Battery cell structure
By adding insulation layers on the contact terminals and end surfaces of battery cell electrode current collecting layers, the battery cell structure effectively mitigates the risk of short circuits caused by surface area mismatches, enhancing the reliability and safety of battery cell stacks.
Patent Information
- Application Number
- FR2024013452
- Authority / Receiving Office
- FR · FR
- Patent Type
- Utility models
- Current Assignee / Owner
- Priority Date
- 2023-12-04
- Filing Date
- 2024-12-04
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2034-12-04
AI Technical Summary
In stacked battery cells, the risk of short circuits arises due to differences in the surface areas of electrode current collecting layers, especially when these layers are not perfectly aligned, leading to potential contact between conductive terminals and larger electrode surfaces during assembly or stacking.
The battery cell structure incorporates insulation layers on the back side of the electrically conductive contact terminal of the smaller-area electrode current collecting layer and on the end surface of the larger-area electrode current collecting layer, forming an L-shaped configuration to prevent short circuits.
This configuration significantly reduces the risk of short circuits during battery cell assembly and stacking, even when there are mismatches in surface areas or when conductive terminals are bent, thereby enhancing the reliability and safety of battery cell stacks.
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
Title of the invention: Battery cell structure Field of invention
[0001] The present invention relates to a battery cell structure and, in particular, to a battery cell structure in which an insulation layer is added in order to avoid the risk of a short circuit in stacked battery cells when the areas of two electrode current collecting layers are not equal. Prior art
[0002] In response to the explosion of the new energy vehicle market, power batteries have been developed as one of the three core technologies of new energy vehicles. Therefore, the structure protection design and thermal management design of power batteries are considered a very important part of new energy vehicles. Meanwhile, lightweight structures and an increase in energy density are inevitable trends to improve the battery life of new energy vehicles.
[0003] To obtain sufficient power and sufficient capacity, it is common to stack battery cells. Referring to Figures 1A and 1B, each battery cell 10 consists of a first electrode current collecting layer 11, a first active material layer 12, a separation layer 13, a second active material layer 14, and a second electrode current collecting layer 15, which are successively stacked. A first electrically conductive contact terminal 111 and a second electrically conductive contact terminal 151 extend respectively from a first electrode collecting layer 11 and a second electrode collecting layer 15, which are provided at the two opposite ends of the corresponding battery cell 10.As shown in Figures 1A and 1B, this is a usual stack of battery cells connected in parallel, in which electrode current collecting layers of the same polarity (the first electrode current collecting layers 11) are in contact with each other. In practice, the surfaces of two electrode current collecting layers differ slightly. Therefore, two insulation layers 112, 152 are generally applied on the inner sides of the corresponding first electrically conductive contact terminal 111 or the corresponding second electrically conductive contact terminal 151, namely on the side close to the corresponding first active material layer 12 and the corresponding second active material layer 14, in order to prevent, when assembling a first electrically conductive contact terminal 111 and a second terminal . electrically conductive contact layer 151, they do not respectively come into contact with the first adjacent electrode current collecting layer 11 and the second adjacent electrode current collecting layer 15, which could result in a possible short circuit.
[0004] However, in the case of large stacked battery cells or in the case of battery cells connected in parallel in large numbers, it often happens that the back side of a respective first electrically conductive contact terminal 111' is exposed due to crushing, tolerance and other factors (see Figures 2A and 2B). In this case, if this offset first electrically conductive contact terminal 111' is bent, it may come into contact with the edge of the second electrode collector layer 15, which has a larger surface area, which may result in a short circuit.
[0005] The invention aims to effectively solve the above-mentioned problems and to provide a battery cell structure. Objective of the invention
[0006] The main objective of the present invention is to provide a battery cell structure in which an insulation layer is added on the back side of an electrically conductive contact terminal of an electrode current collecting layer having a smaller surface area and on the end surface of an electrically conductive contact terminal of an electrode current collecting layer having a larger surface area, in order to greatly reduce the risk of short circuit existing during battery cell assembly due to the difference in surface area between the first and second electrode current collecting layers.
