Battery pole group and battery

Abstract

The invention belongs to the technical field of batteries, and discloses a battery pole group and a battery. The battery pole group comprises a pole group main body and a pole lug body, the pole group main body comprises an expansion pole body and a butt-joint pole body, the cross section area of the butt-joint pole body is smaller than that of the expansion pole body, the butt-joint pole body is connected to the two sides of the expansion pole body, and a conductive coating is coated between the end faces, making contact with the expansion pole body, of the butt-joint pole body. A protective boss is arranged on one side, deviating from the capacity expansion pole body, of the butt-joint pole body, the tab bodies are connected to the end face, provided with the protective boss, of the butt-joint pole body, a conductive coating is coated between the end faces, making contact with the butt-joint pole body, of the tab bodies, the tab bodies are located on the two sides of the protective boss, and the height, in the first direction, of the tab bodies is smaller than the protruding height of the protective boss. According to the battery pole group, the overall size of the battery pole group is increased and the capacity is improved by increasing the size of the capacity expansion pole body and additionally arranging the protection boss, and the protection on the pole lug body is realized by utilizing the protection boss. In addition, the plurality of tab bodies are arranged, so that the overcurrent capability is improved.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and more particularly to a battery electrode assembly and a battery. Background Technology

[0002] With the rapid development of new energy vehicles, energy storage systems, and other fields, the market is placing increasingly higher demands on the energy density, safety, charge-discharge performance, and lifespan of power batteries. As a core component of power batteries, the structural design of the battery electrode assembly directly affects the overall performance of the battery. Within the limited space of the battery casing, how to improve energy density, enhance current conduction efficiency, and strengthen the structural stability of the electrode assembly during assembly by optimizing its structure has become one of the key research directions in the industry.

[0003] Traditional battery electrode assemblies typically employ a regular stacked or wound structure, forming a regular cuboid or cylinder. The multi-layered conductive tabs are integrated into a single unit, positioned on the same plane, and are generally directly connected to the terminal posts or connecting tabs on the battery cover using methods such as laser welding. During assembly, the thrust is often applied directly to the end face where the conductive tabs are located or the edge of the electrode assembly, relying on the structural strength of the electrode assembly itself to withstand the pressure during assembly.

[0004] However, traditional battery electrode packs have several limitations: First, traditional electrode packs typically have only one tab of the same polarity, resulting in a limited overcurrent area. This can lead to excessively high current density during high-current charging and discharging, increasing overcurrent temperature, affecting battery cycle performance, and potentially causing safety hazards due to localized overheating. Second, due to the lack of a dedicated support structure, the thrust applied when the electrode pack is installed into the casing acts directly on the tabs or the area near them. The tabs are easily deformed or broken due to compression, or the weld between the tabs and the cover plate may become faulty or detached, affecting the battery's conductivity and sealing. Third, to avoid structural interference, traditional electrode packs often need to compress their own volume, making it difficult to fully utilize the space within the battery casing and limiting further increases in battery capacity. Summary of the Invention

[0005] The purpose of this invention is to provide a battery electrode assembly and battery with a large overcurrent area, low overcurrent temperature, good protection, large size, and high capacity.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] On one hand, a battery electrode assembly is provided, the battery electrode assembly comprising:

[0008] The electrode assembly body includes an expansion electrode and a docking electrode. The cross-sectional area of ​​the docking electrode perpendicular to the first direction is smaller than the cross-sectional area of ​​the expansion electrode perpendicular to the first direction. The docking electrode is connected to both sides of the expansion electrode along the first direction, and a conductive coating is applied between the end faces of the docking electrode and the expansion electrode that are in contact. The docking electrode has a protective protrusion extending in a direction away from the expansion electrode on the side away from the expansion electrode.

[0009] The electrode body is connected to the end face of the docking electrode body where the protective boss is provided, and the conductive coating is coated between the end faces of the electrode body and the docking electrode body that are in contact. The electrode body is located on both sides of the protective boss, and the height of the electrode body along the first direction is less than the height of the protective boss protrusion.

[0010] Optionally, the expansion electrode includes a first end and a second end along the second direction. The end face of the expansion electrode connected to the docking electrode is provided with a mounting boss extending from the first end to the second end. A docking groove is formed on the mounting boss. The end face of the docking electrode facing the expansion electrode is provided with a docking boss. The docking boss is inserted into the docking groove. The projection range of the docking electrode on the expansion electrode along the first direction does not exceed the mounting boss.

[0011] Optionally, the distance between the end face of the protective protrusion away from the expansion electrode and the end face of the docking electrode where the docking protrusion is provided along the first direction is E1, and the length of the first end along the first direction is E2, and satisfies 1≤E2 / E1≤1.5.

