A high energy density cylindrical battery and its manufacturing method

Abstract

The present invention discloses a high-energy-density cylindrical battery and a manufacturing method thereof. The high-energy-density cylindrical battery includes a battery steel shell, a battery core is disposed inside the battery steel shell, a negative electrode cover assembly is disposed at the bottom of the battery steel shell, a positive electrode cover assembly is disposed at the top of the battery steel shell, the positive electrode cover assembly includes a positive electrode post, the positive electrode post is disposed at the top of the battery steel shell, a sealing assembly is disposed between the positive electrode post and the battery steel shell, a positive electrode connecting piece is connected between the positive electrode post and the battery core, and the positive electrode post is provided with a through hole. The through hole is provided on the positive electrode post of the present invention, which facilitates welding equipment to weld the positive electrode connecting piece and the positive electrode post from above the positive electrode post, eliminating the need to bend and fold the positive electrode connecting piece multiple times and welding from the inside of the battery, saving internal battery space. In this way, the energy density of the battery can be easily improved under the same spatial dimensions.

Description

Technical Field

[0001] The present invention relates to the technical field of battery manufacturing, and in particular to a high-energy-density cylindrical battery and a manufacturing method thereof. Background Art

[0002] A battery is a power supply device, and there are many types of batteries. Depending on the application scenario and situation, the battery will also have different shapes. Cylindrical batteries are one of them. Generally, cylindrical batteries are composed of several parts such as poles (positive and negative poles), cells, and shells, and electrode connectors are connected between the poles and cells.

[0003] like Figure 7 The existing cylindrical battery has the following disadvantages: when the electrode connecting piece in the existing cylindrical battery is connected to the pole, the connecting piece and the pole need to be welded together from the bottom of the pole to form a passage. In this connection method, the connecting piece needs to be bent and folded multiple times inside the battery, occupying the internal space of the battery (when the height of the aluminum shell is constant) and losing corresponding energy. Summary of the Invention

[0004] In order to overcome the above technical problems, the object of the present invention is to provide a high energy density cylindrical battery and a manufacturing method thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A high-energy-density cylindrical battery comprises a battery steel shell, a battery core is arranged inside the battery steel shell, a negative electrode cover assembly is arranged at the bottom of the battery steel shell, a positive electrode cover assembly is arranged at the top of the battery steel shell, the positive electrode cover assembly includes a positive electrode column, the positive electrode column is arranged at the top of the battery steel shell, a sealing assembly is arranged between the positive electrode column and the battery steel shell, a positive electrode connecting piece is connected between the positive electrode column and the battery core, a through hole is provided on the positive electrode column, and a pressure plate is provided at the top port of the through hole.

[0007] As a further solution of the present invention: the top port of the through hole is provided with an annular supporting step, and the top port of the through hole is connected to the pressure plate through the annular supporting step.

[0008] As a further solution of the present invention: the sealing assembly includes a positive electrode stopping ring frame, which is cooperated with and sleeved on the bottom of the positive electrode column, and the top of the battery steel shell is provided with a shrinking ring that fits on the upper side of the positive electrode stopping ring frame, a positive electrode sealing ring is provided between the positive electrode stopping ring frame and the positive electrode column, the top of the positive electrode column is sleeved with a positive electrode insulating gasket located on the upper side of the shrinking ring, and the top edge of the positive electrode column is provided with a limiting convex ring.

[0009] As a further solution of the present invention: an annular interlocking groove is provided on the positive electrode insulating gasket, an annular steel sheet is interlocked in the annular interlocking groove, and the annular steel sheet is located at the lower side of the limiting convex ring.

[0010] As a further solution of the present invention: the negative electrode cover plate assembly includes a negative electrode substrate, which is arranged on the inner side of the bottom of the battery steel shell, a negative electrode connecting piece is connected between the negative electrode substrate and the battery core, and a negative electrode sealing ring is arranged between the negative electrode substrate and the battery steel shell.

[0011] As a further solution of the present invention: an annular groove is provided on the inner ring side wall of the negative electrode sealing ring, and the edge of the negative electrode substrate is embedded in the annular groove.

[0012] As a further solution of the present invention: the battery steel shell is provided with an annular bending structure near the bottom, the annular bending structure is affixed to the upper side of the negative electrode sealing ring, and the bottom edge of the battery steel shell is provided with a bending edge affixed to the bottom of the negative electrode sealing ring.

