Battery

Abstract

The utility model relates to the technical field of batteries, and discloses a battery which comprises a packaging shell, a battery cell and two tabs, and an accommodating space is arranged in the packaging shell; the battery cell is arranged in the accommodating space; the two tabs are electrically connected to the battery cell and extend out of the packaging shell after being hermetically connected with the packaging shell; wherein at least one of the two tabs comprises at least one elastic bending part, and the elastic bending part is positioned in the accommodating space and is configured to extend when being stretched and / or shorten when being compressed; one of the two tabs is a positive tab, and the other tab is a negative tab, so that the problem that the stress at the connecting position of the tabs and the battery cell is increased can be solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field, concretely relates to a battery. BACKGROUND

[0002] With the continuous development of battery technology field, the requirement of battery is also higher and higher.

[0003] At present, battery is faced with big test in the self-weight impact performance of falling, roller and the like, when battery is subjected to impact or falling and the like, the electric core is easy to move in the packaging shell, thereby increasing the stress of the connecting position of the tab and the electric core, and the tab and the electric core are easy to separate or tear. SUMMARY

[0004] The utility model discloses at least one of the technical problems in the prior art is solved. To this end, the utility model provides a battery, which can improve the problem of increased stress of the connecting position of the tab and the electric core.

[0005] The battery according to the utility model embodiment comprises a packaging shell, an electric core and two tabs, the packaging shell is provided with a containing space; the electric core is arranged in the containing space; the two tabs are electrically connected to the electric core and extend outward from the packaging shell after being sealingly connected to the packaging shell; wherein at least one of the two tabs comprises at least one elastic bending part, the elastic bending part is located in the containing space and is configured to elongate when being stretched and / or shorten when being compressed; one of the two tabs is a positive tab, and the other is a negative tab.

[0006] The battery according to the utility model embodiment has at least the following beneficial effects: the battery of the embodiment is provided with at least one tab comprising at least one elastic bending part, and the elastic bending part is located in the containing space, so that when the electric core is subjected to impact or falling and the like, the elastic bending part can elongate when being stretched and / or shorten when being compressed, thereby providing displacement for the movement of the electric core in the containing space of the packaging shell, helping to reduce the stress of the connecting position of the tab and the electric core, and improving the separation or tearing of the tab and the electric core at the connecting position.

[0007] According to some embodiments of the utility model, 0.5≤resistance value of the positive tab / resistance value of the negative tab≤1.5.

[0008] According to some embodiments of the utility model, the tab comprising the elastic bending part comprises a first segment, a second segment and a third segment connected in sequence, the first segment and the second segment are located in the containing space, and the third segment is sealingly connected to the packaging shell and extends outward from the packaging shell; the first segment is electrically connected to the electric core, and the second segment comprises at least one elastic bending part.

[0009] According to some embodiments of the present application, the elastic bending part comprises a first bending section, a second bending section and a third bending section connected in sequence; the first section and the first bending section are arranged at an angle, the second bending section and the first bending section are arranged at an angle, the third bending section and the second bending section are arranged at an angle, and the third section and the third bending section are arranged at an angle.

[0010] According to some embodiments of the present application, the angle between the first section and the first bending section is defined as a, and / or the angle between the second bending section and the first bending section is defined as a, and / or the angle between the third bending section and the second bending section is defined as a, and / or the angle between the third section and the third bending section is defined as a; wherein 90° < a < 135°.

[0011] According to some embodiments of the present application, the second section further comprises a connecting part, and one connecting part is connected between every two adjacent elastic bending parts.

[0012] According to some embodiments of the present application, at least one elastic bending part is convex to the same side of the corresponding tab; and / or, the positive tab and the negative tab are electrically connected to the same side of the battery cell.

[0013] According to some embodiments of the present application, the battery cell is formed by stacking or winding the positive sheet, the diaphragm and the negative sheet in sequence, the positive tab is electrically connected to the positive sheet, and the negative tab is electrically connected to the negative sheet.