[0012] Optionally, the width dimension of the docking electrode along the third direction is B1, and the width dimension of the expansion electrode along the third direction is B2, and satisfies 16mm≤B2-B1≤60mm.

[0013] Optionally, the height dimension of the docking electrode along the second direction is A1, and the height dimension of the expansion electrode along the second direction is A2, and the height satisfies 20mm≤A2-A1≤80mm.

[0014] Optionally, the height dimension of the protective boss along the second direction is W1, and the ratio between the height dimension W1 of the protective boss along the second direction and the height dimension A1 of the docking electrode along the second direction satisfies 0.33≤W1 / A1≤0.6.

[0015] Optionally, the tab body includes a tab base and a plurality of connecting tabs. The plurality of connecting tabs are connected to the side of the tab base away from the conductive coating. The tab base has a plugging boss on the side facing the protective boss. The protective boss has a plugging groove on the end face facing the tab body. The plugging boss is inserted into the plugging groove.

[0016] The distance between the two insertion grooves along the second direction is W2, and the difference between the height W1 of the protective boss along the second direction and the distance W2 between the two insertion grooves along the second direction satisfies 14mm≤W1-W2≤40mm.

[0017] Optionally, the insertion groove includes an abutting arc surface, two first limiting inclined surfaces, and two second limiting inclined surfaces. The two first limiting inclined surfaces are connected to both sides of the abutting arc surface along the third direction and are inclined in a direction that approaches each other. The two second limiting inclined surfaces are connected to one end of the first limiting inclined surface away from the abutting arc surface and are inclined in a direction that moves away from each other, so as to form a limiting boss in the insertion groove.

[0018] Optionally, the mating electrode body has a mounting groove on the end face of the protective boss. The mounting groove is located on both sides of the protective boss along a third direction and has a connecting plane, a connecting slope, and an abutting plane. The connecting plane has inclined connecting slopes on both sides along a second direction and is connected to the lower end of the connecting slope. The abutting plane is parallel to the connecting plane and is connected to the higher end of the connecting slope. The electrode body includes a first electrode body and a second electrode body. The first electrode body is disposed on the connecting plane, and the second electrode body is connected to both sides of the first electrode body and disposed on the corresponding connecting slope.

[0019] On the other hand, a battery is provided, the battery including a battery cover, a battery housing and a battery electrode assembly as described in any of the above claims, the battery housing being a hollow housing structure with an opening, the battery cover being disposed at the opening of the battery housing to close the battery housing and to form a closed cavity for accommodating the battery electrode assembly.

[0020] The beneficial effects of this invention are:

[0021] This invention provides a battery electrode assembly, comprising an expansion electrode and a docking electrode. By increasing the cross-sectional area of ​​the expansion electrode to be larger than that of the docking electrode, the volume of the expansion electrode is increased. Furthermore, a protective protrusion is provided on the docking electrode, thereby increasing the overall volume of the battery electrode assembly and improving its capacity. Since the height of the protective protrusion is greater than the height of the tabs connected to the docking electrode, the thrust is applied to the protective protrusion when the battery electrode assembly is installed in the casing, avoiding direct force on the tabs and providing good protection. This reduces the occurrence of problems such as tab deformation and breakage. In addition, since tabs are provided on both sides of the protective protrusion, the current-carrying area of ​​the tabs is effectively increased, and the temperature during the current-carrying process is reduced, improving the battery's charging and discharging performance and safety.

[0022] The present invention also provides a battery that, by applying the above-described battery electrode assembly, not only reduces the risk of safety problems caused by overheating, but also increases the battery capacity, meets the demand for improved battery energy density, and thus has a longer driving range or a longer power supply time. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the battery electrode assembly in Embodiment 1 provided by the present invention;

[0024] Figure 2 This is a structural exploded view of one side of the battery electrode assembly in Embodiment 1 of the present invention;

[0025] Figure 3 This is a structural exploded view of the other side of the battery electrode assembly in Embodiment 1 of the present invention;

[0026] Figure 4 This is a cross-sectional view of the battery electrode assembly in Embodiment 1 of the present invention;

[0027] Figure 5 This is a top view of the battery electrode assembly in Embodiment 1 provided by the present invention;

[0028] Figure 6 This is a schematic diagram of the structure of the docking electrode of the battery electrode assembly in Embodiment 1 of the present invention;

[0029] Figure 7 This is a side view of the docking electrode of the battery electrode assembly in Embodiment 1 of the present invention;

[0030] Figure 8 This is a schematic diagram of the structure of the electrode tab of the battery electrode assembly in Embodiment 1 of the present invention;

[0031] Figure 9 This is a schematic diagram of the battery electrode assembly in Embodiment 2 of the present invention.

