Electrode assembly, battery, and electric device

Abstract

The utility model relates to an electrode assembly, battery and electric device, include: electric core body, have first electric core end face and first electric core big face, the ear root department of ear bundle has the first ear surface and second ear surface, the ear root department connects first electric core end face, electric connecting piece connects second ear surface and forms the welding mark, insulating adhesive piece includes the first length direction of insulating adhesive piece first edge long direction is connected in proper order first section, second section, third section, fourth section and fifth section, first section sticks first electric core big face, third section sticks the ear area between ear root department and welding mark, fifth section sticks the ear area of one side of welding mark far from ear root department, and the size of fourth section along the first length direction of insulating adhesive piece first edge long direction is greater than the size of welding mark along the first length direction of ear bundle first edge long direction. The utility model avoids the ear crack caused by the edge of welding mark being pulled by insulating adhesive piece.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to an electrode assembly, a battery, and an electrical device. Background Technology

[0002] In the manufacturing process of lithium batteries, the tab welding process is extremely important, as it directly affects the battery's electrical performance. Currently, the mainstream battery design is a multi-tab structure, which is welded to the cover plate electrical connectors by ultrasonic welding. After welding, adhesive is often applied to the tabs to prevent welding dust from falling off and to protect the electrode sheets.

[0003] In the actual manufacturing process, the tape and the electrode tab do not adhere well, such as... Figure 1 As shown, one end of the insulating adhesive 11 is attached to the large surface 121 of the cell body 12, and the other end of the tape 11 is attached to the weld mark 131 formed by welding the tab 13 and the electrical connector 14. The middle section 111 of the tape 11 is stretched diagonally and is not attached to the root 132 of the tab 13. After the cell undergoes transportation, flexible connection welding, and other operations, the tape is prone to pulling on the edge of the weld mark, causing the tab to crack, which in turn leads to problems such as low cell capacity and lithium plating. How to prevent the tab from cracking is a technical problem that urgently needs to be solved in this field. Utility Model Content

[0004] Therefore, this utility model provides an electrode assembly that avoids the electrode tab cracking caused by the insulating adhesive pulling on the edge of the solder mark.

[0005] To solve the above-mentioned technical problems, this utility model provides an electrode assembly, comprising: The cell body has a first cell end face for leading out the electrode tabs and a first cell large face located on one side in its thickness direction; The electrode bundle has an electrode root located at one end in the first side length direction, a first electrode surface located on one side in the thickness direction, and a second electrode surface located on the other side in the thickness direction, wherein the electrode root is connected to the end face of the first cell. An electrical connector is attached to the surface of the second electrode tab and a solder mark is formed thereon. An insulating adhesive component includes a first segment, a second segment, a third segment, a fourth segment, and a fifth segment connected sequentially along the first side length direction of the insulating adhesive component. The first segment is bonded to the large surface of the first battery cell, and the area where the two are bonded is the first adhesive printing area. The third segment is bonded to the tab area between the root of the electrode and the solder mark, and the area where the two are bonded is the third adhesive printing area. The fifth segment is bonded to the tab area on the side of the solder mark away from the root of the electrode, and the area where the two are bonded is the fifth adhesive printing area. The dimension of the fourth segment along the first side length direction of the insulating adhesive component is larger than the dimension of the solder mark along the first side length direction of the tab bundle.

[0006] Furthermore, the difference between the dimension of the fourth segment along the first side length direction of the insulating adhesive and the dimension of the solder mark along the first side length direction of the tab bundle is 1-3 mm.

[0007] Furthermore, the fourth segment arches away from the solder mark.

[0008] Furthermore, the distance between the fourth segment and the solder mark is not less than 1 mm.

[0009] Furthermore, at least a portion of the fourth segment contacts the solder mark to form a fourth offset printing area, and at least a portion of the fourth segment adheres to each other to form an overlapping portion.

[0010] Furthermore, the distance between the edge of the third offset printing area near the solder mark and the edge of the solder mark near the third offset printing area is not less than 3 mm; and / or, The distance between the edge of the third offset printing area near the root of the tab and the root of the tab is no more than 1 mm.

[0011] Furthermore, the dimensions of the third offset printing area and the fifth offset printing area along the first side length direction of the insulating adhesive are 2-3 mm.

[0012] Furthermore, the second section is bonded to the end face of the first battery cell to form a second offset printing area.

[0013] This utility model also provides a battery, including the electrode assembly described above.

[0014] This utility model also provides an electrical device, including the aforementioned battery.