[0014] According to some embodiments of the present application, the size of the negative sheet is greater than that of the positive sheet, and the positive tab and the negative tab each comprise at least one elastic bending part; the length of the negative tab is defined as L1, the cross-sectional area of the negative tab is defined as S1, the resistivity of the negative tab is defined as P1, the length of the positive tab is defined as L2, the cross-sectional area of the positive tab is defined as S2, the resistivity of the positive tab is defined as P2, the length of the elastic bending part is defined as W, the maximum length of the elastic bending part after stretching is defined as L, the negative tab comprises N1 elastic bending parts, the positive tab comprises N2 elastic bending parts, on the same side of the battery cell, the distance between the side edge of the positive sheet and the side edge of the negative sheet is defined as OH; wherein P1*L1 / S1 = P2*L2 / S2, and / or L1-N1*(L-W) = L2-N2*(L-W)-OH, and L1 < L2.

[0015] According to some embodiments of the present application, the number of elastic bending parts is defined as N, the stretching amount of the elastic bending part is defined as W1, the elastic modulus of the elastic bending part is defined as M, in the direction of the tab with the elastic bending part along the battery cell, the distance between the end of the battery cell away from the elastic bending part and the packaging shell is defined as H, and the bonding force of the tab and the battery cell is defined as F; wherein N*W1 > H, and / or W1*M < F.

[0016] The additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter in the description of the application. BRIEF DESCRIPTION OF DRAWINGS

[0017] The present application will be further described below in connection with the drawings and examples, wherein:

[0018] Figure 1 A structure diagram of a battery is shown;

[0019] Figure 2 A connection structure diagram of a positive electrode sheet and a positive tab is shown;

[0020] Figure 3 A connection structure diagram of a positive electrode sheet and a positive tab is shown;

[0021] Figure 4 A connection structure diagram of a negative electrode sheet and a negative tab is shown.

[0022] Reference signs:

[0023] Battery 100;

[0024] Encapsulation shell 110; accommodating space 111;

[0025] Battery core 130; positive electrode sheet 131; negative electrode sheet 133;

[0026] Tab 150; first section 151; second section 153; elastic bending part 1531; first bending section 1533; second bending section 1535; third bending section 1537; connecting part 1539; third section 155; positive tab 157; negative tab 159;

[0027] Length direction Y; thickness direction X. DETAILED DESCRIPTION

[0028] The embodiments of the present application will be described in detail below, examples of which are shown in the drawings, wherein the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application.

[0029] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0030] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0031] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0032] In the description of this utility model, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0033] Please see Figures 1 to 2 This application provides a battery 100, which can be used to provide power to electronic devices such as mobile phones, computers, and new energy vehicles.

[0034] The battery 100 includes a casing 110, a cell 130, and two tabs 150.

[0035] The encapsulation shell 110 has a receiving space 111 inside, and the battery cell 130 is disposed in the receiving space 111.

[0036] As an example, the encapsulation shell 110 can be a flexible shell, such as an aluminum-plastic film. The aluminum-plastic film can cover the outside of the battery cell 130, thereby encapsulating the battery cell 130 within the receiving space 111 of the encapsulation shell 110.

[0037] Understandably, the accommodating space 111 is also filled with electrolyte.

[0038] The two tabs 150 are electrically connected to the battery cell 130 and each extends out of the packaging shell 110 after being sealingly connected to the packaging shell 110. One of the two tabs 150 is a positive tab 157 and the other is a negative tab 159, so as to facilitate connection of the tabs 150 to other electrical devices for charging and discharging.

[0039] At least one of the two tabs 150 includes at least one elastic bending portion 1531, which is located in the accommodation space 111 and is configured to elongate when stretched and / or shorten when compressed. In this way, the elastic bending portion 1531 can provide a displacement amount for movement of the battery cell 130 when the battery cell 130 is subjected to impact or drop, which helps to reduce the stress at the connection position of the tab 150 and the battery cell 130, thereby improving the disconnection or tearing of the tab 150 and the battery cell 130 at the connection position.

[0040] The at least one elastic bending portion 1531 can refer to one elastic bending portion 1531, two elastic bending portions 1531, three elastic bending portions 1531, or other numbers of elastic bending portions 1531.

[0041] As an example, the positive tab 157 can be provided with at least one elastic bending portion 1531, or the negative tab 159 can be provided with at least one elastic bending portion 1531, or both the positive tab 157 and the negative tab 159 are provided with at least one elastic bending portion 1531.

[0042] In some embodiments, 0.5≤resistance value of the positive tab 157 / resistance value of the negative tab 159≤1.5, so as to control the heat generation of the positive tab 157 and the negative tab 159 within a suitable range, which helps to improve the overheat failure of the single tab 150.

