Cylindrical battery cell structure

Abstract

The utility model relates to the technical field of battery cells, and discloses a cylindrical battery cell structure which comprises a battery cell shell and is characterized in that a cover plate is arranged at the top of the battery cell shell; the cover plate is provided with a positive pole, a negative pole, a liquid injection port and an anti-explosion valve; a negative electrode confluence plate which is positioned at the inner top of the battery cell shell and is electrically connected with the negative electrode post; the positive electrode confluence plate is positioned at the inner bottom of the battery cell shell; and the roll core is located between the negative pole confluence disc and the positive pole confluence disc, a negative pole piece of the roll core is electrically connected with the negative pole confluence disc, and a positive pole piece of the roll core is electrically connected with the positive pole confluence disc and the positive pole column.

Description

Technical Field

[0001] The utility model relates to the technical field of battery cores, and specifically to a cylindrical battery core structure. Background Art

[0002] The battery cell refers to the core component of the battery, also known as the battery chip or battery monomer; it is the main energy storage unit of the battery, which can convert chemical energy into electrical energy and release electrical energy when needed; the battery cell is usually composed of a positive electrode, a negative electrode, an electrolyte and a separator; different types of batteries have different battery cell structures, such as lithium-ion batteries, nickel-metal hydride batteries, etc.; the quality and performance of the battery cell directly affect important indicators such as battery capacity, charge and discharge rate, and cycle life; the market has put forward higher requirements for lithium batteries, and taking into account high energy density, lower cost and higher production efficiency has become a technical challenge;

[0003] The technical problem to be solved by the utility model is to provide a more compact cylindrical battery core structure. Utility Model Content

[0004] The technical problem to be solved by the utility model is: to provide a more compact cylindrical battery cell structure; its negative busbar is located at the top of the battery cell shell, connected to the negative pole column, and used to collect the negative current of the battery; the positive busbar is located at the bottom of the battery cell shell, and used to collect the positive current of the battery; the negative electrode sheet of the winding core is connected to the negative busbar, and used to derive the negative current; the positive electrode sheet of the winding core is connected to the positive busbar and the positive pole column, and used to derive the positive current; the positive pole column, the negative pole column, the injection port, and the explosion-proof valve are all located on the cover plate, that is, the cover plate is highly integrated, with the advantages of lower cost and higher production efficiency, the battery cell is larger than the current mainstream 4680, so that the proportion of inactive components such as the inner shell and the outer shell per unit volume is relatively reduced, and the battery cell has a higher energy density.

[0005] A cylindrical battery cell structure includes a battery cell shell, characterized in that a cover plate is provided on the top of the battery cell shell; and a positive pole column, a negative pole column, a liquid injection port, and an explosion-proof valve are provided on the cover plate; and the interior of the battery cell shell is provided with: a negative busbar, located at the inner top of the battery cell shell and electrically connected to the negative pole column; a positive busbar, located at the inner bottom of the battery cell shell; a winding core, located between the negative busbar and the positive busbar, the negative electrode sheet of the winding core is electrically connected to the negative busbar, and the positive electrode sheet of the winding core is electrically connected to the positive busbar and the positive pole column.

[0006] Preferably, the positive electrode busbar includes a positive electrode disc body; and the top of the positive electrode disc body is formed with six positive electrode protrusion strips arranged at equal intervals around it; and positive electrode through holes penetrating the positive electrode disc body are formed between the positive electrode protrusion strips; and the center position of the positive electrode disc body is formed with an annular groove position for being embedded and fixed with the bottom of the battery cell shell.

[0007] Preferably, the negative electrode busbar includes a negative electrode disc body; and three V-shaped negative electrode protrusion strips are formed at intervals on the bottom of the negative electrode disc body; and a plurality of negative electrode through holes are formed through the top of the negative electrode disc body.