[0015] Compared with the prior art, the above-mentioned technical solution of this utility model has the following advantages: In the electrode assembly, battery and power device of this utility model, the insulating adhesive does not contact the solder mark, and is arched relative to the solder mark. Moreover, the contact point between the insulating adhesive and the electrode bundle is close to the root of the electrode and far from the edge of the solder mark, which can avoid the insulating adhesive from deforming under force and pulling the edge of the solder mark, thus causing the solder mark to crack. Attached Figure Description

[0016] To make the content of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0017] Figure 1 This is a schematic diagram of an electrode assembly in the prior art; Figure 2 This is a schematic diagram of the electrode assembly in this utility model; Figure 3 This is a schematic diagram of the insulating adhesive component under tension in this utility model.

[0018] Instruction manual drawing references: 11. Tape; 111. Middle section; 12. Battery cell body; 121. Large surface; 13. Electrode tab; 131. Solder mark; 132. Root; 14. Electrical connector; 21. Battery cell body; 211. First battery cell end face; 212. First battery cell large face; 22. Electrode bundle; 221. Electrode root; 222. First electrode surface; 223. Second electrode surface; 224. Solder mark; 23. Electrical connector; 24. Insulating adhesive; 241. First segment; 242. Second segment; 243. Third segment; 244. Fourth segment; 245. Fifth segment. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments are not intended to limit the present invention.

[0020] See Figure 2 and Figure 3 As shown, this invention provides an embodiment of an electrode assembly.

[0021] The electrode assembly includes: The cell body 21 has a first cell end face 211 for leading out the electrode tab and a first cell large face 212 located on one side in its thickness direction; The electrode bundle 22 has an electrode root 221 located at one end of its first side length direction, a first electrode surface 222 located on one side of its thickness direction, and a second electrode surface 223 located on the other side of its thickness direction. The electrode root 221 is connected to the first cell end face 211. Electrical connector 23 connects to the surface 223 of the second electrode and forms a solder mark 224; The insulating adhesive 24 includes a first segment 241, a second segment 242, a third segment 243, a fourth segment 244, and a fifth segment 245 connected sequentially along the first side length direction of the insulating adhesive. The first segment 241 is bonded to the large surface 212 of the first battery cell, and the area where the two are bonded is the first adhesive area. The third segment 243 is bonded to the tab area between the tab root 221 and the solder mark 224, and the area where the two are bonded is the third adhesive area. The fifth segment 245 is bonded to the tab area on the side of the solder mark 224 away from the tab root 221, and the area where the two are bonded is the fifth adhesive area. The dimension of the fourth segment 244 along the first side length direction of the insulating adhesive 24 is larger than the dimension of the solder mark 224 along the first side length direction of the tab bundle 22.

[0022] In the above text, the battery cell body 21 is mainly formed by stacking or rolling and flattening positive electrode plates, negative electrode plates, and separators. When the positive electrode plates, negative electrode plates, and separators are stacked, the two outermost layers are generally separators. The first large surface 212 of the battery cell refers to one of the separator surfaces facing the outside of the battery cell body 21 after the battery cell body 21 is formed. The first end face 211 of the battery cell refers to one of the surfaces formed by the sides of the stacked positive electrode plates, negative electrode plates, and separators. The tab bundle 22 is mainly formed by stacking multiple layers of tab plates. The first tab surface 222 and the second tab surface 223 are the two tab surfaces of the tab bundle 22 facing the outside of the tab bundle 22. The tab root 221 refers to the part of the tab bundle 22 that connects to the first end face 211 of the battery cell. Electrical connector 23 is used to connect the positive or negative terminal of the same electrode assembly and connect to the battery terminal, thereby realizing the external electrical connection of the electrode assembly. Generally, electrical connector 23 is connected to the tab bundle 22 by welding. The joint area formed by welding electrical connector 23 and tab bundle 22 is called solder mark 224. Solder residue is easy to remain on solder mark 224. In order to prevent solder residue on solder mark 224 from falling onto the first cell end face 211 of cell body 21, insulating parts are bonded to the first cell large surface 212 of cell body 21 and the first tab surface 222 of tab bundle 22. The insulating parts generally have their own adhesive backing, that is, the insulating parts are generally insulating adhesive parts 24, such as tape. The insulating adhesive 24 is a long strip. The first side of the insulating adhesive 24 is generally its length direction. The first segment 241 of the insulating adhesive 24 is opposite to the first large surface 212 of the battery cell body 21. The second segment 242 of the insulating adhesive 24 is opposite to the first end face 211 of the battery cell body 21. The third segment 243, the fourth segment 244 and the fifth segment 245 of the insulating adhesive 24 are opposite to the first tab surface 222 of the tab bundle 22. The first segment 241, the second segment 242, the third segment 243 and the fifth segment 245 are all in a taut state, while the fourth segment 244 is in a slack state.

