Battery cell and battery pack

Abstract

Embodiments of the present disclosure provide a battery cell and a battery pack. The battery cell includes a bare cell, a flow guide sheet, and an insulating protective film. The bare cell includes a body having a first direction and a second direction intersecting each other, wherein the body includes a first end face at one end of the body in the first direction; and a tab disposed at the first end face of the body and extending to an outside of the first end face, wherein the tab includes a first side and a second side opposite to each other, and the tab further includes a first welding portion. The flow guide sheet is disposed on the first side of the tab and includes a second welding portion welded with the first welding portion. The insulating protective film includes a first insulating portion covering the second side of the tab, wherein a plurality of first adhesive layers are disposed on the first insulating portion, the plurality of first adhesive layers are spaced apart in the second direction and avoid the first welding portion, and the first insulating portion is connected to at least one of the tab and the flow guide sheet through the plurality of first adhesive layers.

Description

Technical Field

[0001] The embodiments disclosed herein relate to the field of battery technology, and in particular to a battery cell and a battery pack. Background Technology

[0002] A typical battery cell includes a casing, a top cover, electrode assemblies, and terminals. The casing has a receiving cavity and a top opening. The electrode assemblies can be placed into the receiving cavity of the casing through the top opening and can be sealed in the receiving cavity by the top cover. The terminals pass through the top cover and include positive and negative terminals.

[0003] Electrode assemblies may include bare cells and current-conducting tabs. A bare cell includes a body (also called a wound core) and tabs. The body can be formed by winding stacked positive electrode sheets, separators, and negative electrode sheets, or by alternately stacking positive electrode sheets, negative electrode sheets, and separators. Tabs include positive tabs connected to the positive electrode sheets and negative tabs connected to the negative electrode sheets. The positive / negative tabs extend outward from the end face of the body. A positive tab may include multiple stacked positive electrode tabs, each of which may be attached to a corresponding position on the positive electrode sheet or integrally formed with the positive electrode sheet. A negative tab may include multiple stacked negative electrode tabs, each of which may be attached to a corresponding position on the negative electrode sheet or integrally formed with the negative electrode sheet. Current-conducting tabs include positive and negative current-conducting tabs; positive tabs are welded to their corresponding positive current-conducting tabs, and negative tabs are welded to their corresponding negative current-conducting tabs. The positive electrode guide plate is connected to the corresponding positive electrode post, and the negative electrode guide plate is connected to the corresponding negative electrode post.

[0004] When the electrode assembly needs to be placed into the housing, the tabs are bent to move towards the end face of the body, thereby adjusting the position of the guide vanes. To prevent burrs on the edges of the tabs from puncturing the diaphragm, the electrode assembly may also include an insulating protective film (also known as insulating tape) to cover the tabs. When the tabs are bent, the insulating protective film separates the end face of the tabs from that of the body, effectively reducing the probability of burrs from the tabs puncturing the diaphragm.

[0005] In conventional insulating protective films, the side facing the tab is completely covered by an adhesive layer with consistent adhesion and uniform thickness, and the insulating protective film is bonded to the tab through the adhesive layer. However, during the expansion of the battery cell or bending of the tab, the adhesive layer of the insulating protective film will directly exert tensile force on the tab. The weakest points of the tab connection (such as the edge of the solder mark) are easily torn due to the pulling, thereby affecting the capacity and safety performance of the battery cell. Utility Model Content

[0006] In a first aspect of this disclosure, a battery cell is provided. The battery cell includes a bare cell, a current-conducting plate, and an insulating protective film. The bare cell includes: a body having intersecting first and second directions, wherein the body includes a first end face located at one end of the body along the first direction; and a tab disposed at the first end face of the body and extending to the outside of the first end face, wherein the tab includes a first side and a second side opposite to each other, and the tab also includes a first weld portion. The current-conducting plate is disposed on the first side of the tab and includes a second weld portion, the second weld portion being welded to the first weld portion. The insulating protective film includes a first insulating portion covering the second side of the tab, wherein a plurality of first adhesive layers are disposed on the first insulating portion, the plurality of first adhesive layers being spaced apart in the second direction and avoiding the first weld portion, and the first insulating portion being connected to at least one of the tab and the current-conducting plate through the plurality of first adhesive layers.

[0007] In some embodiments, the first insulating portion includes a first functional area and a plurality of first connection areas, the first functional area being located between and connected to the plurality of first connection areas, the first welding portion and the portion of the electrode adjacent to the first welding portion being covered by the first functional area, and a plurality of first adhesive layers being disposed on the plurality of first connection areas.

[0008] In some embodiments, the first insulating portion is rectangular, and wherein, in the second direction, the first functional area includes a rectangular region located at the middle position of the first insulating portion, and the plurality of first connecting areas include a plurality of rectangular regions located on both sides of the first functional area.

[0009] In some embodiments, the first insulating portion is rectangular, and a plurality of first connection areas are located at a plurality of corners of the first insulating portion.

