Battery case and battery

Abstract

The present application discloses a battery shell and a battery, wherein the shell is used to assemble a plurality of cylindrical winding cores, the shell comprises an outer shell and a plurality of lattice support plates arranged inside the outer shell, the outer shell comprises a bottom wall and a plurality of side walls arranged around the bottom wall, each of the lattice support plates is formed into at least two folding plates by bending, and the plurality of lattice support plates are sequentially arranged in the outer shell at intervals according to preset positions, the bending protrusions and bending recesses between adjacent lattice support plates are opposite, and the four folding plates connected to each pair of relatively far bending protrusions and bending recesses of adjacent lattice support plates define a winding core lattice, and the four folding plates of the winding core lattice are respectively configured to radially limit the outer circumferential surface of the cylindrical winding core. The present application is conducive to saving space and further improving the energy density of the battery.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery housing and a battery. Background Art

[0002] At present, lithium-ion / sodium-ion cylindrical batteries have gradually become mainstream products in the new energy industry due to their high energy density, good capacity consistency, and ability to support high-rate charge and discharge. More and more manufacturers continue to pursue compactness optimization of cylindrical battery structures to increase energy density and adopt various methods such as rehydration to improve battery cycle performance. However, current cylindrical power batteries have the following common problems:

[0003] After cylindrical power batteries are assembled into modules, the space / gap between batteries cannot be fully utilized, resulting in a bottleneck in further improving battery energy density;

[0004] To ensure the strength of single cylindrical power batteries, they are generally provided with thicker shells, which results in a certain amount of space waste in battery assembly;

[0005] The internal space of a single cylindrical power battery is limited, resulting in a limited amount of electrolyte injection. In the later stages of the battery cycle, the electrolyte is depleted, causing the battery cycle life to plummet. It is also very difficult to disassemble the battery pack for secondary refilling. Summary of the invention

[0006] The purpose of the present application is to provide a battery housing and a battery, which can solve at least one technical problem in the background technology.

[0007] In order to achieve the above-mentioned purpose, the present application provides a battery shell for assembling multiple cylindrical winding cores, the shell includes an outer shell and multiple lattice support plates arranged inside the outer shell, the outer shell includes a bottom wall and multiple side walls arranged around the bottom wall, each of the lattice support plates is formed by bending to form at least two folding plates, and the multiple lattice support plates are arranged in sequence in the outer shell at preset positions, the bending protrusions and bending recesses between adjacent lattice support plates are opposite, and the four folding plates connected to each pair of relatively far-away bending protrusions and bending recesses of adjacent lattice support plates define a winding core lattice, and the four folding plates of the winding core lattice are respectively configured to radially limit the outer circumferential surface of the cylindrical winding core.

[0008] Optionally, two ends of the lattice support plate are respectively fixedly connected to different side walls of the shell.

[0009] Optionally, electrolyte is injected into the space outside the cylindrical winding core inside the shell.

[0010] Optionally, a plurality of hollow holes are provided on the lattice support plate, and the hollow holes are used to allow the electrolyte injected into the shell to flow freely.

[0011] Optionally, a notch penetrating downward is provided at the bottom of the lattice support plate, and the notch is used to allow the electrolyte injected into the shell to flow freely.

[0012] Optionally, an upper edge of each of the lattice support plates is lower than an upper edge of a side wall of the housing to provide an insulating layer.

[0013] Optionally, the lattice support plate has thermal conductivity.

[0014] Optionally, annular grooves are formed on the outer side of the bottom wall of the shell at positions corresponding to each of the core lattices, and annular convex portions are formed on the inner side of the bottom wall of the shell corresponding to each of the annular grooves, and the annular convex portions are used for welding to the collecting plate at the bottom of the cylindrical core.

[0015] Optionally, a liquid injection hole is provided on the bottom wall of the shell at a position corresponding to at least a portion of the core through hole of the cylindrical core.

[0016] Optionally, the thickness of the lattice support plate is smaller than the thickness of the side wall of the housing.

[0017] Optionally, the thickness of the lattice support plate is 1 / 3 to 1 / 2 of the thickness of the side wall of the shell.

[0018] Optionally, the lattice support plate has a thickness of 0.15 mm to 0.25 mm.

[0019] In order to achieve the above-mentioned purpose, the present application provides a battery, such as the shell mentioned above, wherein a cylindrical core is placed in each core lattice of the shell.

