Cylindrical battery, electronic device, and current collecting disc

Abstract

A cylindrical battery (100), an electronic device, and a current collecting disc (40). The cylindrical battery (100) comprises a case (10), a cover plate assembly (30), the current collecting disc (40), and an electrode assembly (20). The case (10) and the cover plate assembly (30) define an accommodating cavity (11). The electrode assembly (20) and the current collecting disc (40) are arranged in the accommodating cavity (11). The current collecting disc (40) is arranged between the electrode assembly (20) and the cover plate assembly (30). The current collecting disc (40) comprises a first part (41), a second part (42), and a third part (43). The first part (41), the second part (42), and the third part (43) are sequentially arranged in a first direction (Z). The second part (42) is connected between the first part (41) and the third part (43). The first part (41) is electrically connected to the electrode assembly (20). The third part (43) is connected to the cover plate assembly (30). The first part (41) is provided with a first through hole (411). The second part (42) is provided with a second through hole (421). The second through hole (421) at least partially overlaps the first through hole (411) in the first direction (Z). The impact of the current collecting disc (40) on gas in the cylindrical battery (100) can be reduced, reducing the risk of explosion of the cylindrical battery (100), and improving the electrolyte infiltration efficiency of the cylindrical battery (100).

Description

Cylindrical battery, electronic device and current collecting plate TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a cylindrical battery, an electronic device and a current collecting plate. BACKGROUND

[0002] The cylindrical battery has the advantages of high automation, low cost and good consistency. With the improvement of people's living standards, the requirement for the power of the cylindrical battery is also getting higher and higher, and it is required to provide greater power output for the cylindrical battery and to reduce the charge and discharge temperature rise of the cylindrical battery.

[0003] The traditional high-power cylindrical battery usually includes a current collecting plate, one side of the current collecting plate is electrically connected with a cover plate assembly of a shell, and the other side is electrically connected with an electrode assembly. After the cover plate assembly is closed, the current collecting plate forms a multi-layer folded structure.

[0004] In order to ensure the safety of the cylindrical battery under extreme conditions (such as short circuit), a power-off device or an explosion-proof sheet is usually provided. In extreme cases, the cylindrical battery produces gas rapidly inside, the internal pressure increases, and the corresponding power-off or pressure relief function is triggered to avoid more serious failure consequences. Since the electrode assembly of the cylindrical battery has a center hole, part of the gas needs to be transmitted to the power-off device or the explosion-proof sheet through the center hole, but the multi-folded current collecting plate is easy to cover the center hole, thereby hindering the flow of internal gas and the transmission of gas pressure, which is easy to cause the cylindrical battery to swell or even explode.

[0005] SUMMARY

[0006] The present application aims to provide a cylindrical battery, an electronic device and a current collecting plate, and aims to improve the technical problem that the current collecting plate hinders the flow of internal gas.

[0007] According to a first aspect of the present application, a cylindrical battery is provided, including a shell, a cover plate assembly, a current collecting plate and an electrode assembly, the shell and the cover plate assembly form an accommodating cavity, the electrode assembly and the current collecting plate are arranged in the accommodating cavity, and the current collecting plate is arranged between the electrode assembly and the cover plate assembly. The current collecting plate includes a first part, a second part and a third part, which are arranged in sequence along a first direction, the second part is connected between the first part and the third part, the first part is electrically connected with the electrode assembly, and the third part is connected with the cover plate assembly. The first part is provided with a first through hole, the second part is provided with a second through hole, and the second through hole at least partially overlaps with the first through hole along the first direction.

[0008] In the technical solution, the current collector plate with the three-layer folding structure can facilitate the electrical connection of the current collector plate with the electrode assembly and the cover plate assembly. The second through hole at least partially overlaps the first through hole, which forms a gas discharge channel with the first through hole and the second through hole. When the cylindrical battery is in an extreme working condition, such as short circuit or thermal runaway, gas is rapidly generated inside the battery. The gas can be discharged towards the cover plate assembly through the first through hole and the second through hole, so that the gas can impact the cover plate assembly near the cover plate assembly, which can facilitate the triggering of the power-off device or pressure relief valve of the cover plate assembly in the extreme working condition, so as to quickly power off or discharge the gas and reduce the explosion risk of the cylindrical battery.

[0009] Meanwhile, the first through hole and the second through hole can serve as an electrolyte transmission channel. In the electrolyte injection process of the cylindrical battery, the electrolyte injected through the electrolyte injection hole of the cover plate assembly can be directly transmitted to the electrode assembly through the first through hole and the second through hole, which can shorten the electrolyte transmission path, facilitate the full immersion of the electrode assembly in the electrolyte, and improve the electrolyte injection efficiency (or the electrolyte immersion efficiency).

[0010] In some preferred embodiments, the electrode assembly has a central hole. In the first direction, the second through hole, the first through hole, and the central hole at least partially overlap, so that the second through hole, the first through hole, and the central hole form a gas transmission channel. The internal gas can be directly discharged towards the cover plate assembly through the central hole, the first through hole, and the second through hole. The gas flow transmission channel is larger and can accommodate a larger gas flow, which is conducive to the quick triggering of the power-off device or pressure relief valve of the cover plate assembly in the extreme working condition. In the electrolyte injection process, the electrolyte can diffuse towards the electrode assembly at the central hole, and the external electrolyte can immerse the electrode assembly from the outside of the electrode assembly, which improves the immersion efficiency of the electrode assembly and the electrolyte injection efficiency.

[0011] In some preferred embodiments, in the first direction, the projection of the third portion overlaps the second through hole. The cylindrical battery further includes a rupture disc electrically connected to the cover plate assembly. The rupture disc has a connecting portion protruding towards the third portion and electrically connected to the third portion. The rupture disc and the third portion have a first space therebetween, and the second through hole communicates with the first space. The gas can impact the connecting portion of the rupture disc in the first space, which can facilitate the protrusion of the connecting portion in a direction away from the third portion, and further cause the electrical connection between the connecting portion and the third portion to fail, so as to quickly power off and reduce the explosion risk of the cylindrical battery.

[0012] In some preferred embodiments, the cylindrical battery further comprises a connecting plate electrically connected between the rupture disc and the third portion, the connecting plate is configured to improve the current carrying capacity. The connecting plate is provided with a weak portion connected with the connecting portion. The weak portion is configured to facilitate the connection between the connecting portion and the connecting plate. In normal working conditions, the weak portion is connected with the main body portion to transmit current, and in extreme working conditions, the connecting portion drives the weak portion to protrude away from the connecting plate, so that the weak portion is separated from the main body portion, and the electrical connection between the rupture disc and the connecting plate is disconnected.

