Battery cell and battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a battery unit and a battery pack, according to the battery unit provided by the utility model, a shell is a metal shell, so that the shell has conductive capability; the insulating ring is arranged between the openings of the two shells, so that the positive shell is insulated from the negative shell; after the positive pole of the single battery is directly contacted with the inner wall surface of the positive shell, the positive shell is the positive pole of the battery unit, and after the negative pole of the single battery is directly contacted with the inner wall surface of the negative shell, the negative shell is the negative pole of the battery unit. Compared with the mode of continuously welding adjacent anodes in the existing scheme, the battery unit with the structure can be used for supplying power by enabling the anode post and the cathode post of the battery monomer to be in direct contact with the metal shell, so that the phenomenon of thermal runaway caused by low welding quality among part of anodes is avoided; and meanwhile, the production cost is reduced by omitting a welding procedure.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery unit and a battery pack. Background Art

[0002] Cylindrical batteries are widely used due to their good consistency, high production efficiency, and strong heat dissipation capabilities at the system level.

[0003] Cylindrical battery is a type of battery, which is usually packaged in a cylindrical steel shell, and the bare cell is made using a winding process. One end is the positive electrode and the other end is the negative electrode. Due to its small size, its capacity is low. Therefore, in actual processing, in order to achieve capacity expansion, multiple cylindrical batteries are arranged side by side, and the positive electrodes of each cylindrical battery are continuously welded. However, after multiple welding, if the welding quality between any positive electrode and the adjacent positive electrode is poor, it may cause the battery circuit to be blocked, and then cause thermal runaway. Utility Model Content

[0004] In view of this, the utility model provides a battery unit and a battery pack to solve the problem of thermal runaway that is prone to occur due to low welding quality after welding the positive electrodes of each cylindrical battery in the existing solution.

[0005] In the first aspect, the utility model provides a battery unit, including a shell, an insulating ring and a battery cell. Specifically, the shell is a metal shell, and the shell includes a first shell and a second shell, the first shell and the second shell are arranged opposite to each other, and the end of the first shell close to the second shell and the end of the second shell close to the first shell are both provided with openings, and the two openings are connected so that the first shell and the second shell are enclosed to form a closed installation chamber, in the first shell and the second shell, one of the two is a positive pole shell, and the other is a negative pole shell; the insulating ring is installed between the two openings along the height direction, and is used to seal and insulate the first shell and the second shell; there are multiple battery cells, and the multiple battery cells are arranged inside the shell, the positive poles of the multiple battery cells are in contact with the inner wall surface of the positive pole shell, and the negative poles of the multiple battery cells are in contact with the inner wall surface of the negative pole shell.

[0006] Beneficial effects: By making the shell a metal shell, the shell has the ability to conduct electricity; one of the first shell and the second shell is a positive shell, and the other is a negative shell, and an insulating ring is used to be set between the openings of the two shells, so that the positive shell and the negative shell are insulated; after the positive pole of the battery cell is directly in contact with the inner wall surface of the positive shell, the positive shell can be used as the positive pole of the battery unit, and after the negative pole of the battery cell is directly in contact with the inner wall surface of the negative shell, the negative shell can be used as the negative pole of the battery unit. Compared with the existing solution of continuously welding adjacent positive poles, the battery unit of this structure can be used for power supply by making the positive pole and negative pole of the battery cell directly contact the metal shell, avoiding the phenomenon of thermal runaway caused by low welding quality between some positive poles; at the same time, the production cost is reduced by omitting the welding process.

[0007] In an optional embodiment, the inner wall surface of the first shell and the inner wall surface of the second shell are both provided with a fixing portion, and the fixing portion is used to fix the positive electrode post or the negative electrode post.

[0008] Beneficial effect: By providing fixing parts on the inner wall surfaces of the first shell and the second shell, the positive electrode column and the negative electrode column are fixed to avoid misalignment between the positive electrode column and the inner wall surface of the positive shell, or to avoid misalignment between the negative electrode column and the inner wall surface of the negative shell, thereby avoiding circuit failure and making the circuit more reliable and stable when powering on.

[0009] In an optional embodiment, the battery cell also includes a battery body; the positive electrode post and the negative electrode post are respectively arranged at two opposite ends of one pair of the battery body, and the positive electrode post and the negative electrode post are both arranged outside the battery body; the height dimension of any one of the fixing parts is smaller than the height dimension of the positive electrode post or the height dimension of the negative electrode post fixedly connected to the fixing part.

