Battery cell and battery pack
By dislocating the first and second pole cores in the battery cell, the problem of reserved distance between the liquid injection hole and the explosion-proof valve and the pole core is solved, and more efficient space utilization and energy density improvement are achieved.
Patent Information
- Application Number
- CN202510167764.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-14
- Publication Date
- 2025-05-13
AI Technical Summary
In the existing battery design, the reserved distance between the liquid injection hole and the explosion-proof valve and the pole core limits the size of the pole core, which in turn affects the energy density of the battery.
By providing the first and second pole cores in the case of the battery cell and dislocating them, the distance between the side surface where the ear of the first pole core is located and the first cover body is greater than the distance between the side surface where the ear of the second pole core is located and the first cover body. At the same time, the distance between the side surface of the first pole core and the second cover body is smaller than the distance between the side surface of the second pole core and the second cover body with respect to the side surface of the second pole core and the second cover body.
This misalignment setting not only provides the necessary reserved space for the injection hole and explosion-proof parts, improves the space utilization of the accommodating chamber, and thus increases the energy density of the battery.
Smart Images
Figure CN119994321A_ABST
Abstract
Description
Technical Field
[0001] The present application belongs to the field of battery technology, and in particular relates to a battery cell and a battery pack. Background Art
[0002] At present, the battery's injection hole usually needs to reserve a certain distance from the internal pole core to ensure smooth injection. At the same time, the battery's explosion-proof valve also needs to reserve a certain distance from the internal pole core to ensure smooth pressure relief and exhaust. The above reserved distances will limit the pole core size, thereby affecting the battery's energy density. Summary of the invention
[0003] An embodiment of the present application provides a battery cell, aiming to overcome the above-mentioned technical problems; another object of an embodiment of the present application is to provide a battery pack.
[0004] A battery cell according to an embodiment of the present application includes:
[0005] A shell having a containing cavity, wherein the shell is provided with a first opening at one end in its length direction and a second opening at the other end, wherein the first opening and the second opening are both connected to the containing cavity;
[0006] A cover assembly, comprising a first cover and a second cover, wherein the first cover is disposed on the first opening and has a liquid injection hole, and the second cover is disposed on the second opening and has an explosion-proof component;
[0007] A pole core assembly, comprising a first pole core and a second pole core, wherein the pole lug of the first pole core and the pole lug of the second pole core are located on the same side; wherein the distance between the first side surface where the pole lug of the first pole core is located and the first cover is greater than the distance between the second side surface where the pole lug of the second pole core is located and the first cover, and the distance between the third side surface of the first pole core opposite to the first side surface and the second cover is less than the distance between the fourth side surface of the second pole core opposite to the second side surface and the second cover;
[0008] Wherein, the injection hole is arranged opposite to the first pole core, and the explosion-proof component is arranged opposite to the second pole core.
[0009] In some embodiments, in the length direction, the orthographic projection of the injection hole on the first side surface does not overlap with the pole ear of the first pole core.
[0010] In some embodiments, the battery cell further includes a first insulating member disposed on a side of the first cover body facing the pole core assembly, and in the length direction, the first insulating member supports the first side surface and the second side surface respectively.
[0011] In some embodiments, the battery cell further includes a second insulating member disposed on a side of the second cover body facing the pole core assembly, and in the length direction, the second insulating member supports the third side surface and the fourth side surface respectively.
[0012] In some embodiments, the second insulating member is provided with an exhaust hole, the exhaust hole penetrates the second insulating member along the length direction, and at least a portion of the exhaust hole faces the explosion-proof member.
[0013] In some embodiments, the first pole core comprises a first body, a first pole tab and a second pole tab, the first body has the first side surface and the third side surface, the first pole tab and the second pole tab are both electrically connected to the first body, the second pole core comprises a second body, a third pole tab and a fourth pole tab, the second body has the second side surface and the fourth side surface, the third pole tab and the fourth pole tab are both electrically connected to the second body;
[0014] The cover assembly further includes a first pole and a second pole, wherein the first pole and the second pole are both arranged on the first cover, the first pole tab and the third pole tab are respectively electrically connected to the first pole, and the second pole tab and the fourth pole tab are respectively electrically connected to the second pole.
[0015] In some embodiments, the first body and the second body are arranged along the thickness direction of the shell, the first cover body has a width e in the thickness direction, and the distance between the edge of the injection hole and the side of the first cover body in the thickness direction is f, wherein: f≥e / 5 is satisfied.
