Batteries and battery devices

Abstract

This disclosure relates to the field of battery technology, and discloses a battery and a battery device; the battery includes a terminal assembly, a cell, and at least two welded connections; the cell includes a main body and a tab portion; at least two welded connections are connected to the tab portion and the terminal assembly, the solder area connecting the welded connection portion and the tab portion is s, the number of welded connections is n, and the ratio of the number of welded connections n to the solder area s is greater than or equal to 0.15 mm. ‑2 Less than or equal to 10.5mm ‑2 This battery ensures an appropriate overcurrent area between the terminal assembly and the tabs, preventing excessive heat generation during charging and discharging and avoiding the safety risk of thermal runaway.

Description

Technical Field

[0001] This disclosure relates to the field of battery technology, and more specifically, to a battery and a battery device including the battery. Background Technology

[0002] Welding is a common process in battery manufacturing; the battery terminal assembly is connected to the tabs through welding. However, there are currently no restrictions on the welding between the terminal assembly and the tabs, resulting in poor current carrying capacity after welding, and easy overheating, especially during charging and discharging, where severe overheating can easily lead to thermal runaway.

[0003] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Utility Model Content

[0004] The purpose of this disclosure is to overcome the shortcomings of the aforementioned related technologies and to provide a battery and a battery device including the battery.

[0005] According to one aspect of this disclosure, a battery is provided, comprising:

[0006] pole assembly;

[0007] The battery cell includes the main body and the electrode tabs;

[0008] At least two welded connections are provided, connecting the tab and the pole assembly. The weld area connecting the welded connection to the tab is s, the number of welded connections is n, and the ratio of the number of welded connections n to the weld area s, n / s, is greater than or equal to 0.15 mm. -2 Less than or equal to 10.5mm -2 .

[0009] In the battery disclosed herein, the ratio of the number of connecting parts n to the solder area s, n / s, is greater than or equal to 0.15 mm. -2 Less than or equal to 10.5mm -2 On the one hand, it ensures that the welding heat required during welding is moderate, the melting area of ​​the tab is moderate, and the tab and welding head are not easily stuck together, so as to ensure welding quality, avoid high resistance after welding which affects the current carrying capacity, and avoid affecting the service life of the welding head; on the other hand, it ensures that the current carrying area between the terminal assembly and the tab is appropriate, avoids excessive heat generation during battery charging and discharging, and avoids the safety risk of thermal runaway.

[0010] According to another aspect of this disclosure, a battery device is provided, comprising:

[0011] Battery box;

[0012] The battery is the battery described above, and the battery is located inside the battery box.

[0013] The battery device disclosed herein, on the one hand, ensures that the welding heat required during welding is moderate, the melting area of ​​the tab is moderate, and the tab and welding head are not prone to sticking, so as to ensure welding quality, avoid high resistance after welding that affects the current carrying capacity, and thus ensure the electrical performance of the battery; and also avoids affecting the service life of the welding head; on the other hand, it ensures that the current carrying area between the terminal assembly and the tab is appropriate, avoids excessive heat generation during battery charging and discharging, avoids the safety risk of thermal runaway, and thus ensures the safety performance of the battery device.

[0014] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0015] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0016] Figure 1 This is a three-dimensional structural diagram of an example embodiment of the battery disclosed herein.

[0017] Figure 2 for Figure 1 A partial cross-sectional view of the battery.

[0018] Figure 3 for Figure 2 A three-dimensional structural diagram of the intermediate connection section.

[0019] Figure 4 for Figure 2 A top view of the connection between the intermediate connector and the electrode ear.

[0020] Figure 5 This is a schematic diagram of another example embodiment of the terminal assembly in the battery disclosed herein.

[0021] Explanation of reference numerals in the attached figures:

[0022] 1. Battery casing; 11. First casing; 12. Second casing;

[0023] 2. Terminal assembly; 21. Adapter section; 211. Adapter plate; 212. Adapter post; 22. Battery terminal post;

[0024] 3. Battery cell; 31. Main body; 32. Electrode section; 32a. First electrode; 32b. Second electrode;

[0025] 4. Welded joints. Detailed Implementation

[0026] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore detailed descriptions of them will be omitted. Furthermore, the drawings are merely illustrative of this disclosure and are not necessarily drawn to scale.