[0008] Preferably, a copper nail is provided on the cover plate, and the negative electrode post and the copper nail are electrically connected by laser welding; the positive electrode post is stamped by the cover plate and is symmetrically arranged with the negative electrode post.

[0009] Preferably, an outer wall of the copper nail is sleeved with an outer insulating pad and a sealing ring; and an inner insulating pad is provided under the positive pole; and the inner insulating pad and the outer insulating pad separate the positive pole from the negative pole.

[0010] Preferably, laser welding is used between the negative electrode busbar and the copper nails and the negative electrode sheet of the winding core; laser welding is used between the positive electrode collector and the positive electrode ear of the winding core; laser welding is used between the cover plate and the top of the battery cell shell; and penetration welding is used between the positive electrode collector and the inner bottom of the battery cell shell.

[0011] Preferably, the liquid injection port is arranged on the cover plate and is located between the positive electrode column and the negative electrode column; and the explosion-proof valve includes an explosion-proof plate fixed to the cover plate and an explosion-proof patch bonded to the explosion-proof plate.

[0012] Preferably, a first separator is provided between the positive electrode sheet and the negative electrode sheet of the winding core; and a second separator is provided on the other side of the positive electrode sheet of the winding core; and the negative electrode sheet, the first separator, the positive electrode sheet and the second separator are wound to form the winding core.

[0013] Preferably, the thickness of the positive busbar is 0.1 to 0.5 mm; the thickness of the negative busbar is 0.1 to 0.5 mm, the diameter of the battery cell shell is 50 to 70 mm, and the height is 80 to 200 mm.

[0014] Preferably, the material used for the positive electrode sheet of the winding core is one of lithium iron phosphate, lithium iron manganese phosphate, ternary material, and sodium ion positive electrode material, and the material used for the negative electrode sheet is one of graphite, silicon carbon, and hard carbon.

[0015] Compared with the prior art, the beneficial effects of the utility model are as follows: in the cylindrical battery cell structure of the utility model, the negative busbar is located at the top of the battery cell shell and is connected to the negative electrode column to collect the negative current of the battery; the positive busbar is located at the bottom of the battery cell shell to collect the positive current of the battery; the negative electrode sheet of the winding core is connected to the negative busbar to derive the negative current; the positive electrode sheet of the winding core is connected to the positive busbar and the positive electrode column to derive the positive current; the positive electrode column, the negative electrode column, the injection port and the explosion-proof valve are all located on the cover plate, that is, the high integration of the cover plate has the advantages of lower cost and higher production efficiency, the battery cell is larger than the current mainstream 4680, so that the proportion of inactive components such as the inner and outer shells per unit volume is relatively reduced, and the battery cell has a higher energy density.

[0016] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0018] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0019] Figure 2 This utility model Figure 1 Schematic diagram of the half-section structure.

[0020] Figure 3 This utility model Figure 2 A is an enlarged structural diagram of FIG.

[0021] Figure 4 It is a schematic diagram of the cover structure of the utility model.

[0022] Figure 5 It is a schematic diagram of the structure of the negative electrode busbar of the utility model.

[0023] Figure 6 It is a schematic diagram of the structure of the positive busbar of the utility model.

[0024] Figure 7 It is a schematic diagram of the winding core structure of the utility model.

[0025] In the figure: 1. battery cell shell; 2. cover plate; 3. positive electrode column; 4. negative electrode column; 5. injection port; 6. explosion-proof valve; 7. negative electrode busbar; 8. positive electrode busbar; 9. winding core; 10. positive electrode plate; 11. positive electrode protrusion strip; 12. positive electrode through hole; 13. annular groove position; 14. negative electrode plate; 15. negative electrode protrusion strip; 16. negative electrode through hole; 17. copper nail; 18. outer insulating pad; 19. sealing ring; 20. inner insulating pad; 21. explosion-proof plate; 22. explosion-proof patch; 23. positive electrode sheet; 24. negative electrode sheet; 25. first diaphragm; 26. second diaphragm. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that the terms "first", "second", etc. in the present invention are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure.