[0013] In some preferred embodiments, along the first direction, the weak portion and the third portion at least partially overlap. By shielding the weak portion with the third portion, the direct impact of the gas in the second through hole and the first through hole on the weak portion can be reduced, and the power failure of the cylindrical battery in normal working conditions can be reduced.

[0014] In some preferred embodiments, the third portion is provided with a third through hole, and the first portion is further provided with a fourth through hole, along the first direction, the third through hole at least partially overlaps with the first through hole or the fourth through hole. More gas transmission channels can be provided, the gas transmission path is shortened, and the triggering of the above-mentioned rupture disc in extreme working conditions is more beneficial. Alternatively, during the liquid injection stage, the electrolyte can directly reach the first through hole or the fourth through hole through the third through hole, and then quickly reach the center hole, so as to quickly soak the electrode assembly and improve the liquid injection efficiency.

[0015] In some preferred embodiments, along the first direction, the projection of the third portion is within the projection of the second portion, and the third portion does not completely cover the first through hole, further shortening the gas transmission path, reducing the explosion risk of the cylindrical battery, and also shortening the liquid injection path and improving the liquid injection efficiency.

[0016] In some preferred embodiments, the surface of the first portion facing the second portion is provided with a first protruding portion, the first protruding portion can be supported between the third portion and the first portion, a gas discharge space is provided, and the gas flowing through the first through hole and the second through hole is more beneficial to be discharged towards the cover plate assembly.

[0017] Optionally, the surface of the third portion facing the second portion is provided with a second protruding portion, further providing a gas transmission space, and the gas is more beneficial to be quickly transmitted to the vicinity of the rupture disc, further reducing the explosion risk of the cylindrical battery.

[0018] In some preferred embodiments, the maximum size of the outer contour of the first through hole is D1, the maximum size of the outer contour of the second through hole is D2, and 50%≤D2 / D1≤95%. By adopting this configuration, the assembly tolerance problem can be reduced, and the influence of the current carrying problem caused by the second through hole on the second portion can be reduced. Preferably, 70%≤D2 / D1≤90%.

[0019] In some preferred embodiments, along the second direction, the first direction and the second direction are perpendicular to each other, the width of the second portion is W2, and 5%≤D2 / W2≤30%. This can reduce the influence of the second through hole on the current carrying capacity of the second portion while making the second portion have higher strength, thereby improving the power output of the cylindrical battery.

[0020] In some preferred embodiments, along the second direction, the maximum width of the first portion is W1, the maximum width of the second portion is W2, and the maximum width of the third portion is W3. 40%≤W2 / W1≤80% makes the current collector have higher strength, facilitates the folding between the first portion and the second portion, and reduces the breaking phenomenon during folding. 30%≤W3 / W1≤80% improves the current carrying capacity of the third portion and the second portion and reduces the breaking phenomenon between the second portion and the third portion. The first direction and the second direction are perpendicular to each other.

[0021] In some preferred embodiments, along the third direction, the maximum length of the first portion is L1, the maximum length of the second portion is L2, and the maximum length of the third portion is L3. 60%≤L2 / L1≤100% and 60%≤L3 / L2≤100% further improve the current carrying capacity of the current collector while making the current collector have higher strength, facilitating the folding of the first portion, the second portion, and the third portion, and reducing the risk of folding breaking. The first direction and the third direction are perpendicular to each other.

[0022] In a second aspect, the present application further provides an electronic device comprising the cylindrical battery according to any one of the embodiments of the first aspect.

[0023] In a third aspect, the present application further provides a current collector applied to the cylindrical battery according to any one of the embodiments of the first aspect. The current collector comprises a first portion, a second portion, and a third portion. The second portion is connected between the first portion and the third portion, and the connection between the first portion and the second portion has a first connection section. The first portion is provided with a first through hole, and the second portion is provided with a second through hole. The maximum size of the outer contour of the second through hole is D2. Along the length direction of the current collector, the projection of the first through hole and the projection of the second through hole at least partially overlap. The distance from the first connection section to the first through hole is M, and the distance from the first connection section to the second through hole is N. N≤M<N+D2.

[0024] Additional aspects and advantages of the embodiments of the present application will be in part apparent and in part explicit herein below in the description. BRIEF DESCRIPTION OF DRAWINGS

[0025] One or more embodiments are illustrated by way of example in the figures that are not intended to be limiting of the present embodiments. Like numbers refer to like elements throughout. Dimensions of certain elements can be exaggerated for clarity.

[0026] FIG. 1 is a schematic diagram of a cylindrical battery according to some embodiments of the present application;

[0027] FIG. 2 is an exploded schematic diagram of a cylindrical battery according to some embodiments of the present application (excluding the electrode assembly);

[0028] FIG. 3 is a schematic diagram of a winding structure of an electrode assembly according to some embodiments of the present application;

[0029] FIG. 4 is an enlarged view of a portion of FIG. 1;

[0030] FIG. 5 is a schematic diagram of a folding structure of a current collector according to some embodiments of the present application;

[0031] FIG. 6 is a schematic diagram of an unfolding structure of a current collector according to some embodiments of the present application;

[0032] FIG. 7 is a schematic diagram of a folding structure of a current collector according to some embodiments of the present application;

[0033] FIG. 8 is a schematic diagram of a connection structure of a current collector and a rupture disc according to some embodiments of the present application;

[0034] FIG. 9 is an exploded schematic diagram of a connection structure of a current collector and a rupture disc according to some embodiments of the present application;

[0035] FIG. 10 is a schematic diagram of an unfolding structure of a current collector according to some embodiments of the present application;

[0036] FIG. 11 is a schematic diagram of a folding structure of a current collector according to some embodiments of the present application;

[0037] FIG. 12 is a schematic diagram of an unfolding structure of a current collector according to some embodiments of the present application;

[0038] FIG. 13 is a schematic diagram of an unfolding structure of a current collector according to some embodiments of the present application.