[0043] As an example, the ratio of the resistance value of the positive tab 157 to the resistance value of the negative tab 159 can be 0.5, 0.8, 1, 1.5, or other values in the interval [0.5, 1.5].

[0044] Preferably, the resistance values of the positive tab 157 and the negative tab 159 are equal, so as to ensure that the heat generation of the positive tab 157 and the negative tab 159 is substantially the same, which helps to further improve the overheat failure of the single tab 150.

[0045] As an example, taking the positive tab 157 as an example, when the elastic bending part 1531 is arranged on the positive tab 157, the length of the positive tab 157 is increased, so that the resistance value of the positive tab 157 is increased, and at this time, the resistance value of the positive tab 157 is greater than the resistance value of the negative tab 159, so that the heat generation of the positive tab 157 is greater than the heat generation of the negative tab 159, and at this time, the problem of overheating failure of the positive tab 157 is prone to occur. When the resistance values of the positive tab 157 and the negative tab 159 are equal, the overheating failure of the positive tab 157 can be improved.

[0046] In some embodiments, the tab 150 including the elastic bending part 1531 can include a first segment 151, a second segment 153 and a third segment 155 connected in sequence.

[0047] The first segment 151 and the second segment 153 can be located in the accommodation space 111, and the third segment 155 can be sealingly connected to the packaging shell 110 and extend outwardly from the packaging shell 110.

[0048] The distribution directions of the first segment 151, the second segment 153 and the third segment 155 are substantially the length direction Y of the tab 150.

[0049] It can be understood that when only one of the two tabs 150 is provided with the elastic bending part 1531, the arrangement modes of the two tabs 150 between the battery cell 130 and the packaging shell 110 are also substantially the same, and both extend outwardly from the packaging shell 110 after being electrically connected to the battery cell 130.

[0050] The first segment 151 can be electrically connected to the battery cell 130, and the second segment 153 includes at least one elastic bending part 1531, so that the elastic bending part 1531 can be arranged substantially at the middle position of the two tabs 150 and located in the accommodation space 111, so as to provide a displacement amount when the tab 150 moves.

[0051] In some embodiments, the third segment 155 can include a sealing part, which can be arranged in a spaced manner with the elastic bending part 1531 and sealingly connected to the packaging shell 110.

[0052] As an example, the battery 100 can further include a tab adhesive, which can be bonded between the sealing part and the packaging shell 110 to insulate and seal the sealing part and the packaging shell 110.

[0053] In some embodiments, the first segment 151, the second segment 153 and the third segment 155 can be integrally formed, which helps to improve the structural strength of the tab 150.

[0054] As an example, the tab 150 can adopt an aluminum, nickel or other metal sheet material, the metal sheet material can be first cut to form a sheet-shaped tab 150 of a required size, and the sheet-shaped tab 150 can be further subjected to stamping, rolling, manual bending or other processing to bend the elastic bending portion 1531 on the tab 150, so that the first section 151, the second section 153 and the third section 155 are integrally formed.

[0055] In some embodiments, the elastic bending portion 1531 can include a first bending section 1533, a second bending section 1535 and a third bending section 1537 connected in sequence.

[0056] The first section 151 and the first bending section 1533 are arranged at an angle, the second bending section 1535 and the first bending section 1533 are arranged at an angle, the third bending section 1537 and the second bending section 1535 are arranged at an angle, and the third section 155 and the third bending section 1537 are arranged at an angle. In this way, when the tab 150 is subjected to force, the angles between the first section 151 and the first bending section 1533, the second bending section 1535 and the first bending section 1533, the second bending section 1535 and the third bending section 1537, and the third section 155 and the third bending section 1537 can all change when the tab 150 is subjected to force, so as to provide a displacement amount for the movement of the battery cell 130, thereby reducing the stress at the connection position of the tab 150 and the battery cell 130, and improving the disconnection or tearing of the tab 150 and the battery cell 130 at the connection position.

[0057] As an example, when the tab 150 is subjected to tension, the angles increase, and when the tab 150 is subjected to compression, the angles decrease.

[0058] It can be understood that, taking one tab 150 as an example, when the second section 153 of the tab 150 includes only one elastic bending portion 1531, the first section 151, the first bending section 1533, the second bending section 1535, the third bending section 1537 and the third section 155 can be connected in sequence.

