fastening core rod 8 is exposed through the cover plate 4 and then communicated with the outside world.

[0054] Step 6: Put the shell 1 outside the winding core 5, and seamlessly connect one end of the shell 1 to the cover plate 4 through laser welding or riveting, and seamlessly connect the other end of the shell 1 to the bottom plate 3 through laser welding or riveting.

[0055] As a preferred technical solution, in another embodiment of the present utility model, the pressure plate 2 includes a pressure plate body 21, the upper surface of the pressure plate body 21 is provided with a hollow reinforcing rib 22, and the pressure plate body 21 is provided with a through hole Ⅰ 23 for the liquid-conducting fastening core rod 8 to pass through, and the inner diameter of the through hole Ⅰ 23 matches the outer diameter of the liquid-conducting fastening core rod 8.

[0056] In this embodiment, the reinforcing rib 22 is designed as a hollow structure mainly to improve the strength of the pressure plate body 21 and enhance the battery energy density without increasing the weight of the pressure plate body 21 too much. Its specific shape is not limited, and the size specifications can be flexibly designed according to actual needs.

[0057] As a preferred technical solution, in another embodiment of the present utility model, two second through holes are provided on the base plate 3, and two first through holes are provided on the cover plate 4. One end of the two liquid-conducting fastening core rods 8 is seamlessly welded to the second through hole, and the other end is seamlessly welded to the first through hole. After welding, the two ends of the two liquid-conducting fastening core rods 8 are connected to the outside world through the second through hole and the first through hole respectively.

[0058] As a preferred technical solution, in another embodiment of the present utility model, the two second through holes are symmetrically distributed on the bottom plate 3 , and the two first through holes are symmetrically distributed on the cover plate 4 .

[0059] The positions of the first through hole and the second through hole determine the distribution of the liquid-conducting fastening core rod 8 in the winding core 5. The liquid-conducting fastening core rod 8 is symmetrically distributed in the winding core 5. On the one hand, a good liquid cooling effect can be obtained to improve the temperature control performance of the battery. On the other hand, the restraining force on the winding core 5 is evenly distributed. Under the synergistic effect of the pressurization of the bottom plate 3 and the cover plate 4, the solid-solid contact degree in the winding core 5 is high and the expansion rate is low, the internal resistance of the battery is small, the cycle rate performance of the battery is good, and the cycle life is long.

[0060] As a preferred technical solution, in another embodiment of the present invention, the middle part of the lower surface of the cover plate 4 is raised, and after the two sides of the raised part are welded to the negative bus 6 and the positive bus 7, the raised part is in close contact with the pressure plate 2, further improving the stability of the entire battery structure.

[0061] As a preferred technical solution, another embodiment of the present invention, the winding core 5 includes a stacked negative electrode sheet 51, a positive electrode sheet 52 and an all-solid-state electrolyte membrane 53, the positive electrode tab 521 and the negative electrode tab 511 are respectively arranged on one side of the positive electrode sheet 52 and the negative electrode sheet 51, and the positive electrode tab 521 and the negative electrode tab 511 are respectively provided with a second long strip hole 522 and a first long strip hole 512 distributed along their respective width directions. The positive electrode tab 521 and the negative electrode tab 511 are respectively located on opposite sides of the winding core 5, the negative electrode bus 6 is inserted into several first long strip holes 512 and welded to the negative electrode tab 511, and the positive electrode bus 7 is inserted into several second long strip holes 522 and welded to the positive electrode tab 521.

[0062] In this embodiment, the stacked structure of the negative electrode sheet 51, the positive electrode sheet 52 and the all-solid-state electrolyte membrane 53 is: all-solid-state electrolyte membrane 53, the positive electrode sheet 52 (or the negative electrode sheet 51), the all-solid-state electrolyte membrane 53, the negative electrode sheet 51 (or the positive electrode sheet 52), and the all-solid-state electrolyte membrane 53 is an existing technology and has the functions of both electrolyte and diaphragm.

[0063] In this embodiment, the specific shapes of the second elongated holes 522 and the first elongated holes 512 are not limited, and the methods of obtaining them are not limited. They can be rectangular elongated holes, waist-shaped elongated holes, or other existing structures that can meet the requirements of bus insertion.

[0064] In this embodiment, the second elongated hole 522 and the first elongated hole 512 are preferably arranged inwards, so as to leave a larger welding space on the tab and achieve a stable connection between the tab and the large surface of the busbar.

[0065] As a preferred technical solution, in another embodiment of the present invention, the negative electrode sheet 51 includes a negative electrode current collector, preferably copper foil. The negative electrode current collector is divided into a negative electrode active material coating area 513 and a foil area. The foil area forms a negative electrode tab 511. Two vias III 514 are provided on the negative electrode active material coating area 513. The negative electrode tab 511 is 10-200 mm long and 5-50 mm wide. The first elongated hole 512 is 5-100 mm long and 1-10 mm wide. The negative electrode active material coating area 513 is 10-600 mm long, 10-200 mm wide, and 10-400 μm thick. The diameter of the via III 514 is 5-20 mm.

