CN218005128U

CN218005128U - Group battery, battery package and car

Info

Publication number: CN218005128U
Application number: CN202221459188.2U
Authority: CN
Inventors: 赵冬
Original assignee: China Lithium Battery Technology Co Ltd
Current assignee: China Lithium Battery Technology Co Ltd
Priority date: 2022-06-10
Filing date: 2022-06-10
Publication date: 2022-12-09
Anticipated expiration: 2032-06-10

Abstract

The application provides a group battery, battery package and car, this group battery includes: at least two batteries, wherein two opposite surfaces of two adjacent batteries are bonded and connected to form a bonding area, at least one of the two opposite surfaces is provided with a connection area exposed out of the battery shell, and the connection area is at least partially covered by the bonding area. In the technical scheme, the exposed connecting area of the shell is adopted, so that the bonding strength between the batteries is improved, and meanwhile, the insulating strength between the batteries is ensured.

Description

Battery pack, battery pack and automobile

Technical Field

The application relates to the technical field of batteries, in particular to a battery pack, a battery pack and an automobile.

Background

In the battery pack manufacturing process, a plurality of cells need to be bonded in a row. In order to ensure the insulation between the batteries, an insulating layer is coated outside the batteries, but the thickness of the insulating layer is not too thick generally, and when the battery pack is subjected to external force, the insulating layer is easy to tear, so that the connection effect between the batteries is damaged.

SUMMERY OF THE UTILITY MODEL

The application provides a group battery, battery package and car for improve the adhesion strength of battery between the group battery.

In a first aspect, there is provided a battery pack including: the battery comprises at least two batteries, wherein two opposite surfaces of two adjacent batteries are bonded and connected to form a bonding area, at least one of the two opposite surfaces is provided with a connection area exposed out of a battery shell, and the connection area is at least partially covered by the bonding area. In the technical scheme, the exposed connecting area of the shell is adopted, so that the bonding strength between the batteries is improved, and the insulation strength between the batteries is ensured.

In a second aspect, there is provided a battery pack comprising a housing, and the battery pack of any one of the above items disposed within the housing. In the technical scheme, the exposed connecting area of the shell is adopted, so that the bonding strength between the batteries is improved, and the insulation strength between the batteries is ensured.

In a third aspect, there is provided an automobile comprising an automobile body, and a battery pack as described in any one of the above, or a battery pack as described above, provided on the automobile body. In the technical scheme, the exposed connecting area of the shell is adopted, so that the bonding strength between the batteries is improved, and the insulation strength between the batteries is ensured.

Drawings

Fig. 1 is a schematic structural diagram of a battery pack provided in an embodiment of the present application;

fig. 2 is a schematic structural diagram of a battery provided in an embodiment of the present application;

fig. 3 is a schematic structural diagram of connection between batteries according to an embodiment of the present disclosure;

fig. 4 is a schematic structural diagram of another connection between batteries according to an embodiment of the present disclosure.

Detailed Description

The present application is described in further detail below with reference to the figures and examples. The features and advantages of the present application will become more apparent from the description.

The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

In addition, the technical features related to the different embodiments of the present application described below may be combined with each other as long as they do not conflict with each other.

To facilitate understanding of the battery pack provided in the embodiments of the present application, the structure of the battery pack is first described, and the battery pack includes a plurality of batteries, and the plurality of batteries are arranged in one battery pack. When the batteries are arranged into a battery pack, the batteries are connected in an adhesive manner. In addition, in order to improve the insulativity between the batteries, each battery is wrapped by an insulating film layer, and the batteries are connected by the adhesion between the insulating film layers when being connected by adhesion. However, the insulating film layer is thin, and the insulating film layer is easy to tear when the battery is stressed, so that the insulating performance of the battery is affected. To this end, embodiments of the present application provide a battery pack to improve the strength of adhesion between cells and insulation. The details of which are set forth in the accompanying drawings and the examples below.

Referring to fig. 1, the battery pack provided by the embodiment of the present application includes at least two batteries 10, and adjacent two batteries 10 of the at least two batteries 10 are adhesively connected to each other. Illustratively, the battery pack may include two or more batteries 10, and the batteries 10 may be arranged in a single row or a plurality of rows. In the present embodiment, the adhesive connection between the adjacent cells 10 means an adhesive connection between the cells 10 located in the same row.