[0059] When the second section 153 of the tab 150 includes two or more elastic bending portions 1531, the two or more elastic bending portions 1531 can be connected in sequence, i.e., the third bending section 1537 of a previous elastic bending portion 1531 can be connected to the first bending section 1533 of an adjacent another elastic bending portion 1531. In the two elastic bending portions 1531 connected in sequence, the first bending section 1533 of the elastic bending portion 1531 at the head end can be connected to the first section 151, and the third bending section 1537 of the elastic bending portion 1531 at the tail end can be connected to the third section 155.

[0060] In some embodiments, an included angle between the first segment 151 and the first bending segment 1533 is a, and / or an included angle between the second bending segment 1535 and the first bending segment 1533 is a, and / or an included angle between the third bending segment 1537 and the second bending segment 1535 is a, and / or an included angle between the third segment 155 and the third bending segment 1537 is a.

[0061] wherein 90° < a < 135°, so that at least one of the included angles a between the segments can be set as an obtuse angle, and controlled within a suitable range, which helps to avoid the connection between the segments from being broken due to acute or right angle connection, and also ensures that the elastic bending part 1531 has a large enough stretching amount to provide sufficient displacement amount for the movement of the battery cell 130.

[0062] As an example, a can be 91°, 100°, 112°, 134°, or other values in the interval (90°, 135°).

[0063] It should be noted that the included angle between the first segment 151 and the first bending segment 1533, the included angle between the second bending segment 1535 and the first bending segment 1533, the included angle between the third bending segment 1537 and the second bending segment 1535, and the included angle between the third segment 155 and the third bending segment 1537, can be equal or not equal, and can be set according to requirements.

[0064] In some embodiments, the first bending segment 1533, the second bending segment 1535, and the third bending segment 1537 can all be located on the same side of the corresponding tab 150, so that the first bending segment 1533, the second bending segment 1535, and the third bending segment 1537 can be conveniently bent on the tab 150, reducing the manufacturing difficulty.

[0065] As an example, when the positive tab 157 is provided with the elastic bending part 1531, the first bending segment 1533, the second bending segment 1535, and the third bending segment 1537 of each elastic bending part 1531 can all be located on the same side of the positive tab 157.

[0066] As another example, when the negative tab 159 is provided with the elastic bending part 1531, the first bending segment 1533, the second bending segment 1535, and the third bending segment 1537 of each elastic bending part 1531 can all be located on the same side of the negative tab 159.

[0067] It should be noted that, taking the positive tab 157 as an example, when the positive tab 157 is provided with two elastic bending portions 1531, the first bending segment 1533, the second bending segment 1535 and the third bending segment 1537 of the two elastic bending portions 1531 can all be located on the same side of the positive tab 157; or the first bending segment 1533, the second bending segment 1535 and the third bending segment 1537 of one of the elastic bending portions 1531 can all be located on the same side of the positive tab 157, and the first bending segment 1533, the second bending segment 1535 and the third bending segment 1537 of the other elastic bending portion 1531 can all be located on the other side of the positive tab 157.

[0068] In some embodiments, the elastic bending portion 1531 is substantially trapezoidal and protrudes to one side of the tab 150 in the thickness direction X, and the distance between the first bending segment 1533 and the second bending segment 1535 gradually approaches from the tab 150 to the direction away from the tab 150, so as to ensure that the elastic bending portion 1531 can provide sufficient displacement amount when bearing tensile force and compressive force.

[0069] In some embodiments, the second segment 153 can further include a connecting portion 1539, and one connecting portion 1539 is connected between adjacent two elastic bending portions 1531, which helps to improve the situation that the adjacent two elastic bending portions 1531 are directly connected at an acute angle, resulting in the fracture of the connection.

[0070] Specifically, taking the second segment 153 provided with two elastic bending portions 1531 as an example, the two elastic bending portions 1531 are respectively named as a first elastic bending portion and a second elastic bending portion, the first bending segment 1533 of the first elastic bending portion can be connected to the first segment 151, and the third bending segment 1537 of the second elastic bending portion can be connected to the third segment 155. The connecting portion 1539 can be connected between the third bending segment 1537 of the first elastic bending portion and the first bending segment 1533 of the second elastic bending portion, so as to avoid the situation that the third bending segment 1537 of the first elastic bending portion and the first bending segment 1533 of the second elastic bending portion are directly connected at an acute angle, resulting in the fracture of the connection.