[0027] Although relative terms such as "up" and "down" are used in this specification to describe the relative relationship of one component of an icon to another, these terms are used only for convenience, such as according to the orientation of the examples shown in the accompanying drawings. It is understood that if the device of the icon is flipped upside down, the component described as "up" will become the component described as "down." When a structure is "up" of another structure, it may mean that the structure is integrally formed on the other structure, or that the structure is "directly" mounted on the other structure, or that the structure is "indirectly" mounted on the other structure through another structure.

[0028] The terms “a,” “one,” “the,” “the,” and “at least one” are used to indicate the presence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first,” “second,” and “third,” etc., are used only as markers and are not a limitation on the number of objects.

[0029] In this application, unless otherwise expressly specified and limited, the term "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection through an intermediate medium. "And / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Furthermore, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0030] This disclosure provides an exemplary embodiment of a battery, with reference to... Figures 1-5As shown, the battery may include a terminal assembly 2, a cell 3, and at least two welded connection portions 4; the cell 3 may include a main body portion 31 and a tab portion 32; at least two welded connection portions 4 are connected to the tab portion 32 and the terminal assembly 2, the solder area of ​​the welded connection portion 4 connecting to the tab portion 32 is s, the number of welded connection portions 4 is n, and the ratio of the number of welded connection portions 4 n to the solder area s is greater than or equal to 0.15mm. -2 Less than or equal to 10.5mm -2 .

[0031] The battery disclosed herein ensures, on the one hand, that the welding heat required during welding is moderate, the melting area of ​​the tab 32 is moderate, and the tab 32 and the welding head are not easily stuck together, so as to ensure welding quality, avoid high resistance after welding that affects the overcurrent, and avoid affecting the service life of the welding head; on the other hand, it ensures that the overcurrent area between the terminal assembly 2 and the tab 32 is appropriate, so as to avoid excessive heat generation during battery charging and discharging and avoid the safety risk of thermal runaway.

[0032] In some exemplary embodiments of this disclosure, reference is made to Figure 1 As shown, the battery can be configured as a generally cuboid structure, therefore, the battery casing 1 can also be configured as a generally cuboid structure. Specifically, the battery casing 1 may include a first casing 11 and a second casing 12. The first casing 11 can be configured as a generally cuboid structure, and the second casing 12 can be configured as a rectangular plate. The first casing 11 has a cavity, and an opening communicating with the cavity is provided on one side of the first casing 11, which can be formed by removing one of the largest faces of the first casing 11. The first casing 11 has a flange around its opening, and the second casing 12 is connected to the flange and closes the opening of the first casing 11. Accordingly, the first casing 11 and the second casing 12 together form a receiving space for accommodating the battery cell 3. The first casing 11 can be a one-piece molded structure.

[0033] Two recessed structures are provided on the side of the first housing 11 away from the second housing 12, and the two recessed structures are located at both ends of the first housing 11 in the length direction.

[0034] Of course, in other exemplary embodiments of this disclosure, the battery casing 1 may include a cover plate, a bottom plate, and four side plates; the four side plates are arranged opposite each other in pairs; the four side plates are connected end to end in sequence to form a rectangular cylindrical shape. A cover plate is connected to one side of each of the four side plates, and a bottom plate is connected to the opposite side of each of the four side plates. The bottom plate and the cover plate may be rectangular, and the cover plate, the bottom plate, and the four side plates surround to form an accommodating space; moreover, the cover plate, the bottom plate, and the four side plates may be an integrally formed structure, which can reduce the welds of the battery casing 1 to improve the sealing performance of the battery casing 1; or they may be separately formed and then connected into one piece by welding or other methods.

[0035] Of course, in other exemplary embodiments of this disclosure, the base plate and cover plate may be configured as circular, elliptical, trapezoidal, etc., and the side plates may be configured as one or more, and formed in a circular, elliptical, trapezoidal, etc., so that the battery casing 1 is formed as cylindrical, elliptical cylindrical, prismatic, etc.

[0036] The battery casing 1 can be made of aluminum, steel or other metals, alloys, etc. Of course, it can also be made of other materials, which will not be listed here.

[0037] Reference Figure 2 As shown, a battery cell 3 is disposed inside the battery casing 1. The battery cell 3 may include a main body 31 and a tab 32.

