Lithium battery assembly and lithium battery packaging shell

Abstract

The invention belongs to the technical field of lithium batteries, and particularly relates to a lithium battery assembly and a lithium battery packaging shell, the lithium battery assembly and the lithium battery packaging shell comprise at least one battery unit and a module shell, and the module shell comprises a shell body. The shell is provided with an internal space for accommodating the at least one battery unit and an open end positioned on the upper side; the top plate covers the upper side of the shell, the open end of the shell is provided with an upwards-protruding installation protrusion, the top plate is provided with an installation hole in press fit with the installation protrusion, and the open end of the shell is welded to the contact part of the top plate. The present invention is advantageous in that the top plate is stably seated on the open end of the case constituting the module case, and the entire periphery of the portion where the open end of the case and the edge of the top plate are in contact with each other is welded, thereby ensuring airtightness even during internal ignition of the battery module.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithium batteries, and in particular relates to a lithium battery assembly and a lithium battery packaging shell. Background Art

[0002] When multiple battery modules are densely present, when thermal runaway occurs in the battery cells of any one battery module and the thermal runaway intensifies, the battery cells may eject high-temperature gas and sparks. Here, sparks refer to active materials or molten aluminum particles that are detached from the electrodes inside the battery cells. At this time, in some cases, flames, etc. may appear in the battery cells. When gas or flames are indiscriminately discharged to the outside of the battery module, thermal damage may be caused to the surrounding battery modules, so the fire may spread rapidly. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the present invention provides a lithium battery assembly and a lithium battery packaging shell to solve the problem that when gas or flame is indiscriminately discharged to the outside of the battery module, it may cause thermal damage to the surrounding battery modules.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] A lithium battery assembly and a lithium battery packaging shell, comprising at least one battery cell and a module shell, wherein the module shell comprises a shell having an internal space for accommodating the at least one battery cell and an open end located at the upper side;

[0006] and a top plate covering the upper side of the shell, wherein the open end of the shell has a mounting protrusion protruding upward, and the top plate has a mounting hole press-fitted with the mounting protrusion, and wherein the open end of the shell is welded to the contact portion of the top plate.

[0007] Furthermore, the shell also includes a bottom plate forming a bottom surface and wall panels forming a front wall, a rear wall, a left wall and a right wall, wherein the open end of the shell forms an upper end of the wall panel.

[0008] Furthermore, the open end of the shell is a flange of the wall panel protruding horizontally outward.

[0009] Furthermore, the module housing is formed of a composite metal in which different kinds of metals are bonded to each other;

[0010] The housing includes an outer portion, the outer portion forming an outer surface of the housing and made of a first metal;

[0011] and an inner portion forming an inner surface of the shell and made of a second metal having a higher melting point than the first metal, wherein an open end of the shell is disposed at an upper edge of the outer portion.

[0012] Further, the top plate includes a first cover portion and a second cover portion, wherein the first cover portion forming the outer surface of the top plate is made of a first metal, and the second cover portion forming the inner surface of the top plate is made of a second metal;

[0013] The first cover portion is located at an upper edge of the outer portion, and the second cover portion is located at an upper edge of the inner portion.

[0014] Furthermore, the first metal is lightweight aluminum, and the second metal is stainless steel.

[0015] The lithium battery packaging shell includes a lithium battery assembly, wherein the assembly guide hole is arranged on the edges of the first cover part and the second cover part.

[0016] Furthermore, the assembly guide hole does not penetrate the first cover portion.

[0017] Furthermore, the outer portion extends above the inner portion.

[0018] Furthermore, the top plate includes a first cover portion and a second cover portion.