[0010] In some embodiments, at least a portion of the plurality of first connection areas is provided with a first identification color block, or at least a portion of the plurality of first connection areas has an identification color.

[0011] In some embodiments, the first functional area is transparent, and / or the first functional area is not provided with an adhesive layer.

[0012] In some embodiments, the first functional area is provided with a second adhesive layer, wherein the material adhesion of the second adhesive layer is less than that of the first adhesive layer, and / or the thickness of the second adhesive layer is less than that of the first adhesive layer.

[0013] In some embodiments, the body further includes a second end face and a side face, the second end face being opposite to the first end face, the side face being located between the first end face and the second end face and including a first side face and a second side face that are opposite to each other; and the insulating protective film further includes a second insulating portion connected to the first insulating portion, the second insulating portion corresponding to the first end face and the first side face, wherein a third adhesive layer is disposed on the second insulating portion, and the second insulating portion is connected to at least one of the first end face and the first side face through the third adhesive layer.

[0014] In some embodiments, the second insulating portion includes a second functional area and a plurality of second connection areas, the second functional area being located between and connected to the plurality of second connection areas; and a plurality of third adhesive layers are disposed on the second insulating portion, the plurality of third adhesive layers being disposed on the plurality of second connection areas.

[0015] In some embodiments, the second insulating portion is rectangular, and wherein, in the second direction, the second functional area includes a rectangular region located at the middle position of the second insulating portion, and the plurality of second connecting areas include a plurality of rectangular regions located on both sides of the second functional area.

[0016] In some embodiments, a plurality of first connection areas and a plurality of second connection areas are connected in a one-to-one correspondence, and a plurality of first adhesive layers and a plurality of third adhesive layers are connected in a one-to-one correspondence.

[0017] In some embodiments, the second insulating portion is rectangular, and a plurality of second connection areas are located at a plurality of corners of the second insulating portion.

[0018] In some embodiments, at least a portion of the plurality of second connection areas is provided with a second identification color block, or at least a portion of the plurality of second connection areas has an identification color.

[0019] In some embodiments, the second functional area is transparent, and / or the second functional area is not provided with an adhesive layer.

[0020] In some embodiments, the second functional area is provided with a fourth adhesive layer, wherein the material adhesion of the fourth adhesive layer is less than that of the third adhesive layer, and / or the thickness of the fourth adhesive layer is less than that of the third adhesive layer.

[0021] In a second aspect of this disclosure, a battery pack is provided. The battery pack includes individual battery cells provided according to a first aspect of this disclosure.

[0022] According to the battery cell provided in this embodiment, the first insulating portion of the insulating protective film covering the second side of the tab is reliably connected to at least one of the tab and the current guide plate through a plurality of first adhesive layers with high adhesion. Simultaneously, the plurality of first adhesive layers are spaced apart in the second direction (the width direction of the bare cell body) and avoid the first welding portion of the tab. This effectively prevents the tab from being torn at the solder joint due to the multiple first adhesive layers with high adhesion directly pulling on the first welding portion of the tab during cell expansion or bending.

[0023] It should be understood that the content described in this section is not intended to limit the key or essential features of the embodiments of this disclosure, nor is it intended to restrict the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0024] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein: Figure 1 A top view schematic diagram showing a battery cell in a state before its two bare cells are joined together, according to some embodiments of the present disclosure; Figure 2 It shows Figure 1 The diagram shown is a side view of a single battery cell before its two bare cells are joined together. Figure 3 It shows Figure 1 A schematic diagram of the unfolded insulating protective film; Figure 4 It shows Figure 3 One implementation of the AA sectional view; Figure 5 It shows Figure 3 Another implementation of the AA section view; Figure 6 It shows Figure 3 One implementation of the BB cross-sectional view; Figure 7 It shows Figure 3 Another implementation of the BB section view; and Figure 8 It shows Figure 3 The diagram shows a modified embodiment of the insulating protective film. Detailed Implementation

[0025] Embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

[0026] The term "comprising" and its variations as used herein signify open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "at least partially based on". The terms "one example embodiment" and "one embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc., may refer to different or the same objects.

[0027] As described above, the conventional insulating protective film is completely covered by an adhesive layer with consistent adhesion and uniform thickness on the side facing the tab, and the insulating protective film is bonded to the tab by the adhesive layer. However, during the expansion of the battery cell or bending of the tab, the adhesive layer of the insulating protective film directly exerts a tensile force on the tab. Areas with weaker connection strength (such as solder joint edges) are easily torn due to this tension, thus affecting the capacity and safety performance of the battery cell. To solve the problem of easy tearing of the solder joint edges of the tab, embodiments of this disclosure provide a battery cell and a battery pack. In the following sections, [further details will be provided]. Figures 1 to 8 The principles of this disclosure are described.