When the adjacent two batteries 10 are bonded, they are bonded and connected by the opposite surfaces of the adjacent two batteries 10. Illustratively, the cell 10 has oppositely disposed top and bottom surfaces, and four side surfaces. The top surface is the surface that is provided with utmost point ear, and the bottom surface is the surface relative with the top surface, and four sides are located between top surface and the bottom surface. The side surface is divided into a large side surface and a small side surface according to the size, wherein the small side surface is the side surface with smaller area in the side surface, and the large side surface is the side surface with larger area in the side surface. I.e., the sides of the battery 10, has two small opposite sides and two large opposite sides.

When the cells 10 are connected to each other, the adjacent cells 10 are connected to each other by side adhesion. Specifically, the small side surfaces of two adjacent batteries are arranged oppositely, and the two opposite small side surfaces are bonded and connected; of course, when two large sides are oppositely arranged, the two large sides can be bonded and connected. In the specific connection, the two batteries 10 can be connected by an adhesive, that is, the adhesive (not shown) is adhered between two opposite surfaces of the two adjacent batteries 10, and the two batteries 10 are adhered and connected by the adhesive. The adhesive can be, for example, a structural adhesive, a glue, a tape, or the like.

When the adhesive glue is arranged, the larger the thickness of the adhesive glue is, the higher the adhesive strength between the battery 10 and the battery 10 is, but when the thickness of the adhesive glue is too large, the gap between the battery 10 and the battery 10 is too large, the whole weight and the whole volume of the battery pack are large, and the whole space utilization rate and the energy density in the battery 10 pack are influenced.

When the insulating layer is provided on the battery 10, the insulating layer may be provided on each battery 10 in the embodiment of the present application, or may be provided on a part of the batteries 10. That is, in at least two of the cells 10 disclosed in the present application, the housing of at least some adjacent cells is wrapped with an insulating layer. In order to ensure the insulation of the battery without the insulating layer, a sufficient gap needs to be maintained between the battery and the insulating layer.

When the insulating layer is coated on the outer surface of the battery 10 case, the thickness of the insulating layer is too large, which increases the assembly size of the battery 10 and is not beneficial to improving the energy density of the whole battery 10 pack; if the thickness is too small, the insulating performance of the battery 10 is not good. Therefore, the thickness of the insulating layer provided is not too thick in general, and the structural strength is not too high. In the embodiment of the present application, the insulating layer may be an insulating coating layer coated or sprayed on the battery case with an insulating paint; the insulating layer can also be an insulating film layer which can be directly coated on the battery shell.

The joint strength between insulating layer and the insulating layer is less than the joint strength who compares in battery case and casing, consequently when through insulating layer bonding connection between battery and the battery, the insulating layer is easy for the atress to deviate from battery case, leads to battery and battery to be difficult to be connected fixedly, and the insulating layer of deviating from simultaneously leads to the battery to have the risk of insulation failure.

Referring to fig. 2, in order to improve the connection strength between two cells 10, adhesive regions are formed at opposite surfaces of two adjacent cells 10 by adhesive connection, and at least one of the opposite surfaces has a connection region 11 where a battery case is exposed. The exposed connecting region 11, i.e. the surface of the battery case, is not provided with other structures, and the battery case is directly bonded with the connected batteries, and the bonding region refers to the region where the batteries are bonded with each other when the batteries are bonded with each other. The bonding region is the region where the bonding glue is bonded to the battery when bonded.

In the case of adhesive bonding, the connecting region 11 is at least partially covered by the adhesive bonding region. The case of the battery 10 is directly exposed at the location of the connection region 11. When two adjacent batteries 10 are connected, the fact that the connection region 11 is at least partially covered by the bonding region means that: the adhesive can be directly adhesively bonded to the case of the battery 10, thereby improving the bonding strength of the battery 10 during the bonding.

For the connection region 11 to be formed, it is at least partly not covered with the insulating layer 12. That is, when the connection region 11 is provided, all regions in the connection region 11 are exposed, or only some regions of the housing are exposed.

When the connection region 11 is formed, different methods may be adopted, such as the insulating layer 12 directly avoiding the connection region 11 to form an exposed case; or the insulating layer 12, which each cell 10 wraps around, has a window corresponding to the connection region 11, forming a case exposed. I.e., a window is opened in the insulating layer 12 so that the housing portion of the battery 10 is exposed. When the window is specifically opened, the opening position can be set at the position and the area can be adjusted according to the requirement. The position and area of the opening of the insulating layer 12 are indicated by the connection region 11.