[0032] In the picture:

[0033] 1. Electrode assembly body; 11. Expanded electrode body; 111. First end; 112. Second end; 113. Mounting boss; 114. Docking groove; 12. Docking electrode body; 121. Protective boss; 122. Docking boss; 123. Insertion groove; 1231. Abutting arc surface; 1232. First limiting slope; 1233. Second limiting slope; 1234. Limiting boss; 124. Mounting groove; 1241. Connecting plane; 1242. Connecting slope; 1243. Abutting plane; 13. Guide groove;

[0034] 2. Electrode body; 21. Electrode base; 22. Connecting electrode; 23. Insertion boss; 24. First electrode body; 25. Second electrode body;

[0035] 3. Positive conductive coating;

[0036] 4. Negative electrode conductive coating. Detailed Implementation

[0037] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0038] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0039] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0040] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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 the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0041] Traditional battery electrode packs have several limitations: First, they typically have only one tab of the same polarity, resulting in a limited overcurrent area. This can lead to excessively high current density during high-current charging and discharging, increasing overcurrent temperature, affecting battery cycle performance, and potentially causing safety hazards due to localized overheating. Second, due to the lack of a dedicated support structure, the thrust applied when the battery pack is installed directly acts on the tab or the area near it. This can cause the tab to deform or break under pressure, or result in incomplete or detached welding at the connection between the tab and the cover plate, affecting the battery's conductivity and sealing. Third, to avoid structural interference, traditional electrode packs often need to compress their own volume, making it difficult to fully utilize the space within the battery casing and limiting further increases in battery capacity.

[0042] Therefore, in order to increase the current-carrying area of ​​the battery electrode assembly, reduce the temperature during the current flow process, improve the protection of the tabs, increase the volume of the electrode assembly, and increase the capacity, this embodiment provides a battery electrode assembly. For ease of description, the length direction of the battery electrode assembly is defined as the first direction, the height direction as the second direction, and the width direction as the third direction.

[0043] Example 1

[0044] like Figures 1 to 8 As shown, the battery electrode assembly includes an electrode assembly body 1 and a tab body 2. The electrode assembly body 1 includes an expansion electrode 11 and a docking electrode 12. The cross-sectional area of ​​the docking electrode 12 perpendicular to the first direction is smaller than the cross-sectional area of ​​the expansion electrode 11 perpendicular to the first direction. The docking electrode 12 is connected to both sides of the expansion electrode 11 along the first direction, and a conductive coating is applied between the end faces of the docking electrode 12 and the expansion electrode 11 that are in contact. The docking electrode 12 has a protective protrusion 121 extending in a direction away from the expansion electrode 11 on the side away from the expansion electrode 11. The tab body 2 is connected to the end face of the docking electrode 12 with the protective protrusion 121, and a conductive coating is applied between the end faces of the tab body 2 and the docking electrode 12 that are in contact. The tab body 2 is located on both sides of the protective protrusion 121, and the height of the tab body 2 along the first direction is smaller than the height of the protrusion of the protective protrusion 121.

[0045] The battery assembly body 1, composed of an expansion electrode 11 and a docking electrode 12, increases the volume of the expansion electrode 11 by making its cross-sectional area larger than that of the docking electrode 12. A protective protrusion 121 is also provided on the docking electrode 12, thereby increasing the overall volume of the battery assembly and improving its capacity. Furthermore, since the height of the protective protrusion 121 is greater than the height of the tab 2 connected to the docking electrode 12, the thrust is applied to the protective protrusion 121 when the battery assembly is inserted into the casing, avoiding direct force on the tab 2 and providing good protection for it. This reduces the occurrence of deformation and breakage of the tab 2. In addition, since tabs 2 are provided on both sides of the protective protrusion 121, the current-carrying area of ​​the tab 2 is effectively increased, and the temperature during the current-carrying process is reduced, improving the battery's charging and discharging performance and safety.