[0007] The present invention relates to a battery cell structure, comprising a first electrode current collecting layer, a first active material layer, a separation layer, a second active material layer and a second electrode current collecting layer, which are successively stacked, the first electrode current collecting layer having a first electrically conductive contact terminal, the second electrode current collecting layer having a second electrically conductive contact terminal, characterized in that the first electrode current collecting layer and the second electrode current collecting layer each have a first surface and a second surface opposite thereto, as well as a first side and a second side opposite thereto,the first electrically conductive contact terminal extends outwardly from the first side of the first electrode current collecting layer, the second electrically conductive contact terminal extends outwardly from the first side of the second electrode current collecting layer and, for the stack, the first surface of the first collecting layer, electrode current collector layer is disposed opposite the second surface of the second electrode current collector layer, the surface area of the first electrode current collector layer being smaller than the surface area of the second electrode current collector layer and an insulation layer being disposed on each of both sides of the junction between the second surface of the first electrode current collector layer and the first electrically conductive contact terminal.
[0008] An insulation layer may be located on each of the two sides of the junction between the first electrically conductive contact terminal and the second surface of the first electrode current collecting layer and extend toward the upper, respectively lower, edge, near the first side, of the second surface of the first electrode current collecting layer, to form an L-shaped configuration.
[0009] According to various particular embodiments: • the width of the insulation layer located on the second surface of the first electrode current collecting layer may be in the range of 3 to 7 mm; and / or • the height of the insulation layer located on the second surface of the first electrode current collecting layer may be in the range of 0.5 to 1.5 mm; and / or • the width of the insulation layer located on the first electrically conductive contact terminal may be at least 1.5 mm; and / or • the height of the insulation layer located on the first electrically conductive contact terminal may be in the range of 2.5 to 8.5 mm; and / or • an insulation layer may be provided on the second side of the second electrode current collecting layer.
[0010] The present invention also relates to a battery cell structure, comprising a first electrode current collecting layer, a first active material layer, a separation layer, a second active material layer and a second electrode current collecting layer, which are stacked successively, the first electrode current collecting layer having a first electrically conductive contact terminal, the second electrode current collecting layer having a second electrically conductive contact terminal, characterized in that the first electrode current collecting layer and the second electrode current collecting layer each have a first surface and a second surface opposite thereto, as well as a first side and a second side opposite thereto,the first electrically conductive contact terminal extends outwardly from the first side of the first layer, electrode current collector, the second electrically conductive contact terminal extends outward from the first side of the second electrode current collector layer and, for stacking, the first surface of the first electrode current collector layer is arranged opposite the second surface of the second electrode current collector layer, the surface area of the first electrode current collector layer being smaller than the surface area of the second electrode current collector layer and an insulation layer being arranged on the second side of the second electrode current collector layer.
[0011] In order to better understand the objectives, technical content, characteristics and advantageous effects of the present invention, concrete embodiment examples are described in detail below. Brief description of the drawings
[0012]
[0013] [Fig.1A] is an exploded perspective schematic view of a conventional battery cell structure in which the battery cells are stacked;
[0014] [Fig.lB] is a partial schematic sectional view of a conventional battery cell structure in which the battery cells are stacked;
[0015] [Fig.2A] is a schematic view of the conventional battery cell structure, in which in battery cells a short circuit is caused by an offset;
[0016] [Fig.2B] is a schematic view of the conventional battery cell structure, in which in battery cells a short circuit is caused by an offset;
[0017] [Fig.3] is a schematic exploded view of the battery cell structure according to the invention;
[0018] [Fig.4A] is a schematic view of the battery cell structure according to the invention;
[0019] [Fig.4B] is a schematic view of the battery cell structure according to the invention;
[0020] [Fig.5] is a side view of the battery cell structure according to the invention;
[0021] [Fig. 6A] is a schematic view of an exemplary embodiment of the insulation layer of the battery cell structure according to the invention;
[0022] [Fig. 6B] is a schematic view of an exemplary embodiment of the insulation layer of the battery cell structure according to the invention;
[0023] [Fig.7A] is a schematic view of the battery cell structure according to the invention, in which the battery cells connected in parallel are stacked;
[0024] [Fig.7B] is a schematic view of the battery cell structure according to the invention, in which the battery cells connected in parallel are stacked;
[0025] [Fig.8A] is a schematic view of the battery cell structure according to the invention, in which the electrically conductive contact terminals are bent;
[0026] [Fig.8B] is a schematic view of the battery cell structure according to the invention, in which an offset occurs during stacking. Detailed description of the exemplary embodiments
[0027] In order to better understand the advantages, nature and characteristics of the present invention, exemplary embodiments are described in detail below with reference to the accompanying drawings. The present invention is described with reference to specific exemplary embodiments and with reference to specific drawings, but the invention is not limited thereto. These exemplary embodiments are provided only for the purpose of making the present disclosure more thorough and easier to understand.