[0023] Specifically, the insulating adhesive 24 is relatively fixed to the battery cell body 21 through the first segment 241, the fixation of the third segment 243 near the root of the tab 221 can suppress the root swing of the tab bundle, the fixation of the fifth segment 245 on the outside of the solder mark can prevent the end of the solder mark from lifting, and the fourth segment 244 is not bonded to the solder mark 224. The excess length forms a non-tight state in the area of ​​the solder mark 224. When the external force is transmitted to the fourth segment 244 of the insulating adhesive 24, the excess length allows the insulating adhesive 24 to undergo moderate deformation, avoiding direct pulling on the edge of the solder mark.

[0024] With the above technical solution, the insulating adhesive does not contact the solder mark, but is arched relative to the solder mark. The contact point between the insulating adhesive and the tab bundle is close to the root of the tab and far from the edge of the solder mark. This can prevent the insulating adhesive from deforming under force and pulling the edge of the solder mark, which would cause the solder mark to crack.

[0025] In this embodiment, the difference between the dimension of the fourth segment 244 along the first side length direction of the insulating adhesive 24 and the dimension of the solder mark 224 along the first side length direction of the tab bundle 22 is 1-3 mm.

[0026] In the above text, the difference between the dimension of the fourth segment 244 along the first side length direction of the insulating adhesive 24 and the dimension of the solder mark 224 along the first side length direction of the tab bundle 22 determines the degree of arching of the fourth segment 244.

[0027] Specifically, the greater the difference between the dimension of the fourth segment 244 along the first side length of the insulating adhesive 24 and the dimension of the solder mark 224 along the first side length of the tab bundle 22, the greater the arch height H1; conversely, the smaller the difference, the smaller the arch height H1. This difference is 1-3 mm, specifically 1 mm, 2 mm, or 3 mm. This difference is neither too large, preventing the fourth segment 244 from arching and occupying too much space, thus avoiding material waste, nor too small, preventing the distance between the fourth segment 244 and the solder mark 224 from being too small, which could lead to them easily sticking together.

[0028] The above technical solution controls the difference in size between the fourth section of the insulating adhesive and the solder mark within a certain range, preventing material waste and excessive space occupation, and ensuring that the insulating adhesive and the solder mark do not come into contact with each other.

[0029] In this embodiment, the fourth segment 244 arches away from the solder mark 224.

[0030] In the above text, the fourth segment 244 of the insulating adhesive 24 arches away from the solder mark, which means that the fourth segment 244 of the insulating adhesive 24 is arched, and the concave side of the fourth segment 244 of the insulating adhesive 24 faces the solder mark 224.

[0031] Specifically, when the insulating adhesive 24 is attached to the cell body 21 and the tab bundle 22, if the fourth segment 244 of the insulating adhesive 24 arches towards the solder mark 224, the insulating adhesive 24 will be attached to the solder mark 224 during the pasting process. If the fourth segment 244 is deformed under force during the pasting process, it will cause the solder mark 224 to be pulled.

[0032] With the above solution, the insulating adhesive does not come into contact with the solder joint during the bonding process, thereby preventing the insulating adhesive from pulling on the solder joint during the bonding process.

[0033] In this embodiment, the distance between the fourth segment 244 and the solder mark 224 is not less than 1 mm.

[0034] In the above text, the distance between the fourth segment 244 and the solder mark 224 is the arch height of the fourth segment 244. For example, it can be 1 mm, 1.5 mm, 2 mm, 2.5 mm or 3 mm.

[0035] Specifically, the arch height of the fourth segment 244 should not be too large or too small. If it is too large, the fourth segment 244 will occupy a lot of space and cause material waste. If it is too small, the fourth segment 244 will easily stick to the solder stamp 224, causing it to be pulled.

[0036] Through the above technical solution, a certain distance is maintained between the fourth segment of the insulating adhesive and the solder mark, ensuring that the insulating adhesive will not pull on the solder mark when it is deformed by force.

