A battery and battery pack

Abstract

This utility model discloses a battery and a battery pack. The battery includes a cell and a cover plate. The cell includes a body and a tab disposed on the side of the body. The cover plate and the tab are located on the same side of the body. The terminal post in the cover plate is welded to the tab. The battery also includes a first adhesive member, a second adhesive member, and a third adhesive member. The tab has a first surface and a second surface disposed opposite to each other. The first adhesive member is bonded to the first surface, the second adhesive member is bonded to the second surface, and the third adhesive member is bonded to both the second surface and the second adhesive member. The first adhesive member has a first end away from the body, and the second adhesive member has a second end away from the body. There is a first distance between the first end and the second end. Along the direction from the body to the tab, the length of the adhesive portion of the third adhesive member and the second adhesive member is a second distance. The ratio of the second distance to the first distance is 0.1 to 15.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and more particularly to a battery and battery pack. Background Technology

[0002] A battery typically consists of a cell and two cover plates. The positive tab of the cell is welded to the positive terminal of one of the cover plates, and the negative tab of the cell is welded to the negative terminal of the other cover plate. In a prismatic battery, the cell typically has two large faces, two side faces, and two end faces. When the positive and negative tabs of the cell are located on the two side faces respectively, the two cover plates are also located on the two side faces respectively. The cover plate with the positive terminal is located on the same side as the positive tab, and the cover plate with the negative terminal is located on the same side as the negative terminal.

[0003] Both positive and negative tabs consist of multiple stacked sheet-like structures. After each sheet-like structure is folded up, it is welded to the corresponding terminal post. After welding, the cover plate is fastened to the side of the main body. At this time, the tab will bend. If the folding effect of each sheet-like structure is not good, the outermost sheet-like structure will become loose and warped, which will lead to a decrease in battery performance. Utility Model Content

[0004] This utility model provides a battery and battery pack to increase the convergence effect of the sheet-like structures in the tabs, thereby improving the battery performance.

[0005] In a first aspect, this utility model provides a battery, including a battery cell and a cover plate. The battery cell includes: a body and a tab disposed on the side of the body; the cover plate and the tab are located on the same side of the body; the electrode post in the cover plate is welded to the tab.

[0006] The battery also includes a first adhesive member, a second adhesive member, and a third adhesive member. The tabs have a first surface and a second surface that are disposed opposite to each other. The first adhesive member is bonded to the first surface, the second adhesive member is bonded to the second surface, and the third adhesive member is bonded to the second surface and the second adhesive member, respectively.

[0007] The first adhesive member has a first end away from the body, and the second adhesive member has a second end away from the body. There is a first distance between the first end and the second end. Along the direction from the body to the tab, the length of the adhesive portion of the third adhesive member and the second adhesive member is a second distance. The ratio of the second distance to the first distance is 0.1 to 15.

[0008] Secondly, this utility model provides a battery pack, including: a housing and a battery as described in the first aspect above, the battery being disposed within the housing.

[0009] The beneficial effects of this utility model are as follows:

[0010] The present invention provides a battery and battery pack in which, when the first adhesive is bonded to the first surface, the second adhesive is bonded to the second surface, and the third adhesive is bonded to the second surface and the second adhesive respectively, the first adhesive, the second adhesive and the third adhesive can increase the adhesive force on the outermost sheet structure and increase the closing effect of each sheet structure in the tab. Furthermore, the first adhesive member has a first end away from the body, and the second adhesive member has a second end away from the body. There is a first distance between the first end and the second end. Along the direction from the body to the tab, the length of the adhesive portion of the third adhesive member and the second adhesive member is the second distance. If the ratio of the second distance to the first distance is small, it means that the first distance is relatively large and the second distance is relatively small. After the tab is bent, the effect of closing the sheet-like structure on the second surface side of the tab is limited, and loosening and lifting may occur. If the ratio is large, it means that the first distance is relatively small and the second distance is relatively large. After the tab is bent, the effect of closing the sheet-like structure on the first surface side of the tab is limited, and loosening and lifting may occur. Therefore, setting the ratio within 0.1 to 15 can improve the closing effect on the sheet-like structures on both sides, thereby improving the performance of the battery. Attached Figure Description

