Battery core structure
By adding an insulating layer at the current collector tab of the battery cell, the short circuit problem caused by the difference in current collector area is solved, and the safe and reliable stacking of battery cells is achieved.
Patent Information
- Application Number
- CN202422842494.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Priority Date
- 2023-12-04
- Filing Date
- 2024-11-21
- Publication Date
- 2025-11-25
- Estimated Expiration
- 2034-11-21
AI Technical Summary
When existing battery cells have unequal current collector layer areas, the tabs are prone to misalignment due to compression and tolerance, which can cause short circuit risks, especially when a high number of cells are stacked in parallel.
An insulating layer is added to the back of the tab of the smaller collector layer and the end face of the larger collector layer to form an L-shaped configuration, in order to avoid short circuits caused by contact between the tab and the collector layer.
This effectively reduces the potential short-circuit risk during battery cell assembly caused by differences in current collector layer area, ensuring that battery cells do not short-circuit even when misaligned.
Smart Images
Figure CN223598735U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a battery core structure, especially for the case that the areas of two current collecting layers are not equal, an insulating layer is additionally provided to avoid the risk of potential short circuit of the stacked battery core. BACKGROUND
[0002] In response to the booming development of the new energy vehicle market, as one of the three core technologies of new energy electric vehicles, the structural protection design and thermal management planning of power batteries are considered as an important part of new energy electric vehicles. At the same time, in order to improve the endurance of new energy electric vehicles, the demand for lightweight and high energy density is an inevitable trend.
[0003] In order to achieve sufficient power and capacity, the common method is to stack the battery core. Please refer to Figure 1A 、 1B The battery core 10 is composed of a first current collecting layer 11, a first active material layer 12, a separation layer 13, a second active material layer 14 and a second current collecting layer 15 stacked in sequence. The first and second current collecting layers 11 and 15 extend out of the first and second tabs 111 and 151, respectively, at opposite ends of the battery core 10. As shown in Figure 1A 、 1B , the common parallel stacking is stacked by contacting the current collecting layers with the same polarity (first current collecting layer 11). In practice, the areas of the two current collecting layers will have slight differences. Therefore, the inner side of the first and second tabs 111 and 151 is generally provided with an insulating layer 112, 152, that is, the side close to the first and second active material layers 12 and 14, to avoid short circuit when the first and second tabs 111 and 151 are assembled and contact the adjacent first and second current collecting layers 11 and 15, respectively.
[0004] However, the first tab 111' after stacking may be exposed due to factors such as extrusion and tolerance, as shown in Figure 2A 、 2B At this time, when the misaligned first tab 111' is bent, it may contact the edge of the second current collecting layer 15 with a larger area, causing a short circuit.
[0005] Based on the above-mentioned shortcomings of the prior art, the utility model provides a battery core structure to effectively solve the above-mentioned problems. UTILITY MODEL CONTENTS
[0006] The utility model discloses a battery core structure, the insulating layer is additionally arranged on the back of the pole lug of the current collecting layer of small area and the end surface of the current collecting layer of large area, and the risk of potential short circuit caused by the area difference of the first and second current collecting layers during the assembly of the battery core is greatly reduced.
[0007] The utility model provides a battery core structure, contain first current collecting layer, first active material layer, isolation layer, second active material layer and second current collecting layer who stacks in proper order, first current collecting layer has first pole lug, second current collecting layer has second pole lug, the characteristics of this battery core structure are:
[0008] The first current collecting layer and second current collecting layer have opposite first surface and second surface and opposite first side and second side respectively, the first pole lug extends outward from the first side of the first current collecting layer, the second pole lug extends outward from the first side of the second current collecting layer, and the first surface of the first current collecting layer is stacked with the second surface of the second current collecting layer, wherein the area of the first current collecting layer is slightly smaller than the area of the second current collecting layer, and the two side edges of the intersection of the second surface of the first current collecting layer and the first pole lug have an insulating layer.
[0009] As preferred, the insulating layer is located at the two side edges of the intersection of the first pole lug and the second surface of the first current collecting layer, and extends to the top edge of the second surface of the first current collecting layer adjacent to the first side, forming an L-shaped configuration.