[0039] Explanation of reference signs: 100, cylindrical battery; 10, housing; 11, accommodating cavity; 12, open end; 13, second end portion; 20, electrode assembly; 21, positive electrode sheet; 22, negative electrode sheet; 23, separator; 24, central hole; 30, cover plate assembly; 31, pole post; 32, plate body; 40, current collector plate; 41, first portion; 411, first through hole; 4111, extension portion; 412, fourth through hole; 413, first protruding portion; 42, second portion; 421, second through hole; 43, third portion; 431, third through hole; 432, second protruding portion; 44, first connecting section; 50, explosion-proof sheet; 51, connecting portion; 52, fixing portion; 60, first space; 70, insulating member; 80, connecting plate; 81, weak portion; 82, main body portion; Z, first direction; X, second direction; Y, third direction. DETAILED DESCRIPTION

[0040] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application.

[0041] In the present application, the phrase “embodiment” means that the specific features, structures or characteristics described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase at various places in the specification does not necessarily mean that it refers to the same embodiment, nor is it an independent or alternative embodiment that is not mutually exclusive with other embodiments.

[0042] In the description of the embodiments of the present application, the technical terms “first”, “second” and the like are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of “a plurality of” is two or more, unless otherwise explicitly specified.

[0043] In the description of the embodiments of the present application, the term “and / or” is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A existing alone, A and B existing together, and B existing alone. In addition, the character “ / ” herein generally represents an “or” relationship between the front and rear associated objects.

[0044] The technical features involved in the different embodiments of the present application described below can be combined with each other as long as there is no conflict between them.

[0045] In a first aspect, the application provides a cylindrical battery 100, as shown in FIGS. 1 and 2. The cylindrical battery 100 includes a housing 10, an electrode assembly 20, a cover plate assembly 30, and a current collector 40. The housing 10 and the cover plate assembly 30 form a receiving cavity 11. The electrode assembly 20 and the current collector 40 are disposed in the receiving cavity 11. The current collector 40 is disposed between the electrode assembly 20 and the cover plate assembly 30.

[0046] The housing 10 is used to accommodate the electrode assembly 20 and an electrolyte (not shown in the drawings). The electrolyte is used to soak the electrode assembly 20 in the housing 10 to generate an electrochemical reaction. The housing 10 can have a cylindrical shape. Along the axial direction (the first direction Z) of the housing 10, the housing 10 includes a first end portion (not shown in the drawings) and a second end portion 13. In some embodiments, the first end portion is provided with an opening 12. The electrode assembly 20 can be placed in the housing 10 through the opening 12 of the first end portion. The opening 12 of the first end portion is sealed by the cover plate assembly 30. The second end portion 13 can be directly sealed to form a sealed receiving cavity 11. In other embodiments, the second end portion 13 can also be provided with an opening. Another cover plate assembly is used to connect the second end portion 13 to the housing 10 by welding or gluing, so as to seal the receiving cavity 11.

[0047] In some embodiments, the housing 10 can be formed by punching a metal sheet. The thickness of the metal sheet can be 0.1 mm to 0.4 mm to improve the punching strength of the housing 10. The metal sheet can be made of an electrically conductive metal material such as aluminum, steel, stainless steel, nickel, copper, or magnesium alloy. In this way, the housing 10 can be used as a positive electrode or a negative electrode of the cylindrical battery 100. For example, the electrode assembly 20 is directly connected to the second end portion 13 of the housing 10, so that the housing 10 itself can be used as a positive electrode or a negative electrode of the cylindrical battery 100. It should be noted that the connection can be direct or indirect.

[0048] The electrode assembly 20 includes a positive electrode sheet 21, a separator 23, and a negative electrode sheet 22. The separator 23, the positive electrode sheet 21, the separator 23, and the negative electrode sheet 22 are sequentially stacked and wound to form a cylindrical wound electrode assembly 20. The separator 23 is disposed between the positive electrode sheet 21 and the negative electrode sheet 22 to insulate and separate them. The electrode assembly 20 is accommodated in the housing 10. In other embodiments, the positive electrode sheet 21, the separator 23, the negative electrode sheet 22, and the separator 23 are sequentially stacked and wound to form a cylindrical wound electrode assembly 20.

[0049] Optionally, the positive electrode tab 21 of the electrode assembly 20 is electrically connected with the cover plate assembly 30, so that the cover plate assembly 30 leads out a positive electrode terminal, and the negative electrode tab 22 of the electrode assembly 20 is electrically connected with the second end portion 13 of the shell 10, so that the second end portion 13 of the shell 10 leads out a negative electrode terminal.

[0050] For example, the negative electrode tab 22 of the electrode assembly 20 is connected with a plurality of negative electrode tabs (not shown in the figure) or a blank foil area (not shown in the figure) without a material layer, the negative electrode tabs or the blank foil area are arranged to face the second end portion 13, the negative electrode tabs or the blank foil area are flattened to form a negative electrode flattened surface, the second end portion 13 is directly electrically connected with the negative electrode flattened surface through penetration welding, and then the second end portion 13 leads out a negative electrode terminal. The positive electrode of the electrode assembly 20 can also be arranged in a similar manner, the positive electrode tabs (not shown in the figure) or the blank foil area (not shown in the figure) without a material layer of the positive electrode tab 21 are flattened to form a positive electrode flattened surface, and the cover plate assembly 30 is electrically connected with the positive electrode flattened surface, so that the cover plate assembly 30 leads out a positive electrode terminal.

[0051] In other embodiments, the second end portion 13 can also lead out a positive electrode terminal, and the cover plate assembly 30 leads out a negative electrode terminal, which is not limited in the present application.

[0052] For the cover plate assembly 30, after the electrode assembly 20 is arranged in the shell 10, the cover plate assembly 30 can be directly connected with the shell 10 to seal the opening 12 of the first end portion of the shell 10, so that the shell 10 and the cover plate assembly 30 jointly form the accommodation cavity 11.

[0053] The cover plate assembly 30 can be electrically connected with the positive electrode tabs of the electrode assembly 20 or the positive electrode flattened surface formed by the positive electrode tabs, to lead out a positive electrode terminal. In other embodiments, referring to FIG. 1 and FIG. 4, the cover plate assembly 30 includes a pole 31 and a plate body 32, the pole 31 is arranged in the plate body 32, and the pole 31 is electrically connected with the positive electrode flattened surface, so that the pole 31 leads out a positive electrode terminal. The cover plate assembly 30 and the shell 10 or the pole 31 and the shell 10 or the pole 31 and the plate body 32 are in an insulating and sealed form, so that the cylindrical battery 100 is insulated between the positive electrode and the negative electrode.

