Cylindrical lithium battery cap assembly with built-in BMS (Battery Management System) board and lithium battery with cap assembly

Abstract

The utility model relates to the technical field of cylindrical lithium batteries, in particular to a cylindrical lithium battery cap assembly with a built-in BMS (Battery Management System) board and a lithium battery with the cap assembly, which comprise a cap mechanism, and an electrode ring is arranged in the cap mechanism; the cover cap mechanism comprises a cover cap shell, an electrode conductive metal cover, a BMS main board part and a plastic explosion-proof support used for protecting electronic elements at the bottom of the BMS main board part. According to the cylindrical lithium battery cap assembly with the built-in BMS board and the lithium battery with the cap assembly, provided by the utility model, large-scale production is facilitated, and the production efficiency can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of cylindrical lithium batteries, in particular to a cylindrical lithium battery cap assembly with a built-in BMS board and a lithium battery with the cap assembly. Background Art

[0002] Cylindrical lithium battery is a common secondary battery, also called lithium-ion battery. It consists of a cylindrical container, which contains components such as positive electrode, negative electrode and electrolyte. The battery cap is the component structure of the cylindrical lithium battery, which performs the sealing process on the top.

[0003] The applicant has applied for an invention patent with application number CN202310996046.2 and the name of "A cylindrical lithium battery cap with built-in BMS board", which includes: a steel shell; a cap with a BMS board connected to the inner side of the steel shell; a plastic explosion-proof bracket, the lower end of which is connected to the inside of the cap with the BMS board; an electrode conductive metal cover, the lower end of which is connected to the inside of the plastic explosion-proof bracket; a PCBA board, connected to the outer edge of the upper end of the electrode conductive metal cover; the middle of the lower end of the PCBA board It extends into the middle of the electrode conductive metal cover, and the PCBA board includes a BMS chip, a power management chip, a battery control chip, a display chip, and a multi-way protector; the upper outer edge of the PCBA board is connected to a negative electrode hardware ring; the opening of the steel shell is rolled inward in a whole circle and contacts the negative electrode hardware ring to conduct the negative electrode; the inner side wall of the negative electrode hardware ring is connected to the positive electrode plastic cover, there is damping between the two, and the middle part of the positive electrode plastic cover is an open hole structure, and it fits with the external positive electrode hardware column. The present invention solves the cap structure of the existing cylindrical lithium battery. In order to meet the use requirements, the BMS used for monitoring is built-in to simplify the installation steps.

[0004] In the above scheme, the negative electrode hardware ring is welded to the opening of the steel shell by soldering. However, since the opening of the steel shell is in an inwardly rolled state, it is difficult to perform manual welding. In addition, sufficient time is required during the welding process to ensure that the solder is fully melted and wets the object to be welded. Therefore, it takes a lot of time and is not conducive to large-scale production. Utility Model Content

[0005] In order to solve the problems in the above-mentioned background technology, the utility model provides a cylindrical lithium battery cap assembly with a built-in BMS board and a lithium battery with the cap assembly, which is convenient for large-scale production and can improve production efficiency.

[0006] The utility model solves the technical problem by adopting the following scheme: a cylindrical lithium battery cap assembly with a built-in BMS board, comprising a cap mechanism, wherein an electrode ring is arranged inside the cap mechanism;

[0007] The capping mechanism includes a capping shell, an electrode conductive metal cover, a BMS mainboard, and a plastic explosion-proof bracket for protecting electronic components at the bottom of the BMS mainboard;

[0008] The cap housing is used to be connected to the inner side of the steel shell of the cylindrical lithium battery;

[0009] The electrode conductive metal cover is located inside the cap housing and is used to be electrically connected to the battery cell of the lithium battery;

[0010] The plastic explosion-proof bracket is located inside the electrode conductive metal cover;

[0011] The BMS mainboard is located at the top of the plastic explosion-proof bracket;

[0012] The electrode ring is located at the top of the BMS main board. The cap shell is connected to the electrode ring, the electrode conductive metal cover, and the BMS main board through an injection molding process to form a whole and form a through hole. The electrode ring is embedded in the bottom of the cap shell and exposed to the outer surface of the cap shell through the through hole. The electrode ring is electrically connected to the steel shell.

[0013] Furthermore, the electrode ring includes an electrode ring and a protrusion arranged on the outside of the electrode ring; a plurality of protrusions are provided and are evenly arranged on the outside of the electrode ring; the electrode ring is tightly attached to the bottom surface of the cap shell, and the protrusion is tightly attached to the through hole and tightly fits with the steel shell.