[0071] The first segment 151, the connecting portion 1539 and the third segment 155 can be substantially located on the same straight line, and the included angle between the connecting portion 1539 and the third bending segment 1537 of the first elastic bending portion can also be a; the included angle between the connecting portion 1539 and the first bending segment 1533 of the second elastic bending portion can also be a.

[0072] It can be understood that in the present embodiment, the number of elastic bending portions 1531 is greater than or equal to two, and the number of connecting portions 1539 can be one less than the number of elastic bending portions 1531.

[0073] In some embodiments, the first segment 151 and the first bending segment 1533 can be connected by a circular arc at the connection position, so as to reduce stress and reduce the possibility of breakage at the connection position.

[0074] In some embodiments, the first bending segment 1533 and the second bending segment 1535 can be connected by a circular arc at the connection position, so as to reduce stress and reduce the possibility of breakage at the connection position.

[0075] In some embodiments, the second bending segment 1535 and the third bending segment 1537 can be connected by a circular arc at the connection position, so as to reduce stress and reduce the possibility of breakage at the connection position.

[0076] In some embodiments, the third bending segment 1537 and the third segment 155 can be connected by a circular arc at the connection position, so as to reduce stress and reduce the possibility of breakage at the connection position.

[0077] In some embodiments, the at least one elastic bending part 1531 can be convex to the same side of the corresponding tab 150, so that the plurality of elastic bending parts 1531 can be conveniently bent on the tab 150, and the manufacturing difficulty is reduced. In addition, the elastic bending part 1531 only occupies the accommodation space 111 on one side of the tab 150 in the thickness direction X, thereby saving the space in the packaging shell 110.

[0078] In some embodiments, the positive tab 157 and the negative tab 159 can be electrically connected to the same side of the battery cell 130, so that the positive tab 157 and the negative tab 159 can be more conveniently led out from the same side of the packaging shell 110, so as to be electrically connected to other electrical structures.

[0079] The electrical structure can refer to a busbar or other electrical structure.

[0080] Please refer to Figures 2 to 4 In some embodiments, the battery cell 130 can be formed by stacking or winding the positive electrode sheet 131, the separator and the negative electrode sheet 133 in sequence.

[0081] It should be noted that when the battery cell 130 is a stacked battery cell, the positive electrode sheet 131, the separator and the negative electrode sheet 133 can be stacked in sequence to form the stacked battery cell. The number of positive electrode sheets 131 can be one or more, the number of separators can also be one or more, and the number of negative electrode sheets 133 can also be one or more. When the number of positive electrode sheets 131, the number of separators and the number of negative electrode sheets 133 are all multiple, the positive electrode sheets 131 and the negative electrode sheets 133 can be alternately stacked, and the separators are arranged between the positive electrode sheets 131 and the negative electrode sheets 133 to form the stacked battery cell.

[0082] When the battery cell 130 is a jelly-roll battery cell, and the number of the positive electrode sheet 131, the separator, and the negative electrode sheet 133 is multiple, the positive electrode sheet 131 can include a first current collector and a first empty foil area, and the negative electrode sheet 133 can include a second current collector and a second empty foil area, the first current collector and the second current collector are alternately stacked, and the separator is arranged between any adjacent first current collector and second current collector to form the jelly-roll battery cell.

[0083] The first empty foil area and the second empty foil area are located on the same side of the jelly-roll battery cell along the length direction Y and are arranged at intervals. The multiple first empty foil areas are sequentially stacked and connected to form a positive electrode conductive structure, and the multiple second empty foil areas are sequentially stacked and connected to form a negative electrode conductive structure. The first section 151 of the positive electrode tab 157 with the elastic bending part 1531 can be electrically connected (such as welding) to the positive electrode conductive structure, and the first section 151 of the negative electrode tab 159 with the elastic bending part 1531 can be electrically connected (such as welding) to the negative electrode conductive structure.

[0084] When the battery cell 130 is a jelly-roll battery cell, the positive electrode sheet 131 can only be provided with a first current collector, or can be provided with a first current collector and multiple first empty foil areas arranged at intervals. The multiple first empty foil areas can be stacked to form a positive electrode conductive structure. The negative electrode sheet 133 can only be provided with a second current collector, or can be provided with a second current collector and multiple second empty foil areas arranged at intervals. The multiple second empty foil areas can be stacked to form a negative electrode conductive structure. For details, refer to the above jelly-roll battery cell, which will not be described again.