[0010] As preferred, the width of the second surface of the first current collecting layer is 3-7mm.
[0011] As preferred, the height of the second surface of the first current collecting layer is 0.5-1.5mm.
[0012] As preferred, the width of the first pole lug is at least 1.5mm.
[0013] As preferred, the height of the first pole lug is 2.5-8.5mm.
[0014] As preferred, the second side of the second current collecting layer has an insulating layer.
[0015] In another aspect, the utility model provides a battery core structure, contain the first current collecting layer, first active material layer, isolation layer, second active material layer and second current collecting layer who stacks in proper order, first current collecting layer has first lug, second current collecting layer has second lug, first current collecting layer and second current collecting layer have opposite first surface and second surface respectively, and opposite first side and second side, first lug extends outward from the first side of first current collecting layer, second lug extends outward from the first side of second current collecting layer, and the first surface of first current collecting layer is stacked with the second surface of second current collecting layer, wherein the area of first current collecting layer is slightly smaller than the area of second current collecting layer, and the second side of second current collecting layer has insulating layer.
[0016] The following is explained in detail through specific embodiments, when more easily understand the purpose, technical content, characteristics and the effect achieved of the utility model. BRIEF DESCRIPTION OF DRAWINGS
[0017] Figure 1A 、 1B It is the stacking schematic diagram of prior art battery core structure.
[0018] Figure 2A 、 2B It is the short circuit schematic diagram of misalignment of prior art stacked battery core structure.
[0019] Figure 3 It is the exploded schematic diagram of battery core structure of the utility model.
[0020] Figure 4A 、 4B It is the schematic diagram of battery core structure of the utility model.
[0021] Figure 5 It is the side view of battery core structure of the utility model.
[0022] Figure 6A 、 6B It is the schematic diagram of different embodiments of insulating layer of battery core structure of the utility model.
[0023] Figure 7A 、 7B It is the parallel stacking schematic diagram of battery core structure of the utility model.
[0024] Figure 8A It is the lug bending schematic diagram of battery core structure of the utility model.
[0025] Figure 8B It is the misalignment schematic diagram of battery core structure of the utility model.
[0026] REFERENCE NUMERALS
[0027] 10 battery core
[0028] 11 first current collector layer
[0029] 111 first tab
[0030] 111’ first tab
[0031] 112 insulating layer
[0032] 12 first active material layer
[0033] 13 separation layer
[0034] 14 second active material layer
[0035] 15 second current collector layer
[0036] 151 second tab
[0037] 152 insulating layer
[0038] 21 first current collector layer
[0039] 211 first surface
[0040] 212 second surface
[0041] 213 first side edge
[0042] 214 second side edge
[0043] 215 first tab
[0044] 2151 insulating layer
[0045] 22 first active material layer
[0046] 221 frame adhesive
[0047] 23 separation layer
[0048] 24 second active material layer
[0049] 241 frame adhesive
[0050] 25 second current collector layer
[0051] 251 first surface
[0052] 252 second surface
[0053] 253 first side edge
[0054] 254 second side edge
[0055] 255 second tab
[0056] 2551 insulating layer
[0057] 41 insulating layer
[0058] 42 insulating layer
[0059] L1 height
[0060] L2 height
[0061] W1 width
[0062] W2 width DETAILED DESCRIPTION
[0063] In order to make the advantages, spirit and characteristics of the utility model more easily understood, subsequent will be with example and refer to the described figure carries on the detailed description and discussion. It is declared that these examples are only the representative examples of the utility model, and do not limit the implementation state of the utility model and the request scope of the utility model to only be limited to these example state. The purpose of providing these examples is only to make the disclosure of the utility model more thorough and easy to understand.
[0064] The terms used in the various embodiments disclosed by the utility model are only for the purpose of describing specific embodiments, and not to limit the various embodiments disclosed by the utility model. Unless there is a clear indication, the singular form also includes the plural form. Unless otherwise limited, all terms (including technical terms and scientific terms) used in the specification have the same meaning as the ordinary skill in the art to which the various embodiments disclosed by the utility model belong. The above-mentioned terms (such as the terms defined in the general use dictionary) will be interpreted as having the same meaning as the context meaning in the same technical field, and will not be interpreted as having an idealized meaning or an overly formal meaning, unless clearly limited in the various embodiments disclosed by the utility model.