[0013] A method for manufacturing a high energy density cylindrical battery, the specific steps are as follows:

[0014] The first step is to manufacture a positive electrode column with a through hole and a matching pressing plate;

[0015] The second step is to rivet the positive electrode cover assembly and the battery steel shell at one time to complete the fixed assembly;

[0016] Step 3: Weld the positive electrode connector to the battery core;

[0017] Step 4: Weld the positive electrode connecting piece and the positive electrode post from above the positive electrode post and through the through-hole position;

[0018] Step 5: Assemble the negative electrode cover assembly on the bottom of the battery steel casing;

[0019] Step 6. Connect the pressure plate assembly to the port of the through hole.

[0020] Beneficial effects of the present invention:

[0021] 1. The positive electrode column of the present invention is provided with a through hole, which facilitates welding equipment to weld the positive electrode connecting piece and the positive electrode column from above the positive electrode column. There is no need to bend and fold the positive electrode connecting piece multiple times. Welding is done from the inside of the battery, saving internal space of the battery. In this way, the energy density of the battery can be increased with the same space size.

[0022] 2. The positive electrode cover plate assembly of the present invention is processed by a shrinking riveting process and can be assembled and fixed on the battery steel shell as a whole, avoiding multiple riveting or welding processes that increase the probability of component damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below with reference to the accompanying drawings.

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0025] Figure 2 This is a schematic diagram of the three-dimensional structure of the positive electrode column and the battery core in the present invention;

[0026] Figure 3 This is a schematic diagram of the three-dimensional structure of the negative electrode connecting piece and the battery core in the present invention;

[0027] Figure 4 It is a schematic diagram of the overall cross-sectional structure of the present invention;

[0028] Figure 5 yes Figure 4 Schematic diagram of the enlarged structure at A in the middle;

[0029] Figure 6 yes Figure 4 Schematic diagram of the enlarged structure at B in the middle;

[0030] Figure 7 It is a schematic diagram of the structure of an existing cylindrical battery.

[0031] In the figure: 1. Battery steel shell; 2. Positive cover assembly; 3. Negative cover assembly; 4. Positive pole; 5. Positive connecting piece; 6. Battery core; 7. Negative connecting piece; 8. Annular support step; 9. Press plate; 10. Annular steel sheet; 11. Positive insulating gasket; 12. Annular fitting groove; 13. Through hole; 14. Positive sealing ring; 15. Positive stop ring frame; 16. Negative sealing ring; 17. Annular slot; 18. Negative substrate; 19. Annular bending structure; 20. Positive pole; 21. Electrode connecting piece; 22. Cover member; 23. Battery shell; 24. Negative assembly; 25. Shrinking ring; 26. Limiting convex ring. DETAILED DESCRIPTION

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0033] like Figure 7As shown, the existing cylindrical battery includes a battery housing 23, the bottom of the battery housing 23 is equipped with a negative electrode assembly 24, the top of the battery housing 23 is connected to a cover member 22, the cover member 22 is provided with a positive electrode column 20, and the bottom of the positive electrode column 20 is matched with an electrode connecting piece 21.

[0034] The existing cylindrical battery manufacturing method has the following specific steps:

[0035] First, weld one end of the electrode connecting piece 21 to one end of the battery cell, and bend the electrode connecting piece 21 so that there is a certain space between the other end and the battery cell to facilitate subsequent welding operations. Then, use welding equipment to weld the other end of the electrode connecting piece 21 to the positive electrode column 20 from below the positive electrode column 20; then assemble the cover plate 22 to the top of the battery shell 23, and weld the cover plate 22 to the battery shell 23; finally, connect the negative electrode assembly 24 to the bottom of the battery shell 23.

[0036] like Figures 1-6 As shown, a high energy density cylindrical battery comprises a battery steel shell 1, a battery core 6 is assembled inside the battery steel shell 1, a negative cover assembly 3 is provided at the bottom of the battery steel shell 1, and the negative cover assembly 3 comprises a negative substrate 18, the negative substrate 18 is provided on the inner side of the bottom of the battery steel shell 1, a negative connecting piece 7 is welded between the negative substrate 18 and the battery core 6, a negative sealing ring 16 is provided between the negative substrate 18 and the battery steel shell 1, and an annular groove 17 is provided on the inner ring side wall of the negative sealing ring 16 The edge of the negative electrode substrate 18 is embedded in the annular groove 17, so that the negative electrode sealing ring 16 and the negative electrode substrate 18 are assembled and connected together. The battery steel shell 1 is provided with an annular bending structure 19 near the bottom. The annular bending structure 19 is attached to the upper side of the negative electrode sealing ring 16. The bottom edge of the battery steel shell 1 is provided with a bent edge attached to the bottom of the negative electrode sealing ring 16. The annular bending structure 19 and the bent edge are used to limit the negative electrode sealing ring 16, so that it is firmly in the corresponding position and enhances the sealing effect.