[0019] Further, the first cover portion forms the outer surface of the top plate, the second cover portion forms the inner surface of the top plate, and the first cover portion is located on the upper edge of the outer side of the shell, and the second cover portion is located on the upper edge of the inner side of the shell top plate.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The lithium battery packaging shell has high safety performance. When abnormal situations such as short circuit or overcharging occur, the shell can withstand a certain pressure without breaking, thereby protecting the internal battery cells from damage. The open end of the packaging shell is arranged at the upper edge of the outer side, and is press-fitted and welded to the top plate through the upwardly protruding mounting protrusion. This structural design enhances the stability and sealing of the shell, helps to prevent electrolyte leakage and other safety problems. The top plate is stably seated on the open end of the shell constituting the module shell, and the entire periphery of the part where the open end of the shell contacts the edge of the top plate is welded, so that airtightness can be ensured even during internal ignition of the battery module. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a three-dimensional structural schematic diagram of an embodiment of a lithium battery assembly, a lithium battery assembly and a lithium battery packaging shell of the present invention;

[0023] Figure 2 It is a schematic diagram of the exploded structure of an embodiment of a lithium battery assembly, a lithium battery assembly and a lithium battery packaging shell of the present invention;

[0024] Figure 3 The partial structure of the lithium battery assembly and the lithium battery assembly and the lithium battery packaging shell of the present invention is shown in FIG. Figure 1 ;

[0025] Figure 4 The three-dimensional structure of the lithium battery assembly, the lithium battery assembly and the lithium battery packaging shell of the present invention is shown in FIG. Figure 2 ;

[0026] Figure 5 The three-dimensional structure of the lithium battery assembly, the lithium battery assembly and the lithium battery packaging shell of the present invention is shown in FIG. Figure 3 ;

[0027] Figure 6 The three-dimensional structure of the lithium battery assembly, the lithium battery assembly and the lithium battery packaging shell of the present invention is shown in FIG. Figure 4 ;

[0028] Figure 7 The three-dimensional structure of the lithium battery assembly, the lithium battery assembly and the lithium battery packaging shell of the present invention is shown in FIG. Figure 5 ;

[0029] The reference numerals in the drawings of the specification include:

[0030] Battery module 10, battery cell 100, module shell 200, shell body 210, bottom plate 211, wall plate 212, outer portion 213, inner portion 214, opening end 212a, guide protrusion 212b, top plate 220, mounting hole 220a, first cover portion 221, second cover portion 223, positive terminal 310, negative terminal 320. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments:

[0032] It should be noted that the same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0033] In addition, the descriptions of "first", "second", etc. in the present invention are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0034] In the description of the present invention, unless otherwise clearly specified and limited, if the term "connection" or the like appears to indicate the connection relationship between components, the term should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two components or the interaction relationship between two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0035] Example

[0036] like Figure 1-Figure 7 As shown, the battery module 10 includes a plurality of battery cells 100 and a module shell 200, which is composed of a shell body 210 and a top plate 220, wherein the shell body 210 has an internal space capable of accommodating a plurality of battery cells 100 and has an open end 212a on the upper side, and the top plate 220 is connected to the upper portion of the shell body 210 so that the internal space is sealed.

[0037] The battery cell 100 has a thin plate-shaped body and may be a sheet-shaped secondary battery.

[0038] The sheet-shaped secondary battery includes a bag shell, an electrode assembly, and an electrolyte arranged to be contained in the bag shell. For example, the sheet shell may be composed of two bags, at least one of which may have a concave internal space formed therein. In addition, the electrode assembly may be contained in the internal space of the bag. Since the peripheries of the two bags are fused to each other, the internal space containing the electrode assembly may be sealed. The electrode lead may be attached to the electrode assembly, and the electrode lead may be used as an electrode terminal of the sheet-shaped secondary battery by being inserted between the fused portions of the bag shell and exposed to the outside of the bag shell.

[0039] These sheet-shaped secondary batteries may be collectively accommodated in the case 210 in a stack structure in which each of them stands vertically and is stacked in the left-right direction.

[0040] The battery cell 100 does not necessarily have to be composed of a sheet-shaped secondary battery. For example, the battery cell 100 may be composed of a cylindrical secondary battery or a prismatic secondary battery using a metal can as a housing. Various known battery cells 100 may be employed in the battery module 10 of the present disclosure.