[0028] Figure 1 A top view schematic diagram of a battery cell 100 according to some embodiments of the present disclosure in a state before its two bare cells 10 are joined together. Taking a joined cell as an example, the battery cell 100 specifically includes two bare cells 10, which have substantially the same structure and are arranged symmetrically. Figure 2 It shows Figure 1 The diagram shows a side view of a battery cell 100 before its two bare cells 10 are joined together. Figure 3 It shows Figure 1 A schematic diagram of the unfolded insulating protective film 30, in which... Figure 3 The boundary line between the first insulating part 301 and the second insulating part 302 is schematically shown in the dashed line. Figure 4 It shows Figure 3 One implementation of the AA sectional view in the diagram. Figure 5 It shows Figure 3 Another implementation of the AA section view in the diagram. Figure 6 It shows Figure 3 One implementation of the BB cross-sectional view. Figure 7 It shows Figure 3 Another implementation of the BB cross-sectional view.

[0029] See Figure 1 and Figure 2 The battery cell 100 provided in this embodiment may include a housing (not shown), a top cover 60, and an electrode assembly. The electrode assembly includes two bare cells 10 and at least two current-conducting plates 20. Each bare cell 10 includes a body 11 and at least two tabs 12. The housing of the battery cell 100 has a top opening, and after the two bare cells 10 are joined together, the electrode assembly can enter the housing through the top opening. The top cover 60 covers the top opening to enclose the electrode assembly within the housing. Two terminals 50 are provided on the top cover 60, and each tab 12 of the bare cell 10 is electrically connected to the corresponding terminal 50 through a corresponding current-conducting plate 20.

[0030] Combination Figure 1 and Figure 2 As can be seen, the two bare cells 10 of the battery cell 100 are basically laid flat before being joined together. After being joined together, the two bare cells 10 are stacked on top of each other and can then be placed into the casing of the battery cell 100. For ease of explanation, the following text will mainly refer to... Figure 1 and Figure 2 The structure of bare cell 10 will be illustrated using the bare cell 10 on the left as an example. The structure of bare cell 10 on the right can be referenced from that on the left, and will not be described again in this article.

[0031] See Figure 1 The bare cell 10 includes a body 11 and tabs 12. As described above, the body 11 can be formed by winding and stacking positive electrode sheets, separators, and negative electrode sheets, or by alternately stacking positive electrode sheets, negative electrode sheets, and separators. In some embodiments, the body 11 is generally rectangular, having intersecting first direction X and second direction Y. In some embodiments, the first direction X can be referred to as the height direction of the body 11, and the second direction Y can be referred to as the length direction of the body 11. The body 11 includes a first end face 111 and a second end face 113 opposite to each other, and a side surface 110 located between the first end face 111 and the second end face 113. The first end face 111 and the second end face 113 are located at both ends of the body 11 along the first direction X. The side surface 110 includes a first side surface 112 and a second side surface 114 opposite to each other, and a third side surface 115 and a fourth side surface 116 opposite to each other. The first side surface 112 and the second side surface 114, due to their larger area, can also be referred to as the large surface of the body 11. The first end face 111 and the second end face 113 can also be referred to as the top and bottom surfaces of the bare cell 10.

[0032] The number of tabs 12 can be set as needed. For example, a bare cell 10 can be configured with two tabs 12, one tab 12 for connection to the positive electrode and the other tab 12 for connection to the negative electrode. In some embodiments, each tab 12 is disposed at a first end face 111 of the body 11 and extends beyond the first end face 111. Each tab 12 also has a certain length in the second direction Y. Each tab 12 includes a first side 1201 and a second side 1202 opposite to each other, the first side 1201 for contacting the current guide plate 20 described below, and the second side 1202 for contacting the insulating protective film 30 described below.

[0033] In some embodiments, each tab 12 includes multiple tab pieces stacked on top of each other. Each tab piece can be attached to a corresponding position on a corresponding positive or negative electrode piece, or each tab piece can be integrally formed with a corresponding positive or negative electrode piece. The tab 12 formed by the multiple tab pieces stacked together (also referred to as a tab bundle) allows the current to flow more evenly within the body 11, avoiding uneven heating caused by excessive local current, thereby affecting the battery life. It can be understood that when it is necessary to combine two bare cells 10, each tab 12 can be bent to approach the corresponding first end face 111, thereby allowing the first side faces 112 of the two bare cells 10 to approach each other.

[0034] The battery cell 100 may also include multiple guide vanes 20 and multiple insulating protective films 30. As an example, two guide vanes 20 are configured, each guide vane 20 being connected to a corresponding terminal (positive or negative terminal) 50, for example, by welding. One of the two guide vanes 20 is used to connect to the tab 12 connected to the positive terminal, and the other guide vane 20 is used to connect to the tab 12 connected to the negative terminal. Each guide vane 20 and its corresponding tab 12 are connected by welding (e.g., ultrasonic welding, laser welding, resistance welding) to achieve an electrical connection between the tab 12 and the corresponding terminal 50.