[0037] A positive electrode cover assembly 2 is provided on the top of the battery steel shell 1. The positive electrode cover assembly 2 includes a positive electrode column 4. The positive electrode column 4 is provided on the top of the battery steel shell 1. A sealing assembly is provided between the positive electrode column 4 and the battery steel shell 1. The sealing assembly includes a positive electrode stop ring frame 15. The positive electrode stop ring frame 15 is fitted on the bottom of the positive electrode column 4, and the positive electrode stop ring frame 15 is inside the battery steel shell 1. A shrinking ring 25 is provided on the top of the battery steel shell 1, which is attached to the upper side of the positive electrode stop ring frame 15. The shrinking ring 25 is obtained by a shrinking process. A positive electrode sealing ring 14 is provided between the positive electrode stop ring frame 15 and the positive electrode column 4. The outer ring side wall of the positive electrode sealing ring 14 is tightly attached to the positive electrode stop ring On the inner ring side wall of the annular frame 15, the inner ring side wall of the positive sealing ring 14 is tightly attached to the outer wall of the positive electrode column 4 to achieve a sealing effect. The top of the positive electrode column 4 is sleeved with a positive insulating gasket 11 on the upper side of the shrinking ring 25. An annular fitting groove 12 is provided at the inner ring position of the top end surface of the positive insulating gasket 11. An annular steel sheet 10 is fitted in the annular fitting groove 12. A limiting convex ring 26 is provided on the upper side of the annular steel sheet 10 on the top edge of the positive electrode column 4. The limiting convex ring 26 is formed by a riveting process after the positive stop annular frame 15, the positive sealing ring 14, the positive insulating gasket 11 and the annular steel sheet 10 are assembled, so as to facilitate the limiting of the installed components so as to facilitate the combination and connection together.

[0038] A positive electrode connecting piece 5 is welded between the bottom of the positive electrode column 4 and the top of the battery core 6. A through hole 13 is provided in the middle of the positive electrode column 4. The through hole 13 facilitates the laser welding equipment to weld the positive electrode connecting piece 5 and the positive electrode column 4 from above the positive electrode column 4. There is no need for too much working space between the battery core 6 and the positive electrode column 4, that is, there is no need for the positive electrode connecting piece 5 to bend and fold to occupy too much space inside the battery; an annular support step 8 is provided at the top port of the through hole 13, and a pressure plate 9 is provided at the top port of the through hole 13 through the annular support step 8. The pressure plate 9 is welded together with the positive electrode column 4 to form a complete positive cover assembly 2.

[0039] A method for manufacturing a high energy density cylindrical battery, the specific steps are as follows:

[0040] The first step is to process a through hole 13 at the center of the positive electrode column 4, and produce a pressure plate 9 according to the size of the upper end of the through hole 13;

[0041] The second step is to assemble the positive electrode sealing ring 14, the positive electrode stop ring frame 15, the positive electrode insulating gasket 11 and the annular steel sheet 10 in the positive electrode cover assembly 2 onto the positive electrode column 4 in sequence, and then perform a shrinking riveting process to obtain a shrinking ring 25 and a limiting convex ring 26, that is, the shrinking ring 25 and the battery steel shell 1 are an integrated structure, and the limiting convex ring 26 and the positive electrode column 4 are an integrated structure, so that the positive electrode cover assembly 2 and the battery steel shell 1 are assembled and fixed as a whole;

[0042] Step 3: Weld the positive electrode connector 5 to one end of the battery core 6, and then introduce them into the battery steel shell 1;

[0043] Step 4: Weld the positive electrode connecting piece 5 and the positive electrode post 4 through the through hole 13 from above the positive electrode post 4, i.e., outside the battery;

[0044] Step 5: Weld the negative electrode connecting piece 7 between the other end of the battery cell 6 and the negative electrode substrate 18, and assemble the negative electrode sealing ring 16 to the edge of the negative electrode substrate 18. Then, fold the negative electrode connecting piece 7 and connect it to the negative electrode substrate 18 and insert it into the bottom inner side of the battery steel casing 1. Bend the corresponding position of the bottom of the battery steel casing 1 to form an annular bending structure 19 and a bending edge to constrain the negative electrode substrate 18 and enhance the sealing performance.