[0011] Figure 1 This is a three-dimensional structural diagram of a battery provided in an embodiment of the present utility model;

[0012] Figure 2 for Figure 1 A partially enlarged schematic diagram of the end of the battery cell within the dashed box 1 in the diagram;

[0013] Figure 3 For along Figure 2 The cross-sectional view shown by the dashed line x1 in the figure;

[0014] Figure 4 This is a schematic diagram of the battery pack provided in an embodiment of the present utility model.

[0015] Figure label:

[0016] 10-Cell, 11-Body, 12-Taper, 20-Cover plate, 21-Cover plate corresponding to the positive electrode, 22-Cover plate corresponding to the negative electrode, 211-Terminal post, 31-First adhesive component, 32-Second adhesive component, 33-Third adhesive component, 34-Fourth adhesive component, 40-Soldering sheet, 110-Casing, 120-Battery, b1-Side, b2-Large surface, b3-End face, b4-First surface, b5-Second surface, Q0-Soldering area, D1-First end, D2-Second end, D3-Third end, D4-Fourth end, L1-First distance, L2-Second distance, A0-Midpoint, k1-Thickness of the first adhesive component, k2-Thickness of the second adhesive component, k3-Thickness of the third adhesive component, k4-Thickness of the fourth adhesive component. Detailed Implementation

[0017] The specific embodiments of a battery and battery pack provided by this utility model will be described in detail below with reference to the accompanying drawings. It should be noted that the described embodiments are only some embodiments of this utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0018] This utility model embodiment provides a battery, such as Figures 1 to 3 As shown, the battery may include: a battery cell 10 and a cover plate 20. The battery cell 10 includes: a body 11, and a cover plate 20 disposed on the side of the body 11 (e.g., Figure 1 and Figure 2 The electrode lug 12 (shown as side b1 in the diagram); the cover plate 20 and the electrode lug 12 are located on the same side of the body 11; the electrode post 211 in the cover plate 20 is welded to the electrode lug 12; wherein, in order to avoid Figure 2 The structure is too complex and the specific structure of the cover plate 20 is not shown.

[0019] The battery also includes a first adhesive 31, a second adhesive 32, and a third adhesive 33. The tab 12 has a first surface b4 and a second surface b5 disposed opposite to each other. Figure 2 The problem of the middle perspective Figure 2 The second surface b5 is not marked. The first adhesive 31 is bonded to the first surface b4, the second adhesive 32 is bonded to the second surface b5, and the third adhesive 33 is bonded to the second surface b5 and the second adhesive 32 respectively.

[0020] The first adhesive member 31 has a first end D1 away from the body 11, and the second adhesive member 32 has a second end D2 away from the body 11. A first distance L1 exists between the first end D1 and the second end D2. Along the direction from the body 11 to the tab 12, that is, along... Figure 3In the x-direction shown, the length of the adhesive portion of the third adhesive 33 and the second adhesive 32 is the second distance L2; the ratio of the second distance L2 to the first distance L1 can be set to 0.1~15.

[0021] Thus, on the one hand, when the first adhesive 31 is bonded to the first surface b4, the second adhesive 32 is bonded to the second surface b5, and the third adhesive 33 is bonded to the second surface b5 and the second adhesive 32 respectively, the adhesive force on the outermost sheet structure can be increased through the first adhesive 31, the second adhesive 32 and the third adhesive 33, thereby increasing the closing effect of each sheet structure in the tab 12.