[0037] In this embodiment, at least a portion of the fourth segment 244 contacts the solder mark 224 to form a fourth offset printing area, and at least a portion of the fourth segment adheres to each other to form the overlapping portion.

[0038] In the above text, the two ends of the fourth segment 244 of the insulating adhesive 24 are bonded to the tab bundle 22. The middle part of the fourth segment 244 arches towards the side where the solder mark 224 is located, so that the fourth segment 244 forms a W-shaped shape. The parts on both sides of the bending position of the fourth segment 244 will be bonded together to form an overlapping part due to the bonding surfaces being opposite. This overlapping part is not easy to bond with the solder mark 224.

[0039] Specifically, during the electrode assembly adhesive application process, the two cell bodies 21 are laid flat, and the tab bundle 22 is in a straight state. After the adhesive application is completed, the cells need to be joined together. During the joining process, the two cell bodies 21 are stacked together, and the tab bundle 22 is deformed from a straight state to a bent state. At this time, due to the redundancy of the insulating adhesive 24, the fourth segment 244 is deformed from an arched state away from the solder mark 224 during adhesive application to a partial arched state closer to the solder mark 224, thus forming the aforementioned W shape and overlapping part.

[0040] With the above technical solution, when the electrode assembly is assembled, the insulating adhesive will not cause the solder to be pulled when it is deformed by force.

[0041] In this embodiment, the distance between the edge of the third offset printing area near the solder mark 224 and the edge of the solder mark 224 near the third offset printing area is not less than 3 mm; and / or, The distance between the edge of the third offset printing area near the root of the tab and the root of the tab 221 is no more than 1 mm.

[0042] In the above text, the third offset printing area is located between the tab root 221 and the solder mark 224. The distance L3 between the opposite edges of the third offset printing and the solder mark 224 is not less than 3 mm, for example, it can be 3 mm, 4 mm or 5 mm. The distance L2 between the opposite edges of the third offset printing and the tab root 221 is not greater than 1 mm, for example, it can be 1 mm, 0.5 mm, or the third segment 243 is directly bonded to the tab root 221.

[0043] Specifically, the smaller the distance between the third offset printing area and the solder mark 224, the easier it is for the insulating adhesive 24 to pull the solder mark 224; the larger the distance between the third offset printing area and the solder mark 224, the less likely the insulating adhesive 24 is to pull the solder mark 224. Where the size allows, the distance between the third offset printing area and the solder mark 224 should be as large as possible.

[0044] The smaller the distance between the third offset printing area and the base 221 of the tab, the better the insulating adhesive 24 can position the base of the tab; conversely, the larger the distance between the third offset printing area and the base 221 of the tab, the less effective the insulating adhesive 24 is at positioning the base of the tab. The distance between the third offset printing area and the base 221 of the tab should be as small as possible.

[0045] Through the above technical solution, the distance between the third offset printing area and the solder stamp is as large as possible, and the distance between the third offset printing area and the root of the electrode tab is as small as possible, so as to prevent the solder stamp from being pulled and at the same time ensure effective fixation of the root of the electrode tab.

[0046] In this embodiment, the dimensions of the third offset printing area and the fifth offset printing area along the first side length direction of the insulating adhesive 24 are 2-3 mm.

[0047] In the above text, the dimension of the third offset printing area along the first side length of the insulating adhesive 24 is the connection dimension between the third segment 243 of the insulating adhesive 24 and the tab bundle 22. Specifically, it can be 2 mm, 2.5 mm, or 3 mm. The dimension of the fifth offset printing area along the first side length of the insulating adhesive 24 is the connection dimension between the fifth segment 245 of the insulating adhesive 24 and the tab bundle 22. Specifically, it can be 2 mm, 2.5 mm, or 3 mm.

[0048] Specifically, the connection dimensions between the third segment 243 and the fifth segment 245 and the tab bundle 22 should be neither too large nor too small. If they are too large, the fit between the insulating adhesive 24 and the tab bundle 22 will be poor. If they are too small, the bonding strength between the insulating adhesive 24 and the tab bundle 22 will be insufficient.

[0049] Through the above technical solution, the dimensions of the third offset printing area and the fifth offset printing area are limited to a certain range, which ensures both the fit between the insulating adhesive and the tab bundle and the bonding strength between the insulating adhesive and the tab bundle.

[0050] In this embodiment, the second segment 242 is bonded to the end face 211 of the first battery cell to form a second offset printing area.

