A battery cap structure and lithium battery structure

Abstract

A battery cap structure and a lithium battery structure, wherein the end of a steel shell is welded and fixed to an annular metal ring, and the metal ring can be used as a negative electrode connector to electrically connect the negative terminal of a circuit board to the steel shell; at the same time, the inner end of the metal ring extends toward an explosion-proof valve, and the gap between the inner end of the metal ring and the explosion-proof valve is filled by the inner end of a sealing ring, which is also annular, and its outer end is arranged between the metal ring and the steel shell, so that a seal is formed between the inner wall of the steel shell and the metal ring, and between the metal ring and the explosion-proof valve; in this case, a rubber block formed by plastic filling will be blocked on the side of the metal ring, the sealing ring and the explosion-proof valve facing the circuit board, thereby isolating the rubber block from the electrolyte inside the battery, thereby effectively isolating the rubber block from the electrolyte, thereby preventing the rubber block and the electrolyte from chemically reacting with each other, and also avoiding the working stability and safety problems of the lithium battery caused by this.

Description

Technical Field

[0001] The invention relates to a battery, in particular to a battery cap structure and a lithium battery structure using the battery cap. Background Art

[0002] In the development of modernization, batteries are increasingly widely used in various electrical appliances, and people have higher and higher requirements on battery performance. In order to improve the performance and safety of batteries, the invention patent application with Chinese patent publication number CN112201839A discloses a lithium battery structure, such as Figure 1 As shown, a circuit board 102, a metal ring 103, and an explosion-proof valve 104 are provided on the cap assembly 101 of the battery, and plastic is filled between the inner side of the metal ring and the explosion-proof valve to form a rubber block 105, through which the circuit elements are wrapped. The lithium battery structure can use the through holes to evacuate and inject electrolyte into the winding core in the steel shell, so as to make better use of the battery space and increase the battery capacity. On the other hand, although the rubber block can protect the circuit elements and improve the installation stability and connection strength of each component, its bottom is directly opposite to the winding core 106 of the battery, so that it will contact the electrolyte inside the battery, and the long-term contact between the two is likely to produce a chemical reaction, resulting in corrosion of the rubber block and deterioration of the electrolyte, thereby destroying the safety and stability of the lithium battery. Summary of the invention

[0003] The object of the present invention is to provide a battery cap structure which can prevent a rubber block from contacting an electrolyte inside a battery, and a lithium battery structure using the battery cap, so as to improve the working stability and safety of the lithium battery.

[0004] The battery cap structure described in the present invention comprises an annular and hollow metal ring, a circuit board with a power management function is arranged inside the metal ring, the outer side of the circuit board is connected to an electrode terminal for conducting electricity, and the inner side is provided with an explosion-proof valve; the outer end of the metal ring is covered on the outer edge of the circuit board and is electrically connected with the circuit board circuit, the middle part of the metal ring extends from the outer end located on the inner side of the circuit board, the inner end of the metal ring extends from the middle part of the metal ring to the explosion-proof valve and leaves a gap with the explosion-proof valve; there is also a sealing ring sleeved on the middle part and the inner end of the metal ring, and the inner end of the sealing ring is arranged in the gap between the metal ring and the explosion-proof valve, and a rubber block is filled between the inner side of the circuit board and the metal ring, the sealing ring, and the explosion-proof valve.

[0005] The battery cap structure can be arranged at the positive terminal of the battery, and the electrode terminal is the positive cap serving as the positive electrode connection terminal of the battery; in addition, the battery cap structure can also be arranged at the negative terminal of the battery, and the electrode terminal is the negative electrode connection piece at the bottom of the battery.

[0006] The lithium battery structure described in the present invention includes a steel shell and a winding core arranged in the steel shell, the open end of the steel shell is connected to a ring-shaped and hollow metal ring, a circuit board with a power management function is arranged in the metal ring, the outer side of the circuit board is connected to an electrode terminal for conduction, and the inner side is provided with an explosion-proof valve; the outer end of the metal ring is covered with the outer edge of the circuit board and is electrically connected to the circuit board circuit, the middle part of the metal ring extends to one side of the winding core and leaves a gap with the inner wall of the steel shell, the inner end of the metal ring extends from the middle part of the metal ring to the explosion-proof valve and is spaced a certain distance from each other, a sealing ring is provided on the side of the metal ring facing the winding core, one end of the sealing ring is arranged in the gap between the inner wall of the steel shell and the middle part of the metal ring and the other end is arranged between the inner end of the metal ring and the explosion-proof valve, and a rubber block covering the inner side of the circuit board and the circuit elements thereon is provided in the space surrounded by the circuit board, the metal ring, the sealing ring and the explosion-proof valve.