[0038] In some exemplary embodiments of this disclosure, the main body 31 may be configured as a stacked structure. In order to cooperate with the rectangular battery casing 1, the main body 31 is also configured as a rectangular structure. The main body 31 may include a first electrode, a separator, and a second electrode arranged in sequence, and the first electrode, the separator, and the second electrode are all configured as multiple layers.

[0039] Of course, in some other exemplary embodiments of this disclosure, the main body 31 can be wound, and the layered structure formed by the first electrode, the separator and the second electrode is wound to form the wound main body 31.

[0040] The first electrode is the negative electrode, and the second electrode is the positive electrode. The first electrode is made of copper, for example, copper or a copper alloy. The second electrode is made of aluminum, for example, aluminum or an aluminum alloy. The first and second electrodes are coated with different active materials.

[0041] The main body 31 has a first end face and a second end face disposed opposite to each other along its length direction. A first electrode tab 32a and a second electrode tab 32b may be disposed on opposite end faces along the length direction of the main body 31. For example, the first electrode tab 32a may be disposed on the first end face and the second electrode tab 32b may be disposed on the second end face. Both the first electrode tab 32a and the second electrode tab 32b are electrode tab portions 32.

[0042] Specifically, the first electrode tab 32a is connected to the first electrode plate, making the first electrode tab 32a a negative electrode tab; it can be a part of the first electrode plate extending out of the first end face of the main body 31 and stacked together to form the first electrode tab 32a, and the first electrode tab 32a can extend continuously along the length direction of the main body 31; moreover, the material of the first electrode tab 32a is the same as the material of the first electrode plate, for example, both are copper, copper alloy, etc.

[0043] The second electrode tab 32b is connected to the second electrode plate, making the second electrode tab 32b a positive electrode tab; it can be a part of the second electrode plate extending out of the second end face of the main body 31 and stacked together to form the second electrode tab 32b, and the second electrode tab 32b can extend continuously along the length direction of the main body 31; moreover, the material of the second electrode tab 32b is the same as the material of the second electrode plate, for example, both are aluminum, aluminum alloy, etc.

[0044] Of course, in some other exemplary embodiments of this disclosure, the first electrode tab 32a can be bent to the side of the first end face away from the main body portion 31. In this case, the first electrode tab 32a can cover a portion of the first end face or cover the entire first end face; the second electrode tab 32b can be bent to the side of the second end face away from the main body portion 31. In this case, the second electrode tab 32b can cover a portion of the first end face or cover the entire second end face. The first electrode tab 32a and the second electrode tab 32b can be bent to the same side of the main body portion 31.

[0045] It should be noted that the first tab 32a and the second tab 32b are conductive foil areas without active material coating, that is, no active material coating is applied to the first tab 32a and the second tab 32b. The first tab 32a and the second tab 32b are current collector layers used for transmitting current.

[0046] For the laminated main body 31, the number of layers of the first electrode is generally equal to the number of layers of the first tab 32a, so that all the first electrodes can be electrically connected through the first tab 32a; similarly, the number of layers of the second electrode is generally equal to the number of layers of the second tab 32b, so that all the second electrodes can be electrically connected through the second tab 32b. Therefore, the first tab 32a may include multiple tab layers, and the second tab 32b may include multiple tab layers.

[0047] For the wound main body 31, the number of layers of the first tab 32a can be less than or equal to the number of winding layers of the first electrode, and the number of layers of the second tab 32b can also be less than or equal to the number of winding layers of the second electrode.

[0048] In some exemplary embodiments of this disclosure, reference is made to Figure 2 As shown, a through hole is provided on the second housing 12. The terminal assembly 2 passes through the through hole on the second housing 12, so that one end of the terminal assembly 2 can extend into the battery housing 1, and a welding connection part 4 is provided between the terminal assembly 2 and the tab 32, that is, the fixed connection between the terminal assembly 2 and the tab 32 is achieved by the welding connection part 4.