[0046] In this embodiment, the expansion electrode 11 and the docking electrode 12 constituting the electrode assembly body 1 adopt a split structure design. This not only allows the expansion electrode 11 and the docking electrode 12 to have different structural forms to increase the volume of the electrode assembly body 1, but also facilitates the subsequent assembly of the battery electrode assembly with the battery casing using a split assembly method. However, since the expansion electrode 11 and the docking electrode 12 of the electrode assembly body 1 adopt a split structure design, it is necessary to coat the contact surfaces of the two to achieve current conduction between them. The conductive coating is a functional thin film prepared on the surface of substrates such as metal, plastic, glass, and ceramic through a specific process. The core is to achieve current conduction by means of electronic or ionic conduction mechanisms. In terms of type, it mainly includes metal-based coatings with the best conductivity but higher cost, carbon-based coatings with good chemical stability and lightweight, conductive polymer coatings with outstanding flexibility and transparency but weak conductivity, and composite coatings with customizable performance. In this embodiment, each end face with a conductive coating is provided with a positive electrode conductive coating 3 and a negative electrode conductive coating 4. For the two tabs 2 connected to the same docking electrode 12, one tab 2 is coated with a positive conductive coating 3, and the other tab 2 is coated with a negative conductive coating 4. In addition, in order to accelerate the flow rate of the medium inside the battery, such as electrolyte or gas, the electrode assembly body 1 is also provided with flow guide grooves 13, which are located on the capacity expansion electrode 11 and the protective protrusion 121, respectively.

[0047] Optionally, the expansion electrode 11 includes a first end 111 and a second end 112 along the second direction. The end face of the expansion electrode 11 connected to the docking electrode 12 is provided with a mounting boss 113 extending from the first end 111 to the second end 112. The mounting boss 113 is provided with a docking groove 114. The end face of the docking electrode 12 facing the expansion electrode 11 is provided with a docking boss 122. The docking boss 122 is inserted into the docking groove 114. The projection range of the docking electrode 12 on the expansion electrode 11 along the first direction does not exceed the mounting boss 113.

[0048] By separately providing a mounting boss 113 on the expansion electrode 11 for connection with the docking electrode 12, the original size of the expansion electrode 11 is not reduced after the docking groove 114 is opened. Since the mounting boss 113 extends from the first end 111 to the second end 112 of the expansion electrode 11, the mounting boss 113 does not completely cover the end face of the expansion electrode 11 facing the docking electrode 12. Therefore, by ensuring that the projection range of the docking electrode 12 on the expansion electrode 11 along the first direction does not exceed the mounting boss 113, the suspended part between the docking electrode 12 and the expansion electrode 11 is avoided, and sufficient contact area is ensured between the docking electrode 12 and the expansion electrode 11.

[0049] In this embodiment, the height of the mounting boss 113 is consistent with the depth of the mating groove 114, thereby ensuring that the mating groove 114 has sufficient depth for insertion with the mating boss 122 without reducing the original volume of the expansion electrode 11.

[0050] Optionally, the distance between the end face of the protective boss 121 away from the expansion electrode 11 and the end face of the docking electrode 12 with the docking boss 122 along the first direction is E1, and the length of the first end 111 along the first direction is E2, and satisfies 1≤E2 / E1≤1.5.

[0051] Since the mounting boss 113 extends from the first end 111 of the expansion electrode 11 to the second end 112, but does not extend to the second end 112, the length of the first end 111 along the first direction is greater than the length of the second end 112 along the second direction. Therefore, by limiting the ratio between the length dimension E2 of the first end 111 along the first direction and the distance dimension E1 along the first direction between the end face of the protective boss 121 away from the expansion electrode 11 and the end face of the docking electrode 12 with the docking boss 122, the ratio is made to satisfy 1≤E2 / E1≤1.5. This avoids the ratio being too small, which would result in the length dimension E2 of the first end 111 of the expansion electrode 11 being too small, leading to insufficient volume of the expansion electrode 11 and failure to meet the expansion requirements of the battery electrode group. On the other hand, it avoids the ratio being too large, which would result in an excessive length difference between the first end 111 and the second end 112 of the expansion electrode 11, causing excessive shift of the center of gravity of the expansion electrode 11 and affecting the overall stability after battery assembly.

[0052] The ratio between the length dimension E2 of the first end 111 along the first direction and the distance dimension E1 between the end face of the protective boss 121 away from the expansion electrode 11 and the end face of the docking electrode 12 with the docking boss 122 along the first direction can be any value between 1 and 1.5 or any range between two values, such as 1, 1.1, 1.2, 1.3, 1.4, 1.5, etc.

[0053] Optionally, the width dimension of the docking electrode 12 along the third direction is B1, and the width dimension of the expansion electrode 11 along the third direction is B2, and the conditions are met: 16mm≤B2-B1≤60mm. By limiting the difference between the width dimension B2 of the expansion electrode 11 along the third direction and the width dimension B1 of the docking electrode 12 along the third direction, ensuring that it satisfies 16mm≤B2-B1≤60mm, the following measures are taken: Firstly, the difference is avoided from being too small, which would result in the expansion electrode 11 being too small while maintaining a certain width of the docking electrode 12, causing the volume of the expansion electrode 11 to not meet the expansion requirements of the battery electrode assembly. Secondly, the difference is avoided from being too large, which would result in the width of the docking electrode 12 being insufficient while meeting the expansion requirements, causing the area of ​​the docking electrode 12 for setting the protective boss 121 and the docking boss 122 to be too small, compressing the width dimensions of the protective boss 121 and the docking boss 122, resulting in poor structural strength of the protective boss 121 and the docking boss 122, making them prone to breakage.