[0007] The battery cap structure and lithium battery structure described in the present invention assume that the battery cap structure is installed on the positive terminal of the battery, the end of the steel shell is welded and fixed to the annular metal ring, the metal ring can be used as a negative electrode connector to electrically connect the negative terminal of the circuit board to the steel shell, and the steel shell can be used as the negative terminal of the battery to be connected to the electrical equipment; at the same time, the inner end of the metal ring extends toward the explosion-proof valve, and the gap between the inner end of the metal ring and the explosion-proof valve is filled by the inner end of the sealing ring, which is also annular, and its outer end is arranged between the metal ring and the steel shell, so that the inner wall of the steel shell and the metal ring are connected. , the metal ring and the explosion-proof valve are all sealed; in this case, the rubber block formed by plastic filling will be blocked by the metal ring, the sealing ring and the explosion-proof valve on the side facing the circuit board, thereby isolating the rubber block from the electrolyte inside the battery, thereby effectively isolating the rubber block from the electrolyte, thereby preventing the rubber block and the electrolyte from chemically reacting with each other, and avoiding the stability and safety problems of the lithium battery caused by this; in addition, the setting of the metal ring can also be used as a heat dissipation connector to quickly guide the heat generated by the circuit board, electronic components and other parts to the steel shell, thereby improving the heat dissipation efficiency. Similarly, if the battery cap structure is installed at the negative end of the battery, the metal ring will be connected to the steel shell and the positive cap as a positive electrode connector, and the electrode terminal will be used as the negative end of the battery, and this type of battery can also effectively isolate the rubber block from the electrolyte, thereby preventing the rubber block and the electrolyte from chemically reacting with each other, and the cap structure as the negative end of the electrode can reduce the high resistance problem caused by the positive circuit, improve the manufacturing convenience of the battery, and reduce the manufacturing cost and power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a structural schematic diagram of an existing lithium battery structure.

[0009] Figure 2 , 3 It is a structural schematic diagram of the battery cap structure and the lithium battery structure of the present invention.

[0010] Figure 4 It is a structural schematic diagram of a second embodiment of a battery cap structure and a lithium battery structure.

[0011] Figure 5 It is a structural schematic diagram of a battery cap structure and a lithium battery structure embodiment 3.

[0012] Figure 6 It is a structural schematic diagram of a fourth embodiment of a battery cap structure and a lithium battery structure.

[0013] Figure 7 It is a structural schematic diagram of a battery cap structure and a lithium battery structure embodiment 5.

[0014] Figure 8 It is a structural schematic diagram of a sixth embodiment of a battery cap structure and a lithium battery structure.

[0015] Fig. 9 It is a structural schematic diagram of a battery cap structure and a lithium battery structure embodiment 7. DETAILED DESCRIPTION

[0016] Embodiment 1, as Figure 2 , 3 The battery cap structure 10 is disposed at the positive terminal of the lithium battery 20 and is used as the positive electrode of the battery.

[0017] A battery cap structure comprises an annular and hollow metal ring 1, a circuit board 2 with a power management function is arranged inside the metal ring, an electrode terminal 3 for conducting electricity is connected to the outside of the circuit board, and an explosion-proof valve is arranged on the inside; the outer end of the metal ring is covered on the outer edge of the circuit board and is electrically connected to the negative terminal of the circuit board circuit, the middle part of the metal ring extends from the outer end located on the inner side of the circuit board, the inner end of the metal ring extends from the middle part of the metal ring to the explosion-proof valve and leaves a gap with the explosion-proof valve; there is also a sealing ring 5 sleeved on the middle part and the inner end of the metal ring, and the inner end of the sealing ring is arranged in the gap between the metal ring and the explosion-proof valve, and a rubber block 6 is filled between the inner side of the circuit board and the metal ring, the sealing ring and the explosion-proof valve.

[0018] The end of the steel shell is welded and fixed to the annular metal ring, and the metal ring can be used as a negative electrode connector to electrically connect the negative end of the circuit board to the steel shell, and the steel shell can be used as the negative end of the battery to be connected to the electrical equipment; at the same time, the inner end of the metal ring extends toward the explosion-proof valve, and the gap between the inner end of the metal ring and the explosion-proof valve is filled by the inner end of the sealing ring, which is also annular, and its outer end is arranged between the metal ring and the steel shell, so that a seal is formed between the inner wall of the steel shell and the metal ring, and between the metal ring and the explosion-proof valve; in this case, the rubber block formed by plastic filling will be blocked on the side of the metal ring, the sealing ring and the explosion-proof valve facing the circuit board, thereby isolating the rubber block from the electrolyte inside the battery, thereby effectively isolating the rubber block from the electrolyte, thereby preventing the rubber block and the electrolyte from chemically reacting with each other, and avoiding the working stability and safety problems of the lithium battery caused by this; in addition, the setting of the metal ring can also be used as a heat dissipation connector to quickly guide the heat generated by the circuit board, electronic components and other parts to the steel shell, thereby improving the heat dissipation efficiency.