[0041] The module case 200 is a structure for accommodating, supporting and protecting the battery cells 100 , and is composed of a case 210 and a top plate 220 .

[0042] The battery module 10 has a structure that blocks all sides of the shell 210 except the upper part, and is configured to cover the upper part of the shell 210 with the top plate 220. By completely welding the opening end 212a of the shell 210 and the part of the top plate 220 that are in contact with each other along the circumferential direction, the airtightness is not easily destroyed even during ignition of the battery cell 100.

[0043] The positive terminal 310 and the negative terminal 320 of the battery module 10 can be set to pass through a wall of the shell 210. As shown in the figure, in order to ensure the insulation between the positive terminal 310 and the negative terminal 320 and the shell body 210, the parts of the positive terminal 310 and the negative terminal 320 that pass through the shell body 210 can be insulated with materials such as mica that have excellent fire resistance and insulation properties.

[0044] An exhaust port (not shown) may be provided on at least one side of the housing 210 to intentionally exhaust gas from the module housing 200 through a specific path when the battery cell 100 is ignited. For example, the exhaust port has a structure in which an explosion-proof membrane is applied to a hole, and is configured so that the explosion-proof membrane is usually blocked, but when the internal pressure of the module housing 200 rises above a certain pressure, the explosion-proof membrane may be destroyed and opened. In addition, by connecting an air pipe (not shown) to the exhaust port outside the battery module 10, when an accident occurs, high-temperature gas can move along the air pipe through a specific path.

[0045] The main components of the module housing 200 - the housing 210 and the top plate 220 - are assembled and welded.

[0046] The housing 210 includes a bottom plate 211 forming a bottom surface supporting the lower part of the battery cell 100 stack and a wall plate 212 forming a wall surface covering the front, rear, left and right sides of the battery cell 100 stack. The upper side of the housing 210 is open, and the rest of the housing 210 except the upper side can be provided in the form of a sealed box. Therefore, the opening end 212a of the housing 210 is set on the upper edge of the wall plate 212.

[0047] The open end 212a of the housing 210 is configured to be in the shape of a flange that protrudes horizontally outward from the other parts of the wall plate 212. That is, the open end 212a of the housing 210 is configured to protrude over the entire circumference of the upper end of the wall plate 212. Therefore, the housing 210 has the open end 212a that has a sufficiently wide contact interface with the top plate 220, so that a high degree of freedom is provided in designing the size and position of the mounting protrusion 212b described later.

[0048] The open end 212a of the housing 210 has an assembly guide protrusion 212b protruding upward from the surface thereof, which can serve as a means for fixedly placing the top plate 220 on the open end 212a of the housing 210 and preventing movement during subsequent welding.

[0049] A plurality of mounting protrusions 212 b may be provided, and the plurality of mounting protrusions 212 b may be equally spaced on the left and right long sides of the opening end 212 a of the housing 210 and be provided in a cylindrical shape.

[0050] The present device is not limited to the position and shape of the mounting protrusion 212b. The mounting protrusion 212b can be configured differently from the present embodiment. For example, the mounting protrusion 212b can be located at regular intervals around the entire circumference of the open end 212a of the housing 210 including the long side line and the short side line, and can be set to various shapes, such as a polygonal column, a hemispherical shape, etc.

[0051] The mounting protrusion 212 b may function as a stopper to prevent incorrect assembly of the housing 210 and the top plate 220 and to prevent the top plate 220 from moving up, down, left, and right.

[0052] The top plate 220 is a cover structure for sealing the inner space of the housing 210 , and may be disposed to be accurately aligned with the open end 212 a of the housing 210 based on the mounting protrusion 212 b .

[0053] The edge of the top plate 220 has a mounting hole 220 a . When the top plate 220 is assembled to the housing 210 , the mounting hole 220 a is pressed against the mounting protrusion 212 b in a vertical direction, so that the edge of the top plate 220 is accurately aligned with the open end 212 a of the housing 210 .

