Battery cell and battery
By designing the false ear as a folding setting, the battery energy density reduction problem caused by the protrusion of the false ear is solved, and a higher energy density is achieved.
Patent Information
- Application Number
- CN202421311707.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-07
- Publication Date
- 2025-07-04
- Estimated Expiration
- 2034-06-07
AI Technical Summary
In the prior art, the false ear is arranged on the end surface of the wound cell, causing the battery to waste the space in the case in the length direction and affect the energy density of the battery.
The false ear is designed as a folding setting to reduce its length in the length direction and allow its projection area to fall into the end surface of the battery cell, thus freeing up more space for accommodating the battery body and increasing the energy density of the battery.
Through the design of folding false ears, the space occupied by the battery in the thickness direction is reduced and the energy density of the battery is improved.
Smart Images
Figure CN223066411U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of new energy, in particular to an electric core and a battery. Background Art
[0002] In a wound electric core, a plurality of dummy tabs and at least one real tab are arranged on a pole piece. After winding, the dummy tabs are stacked together to shorten the moving distance of current from different circles to the real tab during the charge and discharge process of the electric core, thereby reducing the impedance of the current.
[0003] However, in the prior art, since the dummy tabs protrude from the end face of the wound electric core, a certain amount of space inside the shell will be wasted in the length direction of the battery, thereby affecting the energy density of the battery. Summary of the Utility Model
[0004] The utility model aims to solve at least one of the technical problems existing in the prior art. For this purpose, the utility model provides an electric core capable of reducing the size of the dummy tab in the length direction, thereby improving the energy density of the battery.
[0005] The utility model also provides a battery having the above-mentioned electric core.
[0006] The electric core according to the first aspect embodiment of the utility model includes:
[0007] A main body, the main body includes a first pole piece and a second pole piece, the main body is formed by winding the first pole piece and the second pole piece, the main body has a first end face and a second end face oppositely arranged in a first direction, the first pole piece has a plurality of bending parts and a plurality of straight parts from inside to outside, the bending parts and the straight parts are arranged alternately, each straight part is connected with a first dummy tab, and after winding, the first dummy tabs are stacked to form a conductive member, and the conductive member protrudes from the first end face;
[0008] At least one first tab, the first tab is connected to the first pole piece and protrudes from the first end face or the second end face;
[0009] Wherein, the conductive member is folded towards the main body, and in the projection along the first direction, the projection area of the conductive member on the first end face falls within the first end face.
[0010] The electric core according to the embodiment of the utility model has at least the following beneficial effects:
[0011] In the present application, the first conductive member is folded towards the main body. More specifically, the first conductive member is folded along the thickness direction of the battery cell main body, so as to reduce the length of the first conductive member along the first direction, thereby creating more space for accommodating the battery cell main body and further improving the energy density of the battery. Moreover, after folding, in the projection along the first direction, the projection area of the first conductive member on the first end face falls within the first end face, that is, the length of the folded first conductive member along the thickness direction of the battery cell main body is less than the thickness of the battery cell main body, so as not to protrude from the side surface of the battery cell main body and avoid occupying the space along the thickness direction inside the battery case.
[0012] According to some embodiments of the present invention, the conductive member includes a first conductive member and a second conductive member. The first false tab ears of adjacent layers are arranged staggeredly, and some of the first false tab ears are stacked to form the first conductive member, and the remaining first false tab ears are stacked to form the second conductive member.
[0013] According to some embodiments of the present invention, the first false tab ears of adjacent layers are arranged correspondingly. It is set that each of the first false tab ears is stacked to form the first conductive member, and each of the straight portions is further connected with a second false tab ear. Along the length direction of the first electrode tab, the first false tab ears and the second false tab ears are arranged alternately, and after winding, each of the second false tab ears is stacked to form the second conductive member.
[0014] According to some embodiments of the present invention, both the first conductive member and the second conductive member are bent in the same direction, or the first conductive member and the second conductive member are bent in opposite directions.
[0015] According to some embodiments of the present invention, the directions in which the second conductive member and the first conductive member protrude from the main body are the same.
[0016] According to some embodiments of the present invention, it is set that the first false tab ear and the second false tab ear connected by the same straight portion are a group, and the distances between the first false tab ears and the second false tab ears of each group are equal.
[0017] According to some embodiments of the present invention, the main body further includes a first surface and a second surface arranged in parallel along the thickness direction. The first conductive member is bent towards the first surface, and along the direction from the second surface to the first surface, the lengths of the first false tab ears in the first conductive member gradually decrease.