[0019] In the battery cap structure, the outer side of the metal ring 1 is provided with an inwardly recessed annular groove for positioning and connecting with the steel shell of the battery; a clamping block 11 is extended outward from the end of the middle part of the metal ring 1 facing away from the circuit board 2, and the shape of the outer end of the sealing ring 5 matches the shape of the middle part of the metal ring and the clamping block, thereby clamping the outer end of the sealing ring through the interaction between the clamping block and the steel shell, thereby improving the connection strength between the components; in addition, the bottom of the explosion-proof valve extends out to the end of the inner end of the metal ring 1, and the inner end of the metal ring, the bottom extension end of the explosion-proof valve and the inner end of the sealing ring 5, all of which are located in the same radial plane facing the side of the circuit board 2, which is beneficial to the sealing between them and the rubber block and can improve the connection strength of each component.

[0020] In the battery cap structure, the circuit board 2 is provided with a glue hole connecting the inside and outside, and the glue block 6 passes through the circuit board from the outside and extends to the inside of the circuit board to cover the circuit components on the circuit board. This allows the glue to flow from the outside of the circuit board to the inside and eventually form a glue block of the desired shape, thereby ensuring production quality and simplifying the process, while reducing processing costs and improving production efficiency. In addition, the edge of the positive electrode cap adjacent to the circuit board 2 extends outward along the radial direction of the battery, and the outer end of the glue block 6 covers the edge of the positive electrode cap extending outward; after the battery cap structure is installed in the steel shell, plastic is injected to form a glue block, which can not only protect the circuit components on the circuit board and form a seal inside, but also cover the edge of the positive electrode cap to improve its fixing strength and ensure the working stability of the battery.

[0021] In the battery cap structure, the electrode terminal 3 is a positive electrode cap, which is integrally formed and has a plurality of vents 31 communicating with the inner and outer sides, so that the gas ejected during pressure release can be ejected from the vents.

[0022] In the existing lithium battery structure, the tube hole of the explosion-proof metal tube is a smooth straight tube with the same diameter. When the battery is abnormal and the explosion-proof beads are ejected from the explosion-proof metal tube, the explosion-proof beads can easily break through the positive cap and eject out of the battery, thereby endangering the safety of electrical appliances and users. To this end, the battery cap structure described in the present invention, the explosion-proof valve includes an explosion-proof metal tube 41 and an explosion-proof bead 43 arranged in the tube hole 42 of the explosion-proof metal tube; the tube hole includes a large tube hole and a small tube hole arranged in a step shape, the explosion-proof bead is arranged in the small tube hole and sealed against each other, the large tube hole is arranged at one end adjacent to the circuit board 2, and a vent hole 21 is provided on the circuit board relative to the large tube hole, and the diameter of the vent hole is smaller than the explosion-proof bead. The vent hole 21 is an elliptical hole, the size of its short diameter is smaller than the diameter of the explosion-proof bead 43, and the size of its long diameter is larger than the diameter of the explosion-proof bead. As a result, the outside of the circuit board can lead to the inside of the battery through the air holes and the tube holes; under normal use, the explosion-proof bead is fixed at one end of the small tube hole with a smaller diameter to form a seal for the small tube hole; if an abnormality occurs inside the lithium battery or high heat is generated, causing the electrolyte to gasify, a large amount of gas will be filled inside the lithium battery, resulting in an increase in air pressure. The increased air pressure will form a driving force for the explosion-proof bead. When the driving force reaches the set value, the explosion-proof bead is pushed away from the small tube hole and enters the large tube hole, and is blocked by the circuit board and remains in the large tube hole, while the excess gas will be discharged through the large tube hole and the circuit board air hole to form a pressure relief, thereby reducing the air pressure inside the battery, thereby preventing the lithium battery from exploding due to excessive internal air pressure; the air hole is elliptical, which can prevent the explosion-proof bead from spraying out on the one hand, and can also allow gas to be discharged on the other hand, to avoid the explosion-proof bead blocking the air hole and exploding. Therefore, through this structure, the explosion-proof bead can be sprayed out from the small tube hole and stay in the large tube hole, preventing it from spraying out of the battery and endangering the user.