[0066] The positive electrode sheet 52 includes a positive electrode current collector, preferably aluminum foil. The positive electrode current collector is divided into a positive electrode active material coating area and a foil area. The foil area forms a positive electrode tab 521. The positive electrode active material coating area is provided with two vias, each with a diameter of 5-20 mm. The positive electrode tab 521 is 10-200 mm long and 5-50 mm wide. The second elongated hole 522 is 5-100 mm long and 1-10 mm wide. The positive electrode active material coating area is 10-600 mm long, 10-200 mm wide, and 10-400 μm thick.

[0067] The all-solid electrolyte membrane 53 is 10-600 mm long, 10-200 mm wide, and 10-400 μm thick, and is provided with two via holes II 531 , each of which has a diameter of 5-20 mm.

[0068] As a preferred technical solution, in another embodiment of the present invention, the negative bus bar 6 and the positive bus bar 7 are both T-shaped structures, and the T-shaped structure includes a horizontal section and a vertical section. The T-shaped structure of the bus bar not only facilitates the operation of inserting it into several layers of the long strip holes of the pole tabs, but also facilitates contact with the cover plate 4 for welding, thereby improving the stability of the winding core 5 in the shell 1; the vertical section of the negative bus bar 6 is inserted into the first long strip hole 512 and welded to the negative pole tab 511 lying thereon, and the vertical section of the positive bus bar 7 is inserted into the second long strip hole 522 and welded to the positive pole tab 521 lying thereon, and the horizontal section of the negative bus bar 6 and the horizontal section of the positive bus bar 7 are both welded to the cover plate 4.

[0069] In this embodiment, after the busbar is inserted into the elongated hole, the tabs are technically inverted onto the busbar. The specific form of inversion is not limited. For example, the tabs can be inverted downward, upward, or even divided into two equal parts, one downward and the other upward, forming a symmetrical inversion. Inversion can reduce the thickness of the tabs and form staggered welding positions, solving the problem of tabs being too thick and inconvenient to weld in laminated batteries. It not only reduces the difficulty of tab welding, but also helps to increase the upper limit of the number of stacked cells and the upper limit of capacity.

[0070] As a preferred technical solution, in another embodiment of the present invention, the horizontal section is 2-50 mm higher than the upper surface of the winding core 5 and higher than the upper surface of the pressing plate 2 so as to be welded to the positive and negative poles of the cover plate 4.

[0071] As a preferred technical solution, in another embodiment of the present utility model, the length, height and thickness of the all-solid-state square shell lithium-ion battery are L1, H1 and T1, respectively, 10mm≤L1≤2000mm, 10mm≤H1≤200mm, and 10mm≤T1≤200mm.

[0072] Although the embodiments of the present invention have been shown and described above, it should be understood that the above embodiments are illustrative and should not be construed as limiting the present invention. Those skilled in the art may modify, alter, replace, and distort the above embodiments within the scope of the present invention. Furthermore, those skilled in the art may combine and incorporate the different embodiments or examples described in this specification, as well as features of the different embodiments or examples, without conflicting with each other.

Claims

1. An all-solid-state square-shell lithium-ion battery, characterized in that: include: A shell (1), a pressure plate (2), a bottom plate (3), a cover plate (4), a winding core (5), a negative electrode bus bar (6), a positive electrode bus bar (7) and two liquid-conducting fastening core rods (8); The length, height and thickness of the winding core (5) are L2, H2 and T2 in sequence, 10mm≤L2≤2000mm, 10mm≤H2≤200mm, 10mm≤T2≤200mm; The shell (1) is a metal square shell with openings at both ends. The thickness of the square shell is T3, 0.2 mm ≤ T3 ≤ 8 mm. The length, height and thickness of the square shell match the length, height and thickness of the winding core (5). The length, outer diameter and inner diameter of the liquid-guiding fastening core rod (8) are L3, D1 and D2 in sequence, 100 mm ≤ L3 ≤ 2000 mm, 4.5 mm ≤ D1 ≤ 10 mm, and 4.1 mm ≤ D2 ≤ 9.6 mm; The pressing plate (2) and the bottom plate (3) are arranged opposite to and in parallel with each other. The two ends of the liquid-conducting fastening core rod (8) are respectively connected vertically to the pressing plate (2) and the bottom plate (3) and are in communication with the outside. The winding core (5) is stacked on the two liquid-conducting fastening core rods (8) and the upper and lower ends are pressed by the pressing plate (2) and the bottom plate (3). The left and right sides of the winding core (5) are respectively provided with a negative electrode tab (511) and a positive electrode tab (521). The cover plate (4) is covered on the pressing plate (2) and the positive electrode column and the negative electrode column of the cover plate (4) are respectively connected to the positive electrode bus bar (7) and the negative electrode bus bar (6). The negative electrode bus bar (6) and the positive electrode bus bar (7) are respectively welded to the negative electrode tab (511) and the positive electrode tab (521). The shell (1) is sleeved outside the winding core (5) and one end is sealed and connected to the cover plate (4) and the other end is sealed and connected to the bottom plate (3).