[0018] According to some embodiments of the present invention, the battery cell further includes at least one second tab ear, the second tab ear is connected to the second electrode tab, and moreover, the second tab ear and the first tab ear both protrude from the second end face.
[0019] According to some embodiments of the present utility model, along the winding direction of the first pole piece, the first pole piece successively has a head end and a tail end, the first pole ear is connected to the first pole piece at the head end, or the first pole ear is connected to the first pole piece at the tail end, or the first pole ear is connected to the first pole piece in a region between the head end and the tail end.
[0020] According to some embodiments of the present utility model, the first conductive member is bonded to the main body.
[0021] The battery according to the second aspect embodiment of the present utility model includes the battery cell described in any one of the above embodiments.
[0022] The additional aspects and advantages of the present utility model will be partly given in the following description, partly become obvious from the following description, or be understood through the practice of the present utility model. Description of the Drawings
[0023] The following further describes the present utility model in conjunction with the drawings and embodiments, where:
[0024] Figure 1 is a schematic structural diagram of the battery cell according to the embodiment of the present utility model;
[0025] Figure 2 is a simplified schematic diagram after the battery cell according to the embodiment of the present utility model is wound and formed;
[0026] Figure 3 is a schematic structural diagram of the pole piece in the unfolded state according to the embodiment of the present utility model;
[0027] Figure 4 is Figure 2 an enlarged schematic diagram of area A in
[0028] Reference Signs:
[0029] Main body 100; First conductive member 101; Second conductive member 102; First surface 103; Arc section 104; Straight section 105; First end face 106;
[0030] First pole piece 110; Bending part 111; Straight part 112; First false pole ear 113; Second false pole ear 114; Head end 115; Tail end 116; Second pole piece 120;
[0031] First pole ear 200; Second pole ear 250. Detailed Embodiments
[0032] Embodiments of the present utility model will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present utility model and should not be construed as a limitation to the present utility model.
[0033] In the description of the present utility model, it should be understood that for the orientation description, such as the orientation or positional relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model.
[0034] In the description of the present utility model, the meaning of several is more than one, and the meaning of multiple is more than two. Understandings such as greater than, less than, exceeding, etc. do not include the present number, and understandings such as above, below, within, etc. include the present number. If there is a description of first and second, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.
[0035] In the description of the present utility model, unless otherwise clearly defined, words such as setting, installing, connecting, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in the present utility model in combination with the specific content of the technical solution.
[0036] In the description of the present utility model, the description referring to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.
[0037] In a wound battery cell, a plurality of dummy tabs and at least one real tab are provided on the electrode tab. After winding, the dummy tabs are stacked together to shorten the moving distance of the current from different layers to the real tab during the charge and discharge process of the battery cell, thereby reducing the impedance of the current.
[0038] However, in the prior art, since the dummy tabs protrude from the end face of the wound battery cell, a certain amount of internal space of the shell will be wasted in the length direction of the battery, thereby affecting the energy density of the battery.
[0039] To solve the above problems, the present application proposes a battery cell, which includes a main body 100 and at least one first tab 200. The main body 100 includes a first electrode plate 110 and a second electrode plate 120. The first electrode plate 110, the separator, and the second electrode plate 120 are wound to form the main body 100 of the battery cell. As shown in Figure 1 In the illustrated embodiment, the main body 100 is runway-shaped and has arc segments 104 on both sides in the width direction of the main body 100. The two arc segments 104 are connected by a straight segment 105. The main body 100 of the battery cell has a first end face 106 and a second end face arranged oppositely in the first direction. The first end face 106 and the second end face are also the two end faces of the main body 100 in the length direction.
[0040] It should be understood that, as shown in Figure 2 and Figure 3 Before winding, both the first electrode plate 110 and the second electrode plate 120 are strip-shaped structures, having a winding head end 115 and a tail end 116. When winding, it starts from the head end 115 and winds up at the tail end 116 to form a winding structure. After winding to form the main body 100, the first electrode plate 110 has a plurality of bending portions 111 and a plurality of straight portions 112 from the inside to the outside. The bending portions 111 and the straight portions 112 are arranged alternately. The stacked bending portions 111 form the arc segments 104 of the main body 100, and the stacked straight portions 112 form the straight segment 105 of the main body 100. Before winding, the lengths of the respective bending portions 111 and the respective straight portions 112 can be determined by calculation.