[0035] Specifically, see Figure 1 and Figure 2 In some embodiments, the tab 12 includes a first welding portion 121, and a guide plate 20 is disposed on a first side 1201 of the tab 12 and includes a second welding portion 221 corresponding to the first welding portion 121. The second welding portion 221 is welded to the first welding portion 121 by means of, for example, ultrasonic welding, laser welding, resistance welding, etc. The first welding portion 121 also corresponds to the solder mark on the tab 12.

[0036] See Figure 1 and Figure 2In some embodiments, each current guide 20 is located between the bare cell 10 on the left and the bare cell 10 on the right, and each current guide 20 is simultaneously connected to the corresponding tab 12 of the bare cell 10 on the left and the corresponding tab 12 of the bare cell 10 on the right.

[0037] See also Figure 1 and Figure 2 Each tab 12 is provided with an insulating protective film 30, which is connected to at least one of the body 11, the tab 12, and the current guide plate 20 via an adhesive layer 40. The insulating protective film 30 mainly serves to cover the tab 12 to provide insulation protection. The adhesive layer 40 serves to fix the position of the insulating protective film 30, preventing significant displacement of the insulating protective film 30 or even detachment from the bare cell 10. In some embodiments, the insulating protective film 30 includes a first insulating portion 301 and a second insulating portion 302. The insulating protective film 30 is, for example, an integral structure, and the material of the insulating protective film 30 may be, for example, but not limited to, PE or PET. The first insulating portion 301 is adapted to cover the second side 1202 of the tab 12. The second insulating portion 302 corresponds to the first end face 111 and the first side face 112 of the body 11. In some embodiments, the adhesive layer 40 is simultaneously disposed on the first insulating portion 301 and the second insulating layer 302.

[0038] Reference Figures 1 to 4 This illustration shows an illustrative embodiment of an adhesive layer 40 disposed on a first insulating portion 301. Specifically, the adhesive layer 40 includes a plurality of first adhesive layers 41 disposed on the first insulating portion 301. The plurality of first adhesive layers 41 are disposed on one side of the first insulating portion 301 facing the second side 1202 of the tab 12. In some embodiments, the first insulating portion 301 is held to cover the tab 12 by being connected to the second side 1202 of the tab 12 through the plurality of first adhesive layers 41. In some embodiments, the first insulating portion 301 is held to cover the tab 12 by being connected to the flow guide 20 through the plurality of first adhesive layers 41. In some embodiments, the first insulating portion 301 is held to cover the tab 12 by being connected to both the second side 1202 of the tab 12 and the flow guide 20 through the plurality of first adhesive layers 41. Each first adhesive layer 41 can be made of a suitable material, and each first adhesive layer 41 can be disposed on the first insulating portion 301 of the insulating protective film 30, for example, by coating.

[0039] In some embodiments, a plurality of first adhesive layers 41 are spaced apart in the second direction Y and avoid the first weld portion 121. In some embodiments, the plurality of first adhesive layers 41 are arranged on both sides of the first weld portion 121 in the second direction Y. In some embodiments, the total thickness of the first insulating portion 301 and the first adhesive layers 41 can be in the range of 30 μm to 100 μm.

[0040] It should be noted that the figures, values, etc., mentioned above and elsewhere in this disclosure are exemplary and are not intended to limit the scope of this disclosure in any way. Any other suitable figures or values ​​are possible.

[0041] Combining the above and Figure 2 It is known that when two bare cells need to be combined, the tab 12 needs to be bent beforehand so that the second side 1202 of the tab 12 is close to the first end face 111 of the body 11. At this time, the first insulating part 301 covering the second side 1202 of the tab 12 plays a role in insulation and protection.

[0042] According to the battery cell 100 provided in this embodiment, the first insulating portion 301 of the insulating protective film 30 covering the second side 1202 of the tab 12 is reliably connected to at least one of the tab 12 and the current guide plate 20 through a plurality of first adhesive layers 41 with high adhesion. Simultaneously, the plurality of first adhesive layers 41 are spaced apart in the second direction Y (the width direction of the bare cell body) and avoid the first welding portion 121 of the tab 12. This effectively prevents the tab 12 (especially the surface tab) from being torn at the solder joint due to the multiple first adhesive layers 41 with high adhesion directly pulling on the first welding portion of the tab 12 during cell expansion or bending. Therefore, the capacity and safety performance of the battery cell 100 can be improved.

[0043] See Figure 1 , Figure 3 and Figure 4 In some embodiments, the first insulating portion 301 includes a first functional area 31 and a plurality of first connection areas 32, wherein the first functional area 31 is located between and connected to the plurality of first connection areas 32. Figure 4 The boundary line between the first functional area and the adjacent first connection area 32 is shown by a dashed line. The portion of the first welding part 121 and the portion of the tab 12 adjacent to the first welding part 121 are covered by the first functional area 31, and multiple first adhesive layers 41 are disposed on multiple first connection areas 32. The first insulating part 301 of the insulating protective film 30 is used to divide the first functional area 31 and multiple first connection areas 32, which facilitates the control of the position of multiple first adhesive layers 41 on the first insulating part 301.