[0054] In other embodiments, the cover plate assembly 30 can also be provided with a liquid injection hole (not shown in the figure), the liquid injection hole is communicated with the accommodation cavity 11, and electrolyte can enter the accommodation cavity 11 through the liquid injection hole to react with the electrode assembly 20 in the accommodation cavity 11, and then the liquid injection hole is sealed, so that the entire accommodation cavity 11 is sealed.

[0055] The cover plate assembly 30 is also usually provided with a power-off device or pressure relief valve, etc. When the cylindrical battery 100 produces gas rapidly, the internal pressure increases, and then impacts the power-off device or pressure relief valve, etc. to make the cylindrical battery 100 power off or pressure relief, thereby reducing the risk of explosion of the cylindrical battery 100.

[0056] For the above-mentioned current collector plate 40, please refer to FIG. 1. The current collector plate 40 is arranged in the shell 10, and the current collector plate 40 is electrically connected between the electrode assembly 20 and the cover plate assembly 30, for example, the one side of the current collector plate 40 is electrically connected with the electrode assembly 20 by welding or conductive adhesive bonding, and the other side of the current collector plate 40 is connected with the cover plate assembly 30 or the pole 31 of the cover plate assembly 30.

[0057] The arrangement of the current collector plate 40 can effectively collect the current generated inside the cylindrical battery 100 and uniformly and efficiently conduct it to the external circuit, ensuring that the current can be stably and smoothly output, improving the performance and efficiency of the cylindrical battery 100. For example, in high discharge rate applications, the current collector plate 40 can quickly collect and transfer a large amount of current to meet the demand of large rate charge and discharge of the cylindrical battery 100. Moreover, the current collector plate 40 can reduce the transmission resistance of the current inside the cylindrical battery 100, thereby reducing energy loss. The current collector plate 40 can be made of high-conductivity materials such as copper or aluminum, which can effectively reduce the resistance and improve the output power of the cylindrical battery 100. In addition, the current collector plate 40 can provide certain mechanical support for the electrode assembly 20, increasing the overall structural strength and stability of the cylindrical battery 100. When the cylindrical battery 100 is subjected to external forces such as vibration and impact, the current collector plate 40 can reduce the deformation and damage of the electrode assembly 20. At the same time, the current collector plate 40 provides a more convenient connection point, making the connection between the electrode assembly 20 and the cover plate assembly 30 more simple and reliable.

[0058] Please refer to FIG. 2, FIG. 4 and FIG. 5, the current collector plate 40 includes a first portion 41, a second portion 42 and a third portion 43, which are sequentially arranged along the first direction Z, and the second portion 42 is connected between the first portion 41 and the third portion 43. For example, along the third direction Y, one end of the second portion 42 is connected with the first portion 41, and the other end of the second portion 42 is connected with the third portion 43, which makes the current collector plate 40 form a three-layer folded structure. The three-layer folded structure can facilitate the electrical connection of the current collector plate 40 with the electrode assembly 20 and with the cover plate assembly 30 or the pole 31. For example, initially, the current collector plate 40 can be arranged in a half-folded state, after the first portion 41 is electrically connected with the electrode assembly 20, the second portion 42 and the third portion 43 can be extended out of the shell 10 through the opening 12 of the shell 10, after the third portion 43 is electrically connected with the cover plate assembly 30 outside the shell 10, the cover plate assembly 30 is sealed to the opening 12 and presses the current collector plate 40 downward, thereby directly forming a three-layer folded structure of the current collector plate 40. For the current collector plate 40 with a two-layer folded structure, due to the limitation of the angle and space, it is usually difficult to connect the current collector plate 40, which affects the installation efficiency.

[0059] In the implementation of the present application, please refer to FIG. 1, FIG. 6 and FIG. 7, wherein FIG. 6 shows the structure of the current collector plate 40 without folding, and FIG. 7 shows the folded structure of the current collector plate 40. The first portion 41 is provided with a first through hole 411, and the first portion 41 serves as the part electrically connected with the electrode assembly 20, and the gas inside the shell 10 can impact the disconnection device (such as CID) or pressure relief valve of the cover plate assembly 30 through the first through hole 411. The second portion 42 is provided with a second through hole 421, and after folding, the second through hole 421 at least partially overlaps with the first through hole 411 along the first direction Z, which makes the first through hole 411 and the second through hole 421 form a gas discharge channel. When the cylindrical battery 100 is in a limit working condition, such as short circuit or thermal runaway, etc., the gas inside the battery rapidly generates, which can rapidly impact the disconnection device (such as CID) or pressure relief valve of the cover plate assembly 30 through the first through hole 411 and the second through hole 421, so that the gas triggers the disconnection device (such as CID) or pressure relief valve of the cover plate assembly 30 in the limit working condition, thereby rapidly disconnecting the power or discharging the gas, and reducing the risk of explosion of the cylindrical battery 100.

[0060] Meanwhile, the first through hole 411 and the second through hole 421 can serve as electrolyte transmission channels. During the electrolyte injection process of the cylindrical battery 100, the electrolyte injected through the electrolyte injection hole of the cover plate assembly 30 can be directly transmitted to the electrode assembly 20 through the first through hole 411 and the second through hole 421, which can shorten the electrolyte transmission path, enable the electrode assembly 20 to be more quickly and fully soaked by the electrolyte, and improve the electrolyte injection efficiency and the soaking efficiency of the electrolyte. Alternatively, the electrolyte that is free in the shell 10 can also directly enter the electrode assembly 20 through the first through hole 411 and the second through hole 421, which can more quickly and fully soak the electrode assembly 20, is conducive to the full performance of the electrochemical reaction, and saves the formation time.

[0061] Please further refer to FIGS. 2 and 4. The electrode assembly 20 forms a central hole 24 after being wound, and the internal gas can be discharged through the central hole 24. In the embodiment of the present application, the second through hole 421, the first through hole 411, and the central hole 24 at least partially overlap along the first direction Z, so that the second through hole 421, the first through hole 411, and the central hole 24 form a gas transmission channel. The internal gas can directly and quickly impact the disconnection device (such as a CID) or the pressure relief valve of the cover plate assembly 30 through the central hole 24, the first through hole 411, and the second through hole 421. The airflow transmission channel is larger, can adapt to a larger gas flow, is conducive to the quick triggering of the disconnection device or the pressure relief valve of the cover plate assembly 30 under extreme working conditions, and further reduces the explosion risk of the cylindrical battery 100.