[0016] In some embodiments, the first body and the second body are arranged along the thickness direction of the shell, the second cover has a width j in the thickness direction, and the distance between the explosion-proof component and the side of the second cover in the thickness direction is k, wherein: k≥j / 5 is satisfied.
[0017] In some embodiments, the difference between the distance between the first side and the first cover body and the distance between the second side and the first cover body is in the range of [1,3] mm;
[0018] And / or, the difference between the distance between the third side surface and the second cover body and the distance between the fourth side surface and the second cover body is in the range of [1,3] mm.
[0019] Accordingly, an embodiment of the present application provides a battery pack, which includes the above-mentioned battery cell.
[0020] Beneficial effects: A battery cell provided in an embodiment of the present application includes a shell, a cover assembly and a pole core assembly. The shell has a accommodating cavity, and the shell is provided with a first opening at one end in its length direction and a second opening at the other end, and the first opening and the second opening are both connected to the accommodating cavity. The cover assembly includes a first cover and a second cover, the first cover is provided with a liquid injection hole, the second cover is provided with a second opening, and the second cover is provided with an explosion-proof component. The pole core assembly includes a first pole core and a second pole core, and the pole lug of the first pole core and the pole lug of the second pole core are located on the same side. The distance between the first side surface where the pole lug of the first pole core is located and the first cover is greater than the distance between the second side surface where the pole lug of the second pole core is located and the first cover, and the distance between the third side surface of the first pole core relative to the first side surface and the second cover is less than the distance between the fourth side surface of the second pole core relative to the second side surface and the second cover. The liquid injection hole is arranged opposite to the first pole core, and the explosion-proof component is arranged opposite to the second pole core. By staggering the first pole core and the second pole core in the accommodating cavity, on the one hand, necessary reserved space is provided for the injection hole and the explosion-proof component, and on the other hand, the space utilization rate of the accommodating cavity is improved, which is beneficial to improving the energy density of the battery. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.
[0022] Figure 1 A schematic diagram of the explosion structure of a battery cell provided in an embodiment of the present application;
[0023] Figure 2 A schematic diagram of the cross-sectional structure of the interior of a battery cell provided in an embodiment of the present application;
[0024] Figure numerals: 1, shell; 10, accommodating cavity; 11, first opening; 12, second opening; 2, cover assembly; 20, first cover; 200, injection hole; 21, second cover; 22, first pole; 23, second pole; 3, pole core assembly; 30, first pole; 300, first body; 3000, first side; 3001, third side; 301, first pole ear; 302, second pole ear; 31, second pole core; 310, second body; 3100, second side; 3101, fourth side; 311, third pole ear; 312, fourth pole ear; 4, explosion-proof component; 5, first insulating component; 6, second insulating component; 60, exhaust hole; X, length direction; Y, thickness direction; Z, width direction. DETAILED DESCRIPTION
[0025] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.
[0026] In the description of the present application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, "plurality" means two or more, and at least one means one, two or more, unless otherwise clearly and specifically defined.
[0027] The battery's injection hole usually needs to reserve a certain distance from the internal pole core to ensure smooth injection. At the same time, the battery's explosion-proof valve also needs to reserve a certain distance from the internal pole core to ensure smooth pressure relief and exhaust. At present, in order to increase the battery capacity, multiple pole cores are usually set in the battery, and the multiple pole cores are usually assembled into the battery casing by aligning the cores with each other. The above-mentioned reserved distances will limit the size of each pole core, thereby affecting the energy density of the battery.
[0028] In view of this, refer to Figure 1 and Figure 2 , an embodiment of the present application provides a battery cell to overcome at least one of the above-mentioned technical problems.
[0029] Reference Figure 1 and Figure 2 The battery cell includes a shell 1, a cover assembly 2 and a pole core assembly 3.
[0030] It should be noted that the following embodiments introduce intersecting length directions X, thickness directions Y, and width directions Z. Among them, the length direction X is roughly parallel to the overall length direction of the battery cell in the embodiment of the present application, the thickness direction Y is roughly parallel to the overall thickness direction of the battery cell in the embodiment of the present application, and the width direction Z is roughly parallel to the overall width direction of the battery in the embodiment of the present application.