[0010] Beneficial effect: By making the battery cell include a battery body, and arranging the positive electrode post and the negative electrode post outside the battery body, at this time, by making the height dimension of the fixing part smaller than the height dimension of the positive electrode post or the height dimension of the negative electrode post, a gap can be left between any fixing part and the battery body, ensuring that the positive electrode post is in contact with the positive electrode shell, and ensuring that the negative electrode post is in contact with the negative electrode shell.

[0011] In an optional implementation, the shell is made of aluminum, aluminum alloy or stainless steel.

[0012] In an optional embodiment, the shell is a square shell.

[0013] In an optional implementation, the height H of the insulating ring is ≥5 mm.

[0014] In a second aspect, the utility model further provides a battery pack, comprising the battery unit in the first aspect.

[0015] Beneficial effects: Since the battery pack includes a battery cell, it has the same effects as the battery cell, which will not be described in detail here.

[0016] In an optional embodiment, the battery cell is provided in plurality and the plurality of battery cells are stacked and installed.

[0017] Beneficial effects: By stacking and installing multiple battery cells, it is easy to realize series and parallel connection between batteries, reducing the use of other structural parts, facilitating the improvement of the energy density of the battery pack and reducing costs.

[0018] In an optional embodiment, among the multiple battery cells, two adjacent battery cells include a first battery cell and a second battery cell, and the positive electrode shell of the first battery cell is in contact with the negative electrode shell of the second battery cell, so that the adjacent first battery cell and the second battery cell are arranged in series; wherein the battery pack also includes an insulating film, and the insulating film is used to be arranged between the negative electrode shell of the first battery cell and the positive electrode shell of the second battery cell.

[0019] Beneficial effect: By providing an insulating film between the negative electrode shell of the first battery cell and the positive electrode shell of the second battery cell, a short circuit phenomenon is avoided after the positive electrode shell of the first battery cell is brought into contact with the negative electrode shell of the second battery cell.

[0020] In an optional embodiment, among the multiple battery cells, the positive electrode shell of any battery cell contacts the positive electrode shell of an adjacent battery cell, and the negative electrode shell of any battery cell contacts the negative electrode shell of an adjacent battery cell, so that the multiple battery cells are arranged in parallel.

[0021] In an optional embodiment, the insulating ring in any battery cell is welded to the insulating ring in an adjacent battery cell.

[0022] Beneficial effect: By welding the insulating rings of two adjacent battery cells, it is easy to connect and fix the two adjacent battery cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the specific implementation modes of the present invention, the drawings required for use in the description of the specific implementation modes will be briefly introduced below. Obviously, the drawings described below are some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Figure 1 A schematic diagram of the structure of a battery unit provided by the utility model;

[0025] Figure 2 A schematic diagram of the structure of a battery cell in a battery unit provided by the utility model;

[0026] Figure 3 This is a schematic diagram of the structure of the battery pack provided by the utility model when adjacent battery cells are connected in series;

[0027] Figure 4 This is a schematic diagram of the structure of the battery pack provided by the present invention when adjacent battery cells are connected in parallel.

[0028] Description of reference numerals:

[0029] 1. Shell; 101. Positive electrode shell; 102. Negative electrode shell; 103. Fixing part;

[0030] 2. Insulation ring;

[0031] 3. Battery cell; 301. Positive electrode column; 302. Negative electrode column; 303. Battery body. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0033] In the description of the present application, it should be understood that the terms "vertical", "horizontal", "inner", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application 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, and therefore should not be understood as a limitation on the present application.

[0034] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0035] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0036] In conventional technology, one end of a cylindrical battery is a positive electrode and the other end is a negative electrode. Due to its small size, its capacity is low. Therefore, in actual processing, in order to achieve capacity expansion, multiple cylindrical batteries are arranged side by side, and the positive electrodes of each cylindrical battery are continuously welded. For example, for the positive electrode, a connecting member is used to weld the positive electrode of each cylindrical battery. However, after multiple weldings, if the welding quality between any of the positive electrodes and the adjacent positive electrodes is poor, the battery circuit may be blocked, leading to thermal runaway. To this end, the present application eliminates the welding process and reduces production costs by directly contacting the positive electrode column and the negative electrode column with two insulated metal shells respectively.

[0037] Specifically, see Figures 1 to 4 , Figure 1 A schematic diagram of the structure of a battery unit provided by the present application is shown; Figure 2 A schematic diagram showing the structure of a battery cell in a battery unit provided by the present application is shown; Figure 3 It shows a schematic structural diagram of adjacent battery cells in the battery pack provided by the present application connected in series; Figure 4 A schematic diagram of the structure when adjacent battery cells in the battery pack provided by the present application are connected in parallel is shown.