[0014] Furthermore, the protrusion includes a transverse portion and a vertical portion, the transverse portion is tightly attached to the top surface of the electrode ring, the vertical portion is tightly attached to the outer wall of the electrode ring, the top surface of the transverse portion and the side surface of the vertical portion are both exposed to the outer surface of the cap shell, the top surface of the transverse portion is flush with the top surface of the cap shell, and the side surface of the vertical portion is flush with the outer side surface of the cap shell.

[0015] In summary, the beneficial effects of the utility model are:

[0016] The cap housing is connected to the electrode ring, the electrode conductive metal cover, and the BMS main board through an injection molding process to form a whole. Through the above settings, the cap assembly has excellent sealing and a stable connection structure, which can prevent water from entering the cap assembly to damage the electronic components, and also prevent leakage inside the battery;

[0017] The steel shell and the electrode ring can be electrically connected by extrusion contact, thereby achieving rapid and large-scale production;

[0018] There are several bumps evenly arranged outside the electrode ring. By setting multiple bumps, the contact area between the electrode ring and the steel shell is increased, the internal resistance of the battery is reduced, the conductivity of the battery is improved, and the battery is charged and discharged more quickly and efficiently.

[0019] The convex block includes a transverse portion and a vertical portion, and the top surface and the side surface of the convex block are exposed to the outer surface of the cap shell. Through the above arrangement, the contact area between the electrode ring and the steel shell is further increased, and the current transmission efficiency is improved;

[0020] The electrode conductive metal cover is used to connect cylindrical lithium battery cells. Laser welding can be used to achieve electrical connection between the electrode conductive metal cover and the battery cell, further improving production efficiency.

[0021] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following preferred embodiments are specifically cited and described in detail with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a cross-sectional view of the lithium battery of this embodiment;

[0023] Figure 2 is a schematic structural diagram of the cap assembly of this embodiment;

[0024] Figure 3 This is a connection diagram between the electrode ring and the cap shell of this embodiment.

[0025] In the figure: 1. capping mechanism; 11. capping shell; 12. electrode conductive metal cover; 13. BMS main board; 14. plastic explosion-proof bracket; 2. steel shell; 3. electrode ring. DETAILED DESCRIPTION

[0026] In order to make the content of the utility model more clearly understood, the utility model is further described below based on specific embodiments in combination with the accompanying drawings.

[0027] It should be noted that the terms "center", "upper", "lower", "front", "back", "left", "right", "inner", "outer" and the like used herein to indicate directions or positional relationships are based on directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. Unless otherwise specified, "plurality" means two or more.

[0028] Unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this utility model can be understood by specific circumstances.

[0029] like Figures 1 to 3 As shown, this embodiment is a cylindrical lithium battery cap assembly with a built-in BMS board and a lithium battery with the cap assembly, including a cap mechanism 1, in which an electrode ring 3 is arranged; the cap mechanism 1 is composed of a cap shell 11, an electrode conductive metal cover 12, a BMS main board part 13, and a plastic explosion-proof bracket 14 for protecting the electronic components at the bottom of the BMS main board part 13.

[0030] The electrode ring of this embodiment is a negative electrode ring, and the electrode conductive metal cover is a positive electrode conductive metal cover.

[0031] The cap housing 11 of this embodiment is used to connect to the inner side of the steel shell 2 of the cylindrical lithium battery; the electrode conductive metal cover 12 is located in the cap housing 11 and is used to be electrically connected to the positive electrode of the lithium battery. The plastic explosion-proof bracket 14 is located in the electrode conductive metal cover 12 and is used to protect the electronic components at the bottom of the BMS main board 13 to prevent the risk of explosion caused by battery failure.

[0032] The BMS main board 13 is located at the top of the plastic explosion-proof bracket 14; the electrode ring 3 is located at the top of the BMS main board 13. The electrode ring 3, the electrode conductive metal cover 12, and the BMS main board 13 are assembled and placed in the plastic mold of the cap shell 11, and then the cap shell 11 is formed by injection molding, and a through hole is formed on the cap shell to expose the electrode ring 3. The electrode ring 13 is embedded in the bottom of the cap shell 11 and a part of it is exposed on the outer surface of the cap shell 11. The electrode ring 3 is electrically connected to the steel shell 2. Through the above arrangement, the cap shell 11, the electrode ring 3, the electrode conductive metal cover 12, and the BMS main board 13 are connected as a whole, and have excellent sealing and a stable connection structure, which can prevent water from entering the interior of the cap assembly to damage electronic components, and also prevent leakage from the battery.