[0062] Moreover, during the electrolyte injection process, the electrolyte injected from the cover plate assembly 30 can be transmitted to the central hole through the second through hole 421 and the first through hole 411. The electrolyte can be diffused at the central hole 24 towards the electrode assembly 20, that is, the electrolyte in the central hole can soak the electrode assembly 20 from the inside of the electrode assembly 20, and the electrolyte free outside can soak the electrode assembly from the outside of the electrode assembly, which improves the soaking efficiency of the electrode assembly 20 and the electrolyte injection efficiency.

[0063] In some embodiments, referring to FIG. 4 and FIG. 8, the projection of the third portion 43 overlaps with the second through hole 421 along the first direction Z. The power-off device of the cylindrical battery 100 includes an explosion-proof sheet 50, which is electrically connected to the cover plate assembly 30. The explosion-proof sheet 50 has a connecting portion 51 protruding towards the third portion 43, and the connecting portion 51 is electrically connected to the third portion 43. For example, the explosion-proof sheet 50 includes a fixed portion 52 and the connecting portion 51, which can be arranged at the center of the explosion-proof sheet 50, protrudes towards the third portion 43 and is directly in contact with the third portion 43 for electrical connection. The first space 60 is formed between the fixed portion 52, the connecting portion 51 and the third portion 43, and the second through hole 421 communicates with the first space 60. This can make the gas flowing through the second through hole 421 directly flow to the first space 60, and the gas flowing through the central hole 24 to the first through hole 411 and the second through hole 421, and then to the first space 60, so that the gas can concentrate and impact the connecting portion 51 of the explosion-proof sheet 50 in the first space 60, which can facilitate the connecting portion 51 to protrude away from the third portion 43, and thus the electrical connection between the explosion-proof sheet 50 and the third portion 43 is disabled, thereby quickly powering off and reducing the risk of explosion of the cylindrical battery 100.

[0064] In addition, the connecting portion 51 is connected to the third portion 43, so that the third portion 43 can shield the connecting portion 51, reducing the direct impact of the gas flowing through the first through hole 411 and the second through hole 421 on the connecting portion 51, and reducing the power-off of the cylindrical battery 100 under normal working conditions.

[0065] Optionally, along the first direction Z, an insulating member 70 can be arranged between the explosion-proof sheet 50 and the third portion 43 or between the explosion-proof sheet 50 and the second portion 42, for example, the insulating member 70 is arranged between the fixed portion 52 of the explosion-proof sheet 50 and the third portion 43. When the connecting portion 51 protrudes away from the third portion 43 and is disconnected from the third portion 43, the insulating member 70 can prevent the current collector 40 from moving towards the explosion-proof sheet 50, so that the current collector 40 and the explosion-proof sheet 50 are insulated.

[0066] In some other embodiments, referring to FIG. 9, the cylindrical battery 100 further includes a connecting plate 80 electrically connected between the explosion-proof sheet 50 and the third portion 43, and the connecting plate 80 and the explosion-proof sheet 50 can form an explosion-proof device. The arrangement of the connecting plate 80 can improve the current carrying capacity, effectively collect the current of the current collector 40, and uniformly and efficiently conduct the current to the explosion-proof sheet 50, ensuring that the current can be stably and smoothly output. At the same time, the arrangement of the connecting plate 80 can also reduce the direct impact of the gas on the explosion-proof sheet 50, and reduce the power-off of the cylindrical battery 100 under normal working conditions.

[0067] Optionally, the connecting plate 80 is a plate structure with various through holes, and the various through holes on the connecting plate 80 can facilitate the gas to enter the first space 60, so that when the pressure of the first space 60 reaches the predetermined threshold, the electrical connection between the rupture disc 50 and the connecting plate 80 can be disconnected.

[0068] Optionally, the above-mentioned insulating member 70 can also be arranged between the connecting plate 80 and the rupture disc 50, for example, between the fixed portion 52 of the rupture disc 50 and the connecting plate 80, and when the connecting portion 51 is disconnected from the rupture disc 50, the insulating member 70 can insulate and separate the connecting plate 80 and the rupture disc 50.

[0069] In some embodiments, the connecting plate 80 has a weak portion 81 connected with the connecting portion 51. For example, the connecting plate 80 further includes a main body portion 82, and the weak portion 81 can be connected at the center of the main body portion 82, and along the first direction Z, the thickness of the weak portion 81 is smaller than the thickness of the main body portion 82, which makes the weak portion 81 more prone to breakage. The arrangement of the weak portion 81 can facilitate the connection between the connecting portion 51 and the connecting plate 80, for example, by welding or conductive adhesive bonding, thereby improving the stability of the electrical connection. Under normal working conditions, the weak portion 81 is connected with the main body portion 82 to transmit current, and under extreme working conditions, that is, when the pressure of the first space 60 reaches the predetermined threshold, the connecting portion 51 drives the weak portion 81 to protrude away from the connecting plate 80, so that the weak portion 81 is separated from the main body portion 82, and the electrical connection between the rupture disc 50 and the connecting plate 80 is disconnected.

[0070] In some embodiments, along the first direction Z, the weak portion 81 and the third portion 43 at least partially overlap, and through the shielding of the third portion 43 to the weak portion 81, the direct impact of the gas in the second through hole 421 and the first through hole 411 on the weak portion 81 can be reduced, and the power-off of the cylindrical battery 100 under normal working conditions can be reduced.

[0071] In some embodiments, referring further to FIGS. 6 and 7, the third portion 43 is provided with a third through hole 431, and the first portion 41 is further provided with a fourth through hole 412, and along the first direction Z, the third through hole 431 at least partially overlaps with the first through hole 411 or the fourth through hole 412. As shown in FIG. 8, the gas can be directly transmitted to the third through hole 431 through the first through hole 411, or directly transmitted to the third through hole 431 through the first through hole 411 and the fourth through hole 412, and then enters the first through hole 411, thereby providing a gas transmission channel and shortening the gas transmission path, which is more conducive to triggering the above-mentioned rupture disc 50 under extreme working conditions, so that the cylindrical battery 100 can be quickly powered off. During the liquid injection stage, the electrolyte can directly reach the first through hole 411 or the fourth through hole 412 through the third through hole 431, and then quickly reach the center hole 24, thereby quickly wetting the electrode assembly 20 and improving the liquid injection efficiency.