[0054] In other words, the top plate 220 is provided with the same number of assembly guide holes 220a as the number of assembly guide protrusions 212b, and the assembly guide holes 220a are arranged at various positions at the edge of the top plate 220 in a vertical correspondence with the assembly guide protrusions 212b. Therefore, as shown in FIG. Figure 4 Therefore, when the top plate 220 is placed on the open end 212 a of the housing 210 by aligning the respective mounting holes 220 a with the respective mounting protrusions 212 b , the housing 210 and the top plate 220 may be accurately aligned.

[0055] In addition, since each mounting protrusion 212 b and each mounting hole 220 a are press-fitted with each other in the vertical direction, the position of the housing 210 and the top plate 220 will not be misaligned during the subsequent welding work.

[0056] As described above, when the top plate 220 is accurately placed on the open end 212a of the shell 210, the entire outer circumference of the portion where the open end 212a of the shell 210 and the edge of the top plate 220 contact each other is seamlessly welded, and the module shell 200 of the battery module 10 according to the present disclosure has a weld bead WB line extending along the entire circumference without being cut off.

[0057] Therefore, even if the battery module 10 catches fire, the airtight structure between the housing 210 and the top plate 220 is not easily destroyed, so that high-temperature gas or flames are not discharged to the outside from between the opening end 212 a of the housing 210 and the edge of the top plate 220 .

[0058] Meanwhile, the module case 200 according to an embodiment of the present disclosure is made of a lightweight composite metal in which different kinds of metals are combined with each other to have high heat resistance while being lightweight, and may be formed of different inner and outer materials.

[0059] The outer portion 213 forms the outer surface of the shell 210 and is made of a first metal; the inner portion 214 forms the inner surface of the shell 210 and is made of a second metal having a higher melting point than the first metal.

[0060] In this embodiment, the first metal may be lightweight aluminum (Al), and the second metal may be stainless steel. The melting point of aluminum is about 660°, and the melting point of stainless steel is about 2750°. That is, in the housing 210 of this embodiment, the outer portion 213 is made of aluminum, and the inner portion 214 is made of stainless steel having a higher heat resistance than aluminum. Of course, at least one of the first metal and the second metal may be replaced by a metal having a higher heat resistance than that of this embodiment.

[0061] Since the box body 210 is made of composite metal as described above, the bottom plate 211 and the wall plate 212 have a double-layer structure as shown in the figure. Figure 6In addition, the box body 210 of this embodiment has a step difference between the upper edge of the outer portion 213 and the upper edge of the inner portion 214 constituting the wall panel 212, that is, the upper end of the outer portion 213 is set higher than the upper end of the inner portion 214, and the upper edge of the outer portion 213 serves as the opening end 212a of the box body 210.

[0062] The top plate 220 includes a first cover portion 221 and a second cover portion 223 forming a double layer.

[0063] The first cover 221 forms the outer surface of the top plate 220 and is made of a first metal. The second cover 223 forms the inner surface of the top plate 220 and is made of a second metal. That is, in the top plate 220 according to the present embodiment, the first cover 221 is made of aluminum, and the second cover 223 is made of stainless steel.

[0064] The edge of the first cover portion 221 defines a mounting hole 220 a . The edge of the first cover portion 221 is located at the upper edge of the outer portion 213 of the housing 210 . The edge of the second cover portion 223 is located at the upper edge of the inner portion 214 of the housing 210 .

[0065] According to the configuration of the module housing 200, all inner walls of the module housing 200 surrounding its inner space are made of stainless steel having high heat resistance. Therefore, when the battery module 10 is ignited therein, the module housing 200 can withstand even high temperatures without deformation, thus maintaining airtightness.