[0028] The terminology used herein is intended only to describe the specific exemplary embodiments and is not intended to limit the general idea of the invention. As used herein, the singular forms "a," "an" and "the" shall also include the plural forms, unless the context clearly indicates otherwise. Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as that assigned to them by a person of ordinary skill in the art to which the exemplary embodiments pertain. It should also be noted that terms, for example those defined in commonly used dictionaries, are to be interpreted as having the meaning consistent with their meaning in the context of the relevant art, and not in an idealized or overly formal sense, unless expressly defined herein.
[0029] Reference is made to [Fig. 3] which shows a battery cell structure according to the invention. The battery cell structure comprises a first electrode current collecting layer 21, a first active material layer 22, a separation layer 23, a second active material layer 24 and a second electrode current collecting layer 25, the first electrode current collecting layer 21 having a first surface 211 and a corresponding second surface 212 and a first side 213 and a corresponding second side 214, and the second electrode current collecting layer 25 also having a first surface 251 and a corresponding second surface 252 and a first side 253 and a corresponding second side 254, a first contact terminal electrically conductive 215 extending from the first side 213 of the first electrode current collecting layer 21 and a second electrically conductive contact terminal 255 extending from the first side 253 of the second electrode current collecting layer 25, the first electrode current collecting layer 21, the first active material layer 22, the separation layer 23, the second active material layer 24 and the second electrode current collecting layer 25 being successively stacked to form a battery cell structure.More specifically, for stacking, the first surface 211 of the first electrode current collecting layer 21 is arranged opposite the second surface 252 of the second electrode current collecting layer 25, the first active material layer 22, the separation layer 23 and the second active material layer 24 being successively clamped together, and the outer peripheries of the first active material layer 22 and the second active material layer 24 being surrounded by frame adhesives 221 and 241 respectively to achieve the purpose of insulation and encapsulation.
[0030] Referring to Figures 3, 4A and 4B, for the first electrically conductive contact terminal 215, an insulation layer 2151 is provided at the lower end of the junction between the first electrically conductive contact terminal 215 and the first electrode current collecting layer 21, on the side of the first surface 211 of the first electrode current collecting layer 21 (i.e., toward the inner side). Similarly, for the second electrically conductive contact terminal 255, an insulation layer 2551 is provided at the lower end of the junction between the second electrically conductive contact terminal 255 and the second electrode current collecting layer 25, on the side of the second surface 252 of the second electrode current collecting layer 25 (i.e., toward the inner side).In this way, it is possible to avoid a short circuit caused by contact between the first electrically conductive contact terminal 215 or the second electrically conductive contact terminal 255 and the electrode current collecting layer of different polarity (the second electrode current collecting layer 25 or the first electrode current collecting layer 21).
[0031] Furthermore, the surface area of the first electrode current collecting layer 21 is slightly smaller than the surface area of the second electrode current collecting layer 25. Therefore, the side view shown in [Fig. 5] shows that the second electrode current collecting layer 25 slightly protrudes from its position. As shown in the Figures, the first electrode current collecting layer 21 is, for example, identified as a positive electrode and the second electrode current collecting layer 25 as a negative electrode, i.e., the surface area of the positive electrode current collecting layer is slightly less than the area of the negative electrode current collecting layer. However, this is for illustrative purposes only and should not be interpreted as a restriction that the area of the positive electrode current collecting layer must be slightly less than the area of the negative electrode current collecting layer. In practice, the area of the negative electrode collecting layer may also be slightly less than the area of the positive electrode collecting layer.
[0032] In view of the short circuit problem existing in the prior art, which is caused by a mismatch due to factors such as the high stacking amount, tolerance, crushing, etc. after the battery cells are stacked, in the battery cell structure according to the invention, an insulation layer 41 is provided on each of the two sides of the junction between the second surface 212 of the first electrode current collecting layer 21 and the first electrically conductive contact terminal 215 (see [Fig. 6A]) or an insulation layer 42 is provided on the second side 254 of the second electrode current collecting layer 25 (see [Fig. 6B]) or two insulation layers 41, 42 are provided simultaneously (see [Fig. 4A]), so that a short circuit does not occur after contact. This part will be described in detail later.