[0020] Optionally, the battery further comprises a cover body covering the open end of the housing;

[0021] The battery is respectively provided with a pole, a positive current collector and a negative current collector corresponding to each of the cylindrical winding cores. The pole is fixedly arranged on the cover body and corresponds to the winding core through hole of the cylindrical winding core. The positive current collector is welded on the cylindrical winding core and welded to the pole, and the negative current collector is welded between the cylindrical winding core and the bottom wall of the outer shell.

[0022] The battery shell of the present application includes an outer shell and a plurality of lattice support plates arranged inside the outer shell, each lattice support plate is formed into at least two folding plates by bending, and the plurality of lattice support plates are arranged in sequence in the outer shell at preset positions, and the bending protrusions and bending recesses between adjacent lattice support plates are opposite, and the four folding plates connected to each pair of relatively far-away bending protrusions and bending recesses of adjacent lattice support plates define a core lattice, and the four folding plates of the core lattice are respectively configured to radially limit the outer circumferential surface of the cylindrical core at different positions in the circumferential direction. The present application uses the plurality of lattice support plates inside the outer shell to define a plurality of core lattices to directly limit each cylindrical core, so as to realize reliable assembly of a plurality of cylindrical cores in one outer shell, without the need to specially set a sleeve shell for a single cylindrical core to form a single cylindrical battery, and then only needs to ensure that the outer shell has greater strength, and the thickness of the internal lattice support plate can be set relatively thin, which is relatively conducive to saving space and further improving the energy density of the battery compared to configuring a thicker sleeve shell for each cylindrical core separately. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the three-dimensional structure of the battery housing of an embodiment of the present application.

[0024] Figure 2 yes Figure 1 Schematic diagram of the three-dimensional structure of the battery housing from another perspective.

[0025] Figure 3 yes Figure 1 Schematic diagram of the three-dimensional structure of a lattice support plate.

[0026] Figure 4 yes Figure 1 Schematic diagram of the three-dimensional structure of the middle shell.

[0027] Figure 5 yes Figure 1 Schematic diagram of an insulating layer disposed on a mid-lattice support plate.

[0028] Figure 6 It is a schematic diagram of a three-dimensional structure in which a winding core is assembled in a battery shell according to an embodiment of the present application, wherein current collecting plates are provided at both ends of the winding core.

[0029] Figure 7 yes Figure 6 Schematic diagram of the top view structure.

[0030] Figure 8 It is a schematic diagram of the cross-sectional structure of the battery of the embodiment of the present application.

[0031] Fig. 9 It is a schematic diagram of the three-dimensional structure of a winding core welded with a collecting disk according to an embodiment of the present application. DETAILED DESCRIPTION

[0032] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0033] See also Figures 1 to 9 The embodiment of the present application discloses a battery shell for assembling multiple cylindrical cores 3, the shell includes an outer shell 1 and multiple lattice support plates 2 arranged inside the outer shell 1, the outer shell 1 includes a bottom wall 11 and multiple side walls 12 arranged around the bottom wall 11, each lattice support plate 2 is formed by bending to form at least two folding plates 21, and multiple lattice support plates 2 are arranged in sequence in the outer shell 1 at preset positions, and the bending protrusions 22 and bending recesses 23 between adjacent lattice support plates 2 are opposite, and the four folding plates 21 connected to each pair of relatively far-away bending protrusions 22 and bending recesses 23 of adjacent lattice support plates 2 define a core lattice H, and the four folding plates 21 of the core lattice H are respectively configured to radially limit the outer circumferential surface of the cylindrical core 3.

[0034] It is understandable that, in the present application, except for the lattice support plate 2 having only two folding plates 21 including only one bending convex portion 22 or bending concave portion 23, in other cases, the bending convex portions 22 and the bending concave portions 23 of the lattice support plate 2 appear alternately to form a wave-like structure. In the present application, the bending convex portion 22 and the bending concave portion 23 are relative, and from another perspective, the two can be defined in reverse.

[0035] The bending convex portions 22 and the bending concave portions 23 between adjacent lattice support plates 2 are opposite, which means that the bending convex portion 22 of one is opposite to the bending concave portion 23 of the other, and the bending concave portion 23 of one is opposite to the bending convex portion 22 of the other. Of course, when the number of bends of the two is not corresponding, there will be unpaired bending convex portions 22 / bending concave portions 23.

[0036] Since the bending protrusions 22 and bending recesses 23 between adjacent lattice support plates 2 are opposite, the distance between the bending pairs (a group of opposite bending protrusions 22 and bending recesses 23 constitutes a bending pair) between two lattice support plates 2 will alternate between being relatively far away and relatively close, and the four folded plates 21 connecting each pair of relatively far bending protrusions 22 and bending recesses 23 of adjacent lattice support plates 2 will define a core lattice H.