[0038] Combine the following Figures 1 to 4 , describing an embodiment of the utility model.

[0039] In a first aspect, the present application provides a battery unit, comprising a housing 1 , an insulating ring 2 and a battery cell 3 .

[0040] Specifically, the shell 1 is made of a metal shell, and the shell 1 includes a first shell and a second shell. The first shell and the second shell are arranged opposite to each other, and the end of the first shell close to the second shell and the end of the second shell close to the first shell are both provided with openings, and the two openings are connected so that the first shell and the second shell are enclosed to form a closed installation chamber. In the first shell and the second shell, one of them is a positive electrode shell 101, and the other is a negative electrode shell 102; the insulating ring 2 is installed between the two openings along the height direction, and is used to seal and insulate the first shell and the second shell; a plurality of battery cells 3 are provided, and the plurality of battery cells 3 are all arranged inside the shell 1, and the positive pole posts 301 of the plurality of battery cells 3 are all in contact with the inner wall surface of the positive electrode shell 101, and the negative pole posts 302 of the plurality of battery cells 3 are all in contact with the inner wall surface of the negative electrode shell 102.

[0041] By using the technical solution of this embodiment, the shell 1 is made into a metal shell so that the shell 1 has the ability to conduct electricity; one of the first shell and the second shell is the positive electrode shell 101, and the other is the negative electrode shell 102, and an insulating ring 2 is used to be arranged between the openings of the two shells so that the positive electrode shell 101 is insulated from the negative electrode shell 102; after the positive electrode column 301 of the battery cell 3 is directly in contact with the inner wall surface of the positive electrode shell 101, the positive electrode shell 101 is the positive electrode of the battery cell, and after the negative electrode column 302 of the battery cell 3 is directly in contact with the inner wall surface of the negative electrode shell 102, the negative electrode shell 102 is the negative electrode of the battery cell. Compared with the existing solution of continuously welding adjacent positive electrodes, the battery unit of this structure can be used for power supply by making the positive electrode column 301 and the negative electrode column 302 of the battery cell 3 directly contact with the metal shell, avoiding thermal runaway caused by low welding quality between some positive electrodes; at the same time, it also reduces production costs by omitting the welding process; in addition, through direct contact, electrical connectors can be omitted, thereby reducing the internal resistance of the battery unit and improving the energy density of the battery unit.

[0042] Preferably, in this embodiment, the first shell is the positive electrode shell 101 ; the second shell is the negative electrode shell 102 .

[0043] Preferably, in this embodiment, the height of the insulating ring 2 (the height of the insulating ring 2 refers to the height of the insulating ring 2 at Figure 1 The vertical dimension in the middle is H≥5mm. By setting the height of the insulating ring to H≥5mm, the insulation between the first shell and the second shell can be better guaranteed. And, as mentioned later, after the battery cell and other battery cells are connected in series or in parallel to form a battery pack, controlling the height of the insulating ring 2 can also ensure that the battery cell and the adjacent battery cells can be connected in series or in parallel according to the set idea. For example, according to Figure 3In the figure, if the first battery cell and the second battery cell need to be connected in series, it is necessary to ensure that the positive electrode housing 101 of the first battery cell is in contact with the negative electrode housing 102 of the second battery cell; due to the tolerance of the battery cell assembly, if the height of the insulating ring 2 is too small, the positive electrode housing 101 of the first battery cell may be in contact with the negative electrode housing 102 of the second battery cell while the positive electrode housing 101 of the first battery cell is in contact with the positive electrode housing 101 of the second battery cell. In order to avoid this problem, the height of the insulating ring 2 can be adjusted to H ≥ 5 mm.

[0044] It can be explained that, in the present application, there is no specific limitation on the fixing method between the insulating ring 2, the first shell and the second shell.

[0045] As one implementation manner, the insulating ring 2 and the first shell body as well as the insulating ring 2 and the second shell body are fixed by welding using heat sealing.

[0046] Of course, in other optional embodiments, a pair of oppositely arranged annular plug-in grooves are provided on the insulating ring 2, so that the edges at the opening of the first shell and the edges at the opening of the second shell are respectively inserted into the plug-in grooves to achieve fixation.

[0047] It can be explained that, in the present application, there is no specific limitation on the material of the insulating ring 2. Preferably, the insulating ring 2 is made of non-polar, thermoplastic plastic, such as polytetrafluoroethylene (PTFE), polyphenylene sulfide (PPS), polypropylene (PP), etc.

[0048] like Figure 1 As shown, the inner wall surface of the first shell and the inner wall surface of the second shell are both provided with a fixing portion 103 , and the fixing portion 103 is used to fix the positive electrode column 301 or the negative electrode column 302 .