[0033] Referring to [Fig. 6A], since the back side (i.e., the second surface 212) of the first electrode current collecting layer 21 is exposed during a short circuit caused by an offset, an insulation layer 41 is provided on each of the two sides of the junction between the second surface 212 of the first electrode current collecting layer 21 and the first electrically conductive contact terminal 215. An insulation layer 41 is provided on each of the two sides of the junction between the first electrically conductive contact terminal 215 and the second surface 212 of the first electrode current collecting layer 21 and extends to the second surface 212 of the first electrode current collecting layer 21 and is adjacent to the upper edge of the first side 213 to form an L-shaped configuration.In terms of size, the width W1 on the second surface 212 of the first electrode current collecting layer 21 is in the range of 3 mm to 7 mm, the height L1 on the second surface 212 of the first electrode current collecting layer 21 is in the range of 0.5 mm to 1.5 mm, the width W2 on the first electrically conductive contact terminal 215 is at least 1.5 mm, and the height L2 on the first electrically conductive contact terminal 215 is in the range of 2.5 mm to 8.5 mm.
[0034] Referring now to [Fig. 6B]. Since the surface area of the second electrode current collecting layer 25 is larger than that of the first electrode current collecting layer 21, its end face is higher than the position of the first electrode current collecting layer 21 and is therefore more easily accessible. Therefore, an insulation layer 42 may also be placed on the second side 254 of the second electrode current collecting layer 25.
[0035] Reference will be made to [Fig. 7A]. In the case of the actual parallel connection, the second surfaces 212 of the first electrode current collecting layers 21 are brought into contact with each other when stacking two battery cell structures. Reference will now be made to [Fig. 7B]. After the two battery cell structures have been stacked, the first surfaces 251 of the second electrode current collecting layers 25 located outside are then used for stacking to form a stack of two battery cell structures. In this way, battery cells can be stacked successively in sufficient number to form a battery unit. Reference will now be made to [Fig. 8A]. After the stacking is completed, the first electrically conductive contact terminals 215 are soldered to form a parallel connection throughout the battery unit.A second electrically conductive contact terminal 255 (see [Fig.7B]) located at the other end also functions in the same manner and is therefore not described again here. In this case, as shown in Figures 8A and 8B, the back side (the side of the second surface 212) of a respective first electrically conductive contact terminal 215 is exposed. The arrangement of the insulation layers 41, 42 nevertheless makes it possible to avoid a short circuit that would normally be caused by contact of a respective folded first electrically conductive contact terminal 215 with the end face (the second side 254) of the corresponding second electrode current collecting layer 25.
[0036] In summary, the present invention provides a battery cell structure. In view of the problem of short circuit caused by mismatch due to factors such as high stacking amount, tolerance, crushing, etc., the present invention further provides an insulation layer at the position where mismatch could result in possible contact short circuit, namely on two sides of the junction between the first electrically conductive contact terminal of the smaller-area first electrode current collector layer and the outer side of the first electrode current collector layer or on the end face (on the second side) of the larger-area second electrode current collector layer.Unlike the conventional insulation layer, which is provided on the lower edge of an electrically conductive contact terminal in order to prevent an internal short circuit of a single battery cell, the present invention can prevent a . short circuit caused by bent electrically conductive contact terminals, after stacking of the battery cells, thanks to the added insulation layers.