[0065] The battery core structure disclosed by the utility model, please refer to Figure 3, the first current collecting layer 21 has a first surface 211 and a second surface 212, a first side edge 213 and a second side edge 214, the second current collecting layer 25 also has a first surface 251 and a second surface 252, a first side edge 253 and a second side edge 254, and the first side edge 213 of the first current collecting layer 21 extends a first tab 215, and the first side edge 253 of the second current collecting layer 25 extends a second tab 255. The first current collecting layer 21, the first active material layer 22, the isolation layer 23, the second active material layer 24 and the second current collecting layer 25 are sequentially stacked to form a battery core structure, specifically, the first surface 211 of the first current collecting layer 21 is stacked with respect to the second surface 252 of the second current collecting layer 25, and the first active material layer 22, the isolation layer 23 and the second active material layer 24 are sequentially sandwiched therebetween, and the outer periphery of the first active material layer 22 and the second active material layer 24 is surrounded by a frame glue 221, 241 to achieve the purposes of insulation and packaging.
[0066] Please also refer to Figure 3 、 4A , 4B, the first tab 215 on the first surface 211 of the first current collecting layer 21 (i.e. towards the inside), the bottom of the intersection between the first tab 215 and the first current collecting layer 21 has an insulating layer 2151, similarly, the second tab 255 on the second surface 252 of the second current collecting layer 25 (i.e. towards the inside), the bottom of the intersection between the second tab 255 and the second current collecting layer 25 has an insulating layer 2551, to avoid the contact between the assembled first tab 215 and the second tab 255 and the current collecting layers of different polarities (the second current collecting layer 25 and the first current collecting layer 21) causing short circuit.
[0067] On the other hand, the area of the first current collecting layer 21 is slightly smaller than the area of the second current collecting layer 25, therefore, as shown in the side view Figure 5 , it can be seen that the position of the second current collecting layer 25 will be slightly protruding; for example, as shown in the figure, the first current collecting layer 21 is marked as positive, and the second current collecting layer 25 is marked as negative, that is, the area of the positive current collecting layer will be slightly smaller than the area of the negative current collecting layer, but this part is only for illustration and is not intended to limit that only the area of the positive current collecting layer can be slightly smaller than the area of the negative current collecting layer, in practice, the design can also be that the area of the negative current collecting layer can be slightly smaller than the area of the positive current collecting layer.
[0068] Considering the short circuit problem caused by misalignment due to high stacking number, tolerance, extrusion and other factors after stacking of the battery core of the prior art as described above, the battery core structure of the present application has an insulating layer 41 (seeFigure 6A ) or is provided with an insulating layer 42 on the second side edge 254 of the second current collecting layer 25 (see Figure 6B ), or is provided with both insulating layers 41, 42 (see Figure 4A ) so that it will not be short-circuited even after contact, which will be described later.
[0069] First, please refer to Figure 6A , when considering short-circuiting due to misalignment, the back side of the first current collecting layer 21 (that is, the second surface 212) will be exposed, therefore, the insulating layer 41 is provided on both side edges of the intersection of the second surface 212 of the first current collecting layer 21 and the first tab 215; the insulating layer 41 is located on both side edges of the intersection of the first tab 215 and the second surface 212 of the first current collecting layer 21, and extends to the top edge of the second surface 212 of the first current collecting layer 21 adjacent to the first side edge 213, forming two L-shaped configurations. In terms of size, the width W1 of the second surface 212 of the first current collecting layer 21 is 3-7 mm, the height L1 of the second surface 212 of the first current collecting layer 21 is 0.5-1.5 mm, the width W2 of the first tab 215 is at least 1.5 mm, and the height L2 of the first tab 215 is 2.5-8.5 mm.
[0070] Next, please refer to Figure 6B , considering that the second current collecting layer 25 is larger in area than the first current collecting layer 21, so that its end surface is higher than the position of the first current collecting layer 21 and is easy to contact, the insulating layer 42 can also be provided on the second side edge 254 of the second current collecting layer 25.