[0054] The difference between the width dimension B2 of the expansion electrode 11 along the third direction and the width dimension B1 of the docking electrode 12 along the third direction can be any value between 16mm and 60mm or any range between two values, such as 16mm, 24.8mm, 33.6mm, 42.4mm, 51.2mm, 60mm, etc.

[0055] Optionally, the height dimension of the docking electrode 12 along the second direction is A1, and the height dimension of the expansion electrode 11 along the second direction is A2, satisfying 20mm≤A2-A1≤80mm. By limiting the difference between the height dimension A2 of the expansion electrode 11 along the second direction and the height dimension A1 of the docking electrode 12 along the second direction, ensuring that it satisfies 20mm≤A2-A1≤80mm, this avoids two problems: firstly, the difference is too small, resulting in the expansion electrode 11 being too small while maintaining a certain height of the docking electrode 12, thus failing to meet the expansion requirements of the battery electrode group; secondly, the difference is too large, resulting in the docking electrode 12 being too short while meeting the expansion requirements, leading to insufficient height of the docking electrode 12, making the area for setting the protective boss 121 and docking boss 122 too small, compressing the height dimension of the protective boss 121 and docking boss 122, resulting in poor structural strength of the protective boss 121 and docking boss 122, making them prone to breakage.

[0056] The difference between the height dimension A2 of the expansion electrode 11 along the second direction and the height dimension A1 of the docking electrode 12 along the second direction can be any value between 20mm and 80mm or any two values, such as 20mm, 30mm, 40mm, 50mm, 60mm, 70mm, 80mm, etc.

[0057] In this embodiment, to verify the impact of the above parameter limitations on the battery electrode assembly provided in this embodiment, as shown in Table 1, six sets of embodiments and six sets of comparative examples are provided for verification.

[0058] Table 1

[0059]

[0060] A comparison of Examples 1 to 6 with Comparative Examples 1 to 2 reveals that when the ratio between the length E2 of the first end 111 along the first direction and the distance E1 between the end face of the protective boss 121 away from the expansion electrode 11 and the end face of the docking electrode 12 with the docking boss 122 along the first direction is less than the minimum value in the range 1 ≤ E2 / E1 ≤ 1.5, the ratio is too small. This results in the length E2 of the first end 111 of the expansion electrode 11 along the first direction being too small, leading to insufficient volume of the expansion electrode 11. To meet the capacity expansion requirements of the battery electrode assembly, when the ratio between the length dimension E2 of the first end 111 along the first direction and the distance dimension E1 between the end face of the protective boss 121 away from the expansion electrode 11 and the end face of the docking electrode 12 with the docking boss 122 along the first direction is greater than the maximum value of the range 1≤E2 / E1≤1.5, the ratio is too large, resulting in an excessive length difference between the first end 111 and the second end 112 of the expansion electrode 11, causing the center of gravity of the expansion electrode 11 to shift too much, affecting the overall stability after battery assembly.

[0061] A comparison of Examples 1 to 6 with Comparative Examples 3 to 4 reveals that when the difference between the width dimension B2 of the expanded electrode 11 along the third direction and the width dimension B1 of the docking electrode 12 along the third direction is less than the minimum value within the range of 16mm ≤ B2 - B1 ≤ 60mm, the difference is too small. This results in the expanded electrode 11 being too small, even with the docking electrode 12 maintaining a constant width. Consequently, the volume of the expanded electrode 11 does not meet the capacity expansion requirements of the battery pack. When the difference between the width dimensions B1 of the mating electrode 12 along the third direction is greater than the maximum value of the range 16mm≤B2-B1≤60mm, the difference is too large. This results in insufficient width of the mating electrode 12, even if the volume of the expansion electrode 11 meets the expansion requirements. Consequently, the area of ​​the mating electrode 12 used to set the protective boss 121 and the mating boss 122 is too small, compressing the width dimensions of the protective boss 121 and the mating boss 122. This leads to poor structural strength of the protective boss 121 and the mating boss 122, making them prone to breakage.