[0066] Since the top plate 220 can be stably seated on the open end 212a of the shell 210, and the entire circumference of the portion where the open end 212a of the shell 210 and the edge of the top plate 220 contact each other can be welded, when the battery module 10 is ignited in the module shell 200, gas or flame is not indiscriminately discharged to the outside of the module shell 200.

[0067] Furthermore, the module case 200 is made of a composite metal, but the inner surface of the module case 200 is formed of a metal having relatively better heat resistance than aluminum, thereby providing a battery module 10 having better mechanical rigidity and higher heat resistance than the related art.

[0068] Meanwhile, the battery pack (not shown) according to the present disclosure includes one or more battery modules described above. In addition to the battery module, the battery pack may also include a pack housing (not shown) for accommodating the battery module, various devices (not shown) for controlling the charge / discharge of the battery module, such as a battery management system (BMS), a current sensor, a fuse, etc.

[0069] The above is only an embodiment of the present invention. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field are aware of all the common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement the scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for the ordinary technicians in the relevant field to implement this application. It should be pointed out that for the technicians in this field, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A lithium battery assembly, comprising at least one battery cell (100) and a module housing (200), characterized in that: The module housing (200) comprises a housing (210) having an inner space for accommodating the at least one battery cell (100) and an open end (212a) located at an upper side; and a top plate (220), wherein the top plate (220) covers the upper side of the shell (210), wherein the open end (212a) of the shell (210) has a mounting protrusion (212b) protruding upward, and the top plate (220) has a mounting hole (220a) press-fitted with the mounting protrusion (212b), and wherein the open end (212a) of the shell and the contact portion of the top plate (220) are welded.

2. The lithium battery assembly according to claim 1, characterized in that: The shell (210) further comprises a bottom plate forming a bottom surface and a wall plate (212) forming a front wall, a rear wall, a left wall and a right wall, wherein the open end (212a) of the shell (210) forms an upper end of the wall plate.

3. The lithium battery assembly according to claim 2, characterized in that: The open end (212a) of the shell (210) is a flange of the wall plate (212) protruding horizontally outward.

4. The lithium battery assembly according to claim 3, characterized in that: The module housing (210) is formed of a composite metal in which different types of metals are bonded to each other; The housing (210) comprises an outer portion (213), wherein the outer portion (213) forms an outer surface of the housing and is made of a first metal; and an inner portion (214), the inner portion (214) forming the inner surface of the shell (210) and being made of a second metal having a melting point higher than that of the first metal, wherein the open end (212a) of the shell (210) is arranged at the upper edge of the outer portion (213).

5. The lithium battery assembly according to claim 4, characterized in that: The top plate (220) comprises a first cover portion (221) and a second cover portion (223), wherein the first cover portion (221) forming the outer surface of the top plate (220) is made of a first metal, and the second cover portion (223) forming the inner surface of the top plate is made of a second metal; The first cover portion (221) is located at an upper edge of the outer portion (213), and the second cover portion is located at an upper edge of the inner portion (214).

6. The lithium battery assembly according to claim 5, characterized in that: The first metal is lightweight aluminum, and the second metal is stainless steel.

7. A lithium battery packaging shell, comprising a lithium battery assembly according to any one of claims 1 to 6, characterized in that: The assembly guide hole (220a) is arranged on the edges of the first cover part (221) and the second cover part (223).

8. The lithium battery assembly and lithium battery packaging shell according to claim 7, characterized in that: The assembly guide hole (220a) does not penetrate the first cover portion (221).

9. The lithium battery packaging shell according to claim 8, characterized in that: The outer portion (213) extends above the inner portion (214).

10. The lithium battery packaging shell according to claim 9, characterized in that: in, The top plate (220) includes a first cover portion (221) and a second cover portion (223), wherein the first cover portion (221) forms the outer surface of the top plate (220), and the second cover portion (223) forms the inner surface of the top plate (220), and the first cover portion (221) is located on the upper edge of the outer side portion (213) of the shell, and the second cover portion (223) is located on the upper edge of the inner side portion (214) of the shell top plate (220).

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