[0072] The first through hole 411 can be in communication with the fourth through hole 412, or the first through hole 411 is provided with an extension portion 4111 to be in communication with the third through hole 431, or the first through hole 411 and the fourth through hole 412 are separately provided on the first portion 41. When separately provided, the fourth through hole 412 can also at least partially overlap the central hole 24 of the electrode assembly 20 along the first direction Z. The shape of each through hole can be circular, oval, triangular, quadrilateral, or polygonal.

[0073] In other embodiments, referring to FIG. 10 and FIG. 11, the projection of the third portion 43 on the projection of the second portion 42 along the first direction Z is within the projection of the second portion 42, and the third portion 43 does not completely cover the first through hole 411 (the dashed portion in FIG. 11 is the first through hole 411), so that the gas of the first through hole 411 can directly reach the vicinity of the explosion-proof sheet 50, for example, directly enter the first space 60 described above, further shorten the gas transmission path, reduce the explosion risk of the cylindrical battery 100, and also shorten the liquid injection path, improve the liquid injection efficiency, and improve the electrolyte infiltration efficiency.

[0074] In some embodiments, referring to FIG. 5 and FIG. 6, the surface of the first portion 41 facing the second portion 42 is provided with a plurality of first protrusions 413. When the second portion 42 is folded towards the first portion 41, the first protrusions 413 can be supported between the third portion 43 and the first portion 41 to provide a gas flow space, which is more conducive to the gas flowing through the first through hole 411 and the second through hole 421 towards the cover plate assembly 30.

[0075] In other embodiments, the surface of the third portion 43 facing the second portion 42 is provided with a plurality of second protrusions 432. When the third portion 43 is folded towards the second portion 42, the second protrusions 432 can be supported between the third portion 43 and the second portion 42 to provide a gas transmission space, which is more conducive to the rapid transmission of the gas to the vicinity of the explosion-proof sheet 50, further reducing the explosion risk of the cylindrical battery 100.

[0076] At the same time, the provision of the first protrusions 413 and the second protrusions 432 can also provide an electrolyte transmission space between the first portion 41 and the second portion 42, and an electrolyte transmission space between the third portion 43 and the second portion 42, which can better accommodate the large-dose injection of electrolyte and improve the liquid injection efficiency. The first protrusions 413 and the second protrusions 432 can also be provided on the second portion 42.

[0077] When the first portion 41, the second portion 42, and the third portion 43 of the current collector plate 40 are not folded, the current collector plate 40 as a whole is in a sheet shape, and a plurality of current collector plates 40 can be stacked. The provision of the first protrusions 413 and / or the second protrusions 432 can form several spaces between adjacent two current collector plates 40, which can facilitate the taking and placing of the current collector plates 40.

[0078] In some embodiments, referring to FIG. 12, the maximum dimension of the outer contour of the first through hole 411 is D1, the maximum dimension of the outer contour of the second through hole 421 is D2, 50%≤D2 / D1≤95%, it can be understood that the maximum dimension refers to the maximum distance between any two points of the outer contour. D2 / D1≥50% enables the gas flowing through the first through hole 411 to be quickly transmitted to the second through hole 421 and to the explosion-proof sheet 50, D2 / D1≤95% can reduce the assembly tolerance problem, and D2 / D1≤95% can also reduce the influence of the current-carrying problem caused by the setting of the second through hole 421 on the second part 42, so that the current collector plate 40 still has high current-carrying capacity and improves the power output of the cylindrical battery 100. Preferably, 70%≤D2 / D1≤90%, which further reduces the assembly tolerance problem while improving the current-carrying capacity of the current collector plate 40.

[0079] In some embodiments, referring to FIG. 12, along the second direction X, the width of the second part 42 is W2, 5%≤D2 / W2≤30%, and the maximum dimension of the outer contour of the second through hole 421 is too large, which can easily lead to weak strength of the second part 42 and reduce the flow area of the second part 42. Limiting 5%≤D2 / W2≤30% can reduce the influence of the second through hole 421 on the current-carrying capacity of the second part 42 while making the second part 42 have high strength, thereby improving the power output of the cylindrical battery 100. Wherein, the first direction Z, the second direction X and the third direction Y are perpendicular to each other.

[0080] In some embodiments, along the second direction X, the maximum width of the first part 41 is W1, the maximum width of the second part 42 is W2, 40%≤W2 / W1≤80%, which improves the current-carrying capacity of the first part 41 and the second part 42 while making the current collector plate 40 have high strength, facilitating the folding between the first part 41 and the second part 42 and reducing the breaking phenomenon during folding. Optionally, the maximum width of the third part 43 is W3, 30%≤W3 / W1≤80%, which improves the current-carrying capacity of the third part 43 and the second part 42 and reduces the breaking phenomenon between the second part 42 and the third part 43.

[0081] In other embodiments, along the third direction Y, the maximum length of the first part 41 is L1, the maximum length of the second part 42 is L2, and the maximum length of the third part 43 is L3, 60%≤L2 / L1≤100%, 60%≤L3 / L2≤100%. Further improve the current-carrying capacity of the current collector plate 40 while making the current collector plate 40 have high strength, facilitating the folding of the first part 41, the second part 42 and the third part 43, and reducing the risk of folding fracture.

[0082] The second aspect of the present application also provides an electronic device comprising the cylindrical battery 100 according to any one of the embodiments of the first aspect. The electronic device according to the embodiments of the present application is not particularly limited and can be any electronic device known in the art. For example, the electronic device includes but is not limited to a Bluetooth headset, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, an electric vehicle, an electric car, a ship, a spacecraft, etc. Among them, the electric toy can include a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, an electric plane toy, etc., and the spacecraft can include an airplane, a rocket, a space shuttle, a spacecraft, etc.

[0083] The third aspect of the present application provides a current collector plate 40 applied to the cylindrical battery 100 according to any one of the embodiments of the first aspect. Please refer to FIG. 13, which shows the unfolded state (unfolding state) of the current collector plate 40. The current collector plate 40 comprises a first part 41, a second part 42 and a third part 43, and the second part 42 is connected between the first part 41 and the third part 43.