[0049] By utilizing the technical solution of this embodiment, by providing a fixing portion 103 on the inner wall surfaces of the first shell and the second shell, the positive electrode column 301 and the negative electrode column 302 are fixed to avoid misalignment between the positive electrode column 301 and the inner wall surface of the positive shell 101, or avoid misalignment between the negative electrode column 302 and the inner wall surface of the negative shell 102, thereby avoiding circuit failure and making the circuit more reliable and stable when powering on.

[0050] It can be explained that, in the present application, the fixing portion 103 is provided with a through hole, one end of which is fixed to the inner wall surface of the positive electrode shell 101 or the inner wall surface of the negative electrode shell 102, and the other end extends toward the direction of the battery body 303 to play a guiding role. During installation, the positive electrode column 301 or the negative electrode column 302 is inserted into the through hole until it contacts the inner wall surface of the positive electrode shell 101 or the inner wall surface of the negative electrode shell 102.

[0051] like Figure 1 As shown, in the present application, the battery cell 3 is consistent with a conventional battery cell. Therefore, the battery cell 3 further includes a battery body 303 .

[0052] It can be explained that there is no specific limitation on the arrangement positions of the positive electrode column 301 and the negative electrode column 302 , and the positive electrode column 301 and the negative electrode column 302 only need to be arranged at two ends of the shell 1 .

[0053] Preferably, the positive electrode column 301 and the negative electrode column 302 are respectively arranged at two opposite ends of a pair of battery body 303, and the positive electrode column 301 and the negative electrode column 302 are both arranged outside the battery body 303. The height dimension of any fixing portion 103 is smaller than the height dimension of the positive electrode column 301 or the negative electrode column 302 fixedly connected to the fixing portion 103.

[0054] By utilizing the technical solution of this embodiment, the battery cell 3 includes a battery body 303, and the positive electrode column 301 and the negative electrode column 302 are both arranged outside the battery body 303. At this time, by making the height dimension of the fixing portion 103 smaller than the height dimension of the positive electrode column 301 or the negative electrode column 302 fixedly connected to the fixing portion 103, a gap can be left between any fixing portion 103 and the battery body 303, ensuring that the positive electrode column 301 is in contact with the positive electrode shell 101, and ensuring that the negative electrode column 302 is in contact with the negative electrode shell 102.

[0055] Further, in this application, the height dimension mentioned above is Figures 1 to 4 The inner vertical dimension.

[0056] Of course, in other optional implementations, the positive electrode column 301 and the negative electrode column 302 may be respectively arranged at two adjacent ends of the battery body 303. Since this method is a conventional method, it will not be described here.

[0057] It can be explained that, in the present application, the material of the housing 1 is not specifically limited, for example, the material of the housing 1 is aluminum, aluminum alloy or stainless steel. Preferably, the housing 1 is made of aluminum.

[0058] It can be explained that, in the present application, there is no specific limitation on the shape of the housing 1. For example, the housing 1 is a square housing or a cylindrical housing. Preferably, the housing 1 is square.

[0059] In a second aspect, the utility model further provides a battery pack, comprising the battery unit in the first aspect.

[0060] like Figure 3 and Figure 4 As shown, there are multiple battery cells, and in this case, the multiple battery cells are stacked and installed.

[0061] By utilizing the technical solution of this embodiment, multiple battery units are stacked and installed to facilitate series and parallel connection between batteries, reduce the use of other structural parts, and facilitate improving the energy density of the battery pack and reducing costs.

[0062] It can be explained that, in the present application, there is no specific limitation on the direction in which the multiple battery cells are stacked.

[0063] As one of the implementation methods, Figure 3 and Figure 4 As shown, multiple battery cells are Figure 3 and Figure 4 Horizontally stacked.

[0064] Of course, in other optional embodiments, multiple battery cells are stacked in a vertical direction.

[0065] like Figure 3 and Figure 4 As shown, among the multiple battery cells, two adjacent battery cells are defined as a first battery cell and a second battery cell.

[0066] It can be explained that, in the present application, there is no specific limitation on the connection mode between adjacent first battery units and second battery units, which can be connected in series or in parallel.

[0067] As one of the implementation methods, Figure 3 As shown, the first battery cell and the second battery cell are connected in series. At this time, the positive electrode shell 101 of the first battery cell is in contact with the negative electrode shell 102 of the second battery cell. In order to avoid short circuit, the battery pack also includes an insulating film, which is used to be arranged between the negative electrode shell 102 of the first battery cell and the positive electrode shell 101 of the second battery cell.