[0041] Each straight portion 112 is at least connected to a first dummy tab 113. After winding, the first dummy tabs 113 are stacked to form a conductive member, and the conductive member protrudes from the first end face. Specifically, depending on the different positions of the first dummy tabs 113 on the first electrode plate 110, the stacking of the first dummy tabs 113 after winding the first electrode plate 110 presents the following two situations.
[0042] In some embodiments, during the winding process, the first dummy tabs 113 of adjacent layers are correspondingly arranged, so that after winding, the respective first tabs 200 are stacked together, and then are formed into a whole by connection methods such as welding and bonding. For the convenience of subsequent description, the aforementioned whole is named the first conductive member 101. It can be understood that since the first dummy tabs 113 protrude from the first electrode plate 110, the first conductive member 101 after winding and stacking protrudes from the first end face 106 of the main body 100. In the embodiment shown in Figure 3 , a second dummy tab 114 is also provided. In other embodiments, a third dummy tab, a fourth dummy tab, etc. can also be provided. It should be understood that the structures and lengths of the first dummy tab 113 and the second dummy tab 114 can be similar or dissimilar.
[0043] In some other embodiments, during the winding process, the first dummy tabs 113 of adjacent layers are staggered, so that after winding, some of the first dummy tabs 113 are stacked to form the first conductive member 101, and the remaining first dummy tabs 113 are stacked to form the second conductive member 102, thereby reducing the thickness of a single conductive member.
[0044] One end of the first tab 200 is connected to the first electrode tab 110, and the other end is used to connect to the terminal on the battery cover, so as to input or output current. As Figure 1 and Figure 3 shown, the first tab 200 and the first dummy tab 113 are respectively arranged on different sides of the electrode tab along its width direction. After winding to form the battery cell, the first tab 200 and the first conductive member 101 are respectively located at different ends of the main body 100. That is, the first conductive member 101 protrudes from the first end face 106, and the first tab 200 protrudes from the second end face. Thus, during the manufacturing process of the first electrode tab 110, when die-cutting the edge of the first electrode tab 110 to form the first dummy tab 113, the die-cutting spacing and size are relatively uniform, so the die-cutting process is relatively simple. In some other ways, the first tab 200 can also be arranged on the second end face, so as to be on the same end face as the first conductive member 101.
[0045] Taking the first tab 200 connected to the head end 115 of the first electrode tab 110 as an example, when the battery cell outputs current, if there is no first dummy tab 113, the current at the tail end 116 of the first electrode tab 110 needs to flow through the entire first electrode tab 110 until it is output from the first tab 200 located at the head end 115, so the impedance of the battery is relatively high. In the present application, because there is a first dummy tab 113 and it is stacked to form the first conductive member 101, the current in both the inner circle and the outer circle can be directly transported to the layer where the first tab 200 is located through the first conductive member 101, thus greatly shortening the current transmission path and reducing the impedance of the battery.
[0046] It should be noted that since the first conductive part protrudes from the first end face 106, if it is not processed, the first conductive part extends along the first direction, which will occupy more space inside the battery case, resulting in less space for accommodating the main body 100, so the energy density of the battery is relatively low. In the present application, as Figure 2 and Figure 4 shown, the first conductive member 101 is folded towards the main body 100. More specifically, the first conductive member 101 is folded along the thickness direction of the main body 100, so as to reduce the length of the first conductive member 101 along the first direction, thereby creating more space for accommodating the main body 100 of the battery cell to further improve the energy density of the battery.
[0047] Moreover, after folding, in the projection along the first direction, the projection area of the first conductive member 101 on the first end face 106 falls within the first end face 106. That is, the length of the first conductive member 101 along the thickness direction of the main body 100 of the battery cell is less than the thickness of the main body 100 of the battery cell, so as not to protrude from the side surface of the main body 100, thereby avoiding occupying the space in the battery housing along the thickness direction.
[0048] In some embodiments, as Figures 1 to 3 shown, each straight portion 112 is further connected with a second dummy tab 114. In the unfolded state of the first tab 200 (i.e., the state before winding), along the length direction of the first electrode tab 110, the first dummy tab 113 and the second dummy tab 114 are alternately arranged. It should be noted that after winding, the second dummy tabs 114 are stacked to form a second conductive member 102, and the first conductive member 101 and the second conductive member 102 are arranged at intervals. Thus, both the first conductive member 101 and the second conductive member 102 can play a role in shortening the current transmission path.