[0031] The housing 1 has a housing cavity 10, and the housing 1 is provided with a first opening 11 at one end in the length direction X, and a second opening 12 at the other end, and the first opening 11 and the second opening 12 are both connected to the housing cavity 10. The cover assembly 2 includes a first cover 20 and a second cover 21, the first cover 20 is covered on the first opening 11, the first cover 20 is provided with a liquid injection hole 200, the second cover 21 is covered on the second opening 12, and the second cover 21 is provided with an explosion-proof component 4. The pole core assembly 3 includes a first pole core 30 and a second pole core 31 arranged along the thickness direction Y, and the pole lug of the first pole core 30 and the pole lug of the second pole core 31 are located on the same side. The distance a between the first side surface 3000 where the pole ear of the first pole core 30 is located and the first cover body 20 is greater than the distance b between the second side surface 3100 where the pole ear of the second pole core 31 is located and the first cover body 20, and the distance c between the third side surface 3001 of the first pole core 30 relative to the first side surface 3000 and the second cover body 21 is less than the distance d between the fourth side surface 3101 of the second pole core 31 relative to the second side surface 3100 and the second cover body 21.
[0032] The injection hole 200 is arranged opposite to the first pole core 30, and the explosion-proof component 4 is arranged opposite to the second pole core 31. By staggering the first pole core 30 and the second pole core 31 in the accommodating chamber 10, on the one hand, it is ensured that the necessary reserved space is provided for the injection hole 200 and the explosion-proof component 4, and on the other hand, the space utilization rate of the accommodating chamber 10 is improved, which is conducive to improving the energy density of the battery.
[0033] In some embodiments, reference Figure 1 and Figure 2 The first pole core 30 includes a first body 300, a first pole tab 301 and a second pole tab 302. The first pole tab 301 and the second pole tab 302 are both provided on the first side 3000 and arranged along the width direction Z, and the first pole tab 301 and the second pole tab 302 are both electrically connected to the first body 300. The second pole core 31 includes a second body 310, a third pole tab 311 and a fourth pole tab 312. The third pole tab 311 and the fourth pole tab 312 are both provided on the second side 3100 and arranged along the width direction Z, and the third pole tab 311 and the fourth pole tab 312 are both electrically connected to the second body 310. The cover assembly 2 also includes a first pole column 22 and a second pole column 23. The first pole column 22 and the second pole column 23 are both provided on the first cover 20. The first pole tab 301 and the third pole tab 311 are respectively electrically connected to the first pole column 22, and the second pole tab 302 and the fourth pole tab 312 are respectively electrically connected to the second pole column 23.
[0034] In this embodiment, the first body 300 and the second body 310 are staggered in the length direction X in the accommodating chamber 10, and space is reserved between the first side 3000 and the injection hole 200, and between the fourth side 3101 and the explosion-proof component 4, so as to meet the exhaust space of the explosion-proof component 4 under safe working conditions and to smoothly inject liquid into the injection hole 200. At the same time, the distance between the third side 3001 and the second cover 21 and the distance between the second side 3100 and the first cover 20 are reduced, so as to achieve the effect of improving the space utilization rate of the accommodating chamber 10 and improving the energy density of the battery. The first pole ear 301, the second pole ear 302, the third pole ear 311 and the fourth pole ear 312 compensate for the staggered spacing of the first body 300 and the second body 310, so as to ensure the stability of the first pole ear 301 and the third pole ear 311 electrically connected to the first pole 22, and the second pole ear 302 and the fourth pole ear 312 electrically connected to the second pole 23.
[0035] In some embodiments, reference Figure 2 , the difference between the distance a between the first side surface 3000 and the first cover body 20 and the distance b between the second side surface 3100 and the first cover body 20 is in the range of [1,3] mm. The difference between a and b is controlled to be no less than 1 mm, so as to meet the requirement of reserving sufficient space between the first side surface 3000 and the injection hole 200. At the same time, the difference between a and b is controlled to be no more than 3 mm, so as to avoid excessively increasing the size of the first pole tab 301 and the second pole tab 302 in the length direction X to meet the compensation misalignment size, thereby increasing the internal resistance of the battery cell, reducing the power transmission efficiency, and affecting the overall performance of the battery cell.
[0036] In some embodiments, reference Figure 2 , the difference between the distance c between the third side 3001 and the second cover body 21 and the distance d between the fourth side 3101 and the second cover body 21 is in the range of [1,3] mm. The difference between c and d is controlled to be no less than 1 mm, which is conducive to reserving sufficient space between the fourth side 3101 and the explosion-proof part 4, ensuring that the explosion-proof part 4 can smoothly release pressure and exhaust air under safe working conditions. At the same time, the difference between c and d is controlled to be no more than 3 mm, which is conducive to avoiding the problem of too large a reserved space between the fourth side 3101 and the explosion-proof part 4, resulting in a reduced space utilization rate in the battery cell, affecting the compactness of the overall battery cell design.