[0022] On the other hand, the first adhesive member 31 has a first end D1 away from the body 11, and the second adhesive member 32 has a second end D2 away from the body 11. A first distance L1 exists between the first end D1 and the second end D2. Along the direction from the body 11 to the tab 12, the length of the adhesive portion of the third adhesive member 33 and the second adhesive member 32 is the second distance L2. The ratio of the second distance L2 to the first distance L1 is 0.1 to 15. When the first surface b4 faces the body 11 after the tab 12 is bent, if the ratio is small, it indicates that the first distance L1 is relatively large and the second distance L2 is relatively small. If the ratio is too small, the effect of closing the sheet-like structure on the second surface b5 side of the tab 12 is limited, which may result in loosening and warping. If the ratio is too large, it means that the first distance L1 is relatively small and the second distance L2 is relatively large. In this case, the effect of closing the sheet-like structure on the first surface b4 side of the tab 12 is limited, which may also result in loosening and warping. Of course, the above situation will also occur when the second surface b5 faces the body 11 after the tab 12 is bent. Therefore, setting the ratio within the range of 0.1 to 15 can improve the closing effect on the sheet-like structures on both sides, thereby improving the performance of the battery.

[0023] On the other hand, if the electrode 12 along Figure 3 After the solid arrow x2 in the diagram is bent, the second surface b5 of the tab 12 will face the cover plate 20. At this time, a third adhesive 33 is set on the second surface b5 to prevent the bent tab 12 from contacting the cover plate 20 and causing insulation failure. This ensures the insulation between the tab 12 and the cover plate 20, and improves the manufacturing yield and reliability of the battery.

[0024] Furthermore, the ratio of the second distance L2 to the first distance L1 can be set to 1~10, which can further enhance the gathering effect on the sheet-like structures on both sides, thereby improving the performance of the battery.

[0025] The first distance L1 can be set to 1mm~15mm. This way, when the tab 12 is bent, the tensile force on the first surface b4 and the second surface b5 of the tab 12 is different, making it easier to bend and improving the ease of assembly. The second distance L2 can be set to 1mm~10mm. This way, when the tab 12 is bent, the adhesive force on the sheet-like structure on the second surface b5 side can be increased, increasing its closing effect and thus improving the battery performance.

[0026] Optionally, the battery cell 10 can be a laminated battery cell, which includes multiple positive electrode plates, multiple negative electrode plates, and a separator. Each positive electrode plate and each negative electrode plate is inserted into the separator in a “Z” fold at intervals. In the laminated battery cell 10, the surface with the smallest area and the highest number of layers can be seen. This surface is the end face b3 of the battery cell 10. The surface with the larger area adjacent to the end face b3 of the battery cell 10 is the large surface b2 of the battery cell 10. The surfaces adjacent to the end face b3 and the large surface b2 of the battery cell 10 are the side surfaces b1 of the battery cell 10.

[0027] At this time, each positive electrode has a sheet-like structure on the same side of the cell 10. These sheet-like structures converge and retract to form a positive electrode tab. Correspondingly, the cover plate located on the same side as the positive electrode tab can be called the positive electrode cover plate 21. At this time, the cover plate has a positive electrode post to facilitate the connection between the positive electrode tab and the positive electrode post. Similarly, each negative electrode has a sheet-like structure on the same side of the cell 10. These sheet-like structures converge and retract to form a negative electrode tab. Correspondingly, the cover plate located on the same side as the negative electrode tab can be called the negative electrode cover plate 22. At this time, the cover plate has a negative electrode post to facilitate the connection between the negative electrode tab and the negative electrode post. The electrode tab 12 mentioned in this embodiment can be either a positive electrode tab or a negative electrode tab. Accordingly, the cover plate 20 mentioned in this embodiment is the cover plate 20 located on the same side as the electrode tab 12.

[0028] Optionally, in addition to being bonded to the first surface b4 of the tab 12, the first adhesive 31 can also be bonded to other structures, such as, but not limited to: the first adhesive 31 being bonded to the large surface b2 of the body 11, or the first adhesive 31 being bonded to the side surface b1 of the body 11. This can increase the bonding area between the first adhesive 31 and the battery cell 10, increase the bonding strength, and thus improve the gathering effect on the sheet structure.

[0029] Similarly, in addition to being bonded to the second surface b5 of the tab 12, the second adhesive 32 can also be bonded to other structures, such as, but not limited to: the second adhesive 32 being bonded to the large surface b2 of the body 11, or the second adhesive 32 being bonded to the side surface b1 of the body 11. This can increase the bonding area between the second adhesive 32 and the battery cell 10, increase the bonding strength, and thus improve the gathering effect on the sheet structure.