[0049] Furthermore, the first conductive member 101 and the second conductive member 102 are both bent in the same direction. Taking the embodiments as Figure 1 and Figure 2 shown as an example, the first conductive member 101 and the second conductive member 102 are both bent upward, and the bent first conductive member 101 and second conductive member 102 do not protrude from the upper surface of the main body 100 of the battery cell. Alternatively, the first conductive member 101 and the second conductive member 102 can also be both bent downward. It can be understood that the same bending direction of the first conductive member 101 and the second conductive member 102 is beneficial to improving the consistency of the process flow. In some further embodiments, the folding of the first conductive member 101 and the second conductive member 102 can be simultaneously achieved by the same folding mechanism.
[0050] In other embodiments, the first conductive member 101 and the second conductive member 102 can also be bent in opposite directions. For example, one of the conductive members is bent upward and the other is bent downward.
[0051] Based on the foregoing embodiments, the first conductive member 101 and the first tab 200 are respectively located at both ends of the main body 100, and the first conductive member 101 is located on the first end face 106. Preferably, as Figures 1 to 3 shown, the second conductive member 102 is also arranged on the first end face 106. That is, in the unfolded state of the first electrode tab 110, the first dummy tab 113 and the second dummy tab 114 are arranged on the same side of the first electrode tab 110. Since the structures and arrangement positions of the first dummy tab 113 and the second dummy tab 114 are relatively regular, the process of die-cutting and forming the first dummy tab 113 and the second dummy tab 114 is relatively simple, avoiding the interference of the first tab 200.
[0052] In some embodiments, as Figure 3 shown, the first dummy tab 113 and the second dummy tab 114 connected to the same straight portion 112 are set as a group, that is, the first dummy tab 113 and the second dummy tab 114 provided on the same straight portion 112 are set as a group. It can be understood that a first dummy tab 113 and a second dummy tab 114 are provided on each straight portion 112, and the distances between the first dummy tab 113 and the second dummy tab 114 in each group are equal. It can be understood that since the circumference gradually increases when winding from the inside to the outside, the arc lengths of the bent portions 111 in different circles are not equal, and the lengths of the straight portions 112 are equal. The first dummy tab 113 and the second dummy tab 114 are in the same position on each straight portion 112, so that every time one turn is wound, the first dummy tab 113 of this straight portion 112 can be stacked with the first dummy tab 113 of the inner circle, and the second dummy tab 114 is the same.
[0053] In some embodiments, the main body 100 further includes a first surface 103 and a second surface that are arranged in parallel in the thickness direction. In the embodiment as Figure 2 shown, the first surface 103 is the upper surface, and the second surface is the lower surface. In some other embodiments, the first surface 103 can also be the lower surface, and the second surface is the upper surface. The first conductive member 101 is bent toward the first surface 103, and the second conductive member 102 is also bent toward the first surface 103. Among them, along the direction from the second surface to the first surface 103, the lengths of the first dummy tabs 113 in the first conductive member 101 gradually decrease.
[0054] It can be understood that taking the embodiment as Figure 4 shown as an example, if the lengths of the first dummy tabs 113 in the first conductive member 101 are the same, the first dummy tab 113 at the uppermost end is most likely to protrude from the first surface 103 of the main body 100 during the upward bending process. Along the direction from top to bottom, the probability of each first dummy tab 113 exposing from the first surface 103 gradually decreases. Therefore, in the embodiment as Figure 4 shown, setting the lengths of the first dummy tabs 113 to be different can reduce the risk that the first dummy tab 113 at the uppermost end exposes from the first surface 103 after bending, and avoid occupying the space of the battery in the width direction additionally. It should be noted that the length of the lowermost first dummy tab 113 in the width direction after bending should not be greater than the width of the main body 100.
[0055] In some embodiments, the battery cell further includes at least one second tab 250, and the second tab 250 is connected to the second electrode plate 120. It can be understood that the number of the first tabs 200 and the second tabs 250 can be one or more, and can be adjusted according to specific design requirements. In the embodiment as Figures 1 to 3In the illustrated embodiment, for the convenience of connecting to the terminal post of the housing, the first tab 200 and the second tab 250 both protrude from the second end face. Thus, the terminal post can also be disposed on the same end face of the battery housing corresponding to the second end face, which is beneficial to the connection with the external circuit. Alternatively, the first tab 200 and the second tab 250 both protrude from the first end face to ensure that the first tab 200 and the second tab 250 are disposed at the same position.
[0056] It should be noted that a dummy tab structure similar to that of the first tab 110 can also be provided on the second tab 120 to shorten the current transmission path on the second tab 120. The structure of the second tab 120 can be similar to that of the first tab 110 and will not be described in detail herein.