[0037] In some embodiments, reference Figure 1 and Figure 2, in the length direction X, the orthographic projection of the injection hole 200 on the first side surface 3000 does not overlap with the pole ear of the first pole core 30. In this embodiment, the injection hole 200 is arranged between the first pole ear 301 and the second pole ear 302, so as to avoid the electrolyte from directly flushing the first pole ear 301 and the second pole ear 302 during the injection process, and reduce the risk of the electrolyte flushing the burrs of the first pole ear 301 and the second pole ear 302 and entering the first body 300 and the second body 310 to cause puncture short circuit and the like. It can be understood that in other embodiments, the injection hole 200 can also be arranged on the side of the first pole ear 301 away from the second pole ear 302 or the side of the second pole ear 302 away from the first pole ear 301, so as to meet the requirement that the electrolyte does not directly flush the first pole ear 301 and the second pole ear 302, which will not be repeated here.
[0038] In some embodiments, reference Figure 1 and Figure 2 The battery cell also includes a first insulating member 5, which is disposed on the side of the first cover 20 facing the pole core assembly 3. In the length direction X, the first insulating member 5 supports the first side surface 3000 and the second side surface 3100 respectively. The first insulating member 5 is insulated between the first body 300 and the first cover 20 and between the second body 310 and the first cover 20, thereby improving the safety of the battery cell. At the same time, the first insulating member 5 can fit the shell 1 when the first cover 20 covers the first opening 11, thereby improving the sealing effect and reducing the risk of electrolyte leakage. In addition, the first insulating member 5 can form a buffering support effect for the first pole core 30 and the second pole core 31, thereby improving the anti-seismic protection effect.
[0039] In some embodiments, reference Figure 1 and Figure 2 The battery cell also includes a second insulating member 6, which is disposed on the side of the second cover 21 facing the pole core assembly 3. In the length direction X, the second insulating member 6 supports the third side 3001 and the fourth side 3101 respectively. The second insulating member 6 is insulated between the first body 300 and the second cover 21 and the second body 310 and the second cover 21, thereby improving the safety of the battery cell. At the same time, the second insulating member 6 can fit the shell 1 when the second cover 21 is covered on the second opening 12, thereby improving the sealing effect and reducing the risk of electrolyte leakage. In addition, the first insulating member 5 can form a buffering support effect for the first pole core 30 and the second pole core 31, thereby improving the anti-seismic protection effect.
[0040] In some embodiments, reference Figure 1 The second insulating member 6 is provided with an exhaust hole 60, which penetrates the second insulating member 6 along the length direction X, and at least part of the exhaust hole 60 faces the explosion-proof member 4. The exhaust hole 60 avoids blocking the exhaust passage of the explosion-proof member 4 under safe working conditions, thereby improving the safety of the battery cell.
[0041] In some embodiments, the first cover 20 has a width e in the thickness direction Y, and the distance between the edge of the injection hole 200 and the side of the first cover 20 in the thickness direction Y is f, where f≥e / 5 is satisfied. Figure 1 As shown, the distance f is the distance between the injection hole 200 and the side of the first cover body 20 closer to it, which may specifically refer to the distance between the edge and the side of the injection hole 200. In other embodiments, it may also be the distance between the center and the side of the injection hole 200. This arrangement is conducive to preventing the electrolyte from impacting the side wall of the shell 1 during the injection process of the injection hole 200, reducing the risk of the electrolyte impact damaging the membrane material inside the shell 1. In addition, it avoids the problem of stress concentration on the edge of the first cover body 20 caused by the opening position being too close to the side of the first cover body 20, reducing the risk of deformation of the first shell 1.
[0042] In some embodiments, the first body 300 and the second body 310 are arranged along the thickness direction Y of the shell 1, the second cover 21 has a width j in the thickness direction Y, and the distance between the explosion-proof component 4 and the side of the second cover 21 in the thickness direction Y is k, where k≥j / 5 is satisfied. This is helpful to avoid the problem of stress concentration on the edge of the second cover 21 caused by the opening position of the second cover 21 corresponding to the explosion-proof component 4 being too close to the side of the second cover 21, thereby reducing the risk of deformation of the second shell 1.
[0043] Accordingly, an embodiment of the present application provides a battery pack, which includes the above-mentioned battery cell. It is understandable that the battery pack can have all the technical features and corresponding beneficial effects of the above-mentioned battery cell, which will not be described in detail here.
[0044] The above is a detailed introduction to a battery cell and a battery pack provided in the embodiments of the present application, and the principles and implementation methods of the present application are explained by applying specific examples. The description of the above embodiments is only used to help understand the technical solution and its core idea of the present application; ordinary technicians in this field should understand that: they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present application.