When the connection region 11 is provided, the connection region 11 may be located at different positions on the surface, and for example, the connection region 11 may be located at a middle region of the surface, or at different positions such as an edge region of the surface. Preferably, the connecting region 11 is located in the middle region of the surface, so that during the bonding, the adhesive can also be located in the middle region. The middle area refers to an area surrounding the center of the surface where the connecting area is located, and the middle area can be an area with different shapes such as a circle, a direction, an ellipse and the like.

For the shape of the connection region 11, different shapes may be selected. Illustratively, the shape of the connecting region 11 may be a circle, an ellipse, or a polygon such as a rectangle, a prism, or may be a special shape. As one preferable shape, the shape of the connection region 11 is in a regular pattern such as a rectangle, an ellipse or a circle so that the insulating layer 12 is windowed.

In addition, as for the area of the connection region 11, when provided, the ratio of the area of the connection region 11 to the surface of the battery case where the connection region 11 is located is 0.1 to 0.9. I.e., the ratio of the area of the connecting region 11 to the area of the surface on which it is disposed, is between 0.1 and 0.9, and illustratively, the ratio of the area of the connecting region 11 to the area of the surface on which it is disposed is a different ratio of 0.1, 0.3, 0.6, 0.9, etc.

In forming the connection regions 11, both surfaces of the two cells 10 facing each other may have the connection regions 11, respectively, or only one of the cells 10 may have the connection region 11. Two cases will be described below.

Referring to fig. 3, a structure of a shielded portion when the battery is connected to the battery is illustrated with a dotted line in order to illustrate a connection manner of the adhesive 20 to the battery. To describe the connection of the two batteries in terms of aspects, the two batteries are respectively named a first battery 10a and a second battery 10b.

When the first battery 10a and the second battery 10b are connected, the opposite surfaces are adhesively connected by the adhesive paste 20, and the adhesive paste 20 may be sized to cover a portion of the connection region 11, or the adhesive paste 20 may cover at least the connection region 11. Preferably, the adhesive 20 is provided to cover at least the connection region 11, so that the coated area of the adhesive 20 is large, thereby improving the connection strength between the batteries 10.

When only one cell has a connection region, that is, one of the bonding regions on the opposite surfaces of the adjacent cells has a connection region. For convenience of description, the first cell 10a is exemplified to have the connection region 11, and the second cell 10b is exemplified not to have the connection region.

When the first battery 10a and the second battery 10b are connected by the adhesive 20, the thickness of the adhesive 20 and the thickness of the insulating layer both affect the energy density of the battery pack, and therefore the thickness of the adhesive 20 is not necessarily too large at the time of installation. But also needs to consider the insulating property between the batteries to avoid that the insulating property between the batteries can not meet the requirement due to the windowing of the insulating layer on one battery. In order to satisfy the above conditions, when the case of the first cell 10a and the insulating layer of the second cell 10b are adhesively connected by the adhesive 20, the resistance between the adjacent two cells (the first cell 10a and the second cell 10 b) satisfies:

wherein d1 and d2 are thicknesses of the insulating layers of the two adjacent surfaces; d3 is the thickness of the bonding region; s1 and s2 are the areas of the insulating layers of the two adjacent surfaces; s3 is the area of the linking region; ρ 1 and ρ 2 are volume resistivities of the insulating layers of the adjacent two surfaces, and ρ 3 is a volume resistivity of the adhesion region.

In the above formula, the insulation performance between the batteries is determined by the adhesive and the insulation layer. It can be seen from the layer structure between the batteries that along the direction that one battery points to the other battery, the current path is connected in parallel by the insulating film at the position without the window and the adhesive glue at the position with the window, and then connected in series with the insulating film of the other battery.

The data satisfy: the thickness d3 of the adhesive is 0.2 mm-3 mm and/or the thicknesses d1 and d2 of the insulating layer are both less than or equal to 0.14mm. Namely the thickness d3 of the adhesive can be between 0.2mm and 3mm, and the thicknesses d1 and d2 of the insulating layers are both less than or equal to 0.14mm; or the thickness d3 of the adhesive is 0.2 mm-3 mm or the thicknesses d1 and d2 of the insulating layers are both less than or equal to 0.14mm. When the data are selected, the data need to be selected according to the resistance between the batteries, namely the resistance between the batteries needs to meet the requirement of being more than or equal to 15M omega, so that the resistivity between the batteries meets the insulation requirement.