[0030] Optionally, compared to the second surface b5, the first surface b4 is closer to the midpoint A0 of the side surface b1; compared to the second end D2, the first end D1 is closer to the body 11, such as... Figure 3 As shown. At this time, along the electrode 12 Figure 3 After the solid arrow x2 in the diagram is bent, the first surface b4 will face the body 11, while the second surface b5 will move away from the body 11. This bending provides space for the free end of the tab 12, and also allows for better alignment between the cover plate 20 and the body 11 of the cell 10, resulting in a battery with a more regular shape. The free end of the tab 12 can be considered as the end of the tab 12 that is furthest from the body 11.

[0031] Alternatively, compared to the first surface b4, the second surface b5 is closer to the midpoint A0 of the side surface b1. In this case, compared to the first end D1, the second end D2 is closer to the body 11 (not shown in the diagram). Thus, the tab 12 can move along... Figure 3 The solid arrow x2 in the middle bends in the opposite direction. After bending, the second surface b5 will face the body 11, while the first surface b4 will move away from the body 11. This can also provide space for the free end of the tab 12, and the cover plate 20 and the body 11 of the cell 10 can be better aligned, so that a battery with a relatively regular shape can be obtained.

[0032] Alternatively, if the first surface b4 and the second surface b5 are equally close to the midpoint A0 of the side surface b1, then compared to the second end D2, the first end D1 is closer to the body 11, or the second end D2 is closer to the body 11 (not shown in the diagram). In this case, regardless of whether it is along... Figure 3 The solid arrow in the middle bends twice, or follows... Figure 3 The bends in the opposite direction of the solid arrow x2 in the middle can provide some space for the free end of the accommodating tab 12. However, the space provided will be less than that of the two methods above, but it can still achieve a good folding effect.

[0033] Alternatively, compared to the second surface b5, the first surface b4 is closer to the midpoint A0 of the side surface b1. In this case, compared to the second end D2, the first end D1 is closer to the body 11. (Not shown in the diagram). Thus, along the tab 12... Figure 3 After the solid arrow x2 in the middle is bent, it can also provide some space for the free end of the tab 12. However, the space provided will be less than the two methods above, but it can still achieve a certain shrinking effect.

[0034] Other similar settings are not listed here. Specific settings can be configured according to actual needs to meet the requirements of different scenarios and improve design flexibility.

[0035] Furthermore, the convergence point of the plate-like structures in the tab 12 after being retracted can be located at 1 / 2 of the height direction of the side b1 on which the tab 12 is located. 1 / 2 refers to... Figure 3 Near the location indicated by the dashed line A1 shown in the diagram; or at 1 / 3 of the height of the side b1 where the tab 12 is located, where 1 / 3 refers to... Figure 3 The location may be near the position indicated by the dashed lines A2 or A3 shown in the diagram; or it may be at 1 / 4 of the height of the side b1 where the tab 12 is located, or at 1 / 5 of the height of the side b1 where the tab 12 is located, etc. The specific location can be set according to actual needs, and no specific limitation is made here. It should be understood that the height direction of the side b1 can be considered as... Figure 3 The z-direction is shown in the figure.

[0036] Optionally, when welding the second surface b5 of the tab 12 to the pole post 211, since the third adhesive 33 is located on the second surface b5 of the tab 12, the third adhesive 33 avoids the pole post 211. This can prevent the third adhesive 33 from interfering with the assembly of the pole post 211, thereby ensuring the effective welding of the tab 12 and the pole post 211.

[0037] The avoidance methods include various approaches, such as, but not limited to: the third adhesive member 33 is disposed on the side of the pole post 211 facing the body 11, so that the third adhesive member 33 can be disposed between the body 11 and the pole post 211, for example... Figure 2 and Figure 3 As shown, this way the third adhesive component 33 will not occupy the position of the pole post 211, providing space for the pole post 211 and thus facilitating its assembly. Alternatively, the third adhesive component 33 may have a hollow structure through which the pole post 211 passes (not shown). In this way, the third adhesive component 33 can also provide space for the pole post 211, thus facilitating its assembly.