[0028] See also Figures 1 to 7 In the embodiment of the utility model, a cylindrical battery cell structure includes a battery cell shell 1; a cover plate 2 is provided on the top of the battery cell shell 1; and a positive pole column 3, a negative pole column 4, a liquid injection port 5, and an explosion-proof valve 6 are provided on the cover plate 2; and the interior of the battery cell shell 1 is provided with: a negative busbar 7, which is located at the inner top of the battery cell shell 1 and is electrically connected to the negative pole column 4; a positive busbar 8, which is located at the inner bottom of the battery cell shell 1; a winding core 9, which is located between the negative busbar 7 and the positive busbar 8, the negative electrode sheet 24 of the winding core 9 is electrically connected to the negative busbar 7, and the positive electrode sheet 23 of the winding core 9 is electrically connected to the positive busbar 8 and the positive pole column 3.

[0029] Specifically, the battery cell shell 1 is the outer shell of the battery, which is used to accommodate the internal components of the battery and provide protection and structural support; the cover plate 2 is a plate-shaped component located on the top of the battery cell shell 1, which is used to seal the battery cell shell 1; the positive electrode column 3 and the negative electrode column 4 are the polarity terminals of the battery, which are used to connect the battery to the external circuit; the injection port 5 is used to inject electrolyte or other liquids during the battery manufacturing process; the explosion-proof valve 6 is used to prevent the battery from exploding or leaking due to excessive pressure under abnormal conditions; the negative busbar 7 is located at the top of the battery cell shell 1, connected to the negative electrode column 4, and is used to collect the negative current of the battery; the positive busbar 8 is located at the bottom of the battery cell shell 1, and is used to collect the positive current of the battery; the winding core 9 is the main energy storage part of the battery, which is composed of a series of stacked positive and negative electrode materials; the negative electrode sheet 24 of the winding core 9 is connected to the negative electrode busbar 7 for deriving the negative current; the positive electrode sheet 23 of the winding core 9 is connected to the positive busbar 8 and the positive electrode column 3 for deriving the positive current;

[0030] The positive electrode column 3, the negative electrode column 4, the liquid injection port 5, and the explosion-proof valve 6 are all located on the cover plate 2, that is, the cover plate 2 is highly integrated, with the advantages of lower cost and higher production efficiency. The battery cell is larger than the current mainstream 4680, which makes the proportion of inactive components such as the inner and outer shells per unit volume relatively reduced, and the battery cell has a higher energy density.

[0031] Furthermore, a copper nail 17 is provided on the cover plate 2 , and the negative electrode post 4 and the copper nail 17 are electrically connected by laser welding; the positive electrode post 3 is stamped by the cover plate 2 and is symmetrically arranged with the negative electrode post 4 .

[0032] Specifically, the copper nail 17 is installed on the cover plate 2 and serves as a conductive connector connecting the negative electrode post 4; copper is a good conductive material that can ensure good transmission of current; laser welding is used to connect the negative electrode post 4 with the copper nail 17 to ensure good electrical connection; laser welding can provide highly precise welding, ensure a stable connection and reduce resistance; the positive electrode post 3 is made by stamping the cover plate 2, providing an economical and efficient way to produce the positive electrode post 3, and is symmetrically arranged with the negative electrode post 4 to ensure the balance and stability of the battery structure.

[0033] Furthermore, an outer wall of the copper nail 17 is sleeved with an outer insulating pad 18 and a sealing ring 19; an inner insulating pad 20 is provided below the positive electrode column 3; and the inner insulating pad 20 and the outer insulating pad 18 separate the positive electrode column 3 from the negative electrode column 4.