Referring to table 1, table 1 illustrates the parameters of the insulating layer, the adhesive paste 20, and the connection region when the insulating layer on one cell is windowed (single-sided windowed).

TABLE 1

Thickness d3 of the adhesive	0.2mm～3mm
		Volume conductivity omega cm of adhesive	10E12-10E13
Thicknesses d1, d2 of the insulating layer	≤0.14mm
		Area of	S1＝S2，S3/S2＝10-90％

When the single-side windowing is adopted, the thickness d3 of the adhesive, the thicknesses d1 and d2 of the insulating layers, the areas S1 and S2 of the insulating layers and the area S3 of the connecting area are required to ensure that the resistance value between the two batteries is greater than 15M omega when the data of the table 1 are adopted, so that the requirement on insulation between the batteries is met.

Referring to fig. 4, when a double window is employed between the cells, two bonding regions of the opposite surfaces of the first cell 10a and the second cell 10b have a connection region 11a and a connection region 11b, respectively.

The joining region 11a and the joining region 11b are oppositely disposed. And the two connection regions 11 overlap at least in regions. That is, when the two connection areas 11 are disposed opposite to each other, the adhesive 20 is at least partially connected to the connection areas 11 on both sides.

When the connection region 11a and the connection region 11b are specifically provided, there can be employed: the connection region 11a and the connection region 11b completely overlap, or the connection region 11a and the connection region 11b are arranged in a staggered manner, but a partial region overlaps. It is thereby ensured that both sides of the adhesive 20 can be connected to the

connection regions

11a and 11b, i.e. directly to the housing of the first battery 10a and the second battery 10b, during the adhesive bonding.

When the batteries adopt the double window, the resistance between the adjacent two batteries (the first battery 10a and the second battery 10 b) satisfies:

wherein d1 and d2 are thicknesses of the insulating layers of the two adjacent surfaces; d3 is the thickness of the bonding region; s1 and s2 are the areas of the insulating layers of the two adjacent surfaces; s3 is the area of the joining region (the joining region 11a and the joining region 11b completely overlap); ρ 1 and ρ 2 are volume resistivities of the insulating layers of the adjacent two surfaces, and ρ 3 is a volume resistivity of the adhesion region.

In the above formula, the insulation performance between the batteries is determined by the adhesive and the insulation layer. It can be seen from the layer structure between the batteries that along the direction that one battery points to the other battery, the current path is that the two insulation films at the positions where the windows are not opened are connected in parallel with the adhesive glue at the positions where the windows are opened and then connected in series.

The data satisfy: the thickness d3 of the adhesive is 0.8 mm-5 mm and/or the thicknesses d1 and d2 of the insulating layers are less than or equal to 0.14mm. Namely, the thickness d3 of the adhesive is between 0.2mm and 3mm, and the thicknesses d1 and d2 of the insulating layers are both less than or equal to 0.14mm; or the thickness d3 of the adhesive is between 0.2mm and 3mm or the thicknesses d1 and d2 of the insulating layers are both less than or equal to 0.14mm. When the data are selected, the data need to be selected according to the resistance between the batteries, namely the resistance between the batteries needs to meet the requirement of being more than or equal to 15M omega, so that the resistivity between the batteries meets the insulation requirement.

Referring to table 2, table 2 illustrates the parameters of the insulating film, the adhesive paste, and the connection region when the insulating film on the two cells is windowed.

TABLE 2

When the two-side windowing is adopted, the thickness d3 of the adhesive, the thicknesses d1 and d2 of the insulating layers, the areas S1 and S2 of the insulating layers and the area S3 of the connecting area are required to ensure that the resistance value between the two batteries is greater than 15M omega when the data of the table 2 are adopted, so that the requirement on the insulation between the batteries is met.

The above examples illustrate only two specific cell connection types of resistors. When the adhesive completely covers the connection region and is connected to a part of the insulating layer, the corresponding resistance may be subjected to deformation calculation according to the principles of the formulas in the above two cases, which is not described in detail in the embodiments of the present application. Similarly, for the setting mode that two connection areas are adopted and the two connection areas are staggered, the corresponding calculation mode of the resistance may also adopt the principle of the formulas of the above two cases for performing the deformation calculation, which is not described in detail in the embodiment of the present application.

As can be seen from the above embodiments, in the battery pack for the embodiment of the present application, by using the connection region for applying the insulating layer, the adhesive strength between the batteries is improved while the insulating strength between the batteries is ensured.