[0037] The present application utilizes multiple lattice support plates 2 inside the outer shell 1 to define multiple core lattices H to directly limit each cylindrical core 3, so that one outer shell 1 can reliably assemble multiple cylindrical cores 3. There is no need to specially set up a sleeve shell for a single cylindrical core 3 to form a single cylindrical battery. Therefore, it is only necessary to ensure that the outer shell 1 has a large strength. The thickness of the internal lattice support plate 2 can be set relatively thin. Compared with separately configuring a thicker sleeve shell for each cylindrical core 3, it is beneficial to save space and further improve the battery energy density.

[0038] In order to ensure the strength of the shell 1, the side wall 12 and the bottom wall 11 of the shell 1 are generally set to have a certain thickness, while the lattice support plate 2 is set inside the shell 1, so the strength requirement is not so high, and the thickness of the lattice support plate 2 can be set to be significantly thinner than the thickness of the side wall 12 of the shell 1. In addition, since part of the folding plate 21 can be shared by different core lattices H, it is conducive to saving space.

[0039] Specifically, the thickness of the lattice support plate 2 is 1 / 3-1 / 2 of the thickness of the side wall 12 of the housing 1 .

[0040] Specifically, the thickness of the lattice support plate 2 can be set to 1 / 3-1 / 2 of the thickness of the side wall of the sleeve shell of the cylindrical winding core 3 .

[0041] Specifically, the thickness of the lattice support plate 2 is 0.15 mm to 0.25 mm, while the thickness of the side wall of the sleeve shell of the cylindrical winding core 3 is generally 0.3 mm to 0.4 mm. The thickness of the lattice support plate 2 is significantly smaller than the thickness of the sleeve shell, which is conducive to saving space.

[0042] Specifically, the angle between adjacent folded plates 21 of the lattice support plate 2 is between 120° and 135°.

[0043] In some embodiments, both ends of the lattice support plate 2 are respectively fixedly connected to different side walls 12 of the housing 1. By respectively fixing both ends of the lattice support plate 2 to different side walls 12 of the housing 1, the lattice support plate 2 can be stably positioned in the housing 1, thereby facilitating the reliable positioning of the cylindrical winding core 3 in the winding core lattice H. In addition, under normal circumstances, the lattice support plate 2 is placed on the bottom wall 11 of the housing 1.

[0044] Specifically, the two ends of the lattice support plate 2 can be fixedly connected to different side walls 12 of the shell 1 by welding, or by setting grooves for fixing, or by using both methods at the same time, etc., which is not limited in the present application.

[0045] In the specific example shown in the accompanying drawings, the housing 1 includes three side walls 12 connected end to end, forming a roughly equilateral triangle that is smoothly connected at a corner. The number of lattice support plates 2 is four, of which the number of lattice support plates 2 including two folding plates 21 is one, the number of lattice support plates 2 including four folding plates 21 is one, and the number of lattice support plates 2 including six folding plates 21 is two. A lattice support plate 2 with two folding plates 21, a lattice support plate 2 with four folding plates 21, and two lattice support plates 2 with six folding plates 21 are sequentially arranged on the side wall 12 facing the corner from one corner of the housing 1. It can be understood that in order to ensure the reliability of the structure and the utilization of the space, the three bent concave portions 23 of the lattice support plate 2 of the six folding plates 21 on the outside are in contact with the corresponding side walls 12 of the housing 1. In addition, the bent convex portions 22 of the lattice support plate 2 of the two folding plates 21 are in contact with the inner side of the corresponding corner.

[0046] Of course, in the present application, the outer shell 1 is not limited to the above-mentioned form, and it can have various shapes. Accordingly, the number of lattice support plates 2 and the number of folding plates 21 included are not limited, as long as the lattice support plates 2 arranged in the outer shell 1 can define a plurality of closely arranged core lattices H.

[0047] In order to solve the problem that the internal space of a single cylindrical battery is limited, resulting in a limited amount of electrolyte injection, and the electrolyte is exhausted in the later stage of the battery cycle, resulting in a drop in the battery cycle life, and it is also very difficult to disassemble the battery pack for secondary replenishment, in addition to injecting electrolyte into the cylindrical core 3, the embodiment of the present application can inject electrolyte into the space outside the cylindrical core 3 inside the shell, while solving the above-mentioned problem and making full use of the internal space of the shell.

[0048] In some embodiments, a plurality of hollow holes 24 are provided on the lattice support plate 2, and the hollow holes 24 are used to allow the electrolyte injected into the shell to flow freely, so that the electrolyte in the inner space of the shell can maintain a substantially constant liquid level.