[0049] In this example implementation, refer to Figure 2 , Figure 3 and Figure 4As shown, the terminal assembly 2 may include an adapter portion 21 and a battery terminal 22. The adapter portion 21 may include an adapter plate 211 and an adapter post 212. The adapter post 212 is connected to the adapter plate 211. The adapter plate 211 may be rectangular, and the adapter post 212 may be cylindrical. The adapter plate 211 is located inside the battery housing 1. The adapter post 212 passes through a through hole in the second housing 12, and one end of the adapter post 212 extends outside the battery housing 1. The battery terminal 22 may be L-shaped. The battery terminal 22 has a through hole, and the adapter post 212 passes through the through hole in the battery terminal 22 and is riveted to the battery terminal 22. The battery terminal 22 is located on the side of the second housing 12 opposite to the first housing 11, so that the battery terminal 22 protrudes from the second housing 12. When multiple batteries are used together, the battery terminal 22 may be accommodated in a recessed structure on the first housing 11 of an adjacent battery.

[0050] The adapter 21 increases the connection area between the pole assembly 2 and the tab 32 to ensure a strong connection between the pole assembly 2 and the tab 32.

[0051] Of course, the structure of the terminal assembly 2 is not limited to the above description. For example, the terminal assembly 2 may only include the battery terminal 22, one end of which extends through the through hole on the second housing 12 into the battery housing 1 and is connected to the tab portion 32 by the welding connection portion 4; the adapter portion 21 may only include the adapter plate 211, one end of which extends through the through hole on the second housing 12 into the battery housing 1 and is fixedly connected to the adapter plate 211.

[0052] The welded connection 4 can be directly connected to the pole assembly 2. Specifically, the welded connection 4 and the pole assembly 2 can be an integrally formed structure. For example, the welded connection 4 can be formed by stamping the adapter 21 of the pole assembly 2. Of course, the welded connection 4 can also be formed on the adapter 21 by machining, making the welded connection 4 a protruding structure provided on the adapter 21. Generally, the precision of the welded connection 4 located in the middle position can be guaranteed, but the precision of the welded connection 4 located at the edge position is poor, especially for the stamping process.

[0053] Of course, the welding connection part 4 and the pole assembly 2 may not be directly connected. For example, the welding connection part 4 and the pole assembly 2 may be connected by welding, screws, riveting, etc. The welding connection part 4 may not be a protruding structure provided on the adapter part 21. For example, the welding connection part 4 may be a weld mark formed between the electrode tab part 32 and the pole assembly 2, that is, the welding connection part 4 is formed entirely by welding.

[0054] The welding connection part 4 and the electrode lug part 32 can be connected by welding. Specifically, the welding connection part 4 and the electrode lug part 32 can be connected as one piece by resistance welding. After resistance welding, the welding connection part 4 and the electrode lug part 32 are connected to form a weld mark.

[0055] Resistance welding is a welding method that uses the resistance heat generated when an electric current passes through the workpieces as a heat source to heat the workpieces, causing them to melt locally and form a weld point or weld seam. When current passes through two contacting workpieces, heat is generated at the contact point due to the resistance of the workpieces. This heat melts the metal at the contact point, forming a weld nugget. Under pressure, the weld nugget gradually increases in size and solidifies, eventually forming a strong weld mark.

[0056] During welding, the adapter 21 of the electrode assembly 2 can be placed on the welding base, the tab 32 can be placed on the adapter 21, and the welding head can be fixed on the tab 32. The number of welding heads is consistent with the number of weld marks to be formed, or the number of welding connection parts 4 can be said to be consistent with the number of welding heads. The position of the welding head is consistent with the position of the weld marks to be formed, or the position of the welding head is consistent with the position of the welding connection part 4. The welding base and the welding head are connected to the welding power source so that the current flows through the welding base, the adapter 21 and the tab 32, at least two welding connection parts 4, and the welding head, thereby realizing the resistance welding of the adapter 21 and the tab 32.

[0057] Of course, in other exemplary embodiments of this disclosure, the welded connection 4 and the electrode lug 32 can also be connected by other welding methods, which will not be described in detail here.

[0058] Reference Figure 4 As shown in the figure, the welded connection 4 and the adapter plate 211 are represented by dashed lines because they are obscured by the tab 32, and different dashed lines represent different positions; the weld area connecting the welded connection 4 and the tab 32 is s, the number of welded connections 4 is n, and the ratio of the number of welded connections 4 n to the weld area s, n / s, is greater than or equal to 0.15mm. -2 Less than or equal to 10.5mm -2 For example, the ratio n / s of the number of welded joints 4 to the weld area s can be 0.5 mm. -2 1mm -2 1.5mm -2 2mm -2 2.5mm -2 3mm -2 3.5mm -2 4mm -2 4.5mm -2 5mm -2 5.5mm -2 6mm -2 6.5mm-2 7mm -2 7.5mm -2 8mm -2 8.5mm -2 9mm -2 9.5mm -2 10mm -2 wait.