The embodiment of the application also provides a battery pack, which comprises a shell and the battery pack arranged in the shell. In the technical scheme, the exposed connecting area of the shell is adopted, so that the bonding strength between the batteries is improved, and the insulation strength between the batteries is ensured.

The embodiment of the application provides an automobile, which comprises an automobile body and the battery pack or the battery pack arranged on the automobile body. In the technical scheme, the exposed connecting area of the shell is adopted, so that the bonding strength between the batteries is improved, and meanwhile, the insulating strength between the batteries is ensured.

In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer", "front", "rear", "left", "right", and the like indicate orientations or positional relationships based on operational states of the present application, and are only used for convenience in describing and simplifying the present application, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present application.

In the description of the present application, it should be noted that the terms "mounted," "connected," and "connected" are to be construed broadly unless otherwise explicitly specified or limited. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

The present application has been described above in connection with preferred embodiments, which are intended to be exemplary only and illustrative only. On the basis of the above, the present application can be subjected to various substitutions and improvements, and the substitutions and the improvements are all within the protection scope of the present application.

Claims

1. A battery pack, comprising: at least two batteries, wherein two opposite surfaces of two adjacent batteries are bonded and connected to form a bonding area, at least one of the two opposite surfaces is provided with a connection area exposed out of the battery shell, and the connection area is at least partially covered by the bonding area.

2. The battery of claim 1, wherein the housing of at least some adjacent ones of the at least two cells are surrounded by an insulating layer; and the connection region is at least partially not covered with an insulating layer.

3. The battery according to claim 1, wherein the bonding areas of the two opposing surfaces are adhesively connected by a bonding glue, and the bonding glue covers at least the connection area.

4. The battery according to any one of claims 1-3, wherein one of the bonding areas of the opposing surfaces has the attachment area.

5. The battery pack according to claim 4, wherein the resistance between the adjacent two cells satisfies:

wherein d1 and d2 are the thicknesses of the insulating layers of the two adjacent surfaces; d3 is the thickness of the adhesive region; s1 and s2 are the areas of the insulating layers of the two adjacent surfaces; s3 is the area of the linking region; ρ 1 and ρ 2 are volume resistivities of the insulating layers of the adjacent two surfaces, and ρ 3 is a volume resistivity of the adhesion region.

6. The battery according to claim 5, wherein the thickness d3 of the adhesive region is between 0.2mm and 3mm; and/or the presence of a gas in the gas,

the thicknesses d1 and d2 of the insulating layers are less than or equal to 0.14mm.

7. The battery according to any one of claims 1 to 3, wherein two adhesive regions of the opposing surfaces have the connecting region, respectively, and the two connecting regions are disposed opposite to each other.

8. The battery pack according to claim 7, wherein the resistance between the adjacent two cells satisfies:

wherein d1 and d2 are the thicknesses of the insulating layers of the two adjacent surfaces; d3 is the thickness of the adhesive region; s1 and s2 are the areas of the insulating layers of the two adjacent surfaces; s3 is the area of the connecting region; ρ 1 and ρ 2 are volume resistivities of the insulating layers of the adjacent two surfaces, and ρ 3 is a volume resistivity of the adhesion region.

9. The battery of claim 8, wherein the thickness d3 of the adhesive region is between 0.8mm and 5mm; and/or the presence of a gas in the gas,

10. The battery according to any one of claims 1 to 3, wherein the ratio of the area of the connection region to the cell surface where the connection region is located is 0.1 to 0.9.

11. The battery according to claim 10, wherein the connection region has a shape of a rectangle, an ellipse, or a circle.

12. The battery as defined in claim 11, wherein the connection region is located at a middle region of the surface of the battery.

13. The battery according to any one of claims 1 to 3, wherein the cell comprises four side surfaces and two oppositely disposed top and bottom surfaces, the four side surfaces being located between the top and bottom surfaces; and the two adjacent batteries are connected through side bonding.

14. The battery pack according to claim 13, wherein the side having a smaller area among the four sides of the cell is a small side, and the small sides of the adjacent two cells are opposed to each other and are adhesively connected.

15. A battery pack comprising a case, and the battery pack according to any one of claims 1 to 14 disposed in the case.

16. An automobile comprising a vehicle body, and a battery pack according to any one of claims 1 to 14 or a battery pack according to claim 15 provided on the vehicle body.