2. The all-solid-state square-shell lithium-ion battery according to claim 1, characterized in that: The pressing plate (2) includes a pressing plate body (21), the upper surface of which is provided with hollow reinforcing ribs (22), and a through hole I (23) for the liquid-conducting fastening core rod (8) to pass through is opened on the pressing plate body (21), and the inner diameter of the through hole I (23) matches the outer diameter of the liquid-conducting fastening core rod (8).

3. The all-solid-state square-shell lithium-ion battery according to claim 1, characterized in that: Two second through holes are provided on the bottom plate (3), and two first through holes are provided on the cover plate (4). One end of the two liquid-conducting fastening core rods (8) is seamlessly connected to the second through holes, and the other end is seamlessly connected to the first through holes.

4. The all-solid-state square-shell lithium-ion battery according to claim 3, characterized in that: The two second through holes are symmetrically distributed on the bottom plate (3), and the two first through holes are symmetrically distributed on the cover plate (4).

5. The all-solid-state square-shell lithium-ion battery according to claim 1, characterized in that: The middle portion of the lower surface of the cover plate (4) is raised, and after both sides of the raised portion are welded to the negative electrode bus bar (6) and the positive electrode bus bar (7), the raised portion is in close contact with the pressing plate (2).

6. The all-solid-state square-shell lithium-ion battery according to claim 1, characterized in that: The winding core (5) comprises a stacked negative electrode sheet (51), a positive electrode sheet (52) and an all-solid electrolyte membrane (53); the positive electrode tab (521) and the negative electrode tab (511) are respectively arranged on one side of the positive electrode sheet (52) and the negative electrode sheet (51); the positive electrode tab (521) and the negative electrode tab (511) are respectively provided with a second long strip hole (522) and a first long strip hole (512) distributed along their respective width directions; the positive electrode tab (521) and the negative electrode tab (511) are respectively located on opposite sides of the winding core (5); the negative electrode bus bar (6) is inserted into a plurality of the first long strip holes (512) and welded to the negative electrode tab (511); and the positive electrode bus bar (7) is inserted into a plurality of the second long strip holes (522) and welded to the positive electrode tab (521).

7. The all-solid-state square-shell lithium-ion battery according to claim 6, characterized in that: The negative electrode sheet (51) includes a negative electrode current collector, which is divided into a negative electrode active material coating area (513) and a foil area. The foil area forms a negative electrode tab (511). Two vias III (514) are provided on the negative electrode active material coating area (513). The negative electrode tab (511) is 10-200 mm long and 5-50 mm wide. The first long strip hole (512) is 5-100 mm long and 1-10 mm wide. The negative electrode active material coating area (513) is 10-600 mm long, 10-200 mm wide and 10-400 μm thick. The diameter of the via III (514) is 5-20 mm. The positive electrode plate (52) and the negative electrode plate (51) have the same structure, and the all-solid electrolyte membrane (53) and the negative electrode active material coating area (513) have the same structure.

8. The all-solid-state square-shell lithium-ion battery according to claim 6, characterized in that: The negative electrode busbar (6) and the positive electrode busbar (7) are both T-shaped structures, and the T-shaped structure includes a horizontal section and a vertical section. The vertical section of the negative electrode busbar (6) is inserted into the first long strip hole (512) and welded to the negative electrode tab (511) lying thereon, and the vertical section of the positive electrode busbar (7) is inserted into the second long strip hole (522) and welded to the positive electrode tab (521) lying thereon. The horizontal section of the negative electrode busbar (6) and the horizontal section of the positive electrode busbar (7) are both welded to the cover plate (4).

9. The all-solid-state square-shell lithium-ion battery according to claim 8, characterized in that: The horizontal section is 2-50 mm higher than the upper surface of the winding core (5) and is higher than the upper surface of the pressing plate (2).

10. The all-solid-state square-shell lithium-ion battery according to any one of claims 1 to 9, characterized in that: The length, height and thickness of the all-solid-state square-shell lithium-ion battery are L1, H1 and T1, respectively, 10mm≤L1≤2000mm, 10mm≤H1≤200mm, and 10mm≤T1≤200mm.

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