[0059] If the ratio of the number n of welded joints 4 to the weld area s, n / s, is too small, the welding heat required during welding will be too large, and too much of the tab 32 will be melted. This will cause the tab 32 to easily stick to the welding head, thus affecting the service life of the welding head. In addition, the welding quality will be poor, resulting in higher resistance and affecting the overcurrent.

[0060] If the ratio n / s of the number n of welded connection parts 4 to the weld area s is too large, the weld area is the overcurrent area between the welded connection part 4 and the tab part 32, which leads to the overcurrent area between the pole assembly 2 and the tab part 32 being too small, resulting in excessive heat generation during battery charging and discharging, which can easily lead to the safety risk of thermal runaway.

[0061] The above-mentioned numerical range not only ensures that the welding heat required during welding is moderate, the melting area of ​​the tab 32 is moderate, and the tab 32 and the welding head are not easily stuck together, so as to ensure welding quality, avoid high resistance after welding that affects the overcurrent, and avoid affecting the service life of the welding head; but also ensures that the overcurrent area between the terminal assembly 2 and the tab 32 is appropriate, so as to avoid excessive heat generation during battery charging and discharging and avoid the safety risk of thermal runaway.

[0062] In some exemplary embodiments of this disclosure, please continue to refer to Figure 4 As shown, the connection area between the welded connection part 4 and the pole assembly 2 is m. The ratio of the weld area s to the connection area m, s / m, is greater than or equal to 0.5 and less than or equal to 0.9. For example, the ratio of the weld area s to the connection area m, s / m, can be 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, etc.

[0063] The connection area m between the welded connection part 4 and the pole post assembly 2 is greater than or equal to the solder area s. However, if the ratio s / m of the solder area s to the connection area m is too small, the connection area m will be too large, resulting in a large area of ​​the welded connection part 4 near the pole tab not being welded to the pole tab. Moreover, when the connection area m between the welded connection part 4 and the pole post assembly 2 is set to be large, it is difficult to set an appropriate number of welded connections 4 on the pole post assembly 2 with a fixed area, making it difficult to meet the above requirements for the number of welded connections 4 n.

[0064] Alternatively, the connection area m between the welded connection part 4 and the pole assembly 2 is greater than or equal to 0.75 mm. 2 Less than or equal to 40mm 2 For example, the connection area m between the welded connection 4 and the pole assembly 2 can be 2 mm. 2 5mm 2 7mm 2 10mm 2 13mm 2 15mm 2 18mm 2 20mm 2 22mm 2 25mm 2 27mm 2 30mm 2 33mm 2 35mm 2 38mm 2 wait.

[0065] If the connection area m between the welded connection part 4 and the pole assembly 2 is too small, it is difficult to set a weld mark of a suitable area on the welded connection part 4 with a fixed area, so that the weld mark area s is difficult to meet the above requirements.

[0066] In some exemplary embodiments of this disclosure, when the material of the tab 32 includes copper, that is, when the tab 32 is the first tab 32a (negative tab); since copper has a better conductivity and the copper surface is not easily oxidized, the tab 32 and each welding connection 4 on the pole assembly 2 can conduct electricity and shunt well during the resistance welding process, so that the tab 32 and each welding connection 4 can be well welded to form a solder mark that meets the above requirements. Therefore, the ratio of the number n of welding connection 4 to the solder mark area s can meet the above requirements.

[0067] In some exemplary embodiments of this disclosure, when the material of the tab 32 includes aluminum, that is, when the tab 32 is the second tab 32b (positive tab); the ratio n / s of the number of welded connection portions 4 to the solder area s is greater than or equal to 0.15 mm. -2 Less than or equal to 9.8mm -2 For example, the ratio n / s of the number of welded joints 4 to the weld area s can be 0.4 mm. -2 0.8mm -2 1.4mm -2 1.9mm -2 2.6mm -2 3.1mm -2 3.4mm -2 3.9mm -24.6mm -2 5.2mm -2 5.4mm -2 6.2mm -2 6.7mm -2 7.2mm -2 7.7mm -2 8.4mm -2 8.7mm -2 9.1mm -2 9.6mm -2 wait.