[0044] See Figure 3 In some embodiments, the first insulating portion 301 is rectangular. In the second direction Y, the first functional area 31 includes a rectangular region located at the middle position of the first insulating portion 301, and the plurality of first connecting areas 32 include a plurality of rectangular regions located on both sides of the first functional area 31. Figure 3In the illustrated embodiment, the first insulating portion 301 includes a central first functional region 31 and two first connecting regions 32 located on either side of the first functional region 31. A first adhesive layer 41 is formed on each first connecting region 32, for example, by coating. Of course, in other embodiments, the first functional region 31 and the plurality of first connecting regions 32 may have other implementations beyond the examples described above. The first insulating portion 301 only needs to be able to reliably cover the electrode 12 by being connected to at least one of the tab 12 and the guide plate 20 through the plurality of first adhesive layers 41 disposed on the plurality of first connecting regions 32. For example, in some embodiments, the plurality of first connecting regions 32 may be arranged at at least two corners of the first insulating portion 301, which are spaced apart in the second direction Y, with the non-first connecting region 32 area of ​​the first insulating portion 301 serving as the first functional region 31.

[0045] See back Figure 1 In some embodiments, the first weld portion 121 forms a certain interval d1 with both sides of the first connection area 32 (first adhesive layer 41) in the second direction Y. In some embodiments, d1 ≥ 3 mm. It is understood that in practical applications, the numerical range of d1 is not limited to the examples above.

[0046] In some embodiments, in the first direction X, the edge of the first insulating portion 301 away from the first end face 111 is flush with the edge of the tab 12 away from the first end face 111, or the edge of the first insulating portion 301 away from the first end face 111 extends beyond the edge of the tab 12 away from the first end face 111. In some embodiments, in the first direction X, the distance by which the edge of the first insulating portion 301 away from the first end face 111 extends beyond the edge of the tab 12 away from the first end face 111 is d2. In some embodiments, d2 ranges from 0 to 3 mm. It is understood that in practical applications, the numerical range of d2 is not limited to the examples above.

[0047] In some embodiments, the length d3 of the first connecting region 32 located on either side of the first functional region 31 in the second direction Y is 1mm to 3mm larger than the single-sided misalignment of the tab 12. It is understood that in practical applications, the range of values ​​for the length d3 of the first connecting region 32 located on either side of the first functional region 31 in the second direction Y being larger than the single-sided misalignment of the tab 12 is not limited to the examples described above.

[0048] In some embodiments, in the second direction Y, either side edge of the first insulating portion 301 protrudes relative to the side edge of the adjacent tab 12, and the minimum length of this protrusion is d4. In some embodiments, d4 ranges from 1 mm to 3 mm. It is understood that in practical applications, the numerical range of d4 is not limited to the examples above.

[0049] In some embodiments, the length d6 of the first functional area 31 in the second direction Y is 2mm to 20mm greater than the length of the first welded portion 121 in the second direction Y. It is understood that in practical applications, the numerical range of d6 is not limited to the examples described above.

[0050] See Figure 4 In some embodiments, the first functional area 31 may not have an adhesive layer, which allows for a certain amount of movement between the tab 12 and the first functional area 31, effectively reducing the tensile force from the insulating protective film 30 on the first welded part 121, and further effectively preventing the tab 12 from being torn.

[0051] In some embodiments, the first functional area 31 is transparent. In this case, the first functional area 31 may not have an adhesive layer. The first functional area 31 may be colored or colorless, as long as it has high transparency to facilitate visual inspection. By making the first functional area 31 transparent, the condition of the tab 12 can be judged through the first functional area 31, allowing for visual inspection of locations on the tab 12 that are prone to tearing (such as the first weld 121). This helps prevent defective products with damaged tabs 12 from flowing to the next manufacturing stage, improving the performance reliability and safety reliability of the battery cell.

[0052] In some embodiments, at least a portion of the plurality of first connection areas 32 are provided with first identification color blocks, which facilitate the identification of the adhesive application status of the first insulating portion 301 by a charge-coupled device (CCD) camera or other type of imaging device. In some embodiments, the plurality of first connection areas 32 themselves have colors that can be identified by a CCD camera or other type of imaging device, thus eliminating the need for the process of arranging the first identification color blocks on the plurality of first connection areas 32, thereby reducing manufacturing costs.

[0053] See Figure 5 In some alternative embodiments, the adhesive layer 40 includes not only a plurality of first adhesive layers 41, but also a second adhesive layer 42 disposed on the first functional area 31. Depending on the size of the first insulating portion 301 and the tab 12, the second adhesive layer 42 may be connected at least to the tab 12 and may be selectively connected to the guide plate 20.