Claims
1. A battery cell, characterized in that: include: A shell (1) having a containing cavity (10); the shell (1) is provided with a first opening (11) at one end in its length direction (X), and a second opening (12) at the other end; the first opening (11) and the second opening (12) are both connected to the containing cavity (10); A cover assembly (2) comprises a first cover (20) and a second cover (21), wherein the first cover (20) is disposed on the first opening (11) and is provided with a liquid injection hole (200), and the second cover (21) is disposed on the second opening (12) and is provided with an explosion-proof component (4); A pole core assembly (3), comprising a first pole core (30) and a second pole core (31), wherein the pole ear of the first pole core (30) and the pole ear of the second pole core (31) are located on the same side; wherein the distance (a) between the first side surface (3000) where the pole ear of the first pole core (30) is located and the first cover (20) is greater than the distance (b) between the second side surface (3100) where the pole ear of the second pole core (31) is located and the first cover (20), and the distance (c) between the third side surface (3001) of the first pole core (30) opposite to the first side surface (3000) and the second cover (21) is less than the distance (d) between the fourth side surface (3101) of the second pole core (31) opposite to the second side surface (3100) and the second cover (21); The injection hole (200) is arranged opposite to the first pole core (30), and the explosion-proof component (4) is arranged opposite to the second pole core (31).
2. The battery cell according to claim 1, characterized in that: In the length direction (X), the orthographic projection of the liquid injection hole (200) on the first side surface (3000) does not overlap with the pole ear of the first pole core (30).
3. The battery cell according to claim 1, characterized in that: The battery cell further comprises: The first insulating member (5) is arranged on the side of the first cover (20) facing the pole core assembly (3), and in the length direction (X), the first insulating member (5) supports the first side surface (3000) and the second side surface (3100) respectively.
4. The battery cell according to claim 1, characterized in that: The battery cell further comprises: The second insulating member (6) is arranged on the side of the second cover (21) facing the pole core assembly (3), and in the length direction (X), the second insulating member (6) supports the third side surface (3001) and the fourth side surface (3101) respectively.
5. The battery cell according to claim 4, characterized in that: The second insulating component (6) is provided with an exhaust hole (60), the exhaust hole (60) passes through the second insulating component (6) along the length direction (X), and at least a portion of the exhaust hole (60) faces the explosion-proof component (4).
6. The battery cell according to any one of claims 1 to 5, characterized in that: The first pole core (30) comprises a first body (300), a first pole lug (301) and a second pole lug (302); the first body (300) has the first side surface (3000) and the third side surface (3001); the first pole lug (301) and the second pole lug (302) are both electrically connected to the first body (300); the second pole core (31) comprises a second body (310), a third pole lug (311) and a fourth pole lug (312); the second body (310) has the second side surface (3100) and the fourth side surface (3101); the third pole lug (311) and the fourth pole lug (312) are both electrically connected to the second body (310); The cover assembly (2) further comprises a first pole (22) and a second pole (23), wherein the first pole (22) and the second pole (23) are both arranged on the first cover (20), the first pole lug (301) and the third pole lug (311) are respectively electrically connected to the first pole (22), and the second pole lug (302) and the fourth pole lug (312) are respectively electrically connected to the second pole (23).
7. The battery cell according to claim 6, characterized in that: The first body (300) and the second body (310) are arranged along the thickness direction (Y) of the shell (1), the first cover body (20) has a width e in the thickness direction (Y), and the distance between the edge of the injection hole (200) and the side of the first cover body (20) in the thickness direction (Y) is f, wherein: f≥e / 5 is satisfied.
8. The battery cell according to claim 6, characterized in that: The first body (300) and the second body (310) are arranged along the thickness direction (Y) of the shell (1), the second cover (21) has a width j in the thickness direction (Y), and the distance between the sides of the explosion-proof component (4) and the second cover (21) in the thickness direction (Y) is k, wherein: k≥j / 5 is satisfied.
9. The battery cell according to claim 6, characterized in that: The difference between the distance (a) between the first side surface (3000) and the first cover body (20) and the distance (b) between the second side surface (3100) and the first cover body (20) is in the range of [1,3] mm; And / or, the difference between the distance (c) between the third side surface (3001) and the second cover body (21) and the distance (d) between the fourth side surface (3101) and the second cover body (21) is in the range of [1,3] mm.
10. A battery pack, characterized in that: The invention comprises the battery cell according to any one of claims 1 to 9.