[0062] A comparison of Examples 1 to 6 with Comparative Examples 5 to 6 reveals that when the difference between the height dimension A2 of the expanded electrode 11 along the second direction and the height dimension A1 of the docking electrode 12 along the second direction is less than the minimum value within the range of 20mm ≤ A2 - A1 ≤ 80mm, the difference is too small. This results in the expanded electrode 11 being too small while maintaining a constant height of the docking electrode 12, causing the volume of the expanded electrode 11 to fail to meet the capacity expansion requirements of the battery pack. When the difference between the height dimensions A1 of the docking electrode 12 along the second direction is greater than the maximum value of the range 20mm≤A2-A1≤80mm, the difference is too large. This results in insufficient height of the docking electrode 12, even if the volume of the expansion electrode 11 meets the expansion requirements. Consequently, the area of ​​the docking electrode 12 used to set the protective boss 121 and the docking boss 122 is too small, compressing the height dimensions of the protective boss 121 and the docking boss 122. This leads to poor structural strength of the protective boss 121 and the docking boss 122, making them prone to breakage.

[0063] Optionally, the height dimension of the protective protrusion 121 along the second direction is W1, and the ratio between the height dimension W1 of the protective protrusion 121 along the second direction and the height dimension A1 of the docking electrode 12 along the second direction satisfies 0.33≤W1 / A1≤0.6. By limiting the ratio between the height dimension W1 of the protective protrusion 121 along the second direction and the height dimension A1 of the docking electrode 12 along the second direction to satisfy 0.33≤W1 / A1≤0.6, it avoids both situations where the ratio is too small, resulting in a small height dimension of the protective protrusion 121, poor structural strength, and easy breakage, and where the ratio is too large, resulting in a large height dimension of the protective protrusion 121, compressing the height dimension of the remaining part of the docking electrode 12, reducing the overall volume of the docking electrode 12, and decreasing the overall capacity of the battery electrode assembly.

[0064] The ratio between the height dimension W1 of the protective boss 121 along the second direction and the height dimension A1 of the docking electrode 12 along the second direction can be any value between 0.33 and 0.6 or any range between two values, such as 0.33, 0.42, 0.51, 0.6, etc.

[0065] Optionally, the tab body 2 includes a tab base 21 and multiple connecting tabs 22. The multiple connecting tabs 22 are connected to the side of the tab base 21 facing away from the conductive coating. The tab base 21 has a plugging boss 23 on the side facing the protective boss 121. The end face of the protective boss 121 facing the tab body 2 has a plugging groove 123, and the plugging boss 23 is inserted into the plugging groove 123. By providing a plugging boss 23 on the tab base 21 and a plugging groove 123 on the protective boss 121, the connection between the tab body 2 and the docking electrode 12 is realized by plugging the plugging groove 123 and the plugging boss 23. Furthermore, by providing multiple connecting tabs 22 on the tab body 2, heat dissipation of the tab body 2 is facilitated, and conductivity is improved.

[0066] The length of the connecting tab 22 can be freely set according to requirements, and the lengths of multiple connecting tabs 22 disposed on the same tab base 21 can be the same or different. In this embodiment, each tab base 21 is provided with three equally spaced connecting tabs 22, and the length of the connecting tab 22 located in the middle is greater than the length of the connecting tabs 22 located on the two sides.

[0067] Furthermore, the distance between the two insertion grooves 123 along the second direction is W2. The difference between the height W1 of the protective boss 121 along the second direction and the distance W2 between the two insertion grooves 123 along the second direction satisfies 14mm ≤ W1 - W2 ≤ 40mm. By limiting the difference between the height W1 of the protective boss 121 along the second direction and the distance W2 between the two insertion grooves 123 along the second direction to satisfy 14mm ≤ W1 - W2 ≤ 40mm, we can avoid the following: on the one hand, if the difference is too small, the depth of the insertion groove 123 will be too shallow, resulting in insufficient contact area between the insertion groove 123 and the insertion boss 23, making it easy for the insertion boss 23 to detach from the insertion groove 123; on the other hand, we can avoid the difference being too large, resulting in the depth of the insertion groove 123 will be too deep, resulting in insufficient thickness in the area between the two insertion grooves 123 of the protective boss 121, poor structural strength, and easy breakage.

[0068] The difference between the height dimension W1 of the protective boss 121 along the second direction and the distance dimension W2 between the two insertion grooves 123 along the second direction can be any value between 14mm and 40mm or any two values, such as 14mm, 19.2mm, 24.4mm, 29.6mm, 34.8mm, 40mm, etc.

[0069] In this embodiment, to verify the impact of the above parameter limitations on the battery electrode assembly provided in this embodiment, as shown in Table 2, six sets of embodiments and four sets of comparative examples are provided for verification.