[0038] Optionally, the battery may also include a fourth adhesive 34, which is bonded to the first surface b4 and the first adhesive 31 respectively; the tab 12 has a solder area Q0, and the fourth adhesive 34 covers the solder area Q0.

[0039] Thus, on the one hand, if the electrode 12 along... Figure 3 After the solid arrow x2 in the figure is bent, the first surface b4 of the tab 12 will face the body 11. At this time, the fourth adhesive 34 is set on the first surface b4 to avoid the bent tab 12 from contacting the body 11 and failing to maintain insulation, thereby improving the manufacturing yield and reliability of the battery.

[0040] On the other hand, the soldering area Q0 can be considered as the area in the tab 12 used for welding with the terminal post 211. Therefore, welding slag may appear in the soldering area Q0 after welding. Since the prior art usually provides an insulating coating in the soldering area Q0, and the insulating coating has a weak covering effect on the welding slag, the welding slag may puncture the insulating coating, leading to a short circuit between the positive tab and the negative electrode in the body 11, or between the negative tab and the positive electrode in the body 11, which would cause a short circuit in the cell 10. In this embodiment of the present invention, when the fourth adhesive 34 is used to replace the insulating coating, the fourth adhesive 34 has a larger thickness and hardness compared to the insulating coating, so it can improve the covering effect on the welding slag, thereby avoiding a short circuit in the cell 10 and improving the reliability of the battery.

[0041] Furthermore, the greater the thickness k4 of the fourth adhesive 34, the better the coverage of welding slag. Therefore, the thickness k4 of the fourth adhesive 34 can be set to 30μm~100μm, thereby improving the reliability of the battery.

[0042] Furthermore, the battery may also include a soldering sheet 40, which is disposed between the tab 12 and the fourth adhesive member 34. That is, the soldering sheet 40 is disposed on the surface of the tab 12 opposite to the terminal post 211, and the soldering sheet 40 covers the soldering area Q0. The melting point of the soldering sheet 40 is lower than the melting point of the tab 12. In other words, the soldering sheet 40 and the terminal post 211 are respectively disposed on opposite sides of the tab 12.

[0043] The reason for setting up the flux pad 40 is as follows: assuming laser welding is used, the laser intensity will increase from 0 to the target value during welding. Without the flux pad 40, the tab 12 will gradually melt through as the laser intensity increases. Since melting through starts locally and slowly spreads to the entire solder area Q0, some locations of the tab 12 may not be melted through. These unmelted locations may result in a cold solder joint, affecting the welding effect between the tab 12 and the electrode post 211. Melting through refers to melting at all locations along the thickness direction of the tab 12.

[0044] If a flux sheet 40 is provided, due to the low melting point of the flux sheet 40, the flux sheet 40 will be gradually melted through as the luminous intensity increases. Because of the low melting point, the flux sheet 40 will also melt more thoroughly, achieving almost complete melting of the entire flux sheet 40. At this time, the melted flux sheet 40 can melt the tabs 12 from various positions, thereby making it easier to melt the tabs 12 of the entire solder area Q0, avoiding cold solder joints and improving the soldering effect.

[0045] It should be understood that if the requirements for the welding effect are high, the flux sheet 40 can completely cover the solder area Q0, so that the tab 12 in the solder area Q0 can be melted through; if the requirements for the welding effect are not very high, but the cost requirements are high, the flux sheet 40 can partially cover the solder area Q0, so as to reduce the volume of the flux sheet 40 and thus reduce the manufacturing cost.

[0046] The flux sheet 40 can be made of a metal with a low melting point, such as, but not limited to, aluminum or copper. The specific material can be set according to actual needs, and no specific limitation is made here.