[0049] Specifically, a plurality of hollow holes 24 are provided at the bottom of each folded plate 21 of the lattice support plate 2 .

[0050] In a specific example, each folded plate 21 of each lattice support plate 2 is provided with at least one row of hollow holes 24 arranged along the up-down direction.

[0051] In a specific example, the hollow holes 24 are circular micro-holes, but the hollow holes 24 are not limited to a specific form.

[0052] In some embodiments, a notch 25 is provided at the bottom of the lattice support plate 2, and the notch 25 is used to allow the electrolyte injected into the shell to flow freely. By providing a notch 25 that penetrates downward at the bottom of the lattice support plate 2, when there is little electrolyte in the shell, the flow of the notch 25 can also be used to keep the liquid level basically consistent.

[0053] Specifically, a notch 25 penetrating downwards is provided at the bottom of each folded plate 21 of the lattice support plate 2 .

[0054] In some embodiments, the lattice support plate 2 is made of stainless acid-resistant steel, but it is not limited thereto.

[0055] In some embodiments, the upper edge of each lattice support plate 2 is lower than the upper edge of the side wall 12 of the housing 1 to provide an insulating layer 4. Specifically, the distance from the upper edge of the lattice support plate 2 to the upper edge of the side wall 12 of the housing 1 is between 5 mm and 10 mm, and the insulating layer 4 is provided throughout.

[0056] Specifically, the insulating layer 4 can be insulating glue, AT9, or formed by PP injection molding, etc., and is not specifically limited.

[0057] In order to facilitate the heat dissipation of the cylindrical core 3, the lattice support plate 2 has thermal conductivity, and a material with excellent heat dissipation performance can be selected.

[0058] In some embodiments, an annular groove 111 is formed on the outer side of the bottom wall 11 of the housing 1 at the position corresponding to each core lattice H, and an annular convex portion 112 is formed on the inner side of the bottom wall 11 of the housing 1 corresponding to each annular groove 111. The annular convex portion 112 is used to weld with the current collecting plate 5 at the bottom of the cylindrical core 3. When the annular convex portion 112 and the current collecting plate 5 at the bottom of the cylindrical core 3 are welded, the annular groove 111 is provided to facilitate welding. Specifically, the annular convex portion 112 and the current collecting plate 5 at the bottom of the cylindrical core 3 are welded by laser penetration welding.

[0059] In some embodiments, the bottom wall 11 of the housing 1 is provided with a liquid injection hole 113 at a position corresponding to at least a portion of the winding core through hole 31 of the cylindrical winding core 3 , so that the battery can be injected with liquid through the liquid injection hole 113 .

[0060] Please combine Figures 1 to 9 The present application also discloses a battery, comprising a shell as described above, wherein a cylindrical winding core 3 is placed in each winding core lattice H of the shell.

[0061] The present application utilizes multiple lattice support plates 2 inside the outer shell 1 to define multiple core lattices H to directly limit each cylindrical core 3, so that one outer shell 1 can reliably assemble multiple cylindrical cores 3. There is no need to specially set up a sleeve shell for a single cylindrical core 3 to form a single cylindrical battery. Therefore, it is only necessary to ensure that the outer shell 1 has a large strength. The thickness of the internal lattice support plate 2 can be set relatively thin. Compared with separately configuring a thicker sleeve shell for each cylindrical core 3, it is beneficial to save space and further improve the battery energy density.

[0062] In some embodiments, the battery further includes a cover 6 covering the open end of the housing 1, that is, an end of each side wall 12 away from the bottom wall 11. The cover 6 can be sealed and fixed to the housing 1 by laser seam welding.

[0063] Specifically, each cylindrical core 3 of the battery is respectively provided with a pole 7, a positive current collector 8 and a negative current collector 5. The pole 7 is fixedly arranged on the cover body 6 and corresponds to the core through hole 31 of the cylindrical core 3. The positive current collector 8 is welded on the cylindrical core 3 and welded to the pole 7. The negative current collector 5 is welded between the cylindrical core 3 and the bottom wall 11 of the outer shell 1.

[0064] To facilitate understanding of the present application, the assembly process of the battery in a specific example is briefly described below, but this should not be used to limit the present application.

[0065] First, each lattice support plate 2 is assembled into the housing 1 , wherein both ends of the lattice support plate 2 are fixed to the two side walls 12 of the housing 1 .

[0066] Next, after the full pole tabs at both ends of the cylindrical winding core 3 have completed pre-treatments such as flattening / patting, the full pole tabs at both ends of the cylindrical winding core 3 are fixed to the positive electrode collector 8 and the negative electrode collector 5 by laser welding.