[0057] In some embodiments, the first tab 200 is connected to the head end 115 of the first tab 110. In other embodiments, the first tab 200 is connected to the tail end 116 of the first tab 110. In still other embodiments, the first tab 200 is connected to the middle of the first tab 110, that is, the region between the head end 115 and the tail end 116. The second tab 250 can also be connected to the head end 115, the tail end 116 or the middle of the second tab 120. It can be understood that along the thickness direction of the main body 100 of the battery cell, the first tab 200 and the second tab 250 need to be staggeredly arranged to prevent the first tab 200 and the second tab 250 from being electrically conducted to cause a short circuit.
[0058] In some embodiments, the first conductive member 101 needs to be bonded to the main body 100 after being bent. It can be understood that taking the first conductive member 101 bent upward as shown in Figure 4 as an example, since the first dummy tabs 113 in the first conductive member 101 have been welded together to form an integral structure, the adhesive can be applied to the inner side of the first conductive member 101 close to the first end face 106 after being bent to connect the first conductive member 101 to the main body 100 and prevent the first conductive member 101 from rebounding after being bent. Alternatively, an adhesive tape can also be attached to the outer side of the first conductive member 101 far from the first end face 106 after being bent to connect with the main body 100 through the adhesive tape.
[0059] In the second aspect of the embodiments of the present application, a battery is proposed, and the battery includes the battery cell mentioned in any one of the above embodiments.
[0060] The above has described the embodiments of the present invention in detail with reference to the drawings. However, the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the scope of knowledge possessed by those of ordinary skill in the art. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.
Claims
1. An electric cell, characterized in that, Comprising: A main body, the main body includes a first pole piece and a second pole piece, the main body is formed by winding the first pole piece and the second pole piece, the main body has a first end face and a second end face oppositely arranged in a first direction, the first pole piece has a plurality of bending parts and a plurality of straight parts from inside to outside, the bending parts and the straight parts are arranged alternately, each of the straight parts is connected with a first dummy tab, after winding, the first dummy tabs are stacked to form a conductive member, and the conductive member protrudes from the first end face; At least one first tab, the first tab is connected to the first pole piece and protrudes from the first end face or the second end face; Wherein, the conductive member is folded towards the main body, and in the projection along the first direction, the projection area of the conductive member on the first end face falls within the first end face.
2. The battery cell according to claim 1, characterized in that, The conductive member includes a first conductive member and a second conductive member, the first dummy tabs of adjacent layers are arranged staggeredly, part of the first dummy tabs are stacked to form the first conductive member, and the remaining first dummy tabs are stacked to form the second conductive member.
3. The battery cell according to claim 1, characterized in that, The first dummy tabs of adjacent layers are arranged correspondingly. Assuming that each of the first dummy tabs is stacked to form a first conductive member, each of the straight parts is further connected with a second dummy tab. Along the length direction of the first pole piece, the first dummy tabs and the second dummy tabs are arranged alternately. After winding, each of the second dummy tabs is stacked to form a second conductive member.
4. The battery cell according to claim 3, wherein, The first conductive member and the second conductive member are both bent in the same direction, or the first conductive member and the second conductive member are bent in opposite directions.
5. The battery cell according to claim 3, wherein, The second conductive member and the first conductive member are both arranged on the first end face.
6. The battery cell according to claim 3, wherein, Assuming that the first dummy tab and the second dummy tab connected to the same straight part are a group, the distances between the first dummy tabs and the second dummy tabs of each group are equal.
7. The battery cell according to claim 1, characterized in that The main body further includes a first surface and a second surface arranged in parallel in the thickness direction. The conductive member is bent towards the first surface. Along the direction from the second surface to the first surface, the lengths of the first dummy tabs in the conductive member gradually decrease.
8. The battery cell according to claim 1, wherein The battery cell further includes at least one second tab, the second tab is connected to the second pole piece, and the directions in which the second tab and the first tab protrude from the main body are the same.
9. The battery cell according to claim 1, wherein, Along the winding direction of the first pole piece, the first pole piece sequentially has a head end and a tail end. The first tab is connected to the first pole piece at the head end, or the first tab is connected to the first pole piece at the tail end, or the first tab is connected to the first pole piece in a region between the head end and the tail end.
10. The battery cell according to claim 1, characterized in that, The conductive member is bonded to the main body.
11. Battery, characterized in that, Including the battery cell according to any one of claims 1 to 10.