[0068] Because aluminum has poor electrical conductivity and its surface is prone to oxidation, forming an oxide layer that further reduces conductivity, the resistance of a weld joint 4 decreases significantly after its oxide layer is broken down during resistance welding. Most of the current flows through the broken weld joint 4, with less flowing through the others, resulting in a smaller number of weld joints 4, n. Therefore, it is necessary to appropriately reduce the ratio of the number of weld joints 4, n, to the solder area, s, i.e., appropriately reduce the number of weld joints 4, n, to increase the solder area, thus ensuring the total current-carrying area between the tab 32 and the electrode assembly 2.

[0069] In some exemplary embodiments of this disclosure, reference is made to Figure 2 As shown, the height h of the portion of the welded connection 4 located between the pole post assembly 2 and the electrode lug 32 is greater than or equal to 0.2 mm and less than or equal to 1.5 mm. For example, the height h of the portion of the welded connection 4 located between the pole post assembly 2 and the electrode lug 32 can be 0.3 mm, 0.5 mm, 0.7 mm, 0.9 mm, 1 mm, 1.2 mm, 1.4 mm, etc.

[0070] Since the weld area s and the welded connection part 4 are formed by melting and solidifying the welded connection structure through the welding process, if the height h of the part of the welded connection part 4 located between the pole post assembly 2 and the pole ear part 32 is too large, the weld area s formed by welding may be too small and cannot meet the above requirements.

[0071] If the height h of the welded connection part 4 located between the pole post assembly 2 and the pole lug 32 is too small, it is easy for the pole post assembly 2 and the pole lug 32 to stick together.

[0072] The above numerical range not only ensures that the weld area s formed by welding can meet the above requirements, but also avoids adhesion between the pole post assembly 2 and the pole ear 32.

[0073] In some exemplary embodiments of this disclosure, reference is made to Figure 3 and Figure 4As shown, at least three welded joints 4 are provided, and these three welded joints 4 are arranged in at least one triangle; for example, there can be three, four, five, or more welded joints 4; three welded joints 4 are arranged in one triangle; four welded joints 4 are arranged in two triangles, with the two triangles sharing a side; five welded joints 4 are arranged in three triangles, with adjacent triangles sharing a side. These welded joints 4 are formed through the same resistance welding process. This arrangement makes the at least two welded joints 4 relatively concentrated, and the pressure applied during resistance welding is also relatively concentrated. Pressure differences are less likely to occur between the welded joints 4, resulting in smaller height differences and more uniform weld areas, thus ensuring more uniform current flow capacity for each welded joint 4.

[0074] A triangle can be an isosceles triangle, an equilateral triangle, a right triangle, or any other non-special triangle.

[0075] In some exemplary embodiments of this disclosure, reference is made to Figure 5 As shown, at least four welded joints 4 are provided, and the at least four welded joints 4 are arranged in at least one quadrilateral; for example, there can be four, six, eight or more welded joints 4; four welded joints 4 are arranged in one quadrilateral, for example, the quadrilateral can be a rectangle, parallelogram, rhombus, etc.; six welded joints 4 are arranged in two quadrilaterals, with the two quadrilaterals sharing a side; eight welded joints 4 are arranged in three quadrilaterals, with adjacent quadrilaterals sharing a side. These welded joints 4 are formed by the same resistance welding process. This arrangement makes the at least two welded joints 4 relatively concentrated, and the pressure applied during the resistance welding process is also relatively concentrated. It is not easy for pressure differences to be generated between the welded joints 4, thereby making the height difference between the welded joints 4 smaller and the weld area more uniform, so as to ensure that the current carrying capacity of the welded joints 4 is more uniform.

[0076] In some exemplary embodiments of this disclosure, at least two welded joints 4 may be arranged in a straight line. These welded joints 4 are formed by the same resistance welding process.

[0077] It should be noted that the above arrangement can be a figure formed by connecting the center points of the welded connection structure 41.

[0078] Optionally, the minimum spacing K between two adjacent welded joints 4 is greater than or equal to 1 mm and less than or equal to 5 mm. For example, the minimum spacing K between two adjacent welded joints 4 can be 1.2 mm, 1.5 mm, 1.7 mm, 2 mm, 2.3 mm, 2.5 mm, 2.8 mm, 3 mm, 3.2 mm, 3.5 mm, 3.7 mm, 4 mm, 4.3 mm, 4.5 mm, 4.8 mm, etc.