[0054] In some embodiments, the material adhesion of the second adhesive layer 42 may be less than that of the first adhesive layer 41. The second adhesive layer 42 can be applied to the first functional area 31 by coating. In some embodiments, the material of the second adhesive layer 42 may be the same as that of the first adhesive layer 41, and the thickness of the second adhesive layer 42 may be less than that of the first adhesive layer 41. In some embodiments, the material adhesion of the second adhesive layer 42 is less than that of the first adhesive layer 41, and the thickness of the second adhesive layer 42 is less than that of the first adhesive layer 41. As a result, the adhesion between the second adhesive layer 42 and the tab 12 is weaker, which can also reduce the tensile force on the first welding part 121 from the first insulating part 301. In addition, the thickness difference between the second adhesive layer 42 and the first adhesive layer 41 can create a visual difference, which also facilitates the identification of the adhesive application status of the insulating protective film 30 by CCD camera equipment or other types of imaging equipment.

[0055] See Figures 1 to 3 as well as Figure 6 In some embodiments, the adhesive layer 40 may further include a third adhesive layer 43 disposed on the second insulating portion 302, the second insulating portion 302 being connected to at least one of the first end face 111 and the first side face 112 via the third adhesive layer 43. Thus, the insulating protective film 30 expands its insulating protection area through the second insulating portion 302. There are many implementations of the third adhesive layer 43, as long as it allows the second insulating portion 302 to be substantially adhered to the area protected by the second insulating portion 302.

[0056] See Figure 3 and Figure 6 In some embodiments, the second insulating portion 302 includes a second functional region 33 and a plurality of second connection regions 34. The second functional region 33 is located between and connected to the plurality of second connection regions 34. Figure 6 The boundary line between the second functional area 33 and the adjacent second connection area 34 is shown by a dashed line. Multiple third adhesive layers 43 are disposed on the second insulating portion 302, and these third adhesive layers 43 are disposed on the multiple second connection areas 34. Dividing the second insulating portion 302 of the insulating protective film 30 into the second functional area 33 and the multiple second connection areas 34 facilitates control over the position of the multiple third adhesive layers 43 on the second insulating portion 302.

[0057] See also Figure 3 and Figure 6 In some embodiments, the second insulating portion 302 is rectangular. In the second direction Y, the second functional region 33 includes a rectangular region located at the middle position of the second insulating portion 302, and the plurality of second connecting regions 34 include a plurality of rectangular regions located on both sides of the second functional region 33. Figure 3In the illustrated embodiment, the second insulating portion 302 includes a central second functional region 33 and two second connecting regions 34 located on either side of the second functional region 33. A third adhesive layer 43 is formed on each second connecting region 34, for example, by coating. Of course, in other embodiments, the second functional region 33 and the plurality of second connecting regions 34 may have other implementations beyond the examples described above. The second insulating portion 302 only needs to be able to connect to the body 11 via the plurality of third adhesive layers 43 disposed on the plurality of second connecting regions 34, so as to substantially adhere to the surface of the body 11 it covers. For example, in some embodiments, the plurality of second connecting regions 34 may be arranged at at least two corners of the second insulating portion 302, the at least two corners being spaced apart in the second direction Y, and the area of ​​the second insulating portion 302 not containing the second connecting regions 34 serving as the second functional region 33.

[0058] In some embodiments, each third adhesive layer 43 may be made of a suitable material, and each third adhesive layer 41 may be applied to the second insulating portion 302 of the insulating protective film 30 by means of coating. The total thickness of the second insulating portion 302 and the third adhesive layer 43 may be in the range of 30 μm to 100 μm.

[0059] See Figure 3 In some embodiments, a plurality of first connection regions 32 and a plurality of second connection regions 34 correspond one-to-one. A plurality of first adhesive layers 41 and a plurality of third adhesive layers 43 correspond one-to-one. In some embodiments, each first adhesive layer 41 may be integrally coated with a corresponding third adhesive layer 43, and the two have the same dimensions in the second direction Y.

[0060] See back Figure 1 and Figure 2 In some embodiments, the second insulating portion 301 extends a predetermined length d5 ​​along the first side surface 112 in the first direction X. In some embodiments, d5 ranges from 5 mm to 20 mm. It is understood that in practical applications, the numerical range of d5 is not limited to the examples above. This allows for a larger adhesive area between the second insulating portion 302 and the first side surface 112, making the insulating protective film 30 less likely to detach from the bare battery cell 10, and the insulating anti-slip film 30 provides a larger insulating protective area for the bare battery cell 10.

[0061] See Figure 6 In some embodiments, the second functional area 33 may not have an adhesive layer, which allows for a certain amount of movement between the first side 112 and the second functional area 33, and can also reduce the tensile force from the insulating protective film 30 on the first welded part 121, further effectively preventing the tab 12 from being torn.