[0070] Table 2

[0071]

[0072] A comparison of Examples 7 to 12 with Comparative Examples 7 to 8 reveals that when the ratio between the height dimension W1 of the protective protrusion 121 along the second direction and the height dimension A1 of the docking electrode 12 along the second direction is less than the minimum value in the range 0.33≤W1 / A1≤0.6, the ratio is too small, resulting in a small height dimension of the protective protrusion 121, poor structural strength, and a tendency to break. Conversely, when the ratio between the height dimension W1 of the protective protrusion 121 along the second direction and the height dimension A1 of the docking electrode 12 along the second direction is greater than the maximum value in the range 0.33≤W1 / A1≤0.6, the ratio is too large, resulting in an excessively large height dimension of the protective protrusion 121. This compresses the height dimension of the remaining parts of the docking electrode 12, leading to a reduction in the overall volume of the docking electrode 12 and a decrease in the overall capacity of the battery pack.

[0073] A comparison of Examples 7 to 12 with Comparative Examples 9 to 10 reveals that when the difference between the height dimension W1 of the protective boss 121 along the second direction and the distance dimension W2 between the two insertion grooves 123 along the second direction is less than the minimum value of the range 14mm≤W1-W2≤40mm, the difference is too small, resulting in the insertion groove 123 being too shallow. This leads to insufficient contact area between the insertion groove 123 and the insertion boss 23, making it easy for the insertion boss 23 to detach from the insertion groove 123. Conversely, when the difference between the height dimension W1 of the protective boss 121 along the second direction and the distance dimension W2 between the two insertion grooves 123 along the second direction is greater than the maximum value of the range 14mm≤W1-W2≤40mm, the difference is too large, resulting in the insertion groove 123 being too deep. This leads to insufficient thickness in the area between the two insertion grooves 123 of the protective boss 121, resulting in poor structural strength and a tendency to break.

[0074] Optionally, the insertion groove 123 includes an abutting arc surface 1231, two first limiting inclined surfaces 1232 and two second limiting inclined surfaces 1233. The two first limiting inclined surfaces 1232 are connected to both sides of the abutting arc surface 1231 along a third direction and are inclined in a direction that approaches each other. The two second limiting inclined surfaces 1233 are connected to one end of the first limiting inclined surface 1232 away from the abutting arc surface 1231 and are inclined in a direction that moves away from each other, so as to form a limiting boss 1234 in the insertion groove 123. By providing an abutting arc surface 1231 within the insertion groove 123, the surfaces of the insertion groove 123 and the insertion boss 23 become smoother, facilitating their docking. Furthermore, by providing two mutually close first limiting inclined surfaces 1232 and two mutually distant second limiting inclined surfaces 1233, a limiting boss 1234 is formed within the insertion groove 123, thereby preventing the insertion boss 23 from dislodging from the insertion groove 123.

[0075] In this embodiment, a battery is also provided, which includes a battery cover, a battery housing, and the aforementioned battery electrode assembly. The battery housing is a hollow housing structure with at least one opening. The battery cover is disposed at the opening of the battery housing and closes the battery housing to form a closed cavity for accommodating the battery electrode assembly.

[0076] By applying the aforementioned battery electrode assembly, this battery not only reduces the risk of safety issues caused by overheating, but also increases the battery capacity, meeting the demand for improved battery energy density, thereby achieving longer battery life or longer power supply time.

[0077] Example 2

[0078] Figure 9 Embodiment 2 is shown, wherein components that are the same as or corresponding to those in Embodiment 1 are referred to using the same reference numerals as those in Embodiment 1. For simplicity, only the differences between Embodiment 2 and Embodiment 1 are described.

[0079] The difference lies in the fact that the structure of the docking electrode 12 with the protective protrusion 121 on one side and the structure of the electrode tab 2 in Embodiment 2 are different from the structure of the docking electrode 12 and the structure of the electrode tab 2 in Embodiment 1.

[0080] In this embodiment, the mating electrode 12 has a mounting groove 124 on the end face of the protective boss 121. The mounting groove 124 is located on both sides of the protective boss 121 along the third direction and has a connecting plane 1241, a connecting inclined surface 1242 and an abutting plane 1243. The connecting plane 1241 has inclined connecting inclined surfaces 1242 on both sides along the second direction and is connected to the lower end of the connecting inclined surface 1242. The abutting plane 1243 is parallel to the connecting plane 1241 and is connected to the higher end of the connecting inclined surface 1242. The electrode body 2 includes a first electrode body 24 and a second electrode body 25. The first electrode body 24 is disposed on the connecting plane 1241, and the second electrode body 25 is connected to both sides of the first electrode body 24 and disposed on the corresponding connecting inclined surface 1242.