[0079] If the minimum spacing K between two adjacent welded joints 4 is too large, it is easy to result in not being able to set a sufficient number of welded joints 4, so that the number n of welded joints 4 is difficult to meet the above requirements; moreover, during the preparation of the welded joints 4, due to process errors, the height difference of the welded joints 4 is easy to be too large, which makes it easy to generate a pressure difference between the welded joints 4 during the resistance welding process, resulting in a large difference in the weld area of ​​each weld, making it easy for the position with the smaller weld area to melt and break.

[0080] If the minimum distance K between two adjacent welded joints 4 is too small, heat will easily accumulate between the two adjacent welded joints 4 during welding, which will easily cause the two adjacent welded joints 4 to stick together.

[0081] The above numerical range not only ensures that the number n of welded joints 4 meets the above requirements, making the height difference of each welded joint 4 small, the pressure difference between welded joints 4 small during resistance welding, and the weld area relatively uniform, thus avoiding melting at some welded joints 4; but also prevents adjacent welded joints 4 from easily sticking together.

[0082] Alternatively, the shape of the orthographic projection of the welded connection 4 on the first reference plane is circular, so that the heat is diffused more evenly during the resistance welding process, and the weld mark formed is also basically circular, ensuring that the strength of the welded connection 4 and the electrode tab 32 are uniform and the current carrying capacity is also uniform.

[0083] The first reference surface is parallel to the side of the pole post assembly 2 where the pole lug 32 is connected. Specifically, the first reference surface is parallel to the side of the pole post assembly 2 where the welding connection part 4 is provided.

[0084] It should be noted that a circle can be not only a circle in the strict sense, but also an approximate circle with a certain degree of error. The error range varies depending on the equipment and preparation process. Therefore, within the error range of the equipment and preparation process, they are considered to be the same.

[0085] Of course, in some other exemplary embodiments of this disclosure, the shape of the orthographic projection of the welded connection 4 on the first reference plane can be an ellipse, a rectangle, or other regular or irregular shapes; generally, the shape of the orthographic projection of the welded connection 4 on the first reference plane can be consistent with the shape of the welding head.

[0086] Alternatively, the weld area s connecting the welded joint 4 and the tab 32 is greater than or equal to 0.65 mm. 2 Less than or equal to 20mm 2 For example, the weld area s connecting the welded joint 4 and the tab 32 can be 1 mm. 2 3mm 2 5mm 2 8mm 2 10mm 2 12mm 2 15mm 2 17mm 2 wait.

[0087] If the solder area s connecting the welded connection part 4 and the electrode part 32 is too small, it cannot meet the overcurrent requirements, and the resistance is too large, which can easily cause overheating and other defects.

[0088] If the weld area s connecting the welded joint 4 and the tab 32 is too large, the current required during welding will be large, which will easily cause the tab 32 to be welded through, forming a poor weld and making it difficult to meet the overcurrent requirements.

[0089] The above-mentioned numerical range not only meets the overcurrent requirements, but also does not easily generate heat or cause overheating defects; the current required during welding is appropriate, and it is easy to form a good solder mark.

[0090] The number n of welded joints 4 is greater than or equal to 2 and less than or equal to 9. For example, the number n of welded joints 4 can be 3, 4, 5, 6, 7, or 8.

[0091] The number n of welded joints 4 and the weld area s are mutually restrictive. For example, when the number n of welded joints 4 is too large, the welding current is constant, resulting in a large number of current shunts. Consequently, the current distributed to each welded joint 4 is small, leading to a slower growth trend of the weld nugget at each welded joint 4 and making it difficult to form a large weld area. Conversely, when the number n of welded joints 4 is too small, the number of current shunts is small, resulting in a larger current distributed to each welded joint 4. This causes the weld nugget to grow faster at each welded joint 4, making it easier to form a large weld area. Therefore, it is necessary to limit the ratio of the number n of welded joints 4 to the weld area s.

[0092] Based on the same inventive concept, this disclosure provides an example embodiment of a battery device, which may include a battery case and a battery; the battery is any of the batteries described above, and the battery is disposed inside the battery case. The specific structure of the battery has been described in detail above, and therefore will not be repeated here.