[0084] The connection between the first part 41 and the second part 42 has a first connection section 44. The first part 41 is provided with a first through hole 411, and the second part 42 is provided with a second through hole 421, and the maximum dimension of the outer contour of the second through hole 421 is D2. Along the length direction (third direction Y, the length direction of the current collector plate 40 in the unfolded state) of the current collector plate 40, the projection of the first through hole 411 and the projection of the second through hole 421 at least partially overlap, the distance from the first connection section 44 to the first through hole 411 is M, the distance from the first connection section 44 to the second through hole 421 is N, and N≤M<N+D2.

[0085] When the current collector plate 40 is not in use, it is in the unfolded state, i.e. the state shown in FIG. 13. When the current collector plate 40 is applied to the cylindrical battery 100, the first part 41 needs to be folded along its length direction, for example, folded towards the second part 42 along the first connection section 44. Because N≤M<N+D2, after folding, the second through hole 421 and the first through hole 411 at least partially overlap along the first direction Z (the thickness direction of the current collector plate 40), and the first through hole 411 and the second through hole 421 form a gas discharge channel. When the cylindrical battery 100 is in a limit working condition, for example, short circuit or thermal runaway, etc., gas is rapidly generated inside the cylindrical battery 100. The gas can be discharged through the first through hole 411 and the second through hole 421 towards the cover plate assembly 30, so that the gas can concentrate near the cover plate assembly 30 and impact the cover plate assembly 30, which is more convenient to trigger the power-off device or pressure relief valve of the cover plate assembly 30 in the limit working condition, so as to quickly power off or discharge the gas, thereby reducing the risk of explosion of the cylindrical battery 100.

[0086] Meanwhile, the first through hole 411 and the second through hole 421 can serve as electrolyte transport channels. In the electrolyte injection process of the cylindrical battery 100, the electrolyte injected through the cover plate assembly 30 can be directly transported to the electrolyte assembly through the first through hole 411 and the second through hole 421, which can shorten the electrolyte flow path and make it easier for the electrode assembly 20 to be fully wetted by the electrolyte, thereby improving the injection efficiency. Alternatively, the free electrolyte in the casing 10 can also directly and quickly enter the electrode assembly 20 through the first through hole 411 and the second through hole 421, which can quickly and fully wet the electrode assembly 20, which is conducive to the full progress of the electrochemical reaction and saves the battery formation time.

[0087] Experiment 1: Preparation of Lithium-ion Cylindrical Batteries

[0088] Example 1

[0089] <Preparation of the positive electrode>:

[0090] The positive electrode active material is lithium iron phosphate, the positive electrode conductive agent is acetylene black, and the positive electrode binder is polyvinylidene fluoride (PVDF, with a weight average molecular weight of 5×10⁻⁶). 5 The materials were mixed at a mass ratio of 94:3:3, with N-methylpyrrolidone (NMP) added as a solvent to prepare a positive electrode slurry with a solid content of 75 wt%. The slurry was then stirred uniformly under vacuum. A 10 μm thick aluminum foil was used as the positive electrode current collector. The positive electrode slurry was uniformly coated onto one surface of the aluminum foil, leaving an uncoated area. The foil was dried at 110°C to obtain a positive electrode sheet with a single-sided coating of the positive active material layer. The above steps were then repeated on the other surface of the aluminum foil to obtain a positive electrode sheet with a double-sided coating of the positive active material layer. The coating weight of the positive electrode sheet was 22.33 mg / cm³. 2 .

[0091] <Preparation of Negative Electrode Sheets>

[0092] Graphite powder (negative electrode active material), conductive carbon black (Super P) (conductive agent), and styrene-butadiene rubber (SBR) (binder) were mixed in a weight ratio of 97.5:1:1.5. Deionized water was then added as a solvent to prepare a negative electrode slurry with a solid content of 50 wt%, and the mixture was stirred evenly. A 6 μm thick copper foil was used as the negative electrode current collector. The negative electrode slurry was uniformly coated onto one surface of the copper foil, leaving an uncoated area. The foil was dried at 90°C to obtain a single-sided negative electrode sheet. This completes the single-sided coating of the negative electrode sheet. The same steps were then repeated on the other surface of the negative electrode sheet to obtain a double-sided coated negative electrode sheet. The coating weight of the negative electrode sheet was 6.64 mg / cm³. 2 ...

[0093] Preparation of the separator film

[0094] A polyethylene (PE) porous film with a thickness of 8 μm was used as the separator film.

[0095] Preparation of the electrolyte

[0096] Vinyl carbonate, methyl ethyl carbonate and diethyl carbonate were mixed in a mass ratio of 30:50:20 to obtain an organic solution in a dry argon atmosphere, and then lithium salt lithium hexafluorophosphate was added to the organic solvent to dissolve and mix uniformly, to obtain an electrolyte with a lithium salt concentration of 1.15 mol / L.

[0097] Preparation of the lithium ion battery

[0098] The separator film, the positive electrode sheet, the separator film, and the negative electrode sheet prepared above were stacked in order and wound to obtain an electrode assembly. The electrode assembly was subjected to heat pressing (pressure 5 MPa, temperature 65 °C, pressure maintaining time 10 s). The positive electrode blank area was flattened to form a positive electrode flattened surface, and the negative electrode blank area was flattened to form a negative electrode flattened surface. The center hole was exposed on each flattened surface, and the electrode assembly was placed in a cylindrical steel shell. A three-layer folded current collector was used, and the three layers were a first part, a second part, and a third part. The first part had a first through hole, and the second part had a second through hole. The first part of the current collector was welded to the positive electrode flattened surface, and the first through hole overlapped with the center hole. After the second part was folded towards the first part along the cylindrical battery axis Z, the second through hole fell within the range of the first through hole, and the diameter D2 of the second through hole was 30% of the diameter D1 of the first through hole (D2 / D1 = 30%).

[0099] The third part was welded to the pole of the cover plate assembly through the explosion-proof sheet to lead out the positive electrode terminal. The negative electrode flattened surface was resistance welded to the bottom of the shell through another current collector to lead out the negative electrode terminal. After removing the water at 80 °C, the electrolyte was injected and the heat shrinkable film was sleeved.

[0100] The relevant parameters in Comparative Example 1 and Examples 2 to 9 are shown in Table 1.

[0101] Short circuit test method: a resistor (5 mOhm) was used to form a circuit with each cylindrical battery of the examples and comparative examples, and the circuit was closed for a certain time (10 min). If the cylindrical battery caught fire, burned, or exploded, it was considered to be a test failure.

[0102] The relevant parameters in Comparative Example 1 and Examples 2 to 9 are shown in Table 1.