[0047] Optionally, the third adhesive member 33 has a third end D3 near the body 11, and the fourth adhesive member 34 has a fourth end D4 near the body 11, with the third end D3 and the fourth end D4 flush. Figure 3 The third end D3 and the fourth end D4 shown are located in the plane indicated by the dashed line A4, where the plane indicated by the dashed line A4 is a plane perpendicular to the paper. Figure 3 It's a matter of perspective, so in Figure 3 The plane seen in the image is a line. Alternatively, the third end D3 and the fourth end D4 may not be flush, as not shown in the diagram. In this case, the third end D3 may be closer to the body 11, or the fourth end D4 may be closer to the body 11.

[0048] Optionally, the thickness k1 of the first adhesive component 31, the thickness k2 of the second adhesive component 32, the thickness k3 of the third adhesive component 33, and the thickness k4 of the fourth adhesive component 34 can be set to be the same. This allows four adhesive components to be cut from one raw material, reducing the types of raw materials and thus helping to reduce the manufacturing cost of the battery.

[0049] Optionally, the materials used to make the first adhesive component 31, the second adhesive component 32, the third adhesive component 33, and the fourth adhesive component 34 may be the same or different. The material used to make any one of the first adhesive component 31, the second adhesive component 32, the third adhesive component 33, and the fourth adhesive component 34 may be a material with insulating and adhesive properties, such as, but not limited to, insulating tape.

[0050] Based on the same inventive concept, this utility model embodiment also provides a battery pack, such as... Figure 4 As shown, the battery pack may include: a housing 110 and a battery 120 as described in any of the embodiments above, wherein the battery 120 is disposed within the housing 110.

[0051] The battery 110 can be configured in multiple ways, and each battery can be connected in series, parallel or a combination of series and parallel to meet the performance requirements of the battery pack.

[0052] Of course, in addition to the battery 110 and the housing 120, the battery pack may also include other structures for realizing the functions of the battery pack, such as, but not limited to, battery management devices. The specific configuration can be set according to actual needs, and no specific limitation is made here.

[0053] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. A battery, characterized in that, The device includes a battery cell and a cover plate. The battery cell includes a body and a tab disposed on the side of the body. The cover plate and the tab are located on the same side of the body. The electrode post in the cover plate is welded to the tab. The battery further includes a first adhesive component, a second adhesive component, and a third adhesive component. The tab has a first surface and a second surface disposed opposite to each other. The first adhesive component is bonded to the first surface, the second adhesive component is bonded to the second surface, and the third adhesive component is bonded to both the second surface and the second adhesive component. The first adhesive member has a first end away from the body, the second adhesive member has a second end away from the body, and there is a first distance between the first end and the second end; along the direction from the body to the tab, the length of the adhesive portion of the third adhesive member and the second adhesive member is a second distance; the ratio of the second distance to the first distance is 0.1 to 15.

2. The battery as described in claim 1, characterized in that, The ratio of the second distance to the first distance is 1 to 10.

3. The battery as described in claim 1, characterized in that, The first distance is 1mm to 15mm.

4. The battery as described in claim 1, characterized in that, The second distance is 1mm to 10mm.

5. The battery as described in claim 1, characterized in that, Compared to the second surface, the first surface is closer to the midpoint of the side surface; Compared to the second end, the first end is closer to the body.

6. The battery as claimed in claim 1, characterized in that, The second surface of the electrode tab is welded to the electrode post, and the third adhesive member avoids the electrode post.

7. The battery according to any one of claims 1-6, characterized in that, The battery further includes a fourth adhesive component, which is bonded to the first surface and the first adhesive component respectively; The electrode tab has a solder mark area, and the fourth adhesive component covers the solder mark area.

8. The battery as claimed in claim 7, characterized in that, The battery also includes a soldering sheet disposed between the tab and the fourth adhesive component, the soldering sheet covering the soldering area, and the melting point of the soldering sheet being lower than that of the tab.

9. The battery as described in claim 7, characterized in that, The first adhesive, the second adhesive, the third adhesive, and the fourth adhesive have the same thickness.

10. A battery pack, characterized in that, include: The housing and the battery as described in any one of claims 1-9, wherein the battery is disposed within the housing.

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