[0034] Specifically, the outer insulating pad 18 and the sealing ring 19 are located outside the outer wall of the copper nail 17 to provide additional electrical insulation and sealing; the outer insulating pad 18 can ensure the insulation between the negative electrode column 4 and the battery casing, while the sealing ring 19 can prevent the leakage of electrolyte inside the battery or the entry of external impurities; the inner insulating pad 20 is an insulating material located under the positive electrode column 3, which is used to separate the positive electrode column 3 from the negative electrode column 4; the presence of the inner insulating pad 20 can prevent short circuits between the positive and negative electrodes and ensure the normal operation of the battery.

[0035] Furthermore, the liquid injection port 5 is provided on the cover plate 2 and is located between the positive electrode column 3 and the negative electrode column 4; and the explosion-proof valve 6 includes an explosion-proof plate 21 fixed to the cover plate 2 and an explosion-proof patch 22 bonded to the explosion-proof plate 21 .

[0036] Specifically, the injection port 5 is located on the cover plate 2 and between the positive electrode column 3 and the negative electrode column 4; this position is selected to facilitate the injection of electrolyte or other liquids during assembly and maintenance; setting the injection port 5 between the positive and negative electrodes helps to ensure uniform distribution of the liquid and reduce the possibility of air gaps or air bubbles; the explosion-proof valve 6 includes two main components: the explosion-proof plate 21 is fixed on the cover plate 2, using existing compressible or deformable materials, and is used to release pressure when the pressure inside the battery is too high to prevent the battery from exploding or leaking; the explosion-proof patch 22 is bonded to the explosion-proof plate 21, and can use existing rupturable or penetrable materials. When the internal pressure of the battery is too high, the explosion-proof patch 22 can be opened to release the pressure and prevent the battery from exploding.

[0037] Furthermore, the positive electrode busbar 8 includes a positive electrode disc body 10; and the top of the positive electrode disc body 10 is formed with six positive electrode protrusion strips 11 arranged around and at equal intervals; and positive electrode through holes 12 penetrating the positive electrode disc body 10 are formed between the positive electrode protrusion strips 11; and the center position of the positive electrode disc body 10 is formed with an annular groove position 13 for being embedded and fixed with the bottom of the battery cell shell 1.

[0038] Specifically, the positive electrode busbar 8 is used to collect the positive current and conduct it to the outside of the battery; the top of the positive electrode disc 10 is formed with six positive electrode protrusions 11 arranged at equal intervals, and these protrusions are used to fix or guide the structure of the internal components of the battery, which can ensure the stability of the position of the components inside the battery and provide good current distribution; positive electrode through holes 12 that penetrate the positive electrode disc 10 are formed between the positive electrode protrusions 11, in order to allow the current and electrolyte to flow inside the positive electrode busbar 8, ensure the uniform distribution and conduction of the positive current, and also reduce the weight of the battery cell; the center position of the positive electrode disc 10 is formed with an annular groove position 13 for fitting and fixing with the bottom of the battery cell shell 1, and this annular groove position 13 is used to ensure the firm connection between the positive electrode busbar 8 and the bottom of the battery cell shell 1, thereby ensuring the position fixation of the internal components of the battery and the reliability of the electrical connection.

[0039] Furthermore, the negative electrode busbar 7 includes a negative electrode disc body 14 ; and three V-shaped negative electrode protrusion strips 15 are formed at intervals at the bottom of the negative electrode disc body 14 ; and a plurality of negative electrode through holes 16 are formed through the top of the negative electrode disc body 14 .

[0040] Specifically, the negative electrode busbar 7 is used to collect the negative electrode current and conduct it to the outside of the battery; three V-shaped negative electrode protrusion bars 15 are formed at intervals on the bottom of the negative electrode disc 14, and these negative electrode protrusion bars 15 are used to support and fix the structure of the internal components of the battery. At the same time, the V-shaped design helps to ensure good contact and connection to ensure the smooth flow of current; a number of negative electrode through holes 16 are formed through the top of the negative electrode disc 14, and these negative electrode through holes 16 are to allow the negative electrode current to flow freely inside the negative electrode busbar 7, thereby ensuring the uniform distribution and conduction of the negative electrode current.