[0051] In the above text, the second segment 242 refers to the transition area between the first segment 241 and the third segment 243 in the insulating adhesive 24, and the second offset area refers to the fixed area formed between the second segment and the end face of the battery cell by the adhesive.

[0052] Specifically, when the third segment 243 of the insulating adhesive 24 is bonded to the root of the electrode tab 221, both ends of the second segment 242 are close to the first cell end face 211 of the cell body 21. Therefore, the insulating adhesive 24 can be directly bonded to the first cell end face. Thus, most of the insulating adhesive 24 is fixed together with the electrode assembly, and the insulating adhesive 24 is not easily deformed.

[0053] By using the above technical solutions, the suspended portion of the insulating adhesive is reduced, making the insulating adhesive less prone to deformation under stress, and thus less prone to pulling the solder marks.

[0054] The following describes a battery that includes the electrode assembly described above.

[0055] In the above text, a battery can be a single battery cell or a battery module that combines multiple battery cells. A single battery cell is the basic unit that realizes the interconversion of chemical energy and electrical energy. In addition to the electrode assembly mentioned above, it also includes a casing, electrolyte, and terminals. The electrode assembly is located inside the casing, the electrolyte is injected into the casing, and the terminals are mounted on the cover plate of the casing and connected to the electrical connectors mentioned above.

[0056] The following describes an electrical device, which includes the battery described above.

[0057] In the above description, the battery is used in an electrical device to supply power. The electrical device can be a car, ship, airplane, drone, spacecraft, electric toy, power tool, laptop, tablet, mobile phone, or other portable device. Cars can be gasoline-powered, natural gas-powered, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles. Spacecraft include rockets, space shuttles, and spacecraft. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers. This application does not impose any special limitations on the above-mentioned electrical devices.

[0058] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. An electrode assembly, characterized in that, include: The cell body (21) has a first cell end face (211) for leading out the electrode tab and a first cell large face (212) located on one side in its thickness direction. The electrode bundle (22) has an electrode root (221) located at one end of its first side length direction, a first electrode surface (222) located on one side of its thickness direction, and a second electrode surface (223) located on the other side of its thickness direction. The electrode root (221) is connected to the first cell end face (211). Electrical connector (23) connects to the surface of the second electrode tab (223) and forms a solder mark (224); The insulating adhesive (24) includes a first segment (241), a second segment (242), a third segment (243), a fourth segment (244), and a fifth segment (245) connected sequentially along the first side length direction of the insulating adhesive. The first segment (241) is bonded to the large surface (212) of the first battery cell, and the area where the two are bonded is the first offset printing area. The third segment (243) is bonded to the tab area between the tab root (221) and the solder mark (224), and the area where the two are bonded is the third offset printing area. The fifth segment (245) is bonded to the tab area on the side of the solder mark (224) away from the tab root (221), and the area where the two are bonded is the fifth offset printing area. The dimension of the fourth segment (244) along the first side length direction of the insulating adhesive (24) is greater than the dimension of the solder mark (224) along the first side length direction of the tab bundle (22).

2. The electrode assembly according to claim 1, characterized in that, The difference between the dimension of the fourth segment (244) along the first side length direction of the insulating adhesive (24) and the dimension of the solder mark (224) along the first side length direction of the tab bundle (22) is 1-3 mm.

3. The electrode assembly according to claim 1, characterized in that, The fourth segment (244) arches away from the solder mark (224).

4. The electrode assembly according to claim 3, characterized in that, The distance between the fourth segment (244) and the solder mark (224) is not less than 1 mm.

5. The electrode assembly according to claim 1, characterized in that, The fourth segment (244) is at least partially in contact with the solder mark (224) to form a fourth offset printing area, and the fourth segments are at least partially bonded to each other to form an overlapping portion.

6. The electrode assembly according to claim 1, characterized in that, The distance between the edge of the third offset printing area near the solder mark and the edge of the solder mark (224) near the third offset printing area is not less than 3 mm; and / or, The distance between the edge of the third offset printing area near the root of the tab and the root of the tab (221) is no greater than 1 mm.

7. The electrode assembly according to claim 1, characterized in that, The dimensions of the third and fifth offset printing areas along the first side length direction of the insulating adhesive (24) are 2-3 mm.

8. The electrode assembly according to claim 1, characterized in that, The second segment (242) is bonded to the end face (211) of the first battery cell to form a second offset printing area.

9. A battery, characterized in that, Includes the electrode assembly as described in any one of claims 1 to 8.

10. An electrical appliance, characterized in that, Includes the battery as described in claim 9.

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