[0037] The above description represents only preferred examples of the invention and should not limit the scope of the invention. All equivalent changes and all equivalent modifications which, in accordance with the description and the drawings of the invention, can be made by a person skilled in the art of this field, fall within the scope of protection of the present invention. List of reference signs
[0038]
[0039]
[0040]
[0041]
[0042]
[0043]
[0044]
[0045]
[0046]
[0047]
[0048]
[0049]
[0050]
[0051]
[0052]
[0053]
[0054]
[0055] 10 Battery cell 11 First electrode current collecting layer 111 First electrically conductive contact terminal 111' First electrically conductive contact terminal 112 Insulation layer 12 First active material layer 13 Layer ofseparation 14 Second active material layer 15 Second electrode current collecting layer 151 Second electrically conductive contact terminal 152 Insulation layer 21 First electrode current collecting layer 211 First surface 212 Second surface 213 First side 214 Second side 215 First electrically conductive contact terminal 2151 Insulation layer
[0056]
[0057]
[0058]
[0059]
[0060]
[0061]
[0062]
[0063]
[0064]
[0065] 22 First active material layer 221 Frame adhesive 23 Separation layer 24 Second active material layer 241 Frame adhesive 25 Second electrode current collecting layer 251 First surface 252 Second surface 253 First side 254 Second side
[0066] 255 Second electrically conductive contact terminal 2551 Insulation layer
[0067]
[0068]
[0069]
[0070]
[0071]
[0072] 41 Insulation layer 42 Insulation layer L1 Height L2 Height W1 Width W2 Width
Claims
Claims
1. A battery cell structure, comprising a first electrode current collecting layer (21), a first active material layer (22), a separation layer (23), a second active material layer (24) and a second electrode current collecting layer (25), which are stacked successively, the first electrode current collecting layer (21) having a first electrically conductive contact terminal (215) and the second electrode current collecting layer (25) having a second electrically conductive contact terminal (255), characterized in that the first electrode current collecting layer (21) and the second electrode current collecting layer (25) each have a first surface (211; 251) and a second surface (212; 252) opposite thereto, and a first side (213; 253) and a second side (214; 254) opposite thereto,the first electrically conductive contact terminal (215) extends outward from the first side (213) of the first electrode current collecting layer (21), the second electrically conductive contact terminal (255) extends outward from the first side (253) of the second electrode current collecting layer (25), and for stacking, the first surface (211) of the first electrode current collecting layer (21) is arranged opposite the second surface (252) of the second electrode current collecting layer (25), the surface area of the first electrode current collecting layer (21) being smaller than the surface area of the second electrode current collecting layer (25), and an insulation layer (41) is arranged on each of the two sides of the junction between the second surface (212) of the first electrode current collecting layer (21) and the first contact terminal electrically conductive (215).,
2. Battery cell structure according to claim 1, characterized in that an insulation layer (41) is located on each of the two sides of the junction between the first electrically conductive contact terminal (215) and the second surface (212) of the first electrode current collector layer (21) and extends towards the upper, respectively lower edge, close to the first side (213), of the second surface (212) of the first collector layer electrode current (21), to form an L-shaped configuration.
3. A battery cell structure according to claim 2, characterized in that the width (Wl) of the insulation layer (41) located on the second surface (212) of the first electrode current collecting layer (21) is in the range of 3 to 7 mm.
4. A battery cell structure according to claim 2, characterized in that the height (L1) of the insulation layer (41) located on the second surface (212) of the first electrode current collecting layer (21) is in the range of 0.5 to 1.5 mm.
5. Battery cell structure according to claim 2, characterized in that the width (W2) of the insulation layer (41) located on the first electrically conductive contact terminal (215) is at least 1.5 mm.
6. Battery cell structure according to claim 2, characterized in that the height (L2) of the insulation layer (41) located on the first electrically conductive contact terminal (215) is in the range of 2.5 to 8.5 mm.
7. Battery cell structure according to one of claims 1 to 6, characterized in that an insulation layer (42) is provided on the second side (254) of the second electrode current collecting layer (25).
8. A battery cell structure, comprising a first electrode current collecting layer (21), a first active material layer (22), a separation layer (23), a second active material layer (24) and a second electrode current collecting layer (25), which are stacked successively, the first electrode current collecting layer (21) having a first electrically conductive contact terminal (215) and the second electrode current collecting layer (25) having a second electrically conductive contact terminal (255), characterized in that the first electrode current collecting layer (21) and the second electrode current collecting layer (25) each have a first surface (211; 251) and a second surface (212; 252) opposite thereto and a first side (213; 253) and a second side (214;254) opposite thereto, the first electrically conductive contact terminal (215) extends outwardly from the first side (213) thereof; electrode current collecting layer (21), the second electrically conductive contact terminal (235) extends outward from the first side (253) of the second electrode current collecting layer (25), and for stacking, the first surface (211) of the first electrode current collecting layer (21) is arranged opposite the second surface (252) of the second electrode current collecting layer (25), the surface area of the first electrode current collecting layer (21) being smaller than the surface area of the second electrode current collecting layer (25), and an insulation layer (42) being arranged on the second side (254) of the second electrode current collecting layer (25).