[0062] In some embodiments, the second functional area 33 is transparent. In this case, the second functional area 33 may not have an adhesive layer. The second functional area 33 may be colored or colorless, as long as it has high transparency to facilitate visual detection. In some embodiments, the first functional area 31 and the second functional area 33 have the same dimensions in the second direction Y.

[0063] In some embodiments, at least a portion of the plurality of second connection areas 34 are provided with second identification color blocks, which facilitate the identification of the adhesive application status of the second insulating portion 302 by a charge-coupled device (CCD) camera or other type of imaging device. In some embodiments, the plurality of second connection areas 34 themselves have colors that can be identified by a CCD camera or other type of imaging device, thus eliminating the need for the process of arranging second identification color blocks on the plurality of second connection areas 34, thereby reducing manufacturing costs.

[0064] See Figure 7 In some alternative embodiments, the adhesive layer 40 may further include a fourth adhesive layer 44 disposed on the second functional area 33. The second functional area 33 can be connected to the first end face 111 and the first side face 112 through the fourth adhesive layer 44, further improving the connection strength between the insulating protective film 30 and the bare battery cell 10.

[0065] In some embodiments, the material adhesion of the fourth adhesive layer 44 may be less than that of the third adhesive layer 43. The fourth adhesive layer 44 can be applied to the second functional area 33 by coating. In some embodiments, the material of the fourth adhesive layer 44 may be the same as that of the third adhesive layer 43, and the thickness of the fourth adhesive layer 44 may be less than that of the third adhesive layer 43. In some embodiments, the material adhesion of the fourth adhesive layer 44 is less than that of the third adhesive layer 43, and the thickness of the fourth adhesive layer 44 is less than that of the third adhesive layer 43. In some embodiments, the material of the fourth adhesive layer 44 may be the same as that of the second adhesive layer 42, and the second adhesive layer 42 and the fourth adhesive layer 44 may be integrally coated. This reduces the pulling force exerted on the body 11 and the tab 12 by the second insulating portion 302. Furthermore, the above-described embodiments of the third adhesive layer 43 and the fourth adhesive layer 44 are also easy to implement. Furthermore, the thickness difference between the fourth adhesive layer 44 and the third adhesive layer 43 can create a visual difference, so that CCD camera equipment or other types of imaging equipment can identify the adhesive application status of the second insulating part 302.

[0066] Figure 8 A schematic diagram showing a modified embodiment of the insulating protective film 30 is provided. The structure of the insulating protective film 30 can be referred to the description of the structure of the insulating protective film 30 above. The following text will mainly describe the differences between the two, while the same parts will not be described again.

[0067] See Figure 8 The insulating protective film 30 is rectangular. Two first connecting areas 32 are located at the two corners of the first insulating portion 301 away from the second insulating portion 302, and two second connecting areas 34 are located at the two corners of the second insulating portion 302 away from the first insulating portion 301. In some embodiments, the lengths of each first connecting area 32 and each second connecting area 34 in the second direction Y are equal. In some embodiments, the lengths of each first connecting area 32 and each second connecting area 34 in the second direction Y are at least partially unequal. Identification color blocks may be provided on both the two first connecting areas 32 and the two second connecting areas 34, or the two first connecting areas 32 and the two second connecting areas 34 themselves may have an identifiable color, so that CCD camera devices or other types of imaging devices can identify the adhesive application status of the insulating protective film 30.

[0068] In the second direction Y, at least the first functional area 31 has portions extending to both sides of the first insulating portion 301. This increases the area of ​​the visual detection region of the insulating protective film 30 for determining the state of the tabs.

[0069] In this embodiment, the adhesive layer 40 on the insulating protective film 30 has been optimized. The structure of the insulating protective film 30 itself does not need to be modified. Therefore, there is no need to change the adhesive application mechanism used to apply the insulating protective film 30, which helps to reduce costs.

[0070] It should be noted that although the battery cell 100 described above uses a composite cell as an example, it is understood that in practical applications, the implementation method of the battery cell 100 is not limited to... Figure 1 and Figure 2 The embodiments shown are as follows. For example, in some alternative embodiments, the battery cell may consist of only a single bare cell, which does not need to be combined with other bare cells. Alternatively, in some alternative embodiments, the number of bare cells 10 included in the combined cell of the battery cell 100 is not limited to two.

[0071] Additionally, in some embodiments, the insulating protective film 30 may not include the second insulating portion 302; instead, it may only include the first insulating portion 301 covering the tab 12. In some embodiments, the first insulating portion 301 may only cover the tab 12 without contacting the guide plate 20. These are also within the scope of this disclosure.

[0072] Embodiments of this disclosure also provide a battery pack comprising the battery cells described in the above embodiments.