[0085] Among them, for the jelly-roll battery cell, the separator can be a sheet-shaped separator or a bag-shaped separator. When the separator is a bag-shaped separator, the positive electrode sheet 131 or the negative electrode sheet 133 can be arranged in the bag of the bag-shaped separator, and the separator can also separate the positive electrode sheet 131 and the negative electrode sheet 133.

[0086] It can be understood that when the battery cell 130 is arranged in the accommodating space 111, the battery cell 130 and the packaging shell 110 can be insulated, and the insulation mode can be selected according to the needs.

[0087] As an example, a separator can be arranged between the positive electrode sheet 131 and the packaging shell 110 to separate the positive electrode sheet 131 and the packaging shell 110, and a separator can be arranged between the negative electrode sheet 133 and the packaging shell 110 to separate the negative electrode sheet 133 and the packaging shell 110. When the battery cell 130 is a jelly-roll battery cell, the jelly-roll arrangement is generally separator-positive electrode sheet 131-separator-negative electrode sheet 133-separator; when the battery cell 130 is a jelly-roll battery cell, the jelly-roll arrangement is generally separator-positive electrode sheet 131-separator-negative electrode sheet 133-separator, which are sequentially stacked and then wound.

[0088] As another example, an insulating layer can be arranged between the positive tab 131 and the packaging shell 110, and an insulating layer can also be arranged between the negative tab 133 and the packaging shell 110. The insulating layer can be an insulating adhesive paper or an insulating coating or other insulating layer.

[0089] The positive tab 157 can be electrically connected to the positive tab 131, and the negative tab 159 can be electrically connected to the negative tab 133.

[0090] As an example, the positive tab 157 can be welded to the positive tab 131, and the negative tab 159 can be welded to the negative tab 159. Specifically, the positive tab 157 can be partially overlapped with the positive tab 131 and then welded to the positive tab 131, and the negative tab 133 can be partially overlapped with the negative tab 133 and then welded to the negative tab 133.

[0091] Please refer to Figures 2 to 4 In some embodiments, the first section 151 can include a first sub-section and a second sub-section connected to each other, the first sub-section can be electrically connected to the battery cell 130, and the second sub-section can be located outside the battery cell 130 and connected to the second section 153. The length of the first sub-section can be greater than the length of the second sub-section.

[0092] As an example, taking the positive tab 157 provided with the elastic bending portion 1531 as an example, the first sub-section can be overlapped with the positive tab 131 and then welded, and the second sub-section can be located outside the battery cell 130.

[0093] Please refer to Figures 1 to 2 In some embodiments, the positive tab 157 and the negative tab 159 each include at least one elastic bending portion 1531, so that the positive tab 157 and the negative tab 159 each can provide a displacement amount for the movement of the battery cell 130, which helps to further improve the disengagement or tearing of the tab 150 and the battery cell 130 at the connection position.

[0094] The length of the negative tab 159 is defined as L1, the cross-sectional area of the negative tab 159 is S1, the resistivity of the negative tab 159 is P1, the length of the positive tab 157 is L2, the cross-sectional area of the positive tab 157 is S2, and the resistivity of the positive tab 157 is P2.

[0095] Wherein, P1*L1 / S1 = P2*L2 / S2, L1 < L2, so that the resistance values of the positive tab 157 and the negative tab 159 can be controlled to be approximately equal, to improve the phenomenon of overheating of a single tab 150 due to the arrangement of the elastic bending portion 1531. In addition, the battery 100 of the present embodiment can also freely select the values of P1, L1, S1, P2, L2 and S2 according to the above formula to meet different needs.

[0096] It should be noted that the size of the negative plate 133 can be greater than the size of the positive plate 131, which helps the negative plate 133 to provide a larger embedding space for lithium ions, and setting L1 to be less than L2 helps to better adapt to the negative plate 133 and the positive plate 131 with size difference, so as to control the negative tab 159 and the positive tab 157 to be approximately flush at one end of the battery cell 130.