[0045] Step 6: Assemble the pressing plate 9 at the end of the through hole 13 and weld it to the positive electrode column 4 to ensure that the connection position is sealed. The overall assembly of the battery is completed.

[0046] The positive electrode sealing ring 14, positive electrode stopping ring frame 15, positive electrode column 4, positive electrode insulating gasket 11 and annular steel sheet 10 in the positive electrode cover plate assembly 2 of the present invention are assembled and fixedly connected by shrinking riveting at one time. At the same time, a through hole 13 is opened on the positive electrode column 4 to facilitate the laser welding equipment to weld the positive electrode connecting piece 5 and the positive electrode column 4 from above the positive electrode column 4.

[0047] After the positive electrode connecting piece 5 is welded and assembled at the through hole 13 opened on the positive electrode column 4, the data obtained through conventional testing are as follows:

[0048]

[0049] The above is a detailed description of an embodiment of the present invention. However, the content described is only a preferred embodiment of the present invention and should not be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A high energy density cylindrical battery, comprising a battery steel shell (1), a battery core (6) disposed inside the battery steel shell (1), a negative electrode cover assembly (3) disposed at the bottom of the battery steel shell (1), and a positive electrode cover assembly (2) disposed at the top of the battery steel shell (1), characterized in that: The positive electrode cover plate assembly (2) includes a positive electrode column (4), the positive electrode column (4) is arranged on the top of the battery steel shell (1), a sealing assembly is provided between the positive electrode column (4) and the battery steel shell (1), a positive electrode connecting piece (5) is connected between the positive electrode column (4) and the battery core (6), a through hole (13) is provided on the positive electrode column (4), and a pressure plate (9) is provided at the top end of the through hole (13); The top port of the through hole (13) is provided with an annular support step (8), and the top port of the through hole (13) is connected to the pressure plate (9) through the annular support step (8); The sealing assembly includes a positive electrode stop ring frame (15), the positive electrode stop ring frame (15) is fitted on the bottom of the positive electrode column (4), the top of the battery steel shell (1) is provided with a shrinking ring (25) attached to the upper side of the positive electrode stop ring frame (15), a positive electrode sealing ring (14) is provided between the positive electrode stop ring frame (15) and the positive electrode column (4), the top of the positive electrode column (4) is provided with a positive electrode insulating gasket (11) on the upper side of the shrinking ring (25), and the top edge of the positive electrode column (4) is provided with a limiting convex ring (26).

2. A high energy density cylindrical battery according to claim 1, characterized in that: An annular interlocking groove (12) is provided on the positive electrode insulating gasket (11), an annular steel sheet (10) is interlocked in the annular interlocking groove (12), and the annular steel sheet (10) is located on the lower side of the limiting convex ring (26).

3. A high energy density cylindrical battery according to claim 1, characterized in that: The negative electrode cover plate assembly (3) includes a negative electrode substrate (18), the negative electrode substrate (18) is arranged on the inner side of the bottom of the battery steel shell (1), a negative electrode connecting piece (7) is connected between the negative electrode substrate (18) and the battery core (6), and a negative electrode sealing ring (16) is arranged between the negative electrode substrate (18) and the battery steel shell (1).

4. A high energy density cylindrical battery according to claim 3, characterized in that: An annular groove (17) is provided on the inner ring side wall of the negative electrode sealing ring (16), and the edge of the negative electrode substrate (18) is embedded in the annular groove (17).

5. A high energy density cylindrical battery according to claim 4, characterized in that: The battery steel housing (1) is provided with an annular bending structure (19) near the bottom, and the annular bending structure (19) is attached to the upper side of the negative electrode sealing ring (16). The bottom edge of the battery steel housing (1) is provided with a bending edge attached to the bottom of the negative electrode sealing ring (16).

6. A method for manufacturing a high energy density cylindrical battery, for manufacturing the high energy density cylindrical battery according to claim 1, characterized in that: The specific steps are as follows: The first step is to manufacture a positive electrode column (4) with a through hole (13) and a matching pressing plate (9); Step 2: Rivet the positive electrode cover assembly (2) and the battery steel shell (1) at one time to complete the fixed assembly; Step 3: Welding the positive electrode connecting piece (5) and the battery core (6); Step 4: Welding the positive electrode connecting piece (5) and the positive electrode post (4) from above the positive electrode post (4) and through the through hole (13); Step 5: Assemble the negative electrode cover assembly (3) on the bottom of the battery steel housing (1); Step 6: Assemble and connect the pressing plate (9) to the end of the through hole (13).

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