[0067] Next, each cylindrical winding core 3 after the current collecting plate welding is respectively placed in the winding core lattice H in the shell.

[0068] Next, the cylindrical winding core 3 is supported by a clamp, and the annular protrusion 112 on the inner side of the bottom wall 11 of the shell 1 is fixed to the negative electrode current collecting plate 5 by laser penetration welding through the annular recessed groove 111 on the outer side of the bottom wall 11 of the shell 1 .

[0069] Next, the cover 6 is sealed and fixed to the open end of the housing 1 , wherein the pole 7 has been assembled on the cover 6 in advance.

[0070] Next, the positive electrode current collecting plate 8 and the pole 7 are welded and fixed by torque welding through the liquid injection hole 113 of the bottom wall 11 of the housing 1 and the winding core through hole 31 .

[0071] Next, conventional injection / formation is performed, and the electrolyte will enter the space outside each cylindrical core 3 in the shell. The electrolyte can first enter the core through hole 31 through the injection hole 113, and then flow into the space outside each cylindrical core 3 in the shell and the inside of other cylindrical cores 3 through the end of the cylindrical core 3 away from the injection hole 113.

[0072] Next, a sealing pin is welded at the injection hole 113 to seal and fix it.

[0073] The above disclosure is only a preferred example of the present application, and its role is to facilitate the technical personnel in this field to understand and implement it. Of course, it cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the scope of the patent application of the present application still fall within the scope covered by the present application.

Claims

1. A battery casing for assembling a plurality of cylindrical winding cores, characterized in that: The shell comprises an outer shell and a plurality of lattice support plates arranged inside the outer shell, the outer shell comprises a bottom wall and a plurality of side walls arranged around the bottom wall, each of the lattice support plates is formed into at least two folded plates by bending, and the plurality of lattice support plates are sequentially arranged in the outer shell at preset positions, the bending protrusions and bending concave portions between adjacent lattice support plates are opposite, and the four folded plates connected to each pair of relatively far-away bending protrusions and bending concave portions of adjacent lattice support plates define a winding core lattice, and the four folded plates of the winding core lattice are respectively configured to radially limit the outer circumferential surface of the cylindrical winding core; Two ends of the lattice support plate are respectively fixedly connected to different side walls of the housing; The electrolyte is injected into the space outside the cylindrical winding core inside the shell; The lattice support plate is provided with a plurality of hollow holes, and the hollow holes are used to allow the electrolyte injected into the shell to flow freely; The lattice support plate has thermal conductivity; The thickness of the lattice support plate is set to 1 / 3-1 / 2 of the thickness of the side wall of the sleeve shell of the cylindrical winding core.

2. The battery housing according to claim 1, characterized in that: A notch penetrating downward is provided at the bottom of the lattice support plate, and the notch is used to allow the electrolyte injected into the shell to flow freely.

3. The battery housing according to claim 1, characterized in that: The upper edge of each of the lattice support plates is lower than the upper edge of the side wall of the shell to provide an insulating layer.

4. The battery housing according to claim 1, characterized in that: The outer side of the bottom wall of the shell is formed with annular grooves at positions corresponding to the core lattices, and the inner side of the bottom wall of the shell is formed with annular convex parts corresponding to the annular grooves, and the annular convex parts are used for welding with the collecting plate at the bottom of the cylindrical core.

5. The battery housing according to claim 1, characterized in that: The bottom wall of the shell is provided with a liquid injection hole at a position corresponding to at least a portion of the winding core through hole of the cylindrical winding core.

6. The battery case according to claim 1, characterized in that: The thickness of the lattice support plate is smaller than the thickness of the side wall of the housing.

7. The battery casing according to claim 6, characterized in that: The thickness of the lattice support plate is 1 / 3 to 1 / 2 of the thickness of the side wall of the housing.

8. The battery housing according to claim 6 or 7, characterized in that: The thickness of the lattice support plate is 0.15 mm to 0.25 mm.

9. A battery, characterized in that: It comprises the shell as claimed in any one of claims 1 to 8, wherein a cylindrical winding core is respectively placed in each winding core lattice of the shell.

10. The battery according to claim 9, characterized in that The battery further comprises a cover body covering the open end of the housing; The battery is respectively provided with a pole, a positive current collector and a negative current collector corresponding to each of the cylindrical winding cores. The pole is fixedly arranged on the cover body and corresponds to the winding core through hole of the cylindrical winding core. The positive current collector is welded on the cylindrical winding core and welded to the pole, and the negative current collector is welded between the cylindrical winding core and the bottom wall of the outer shell.

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