[0041] Furthermore, laser welding is adopted between the negative electrode busbar 7 and the copper nail 17 and the negative electrode sheet 24 of the winding core 9; laser welding is adopted between the positive electrode collector plate and the positive electrode ear of the winding core 9; laser welding is adopted between the cover plate 2 and the top of the battery cell shell 1; and penetration welding is adopted between the positive electrode collector plate and the inner bottom of the battery cell shell 1.

[0042] Specifically, laser welding is used to ensure a stable connection between the two; laser welding and penetration welding can provide high-precision welding, and can ensure good electrical connection and mechanical strength, ensuring the reliability and durability of welding.

[0043] Furthermore, a first separator 25 is provided between the positive electrode sheet 23 and the negative electrode sheet 24 of the winding core 9; and a second separator 26 is provided on the other side of the positive electrode sheet 23 of the winding core 9; and the negative electrode sheet 24, the first separator 25, the positive electrode sheet 23, and the second separator 26 are wound to form the winding core 9.

[0044] Specifically, the first separator 25 is the isolation layer between the positive electrode sheet 23 and the negative electrode sheet 24 in the core 9; the separator can be a polymer material, which is used to prevent the direct flow of electrons between the positive and negative electrodes while allowing ions to move freely inside the battery; the second separator 26 is the isolation layer between the other side of the positive electrode sheet 23 in the core 9 and the negative electrode sheet 24; the second separator 26 helps to enhance the isolation effect between the positive electrode sheet 23 and the negative electrode sheet 24 to reduce the risk of internal short circuit of the battery and improve the safety and stability of the battery; the negative electrode sheet 24, the first separator 25, the positive electrode sheet 23, and the second separator 26 are assembled into the core 9 by winding; this winding structure makes the core 9 occupy a smaller space inside the battery while ensuring the correct arrangement and isolation between the positive and negative electrodes.

[0045] Furthermore, the thickness of the positive busbar 8 is 0.1 to 0.5 mm; the thickness of the negative busbar 7 is 0.1 to 0.5 mm, the diameter of the battery cell housing 1 is 50 to 70 mm, and the height is 80 to 200 mm.

[0046] Specifically, the thickness of the positive busbar 8 and the negative busbar 7 is 0.1 to 0.5 mm, that is, the positive busbar 8 and the negative busbar 7 are both relatively thin components, which are designed to reduce the space occupied inside the battery and provide sufficient structural strength and conductivity; ensuring the matching of the positive busbar 8 and the negative busbar 7 inside the battery while maintaining the consistency of the overall structure.

[0047] Furthermore, the material used for the positive electrode sheet 23 of the winding core 9 is one of lithium iron phosphate, lithium iron manganese phosphate, ternary material, and sodium ion positive electrode material, and the material used for the negative electrode sheet 24 is one of graphite, silicon carbon, and hard carbon.

[0048] Specifically, the material used for the positive electrode sheet 23 is one of lithium iron phosphate, lithium iron manganese phosphate, ternary material, and sodium ion positive electrode material: lithium iron phosphate and lithium iron manganese phosphate belong to phosphate materials, and ternary material usually refers to lithium nickel manganese cobalt or lithium nickel cobalt aluminum; sodium ion positive electrode material refers to the positive electrode material of sodium ion battery; the material used for the negative electrode sheet 24 is one of graphite, silicon carbon, and hard carbon; graphite is a traditional negative electrode material, while silicon-carbon composite material has a higher specific capacity, and the role of hard carbon is to be used in combination with sodium ion positive electrode material.