[0033] The battery management system of this embodiment is integrated inside the battery cap, which improves the safety of battery use and optimizes the battery structure.

[0034] like Figure 3As shown, the electrode ring 3 of this embodiment includes an electrode ring and a protrusion arranged on the outside of the electrode ring; during the production process of the cap assembly of this embodiment, the electrode ring 3 is electrically connected to the steel shell 2 through extrusion contact, which is convenient for large-scale production and improves production efficiency.

[0035] The electrode ring 3 of this embodiment is provided with six protrusions, which are evenly arranged on the outside of the electrode ring. Through the above arrangement, the contact area between the electrode ring 3 and the steel shell 2 is increased, the resistance between the connectors is reduced, and the power-on performance of the battery is greatly improved. The electrode ring of this embodiment is clamped at the bottom of the cap shell 11, and is closely attached to the bottom surface of the cap shell 11. The protrusion is closely attached to the through hole and is flush with the outer surface of the cap shell 11 and forms an electrical connection with the steel shell 2.

[0036] The cap shell 11 of the present embodiment is formed by injection molding of polypropylene material, which has high stability and corrosion resistance, can protect the components inside the cap, and improve the safety of battery use.

[0037] like Figure 2 As shown, the bump is in a G-shape and is closely attached to the outside of the electrode ring, and the top and side surfaces of the bump are exposed on the outer surface of the cap shell 11. The top surface of the bump is flush with the top surface of the cap shell 11, and the side surface of the bump is flush with the side surface of the cap shell 11. The good mechanical fit between the bump and the cap shell 11 improves the sealing and protection performance of the overall assembly, preventing water from entering the BMS board while also preventing leakage from the bottom.

[0038] like Figure 1 As shown, the positive electrode of the cylindrical lithium battery of this embodiment is located at the bottom of the electrode conductive metal cover 12 and is electrically connected to the electrode conductive metal cover 12. The positive electrode of the battery cell and the electrode conductive metal cover 12 can be electrically connected by laser welding, further improving the battery production efficiency.

[0039] The embodiments described above are only preferred implementation modes of the present utility model and cannot be used to limit the protection scope of the present utility model. Any non-substantial changes and modifications made by technicians in this field on the basis of the utility model shall fall within the protection scope of the present utility model.

Claims

1. A cylindrical lithium battery cap assembly with a built-in BMS board, comprising a capping mechanism (1), characterized in that: An electrode ring (3) is provided inside the capping mechanism (1); The capping mechanism (1) comprises a capping shell (11), an electrode conductive metal cover (12), a BMS mainboard (13), and a plastic explosion-proof bracket (14) for protecting electronic components at the bottom of the BMS mainboard (13); The cap housing (11) is used to be connected to the inner side of the steel shell (2) of the cylindrical lithium battery; The electrode conductive metal cover (12) is located inside the cap housing (11) and is used to be electrically connected to the battery cell of the lithium battery; The plastic explosion-proof bracket (14) is located inside the electrode conductive metal cover (12); The BMS mainboard (13) is located at the top of the plastic explosion-proof bracket (14); The electrode ring (3) is located at the top of the BMS mainboard (13); the cap shell (11) is provided with a through hole; the electrode ring (3) is embedded in the bottom of the cap shell (11) and is exposed on the outer surface of the cap shell (11) through the through hole; the electrode ring (3) is electrically connected to the steel shell (2).

2. A cylindrical lithium battery cap assembly with a built-in BMS board according to claim 1, characterized in that: The electrode ring (3) comprises an electrode ring and a protrusion arranged outside the electrode ring; a plurality of protrusions are provided and are evenly arranged outside the electrode ring; the electrode ring is tightly attached to the bottom surface of the cap shell (11), and the protrusion is tightly attached to the through hole and is tightly fitted to the steel shell (2).

3. A cylindrical lithium battery cap assembly with built-in BMS board according to claim 2, characterized in that: The protrusion comprises a transverse portion and a vertical portion, the transverse portion is tightly attached to the top surface of the electrode ring, and the vertical portion is tightly attached to the outer wall of the electrode ring. The top surface of the transverse portion and the side surface of the vertical portion are both exposed to the outer surface of the cap shell (11), the top surface of the transverse portion is flush with the top surface of the cap shell (11), and the side surface of the vertical portion is flush with the outer side surface of the cap shell (11).

4. A lithium battery, characterized in that: The invention comprises the cap assembly described in any one of claims 1 to 3.

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