[0071] When actually applied in parallel connection, please refer to Figure 7A , the battery cell structure is stacked in contact with each other in the manner that the second surfaces 212 of the first current collecting layers 21 are in contact with each other, after the two battery cell structures are stacked, as shown in Figure 7B , the first surfaces 251 of the second current collecting layers 25 located on the outside are used to stack in contact with each other, forming a stack of two battery cell structures, and thus sequentially stacking the required number of battery cell structures. After stacking is completed, please refer to Figure 8A , the first tabs 215 are welded to form parallel connection of the overall battery cell, and the second tabs 255 (see Figure 7B ) on the other end are the same, which will not be described again. At this time, as shown in Figure 8A , 8B , even if the back surface of the first tab 215 (the side of the second surface 212) is exposed due to misalignment, because of the provision of the insulating layers 41, 42, the short-circuiting phenomenon of the first tab 215 contacting the end surface (the second side edge 254) of the second current collecting layer 25 after being bent can still be avoided.
[0072] In summary, the utility model provides a kind of battery core structure, considering the short circuit problem caused by dislocation caused by high stack quantity, tolerance, extrusion and other factors, the position that may potentially contact short circuit in dislocation is the two side edges of the junction of the first tab of the first current collecting layer with the first current collecting layer outside, or the end surface (second side) of the second current collecting layer with larger area, an insulating layer is additionally provided, which is different from the insulating layer provided on the bottom edge of the tab in the inward direction in the prior art to prevent internal short circuit of single battery core, the newly added insulating layer is used to prevent short circuit phenomenon caused by tab bending after stacking between battery cores.
[0073] The above is only a preferred embodiment of the utility model, and is not intended to limit the scope of the utility model. The scope of protection of the utility model is defined by the claims. Those skilled in the art can make various modifications or equivalent replacements to the utility model within the spirit and protection scope of the utility model, and such modifications or equivalent replacements shall also be considered to fall within the protection scope of the utility model.
Claims
1. A battery cell structure, characterized in that, The battery cell structure comprises a first current collector layer, a first active material layer, an insulating layer, a second active material layer, and a second current collector layer stacked sequentially. The first current collector layer has a first tab, and the second current collector layer has a second tab. The battery cell structure is characterized in that: The first collector layer and the second collector layer each have a first surface and a second surface opposite to each other, and a first side and a second side opposite to each other. The first electrode extends outward from the first side of the first collector layer, and the second electrode extends outward from the first side of the second collector layer. The first surface of the first collector layer is stacked relative to the second surface of the second collector layer. The area of the first collector layer is slightly smaller than the area of the second collector layer. An insulating layer is provided on both sides of the junction between the second surface of the first collector layer and the first electrode.
2. The battery cell structure according to claim 1, characterized in that, The insulating layer is located at the two sides of the junction of the first electrode and the second surface of the first collector layer, and extends to the top edge of the second surface of the first collector layer adjacent to the first side, forming an L-shaped configuration.
3. The battery cell structure according to claim 2, characterized in that, The width of the insulating layer on the second surface of the first collector layer is 3-7 mm.
4. The battery cell structure according to claim 2, characterized in that, The insulating layer is located at a height of 0.5-1.5 mm on the second surface of the first collector layer.
5. The battery cell structure according to claim 2, characterized in that, The insulating layer is located at a width of at least 1.5 mm at the first electrode tab.
6. The battery cell structure according to claim 2, characterized in that, The insulating layer is located at a height of 2.5-8.5 mm at the first electrode tab.
7. The battery cell structure according to any one of claims 1 to 6, characterized in that, The second side of the second collector layer has an insulating layer.
8. A battery cell structure comprising a first current collector layer, a first active material layer, a separator layer, a second active material layer, and a second current collector layer stacked sequentially, wherein the first current collector layer has a first tab and the second current collector layer has a second tab, characterized in that: The first collector layer and the second collector layer each have a first surface and a second surface opposite to each other, and a first side and a second side opposite to each other. The first electrode extends outward from the first side of the first collector layer, and the second electrode extends outward from the first side of the second collector layer. The first surface of the first collector layer is stacked relative to the second surface of the second collector layer. The area of the first collector layer is slightly smaller than the area of the second collector layer, and an insulating layer is provided on the second side of the second collector layer.