[0049] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

Claims

1. A cylindrical battery cell structure, comprising a battery cell housing (1), characterized in that: A cover plate (2) is provided on the top of the battery cell shell (1); and a positive pole column (3), a negative pole column (4), a liquid injection port (5), and an explosion-proof valve (6) are provided on the cover plate (2); and the battery cell shell (1) is provided with: a negative busbar (7) located at the inner top of the battery cell shell (1) and electrically connected to the negative pole column (4); a positive busbar (8) located at the inner bottom of the battery cell shell (1); and a winding core (9) located between the negative busbar (7) and the positive busbar (8); a negative electrode sheet (24) of the winding core (9) is electrically connected to the negative busbar (7); and a positive electrode sheet (23) of the winding core (9) is electrically connected to the positive busbar (8) and the positive pole column (3).

2. A cylindrical battery cell structure according to claim 1, characterized in that: The positive electrode busbar (8) comprises a positive electrode disc (10); the top of the positive electrode disc (10) is formed with six positive electrode protrusions (11) arranged at equal intervals around the top; positive electrode through holes (12) penetrating the positive electrode disc (10) are formed between the positive electrode protrusions (11); and the center of the positive electrode disc (10) is formed with an annular groove position (13) for being engaged and fixed with the bottom of the battery cell shell (1).

3. A cylindrical battery cell structure according to claim 1, characterized in that: The negative electrode busbar (7) comprises a negative electrode disc body (14); three V-shaped negative electrode protrusion strips (15) are formed at intervals at the bottom of the negative electrode disc body (14); and a plurality of negative electrode through holes (16) are formed through the top of the negative electrode disc body (14).

4. A cylindrical battery core structure according to claim 1, characterized in that: A copper nail (17) is provided on the cover plate (2), and the negative pole column (4) and the copper nail (17) are electrically connected by laser welding; the positive pole column (3) is formed by stamping the cover plate (2) and is symmetrically arranged with the negative pole column (4).

5. A cylindrical battery cell structure according to claim 4, characterized in that: The outer wall of the copper nail (17) is sleeved with an outer insulating pad (18) and a sealing ring (19); an inner insulating pad (20) is provided below the positive pole (3); and the inner insulating pad (20) and the outer insulating pad (18) separate the positive pole (3) from the negative pole (4).

6. A cylindrical battery cell structure according to claim 1, characterized in that: Laser welding is adopted between the negative electrode collector plate (7) and the copper nail (17) and the negative electrode sheet (24) of the winding core (9); laser welding is adopted between the positive electrode collector plate and the positive electrode ear of the winding core (9); laser welding is adopted between the cover plate (2) and the top of the battery cell shell (1); and penetration welding is adopted between the positive electrode collector plate and the inner bottom of the battery cell shell (1).

7. A cylindrical battery cell structure according to claim 1, characterized in that: The liquid injection port (5) is arranged on the cover plate (2) and is located between the positive pole (3) and the negative pole (4); and the explosion-proof valve (6) comprises an explosion-proof plate (21) fixed to the cover plate (2) and an explosion-proof patch (22) bonded to the explosion-proof plate (21).

8. A cylindrical battery cell structure according to claim 1, characterized in that: A first separator (25) is provided between the positive electrode sheet (23) and the negative electrode sheet (24) of the winding core (9); and a second separator (26) is provided on the other side of the positive electrode sheet (23) of the winding core (9); and the negative electrode sheet (24), the first separator (25), the positive electrode sheet (23), and the second separator (26) are wound to form the winding core (9).

9. A cylindrical battery cell structure according to claim 1, characterized in that: The thickness of the positive electrode busbar (8) is 0.1 to 0.5 mm; the thickness of the negative electrode busbar (7) is 0.1 to 0.5 mm; the diameter of the battery cell shell (1) is 50 to 70 mm, and the height is 80 to 200 mm.

10. The cylindrical battery cell structure according to claim 1, characterized in that: The material used for the positive electrode sheet (23) of the winding core (9) is one of lithium iron phosphate, lithium manganese iron phosphate, ternary material, and sodium ion positive electrode material, and the material used for the negative electrode sheet (24) is one of graphite, silicon carbon, and hard carbon.

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