[0073] The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, and are not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A battery cell (100), characterized in that, include: Bare battery cell (10), including: A body (11) having intersecting first direction (X) and second direction (Y), wherein the body (11) includes a first end face (111) located at one end of the body (11) along the first direction (X); and A tab (12) is disposed on the first end face (111) of the body (11) and extends to the outside of the first end face (111), wherein the tab (12) includes a first side (1201) and a second side (1202) opposite to each other, and the tab (12) further includes a first weld portion (121). A guide vane (20) is disposed on the first side (1201) of the tab (12) and includes a second weld portion (221), the second weld portion (221) being welded to the first weld portion (121); and An insulating protective film (30) includes a first insulating portion (301) covering the second side (1202) of the tab (12), wherein a plurality of first adhesive layers (41) are disposed on the first insulating portion (301), the plurality of first adhesive layers (41) are spaced apart in the second direction (Y) and avoid the first weld portion (121), and the first insulating portion (301) is connected to at least one of the tab (12) and the guide plate (20) through the plurality of first adhesive layers (41).

2. The battery cell (100) according to claim 1, characterized in that, The first insulating portion (301) includes a first functional area (31) and a plurality of first connection areas (32), wherein the first functional area (31) is located between and connected to the plurality of first connection areas (32). The first welding part (121) and the portion of the tab (12) adjacent to the first welding part (121) are covered by the first functional area (31), and the plurality of first adhesive layers (41) are disposed on the plurality of first connection areas (32).

3. The battery cell (100) according to claim 2, characterized in that, The first insulating portion (301) is rectangular, and In the second direction (Y), the first functional area (31) includes a rectangular area located in the middle of the first insulating part (301), and the plurality of first connection areas (32) include a plurality of rectangular areas located on both sides of the first functional area (31).

4. The battery cell (100) according to claim 2, characterized in that, The first insulating portion (301) is rectangular, and the plurality of first connecting areas (32) are located at the plurality of corners of the first insulating portion (301).

5. The battery cell (100) according to claim 2, characterized in that, At least a portion of the plurality of first connection areas (32) are provided with a first identification color block or at least a portion of the plurality of first connection areas (32) have an identification color.

6. The battery cell (100) according to any one of claims 2 to 5, characterized in that, The first functional area (31) is transparent, and / or the first functional area (31) is not provided with an adhesive layer.

7. The battery cell (100) according to any one of claims 2 to 5, characterized in that, The first functional area (31) is provided with a second adhesive layer (42), and Wherein, the material adhesion of the second adhesive layer (42) is less than that of the first adhesive layer (41), and / or, the thickness of the second adhesive layer (42) is less than that of the first adhesive layer (41).

8. The battery cell (100) according to claim 5, characterized in that, The body (11) further includes a second end face (113) and a side face (110), the second end face (113) being opposite to the first end face (111), and the side face (110) being located between the first end face (111) and the second end face (113) and including a first side face (112) and a second side face (114) opposite to each other; and The insulating protective film (30) further includes a second insulating part (302) connected to the first insulating part (301), the second insulating part (302) corresponding to the first end face (111) and the first side face (112), wherein a third adhesive layer (43) is provided on the second insulating part (302), and the second insulating part (302) is connected to at least one of the first end face (111) and the first side face (112) through the third adhesive layer (43).

9. The battery cell (100) according to claim 8, characterized in that, The second insulating portion (302) includes a second functional area (33) and a plurality of second connecting areas (34), wherein the second functional area (33) is located between and connected to the plurality of second connecting areas (34); and The second insulating part (302) is provided with a plurality of the third adhesive layers (43), and the plurality of the third adhesive layers (43) are provided on the plurality of second connection areas (34).

10. The battery cell (100) according to claim 9, characterized in that, The second insulating portion (302) is rectangular, and In the second direction (Y), the second functional area (33) includes a rectangular area located in the middle of the second insulating part (302), and the plurality of second connecting areas (34) include a plurality of rectangular areas located on both sides of the second functional area (33).

11. The battery cell (100) according to claim 10, characterized in that, The plurality of first connection regions (32) and the plurality of second connection regions (34) are connected one-to-one, and The plurality of first adhesive layers (41) are connected one-to-one with the plurality of third adhesive layers (43).

12. The battery cell (100) according to claim 9, characterized in that, The second insulating portion (302) is rectangular, and the plurality of second connecting areas (34) are located at the plurality of corners of the second insulating portion (302).

13. The battery cell (100) according to claim 9, characterized in that, At least a portion of the plurality of second connection areas (34) are provided with a second identification color block or at least a portion of the plurality of second connection areas (34) have an identification color.

14. The battery cell (100) according to claim 9, characterized in that, The second functional area (33) is transparent, and / or the second functional area (33) is not provided with an adhesive layer.

15. The battery cell (100) according to claim 9, characterized in that, The second functional area (33) is provided with a fourth adhesive layer (44), and Wherein, the material adhesion of the fourth adhesive layer (44) is less than that of the third adhesive layer (43), and / or, the thickness of the fourth adhesive layer (44) is less than that of the third adhesive layer (43).

16. A battery pack, characterized in that, Includes a battery cell (100) according to any one of claims 1 to 15.

Images