[0081] By providing an installation groove 124 for connecting the tab 2 on the docking electrode 12, the distance between the protective boss 121 and the tab 2 is increased, thereby providing better protection for the tab 2 when the battery electrode assembly is installed in the casing. Furthermore, the first tab 24 is provided on the mounting plane, and the second tab 25 is provided on the connecting inclined surface 1242. This not only allows the tab 2 to be connected at various angles, but also increases the overall area of ​​the tab 2 and improves the current carrying capacity. The abutment surface 1243 is used to abut against the battery cover plate, increasing the stability after docking.

[0082] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A battery electrode assembly, characterized in that, The battery electrode assembly includes: The electrode assembly body includes an expansion electrode and a docking electrode. The cross-sectional area of ​​the docking electrode perpendicular to the first direction is smaller than the cross-sectional area of ​​the expansion electrode perpendicular to the first direction. The docking electrode is connected to both sides of the expansion electrode along the first direction, and a conductive coating is applied between the end faces of the docking electrode and the expansion electrode that are in contact. The docking electrode has a protective protrusion extending in a direction away from the expansion electrode on the side away from the expansion electrode. The electrode body is connected to the end face of the docking electrode body where the protective boss is provided, and the conductive coating is coated between the end faces of the electrode body and the docking electrode body that are in contact. The electrode body is located on both sides of the protective boss, and the height of the electrode body along the first direction is less than the height of the protective boss protrusion.

2. The battery electrode assembly according to claim 1, characterized in that, The expansion electrode includes a first end and a second end along the second direction. The end face of the expansion electrode connected to the docking electrode is provided with a mounting boss extending from the first end to the second end. A docking groove is provided on the mounting boss. The end face of the docking electrode facing the expansion electrode is provided with a docking boss. The docking boss is inserted into the docking groove. The projection range of the docking electrode on the expansion electrode along the first direction does not exceed the mounting boss.

3. The battery electrode assembly according to claim 2, characterized in that, The distance between the end face of the protective protrusion away from the expansion electrode and the end face of the docking electrode where the docking protrusion is located along the first direction is E1, and the length of the first end along the first direction is E2, and 1≤E2 / E1≤1.5 is satisfied.

4. The battery electrode assembly according to claim 1, characterized in that, The width dimension of the docking electrode along the third direction is B1, and the width dimension of the expansion electrode along the third direction is B2, and both satisfy 16mm≤B2-B1≤60mm.

5. The battery electrode assembly according to claim 1, characterized in that, The height dimension of the docking electrode along the second direction is A1, and the height dimension of the expansion electrode along the second direction is A2, and both satisfy 20mm≤A2-A1≤80mm.

6. The battery electrode assembly according to claim 5, characterized in that, The height dimension of the protective boss along the second direction is W1, and the ratio between the height dimension W1 of the protective boss along the second direction and the height dimension A1 of the docking electrode along the second direction satisfies 0.33≤W1 / A1≤0.

6.

7. The battery electrode assembly according to claim 6, characterized in that, The electrode body includes an electrode base and multiple connecting electrodes. The multiple connecting electrodes are connected to the side of the electrode base away from the conductive coating. The electrode base has a plugging boss on the side facing the protective boss. The protective boss has a plugging groove on the end face facing the electrode body. The plugging boss is inserted into the plugging groove. The distance between the two insertion grooves along the second direction is W2, and the difference between the height W1 of the protective boss along the second direction and the distance W2 between the two insertion grooves along the second direction satisfies 14mm≤W1-W2≤40mm.

8. The battery electrode assembly according to claim 7, characterized in that, The insertion groove includes an abutting arc surface, two first limiting inclined surfaces and two second limiting inclined surfaces. The two first limiting inclined surfaces are connected to both sides of the abutting arc surface along a third direction and are inclined in a direction that approaches each other. The two second limiting inclined surfaces are connected to one end of the first limiting inclined surface away from the abutting arc surface and are inclined in a direction that moves away from each other, so as to form a limiting protrusion in the insertion groove.

9. The battery electrode assembly according to claim 1, characterized in that, The docking electrode has a mounting groove on the end face of the protective boss. The mounting groove is located on both sides of the protective boss along a third direction and has a connecting plane, a connecting slope, and an abutting plane. The connecting plane has inclined connecting slopes on both sides along a second direction and is connected to the lower end of the connecting slope. The abutting plane is parallel to the connecting plane and is connected to the higher end of the connecting slope. The electrode body includes a first electrode body and a second electrode body. The first electrode body is disposed on the connecting plane, and the second electrode body is connected to both sides of the first electrode body and disposed on the corresponding connecting slope.

10. A battery, characterized in that, The battery includes a battery cover, a battery housing, and a battery electrode assembly as described in any one of claims 1-9. The battery housing is a hollow housing structure with an opening. The battery cover is disposed at the opening of the battery housing to close the battery housing and form a closed cavity for accommodating the battery electrode assembly.

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