[0097] Please refer to Figures 1 to 4 In some embodiments, the length of the elastic bending part 1531 is defined as W, the maximum length of the elastic bending part 1531 after stretching is L, the negative tab 159 includes N1 elastic bending parts 1531, the positive tab 157 includes N2 elastic bending parts 1531, on the same side of the battery cell 130, the distance between the side edge of the positive plate 131 and the side edge of the negative plate 133 is OH.

[0098] The length W of the elastic bending part 1531 can specifically refer to the length of the elastic bending part 1531 along the length direction Y of the tab 150, and is approximately the maximum distance between the first bending segment 1533 and the third bending segment 1537.

[0099] The maximum length L of the elastic bending part 1531 after stretching can be the extension length of the elastic bending part 1531, and is approximately the sum of the extension length of the first bending segment 1533, the extension length of the second bending segment 1535, and the extension length of the third bending segment 1537.

[0100] When the positive plate 131 and the negative plate 133 are stacked, the positive plate 131 can be located within the area range of the positive plate 131, and there is a distance difference between the four side edges of the positive plate 131 and the corresponding four side edges of the negative plate 133, which can be OH.

[0101] Wherein, L1-N1*(L-W)=L2-N2*(L-W)-OH, L1<L2, so that the size of the positive tab 157 and the negative tab 159 can be better controlled through the formula.

[0102] In addition, the battery 100 of the embodiments of the present application can also flexibly adjust the length of the positive tab 157, the length of the negative tab 159, the cross-sectional area of the positive tab 157, the cross-sectional area of the negative tab 159, the number of elastic bending parts 1531, the size of the positive plate 131 and the size of the negative plate 133 to meet different needs, while ensuring that the resistance values of the two tabs 150 are equal, through the formula P1*L1 / S1=P2*L2 / S2 and the formula L2-N2*(L-W)-OH=L1-N1*(L-W).

[0103] As an example, in selecting the value of L2, the formula P1*L1 / S1=P2*L2 / S2 can be substituted into the formula L2-N2*(L-W)-OH=L1-N1*(L-W) to obtain L2=((N1-N2)*(L-W)+OH) / ((P2*S1 / P1*S2)-1).

[0104] In some embodiments, the number of the elastic bending portion 1531 is defined as N, the stretching amount of the elastic bending portion 1531 is defined as W1, and the distance between the end of the battery cell 130 away from the elastic bending portion 1531 and the bottom of the packaging shell 110 along the length direction Y of the battery cell 130, i.e., the direction of the battery cell 130 to the tab 150 including the elastic bending portion 1531, is defined as H, wherein N*W1>H, so that the elastic bending portion 1531 can provide a large enough displacement amount for the movement of the battery cell 130 to meet the movement amount of the battery cell 130 in the gap between the battery cell 130 and the bottom of the packaging shell 110, further reducing the pulling of the tab 150 when the battery cell 130 moves, and further improving the disconnection or tearing of the tab 150 and the battery cell 130 at the connection position.

[0105] In some embodiments, the packaging shell 110 has opposite top and bottom along the length direction Y of the battery cell 130, i.e., the direction of the battery cell 130 to the tab 150, the top is used for sealing connection with the tab 150, and the two ends of the battery cell 130 are spaced apart from the top and the bottom, respectively, and the distance between the end of the battery cell 130 away from the tab 150 and the bottom of the packaging shell 110 can be H.

[0106] In some embodiments, the elastic modulus of the elastic bending portion 1531 is defined as M, and the bonding force of the connection between the tab 150 and the battery cell 130 is defined as F, wherein M and F can be obtained by pre-testing.

[0107] As an example, taking the positive tab 157 provided with the elastic bending portion 1531 as an example, the bonding force after welding between the positive tab 157 and the positive plate 131 is F.

[0108] As another example, taking the negative tab 159 provided with the elastic bending portion 1531 as an example, the bonding force after welding between the negative tab 159 and the negative plate 133 is F.

[0109] In some embodiments, W1*M<F, W1*M is approximately the maximum tensile force that the tab 150 can withstand, and the maximum tensile force that the tab 150 can withstand is less than the bonding force at the connection position of the tab 150 and the battery cell 130, so as to improve the disconnection or tearing of the tab 150 and the battery cell 130 at the connection position.