[0103] Table 1

[0104] According to the above Table 1, in combination with the above Examples 1 to 9 and Comparative Example 1, when the second through hole is arranged in the second part and overlaps with the first through hole, the short circuit test failure rate can be reduced, because the first through hole and the second through hole form a gas flow channel, when a large amount of gas is rapidly generated inside the cylindrical battery under extreme working conditions, the gas can flow rapidly towards the cover plate assembly through the first through hole and the second through hole, so that the gas concentrates and impacts the rupture disc or the explosion valve near the cover plate assembly, which is more convenient to trigger the rupture disc or the explosion valve on the cover plate assembly under extreme working conditions, so as to quickly cut off the power or discharge the gas, thereby reducing the explosion risk of the cylindrical battery.

[0105] In Examples 3 to 9, the short circuit test failure rate is better than that of Examples 1 and 2, because the size of the second through hole is larger, which provides a larger gas flow channel, so that the gas flow can reach the vicinity of the rupture disc in a short time, which can quickly cut off the power and reduce the swelling and explosion risk of the cylindrical battery. Therefore, in the present application, 50%≤D2 / D1≤100% can be selected, and in Example 9, it is difficult to completely fold the second through hole with the first through hole when folding, the size of the second through hole is too large, which affects the impedance of the second part, so that the current carrying capacity of the second part is weakened, and the short circuit test failure rate of Example 8 is consistent with that of Example 9, therefore, in another embodiment of the present application, 50%≤D2 / D1≤95% can be selected.

[0106] Compared with Example 7, the short circuit test failure rate of Examples 8 and 9 is not significantly reduced, and the size of the second through hole is too large, which affects the current carrying capacity of the second part. Compared with Examples 3 and 4, the short circuit test failure rate of Examples 5 and 6 is reduced more obviously, therefore, in the present application, 70%≤D2 / D1≤90% is preferred.

[0107] The above is only an embodiment of the present application, and does not limit the patent scope of the present application, any equivalent structure or equivalent flow transformation using the content of the present application specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A cylindrical battery comprising a case, a cover plate assembly, a current collector plate, and an electrode assembly, the case and the cover plate assembly enclosing a receiving cavity, the electrode assembly and the current collector plate being provided in the receiving cavity, the current collector plate being provided between the electrode assembly and the cover plate assembly, characterized in that, The current collecting plate comprises a first portion, a second portion and a third portion; The first portion, the second portion and the third portion are arranged in sequence along a first direction, the second portion is connected between the first portion and the third portion, the first portion is electrically connected with the electrode assembly, and the third portion is connected with the cover plate assembly; The first portion is provided with a first through hole, and the second portion is provided with a second through hole, and the second through hole and the first through hole at least partially overlap along the first direction.

2. The cylindrical battery according to claim 1, characterized by The electrode assembly has a center hole, and the second through hole, the first through hole and the center hole at least partially overlap along the first direction.

3. The cylindrical battery according to claim 1 or 2, characterized by, The projection of the third portion overlaps the second through hole along the first direction. The cylindrical battery further comprises an anti-explosion sheet, and the anti-explosion sheet is electrically connected with the cover plate assembly. The anti-explosion sheet has a connecting portion protruding towards the third portion, and the connecting portion is electrically connected with the third portion. The anti-explosion sheet and the third portion have a first space therebetween, and the second through hole communicates with the first space.

4. The cylindrical battery according to any one of claims 1 to 3, characterized by, The cylindrical battery further comprises a connecting plate, and the connecting plate is electrically connected between the anti-explosion sheet and the third portion. The connecting plate has a weak portion, and the weak portion is connected with the connecting portion.

5. The cylindrical battery according to any one of claims 1 to 4, characterized by, The weak portion and the third portion at least partially overlap along the first direction.

6. The cylindrical battery according to any one of claims 1 to 5, characterized by, The third portion is provided with a third through hole, and the first portion is further provided with a fourth through hole, and the third through hole at least partially overlaps with the first through hole or the fourth through hole along the first direction.

7. The cylindrical battery according to any one of claims 1 to 6, characterized by, The projection of the third portion is within the projection of the second portion along the first direction, and the third portion does not completely cover the first through hole.

8. The cylindrical battery according to any one of claims 1 to 7, characterized by, The first portion is provided with a first protruding portion on the surface facing the second portion, and / or the third portion is provided with a second protruding portion on the surface facing the second portion.

9. The cylindrical battery according to any one of claims 1 to 8, characterized by, The maximum size of the outer contour of the first through hole is D1, and the maximum size of the outer contour of the second through hole is D2, and 50%≤D2 / D1≤95%.

10. The cylindrical battery of claim 9, wherein, 70%≤D2 / D1≤90%.

11. The cylindrical battery according to claim 9 or 10, characterized by Along a second direction, the width of the second portion is W2, and 5%≤D2 / W2≤30%; The first direction and the second direction are perpendicular to each other.

12. The cylindrical battery according to any one of claims 1 to 11, characterized by, Along a second direction, the maximum width of the first portion is W1, the maximum width of the second portion is W2, and the maximum width of the third portion is W3, 40%≤W2 / W1≤80%, 30%≤W3 / W1≤80%, and the first direction and the second direction are perpendicular to each other.

13. The cylindrical battery according to any one of claims 1 to 12, characterized by, Along a third direction, the maximum length of the first portion is L1, the maximum length of the second portion is L2, and the maximum length of the third portion is L3, 60%≤L2 / L1≤100%, 60%≤L3 / L2≤100%; The first direction and the third direction are perpendicular to each other.

14. An electronic device, comprising: The cylindrical battery comprises the cylindrical battery as claimed in any one of claims 1 to 13. The cylindrical battery comprises the cylindrical battery as claimed in any one of claims 1 to 13.

15. A current collector plate applied to the cylindrical battery according to any one of claims 1 to 13, characterized by, The current collecting plate comprises a first portion, a second portion and a third portion, the second portion is connected between the first portion and the third portion, and the first portion and the second portion are connected at a first connecting section; The first portion is provided with a first through hole, and the second portion is provided with a second through hole, and the maximum dimension of the outer contour of the second through hole is D2; In the length direction of the current collecting plate, the projection of the first through hole and the projection of the second through hole at least partially overlap, the distance from the first connecting section to the first through hole is M, the distance from the first connecting section to the second through hole is N, and N≤M<N+D2.

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