[0068] By using the technical solution of this embodiment, an insulating film is provided between the negative electrode shell 102 of the first battery cell and the positive electrode shell 101 of the second battery cell, so that a short circuit can be avoided after the positive electrode shell 101 of the first battery cell is brought into contact with the negative electrode shell 102 of the second battery cell.

[0069] As another embodiment, Figure 4 As shown, two adjacent battery cells are connected in parallel.

[0070] Specifically, among the plurality of battery cells, the positive electrode casing 101 of any battery cell contacts the positive electrode casing 101 of an adjacent battery cell, and the negative electrode casing 102 of any battery cell contacts the negative electrode casing 102 of an adjacent battery cell, so that the plurality of battery cells are arranged in parallel.

[0071] Of course, in other optional implementations, when the number of battery cells in the battery pack is more than three, some of the battery cells are connected in series, and other battery cells are connected in parallel.

[0072] It can be explained that, in the above embodiment, the insulating ring 2 in any battery cell is welded to the insulating ring 2 in the adjacent battery cell.

[0073] By utilizing the technical solution of this embodiment, the insulating rings 2 of two adjacent battery cells are welded, thereby facilitating the connection and fixation of two adjacent battery cells.

[0074] In some embodiments, the battery pack further includes a battery pack housing, and the plurality of battery cells can be placed in the battery pack housing after being stacked and installed.

[0075] Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A battery cell, characterized in that: include: A shell (1), the shell (1) being a metal shell, the shell (1) comprising a first shell and a second shell, the first shell and the second shell being arranged opposite to each other, and an end of the first shell close to the second shell and an end of the second shell close to the first shell are both provided with openings, the two openings being connected so that the first shell and the second shell are enclosed to form a closed installation chamber, and one of the first shell and the second shell is a positive electrode shell (101) and the other is a negative electrode shell (102); An insulating ring (2), the insulating ring (2) being installed between the two openings in a height direction and used for sealing and insulating the first shell and the second shell; A battery cell (3), wherein a plurality of the battery cells (3) are provided, the plurality of battery cells (3) are all arranged inside the shell (1), the positive pole posts (301) of the plurality of battery cells (3) are all in contact with the inner wall surface of the positive shell (101), and the negative pole posts (302) of the plurality of battery cells (3) are all in contact with the inner wall surface of the negative shell (102).

2. The battery cell according to claim 1, characterized in that: The inner wall surface of the first shell and the inner wall surface of the second shell are both provided with a fixing portion (103), and the fixing portion (103) is used to fix the positive electrode column (301) or the negative electrode column (302).

3. The battery cell according to claim 2, characterized in that: The battery cell (3) further includes a battery body (303); The positive electrode column (301) and the negative electrode column (302) are respectively arranged at two opposite ends of a pair of the battery body (303), and the positive electrode column (301) and the negative electrode column (302) are both arranged outside the battery body (303); The height dimension of any one of the fixing portions (103) is smaller than the height dimension of the positive electrode column (301) or the height dimension of the negative electrode column (302) fixedly connected to the fixing portion (103).

4. The battery cell according to any one of claims 1 to 3, characterized in that: The shell (1) is made of aluminum, aluminum alloy or stainless steel.

5. The battery cell according to any one of claims 1 to 3, characterized in that: The housing (1) is a square housing.

6. The battery cell according to any one of claims 1 to 3, characterized in that: The height H of the insulating ring (2) is ≥5 mm.

7. A battery pack, characterized in that: A battery cell comprising any one of claims 1 to 6, The battery cells are provided in plurality and are stacked and installed.

8. The battery pack according to claim 7, characterized in that: Among the plurality of battery cells, two adjacent battery cells include a first battery cell and a second battery cell, and the positive electrode shell (101) of the first battery cell contacts the negative electrode shell (102) of the second battery cell, so that the adjacent first battery cell and the second battery cell are arranged in series; The battery pack further comprises an insulating film, wherein the insulating film is used to be arranged between the negative electrode casing (102) of the first battery unit and the positive electrode casing (101) of the second battery unit.

9. The battery pack according to claim 7, characterized in that: Among the plurality of battery cells, the positive electrode casing (101) of any battery cell contacts the positive electrode casing (101) of an adjacent battery cell, and the negative electrode casing (102) of any battery cell contacts the negative electrode casing (102) of an adjacent battery cell, so that the plurality of battery cells are arranged in parallel.

10. The battery pack according to any one of claims 7 to 9, characterized in that: The insulating ring (2) in any battery cell is welded to the insulating ring (2) in an adjacent battery cell.

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