[0110] In the battery 100 provided by the embodiment of the application, at least one of the two tabs 150 is arranged to include at least one elastic bending part 1531, the elastic bending part 1531 is located in the accommodating space 111, and when the battery cell 130 is subjected to impact or drop, the elastic bending part 1531 can be elongated when stretched and / or shortened when compressed, so as to provide a displacement amount for the movement of the battery cell 130 in the accommodating space 111 of the packaging shell 110, and help to reduce the stress at the connection position of the tab 150 and the battery cell 130, so as to improve the disconnection or tearing of the tab 150 and the battery cell 130 at the connection position.

[0111] The embodiment of the utility model has been described in detail in combination with the drawings above, but the utility model is not limited to the above-mentioned embodiment, and various changes can be made within the knowledge range possessed by the ordinary skilled in the art without departing from the purpose of the utility model. In addition, the embodiments of the utility model and the features in the embodiments can be combined with each other without conflict.

Claims

1. A battery, characterized by, The application relates to a battery cell, which comprises: a packaging shell, which is internally provided with a containing space; an electric core, which is arranged in the containing space; and two tab terminals, which are both electrically connected to the electric core and both extend out of the packaging shell after being sealingly connected to the packaging shell. At least one of the two tab terminals comprises at least one elastic bending part, which is arranged in the containing space and is configured to be elongated when being stretched and / or shortened when being compressed. 0.5<=the resistance value of the positive tab terminal / the resistance value of the negative tab terminal<=1.

5.

2. The battery of claim 1, wherein, The tab terminal comprising the elastic bending part comprises a first section, a second section and a third section which are sequentially connected, the first section and the second section are both arranged in the containing space, and the third section is sealingly connected to the packaging shell and extends out of the packaging shell.

3. The battery of claim 1, wherein, The first section is electrically connected to the electric core, and the second section comprises at least one elastic bending part. The elastic bending part comprises a first bending section, a second bending section and a third bending section which are sequentially connected.

4. The battery of claim 3, wherein, The first section and the first bending section are arranged at an angle, the second bending section and the first bending section are arranged at an angle, the third bending section and the second bending section are arranged at an angle, and the third section and the third bending section are arranged at an angle. The angle between the first section and the first bending section is defined as a, the angle between the second bending section and the first bending section is defined as a, the angle between the third bending section and the second bending section is defined as a, and the angle between the third section and the third bending section is defined as a.

5. The battery of claim 4, wherein, 90<=a<=135. The second section further comprises a connecting part, and one connecting part is arranged between two adjacent elastic bending parts.

6. The battery of claim 3, wherein, At least one elastic bending part is convex to the same side of the corresponding tab terminal.

7. The battery according to any one of claims 1 to 6, characterized in that, The positive tab terminal and the negative tab terminal are electrically connected to the same side of the electric core. The electric core is formed by sequentially stacking or winding a positive electrode sheet, a diaphragm and a negative electrode sheet, the positive tab terminal is electrically connected to the positive electrode sheet, and the negative tab terminal is electrically connected to the negative electrode sheet.

8. The battery according to any one of claims 1 to 6, characterized in that The size of the negative electrode sheet is greater than that of the positive electrode sheet, and the positive tab terminal and the negative tab terminal both comprise at least one elastic bending part.

9. The battery of claim 8, wherein, The length of the negative tab terminal is defined as L1, the cross-sectional area of the negative tab terminal is defined as S1, the resistivity of the negative tab terminal is defined as P1, the length of the positive tab terminal is defined as L2, the cross-sectional area of the positive tab terminal is defined as S2, the resistivity of the positive tab terminal is defined as P2, the length of the elastic bending part is defined as W, the maximum length of the elastic bending part after being stretched is defined as L, the negative tab terminal comprises N1 elastic bending parts, the positive tab terminal comprises N2 elastic bending parts, and the distance between the side edge of the positive electrode sheet and the side edge of the negative electrode sheet on the same side of the electric core is defined as OH. P1*L1 / S1=P2*L2 / S2, and / or L1-N1*(L-W)=L2-N2*(L-W)-OH, and L1L2. ​ 10. The battery according to any one of claims 1 to 6, characterized in that, The number of the elastic bending parts is defined as N, the stretching amount of the elastic bending part is defined as W1, the elastic modulus of the elastic bending part is defined as M, the distance between the end of the battery cell away from the elastic bending part and the packaging shell in the direction of the battery cell to the tab including the elastic bending part is defined as H, and the bonding force of the tab and the battery cell is defined as F; wherein N*W1>H and / or W1*M<F.

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