[0093] In this example embodiment, the battery device may include a battery case, which may be configured as a cuboid structure; therefore, the battery case may also be configured as a cuboid structure. Specifically, the battery case may include a support plate, a protective cover, two first side frames, and two second side frames. The support plate and the protective cover may be rectangular. Two first side frames and two second side frames are provided around the support plate, connected end-to-end to form a rectangular frame. The first side frames extend along the width direction, and the second side frames extend along the length direction. A protective cover is provided on the opposite side of the two first side frames and two second side frames from the support plate, such that the protective cover is positioned opposite the support plate. The two first side frames and two second side frames are connected between the protective cover and the support plate. The support plate, the protective cover, the two first side frames, and the two second side frames surround and form the receiving cavity of the battery case.

[0094] Of course, in other exemplary embodiments of this disclosure, the support plate and protective cover can be circular, elliptical, trapezoidal, etc., and the side frame can be one or more, forming a circle, ellipse, trapezoid, etc., so that the battery box is formed as a cylinder, elliptical cylinder, prism, etc. In other embodiments, there may be no protective cover, and the battery box can be directly assembled to the vehicle chassis. The battery box can also be other shapes, which will not be described in detail here.

[0095] The battery device disclosed herein ensures, on the one hand, that the welding heat required during welding is moderate, the melting area of ​​the tab 32 is moderate, and the tab 32 and the welding head are not easily stuck together, thereby ensuring welding quality and avoiding high resistance after welding that would affect the overcurrent, thus ensuring the electrical performance of the battery; and also avoids affecting the service life of the welding head; on the other hand, it ensures that the overcurrent area between the terminal assembly 2 and the tab 32 is appropriate, avoiding excessive heat generation during battery charging and discharging, avoiding the safety risk of thermal runaway, thus ensuring the safety performance of the battery device.

[0096] The terms "parallel" and "perpendicular" used in this application can mean not only perfectly parallel and perpendicular, but also have a certain margin of error; for example, if the angle between the two is greater than or equal to 0° and less than or equal to 5°, they are considered to be parallel; if the angle between the two is greater than or equal to 85° and less than or equal to 95°, they are considered to be perpendicular.

[0097] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the utility models disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

Claims

1. A battery, characterized by, include: pole assembly; The battery cell includes the main body and the electrode tabs; At least two welded connections are provided, connecting the tab and the pole assembly. The weld area connecting the welded connection to the tab is s, the number of welded connections is n, and the ratio of the number of welded connections n to the weld area s, n / s, is greater than or equal to 0.15 mm. -2 Less than or equal to 10.5mm -2 .

2. The battery of claim 1, wherein, The connection area between the welded joint and the pole assembly is m, and the ratio of the weld area s to the connection area m, s / m, is greater than or equal to 0.5 and less than or equal to 0.

9.

3. The battery according to claim 1, characterized in that, The material of the electrode ear includes copper.

4. The battery of claim 1, wherein, The material of the tab portion includes aluminum, and a ratio n / s of the number n of the welding connection portions to the welding mark area s is greater than or equal to 0.15 mm -2 less than or equal to 9.8 mm -2 .

5. The battery of claim 1, wherein, The height h of the portion of the welded connection located between the pole post assembly and the pole lug is greater than or equal to 0.2 mm and less than or equal to 1.5 mm.

6. The battery of claim 1, wherein, The welded joints are configured as at least three, and the at least three welded joints are arranged in at least one triangle; or, the welded joints are configured as at least four, and the at least four welded joints are arranged in at least one quadrilateral; or, a plurality of the welded joints are arranged in a straight line.

7. The battery of claim 1, wherein, The minimum spacing k between two adjacent welded joints is greater than or equal to 1 mm and less than or equal to 5 mm.

8. The battery of claim 1, wherein, The shape of the orthographic projection of the welded connection on the first reference plane is circular, and the first reference plane is parallel to the side of the pole assembly that connects to the pole lug.

9. The battery of claim 2, wherein, The connection area m of the welding connection part connected with the pole assembly is greater than or equal to 0.75 mm 2 Less than or equal to 40 mm 2 .

10. A battery device characterized by comprising: include: Battery box; The battery is the battery according to any one of claims 1 to 9, and the battery is disposed inside the battery case.

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