[0023] A lithium battery structure comprises a steel shell 7 and a winding core 8 arranged in the steel shell, wherein an annular and hollow metal ring 1 is connected to the open end of the steel shell, a circuit board 2 with a power management function is arranged in the metal ring, an electrode terminal 3 for conducting electricity is connected to the outside of the circuit board, and an explosion-proof valve is arranged on the inside; the outer end of the metal ring is covered on the outer edge of the circuit board and is electrically connected to the circuit board circuit, the middle part of the metal ring extends to one side of the winding core and a gap is left between the inner wall of the steel shell, the inner end of the metal ring extends from the middle part of the metal ring to the explosion-proof valve and is spaced a certain distance from each other, a sealing ring 5 is arranged on the side of the metal ring facing the winding core, one end of the sealing ring is arranged in the gap between the inner wall of the steel shell and the middle part of the metal ring and the other end is arranged between the inner end of the metal ring and the explosion-proof valve, and a rubber block 6 covering the inner side of the circuit board and the circuit elements thereon is arranged in the space surrounded by the circuit board, the metal ring, the sealing ring and the explosion-proof valve.

[0024] In the lithium battery structure, the outer side of the metal ring 1 is provided with an inwardly recessed annular groove, and the open end of the steel shell 7 is arranged on the annular groove, thereby accurately positioning the metal ring and the steel shell, and then fixing the two to each other by welding.

[0025] In the lithium battery structure, the end of the steel shell is welded and fixed to the annular metal ring, and the metal ring can be used as a negative electrode connector to electrically connect the negative end of the circuit board to the steel shell, and the steel shell can be used as the negative end of the battery to be connected to the electrical equipment; at the same time, the inner end of the metal ring extends toward the explosion-proof valve, and the gap between the inner end of the metal ring and the explosion-proof valve is filled by the inner end of the sealing ring, which is also annular, and its outer end is arranged between the metal ring and the steel shell, so that a seal is formed between the inner wall of the steel shell and the metal ring, and between the metal ring and the explosion-proof valve; in this case, the rubber block formed by plastic filling will be blocked on the side of the metal ring, the sealing ring and the explosion-proof valve facing the circuit board, thereby isolating the rubber block from the electrolyte inside the battery, thereby effectively isolating the rubber block from the electrolyte, thereby preventing the rubber block and the electrolyte from chemically reacting with each other, and avoiding the working stability and safety problems of the lithium battery caused by this.

[0026] Embodiment 2, as Figure 4 shown.

[0027] The battery cap structure and lithium battery structure are as follows: the battery cap structure is arranged at the negative end of the lithium battery structure and is used as the negative electrode of the battery; the electrode terminal 3 is the negative electrode connecting piece at the bottom of the battery; the negative electrode connecting piece is arranged on the outside of the circuit board 2 and is electrically connected to the negative end of the circuit board circuit; the rest is the same as the first embodiment.

[0028] In addition to being installed on the positive electrode of the battery, the battery cap structure can also be installed on the negative electrode of the battery as a connection terminal of the negative electrode of the battery. This can reduce the high resistance problem caused by the positive electrode circuit, improve the manufacturing convenience of the battery, and reduce manufacturing costs and power consumption.

[0029] Embodiment three, as Figure 5 shown.

[0030] In the battery cap structure and lithium battery structure, the electrode terminal 3 is a positive cap, which includes a cap 32 as the positive connection end of the battery and a light-transmitting cover 33 connecting the cap and the circuit board 2. The cap is provided with a vent hole 31, and the light-transmitting cover is provided with a light-transmitting hole 34. In addition, the light-transmitting cover 33 is in the shape of a round cap, and its bottom edge is fixed on the circuit board 2 and connected to the positive output end of the circuit board. There is an arched platform 35 in the middle, and a through hole 36 opposite to the circuit board air vent 21 is provided in the middle of the platform. The cap 32 is connected to the light-transmitting cover platform and blocks the air vent. Therefore, under the premise of ensuring ventilation, an indicator light connected to the circuit board can be installed in the space inside the light-transmitting cover, and the light emits light through the light-transmitting hole, so that the user can intuitively observe the working status of the battery and conveniently understand the battery status.

[0031] Embodiment 4, as Figure 6 shown.

[0032] The battery cap structure and lithium battery structure, the electrode terminal includes a cap 32 as a battery connection end and an inner cover 37 connecting the cap and the circuit board 2, the inner cover is provided with a cover hole 38 opposite to the circuit board air hole 21, and the cap is provided with an air vent 31; the rest is the same as the first embodiment.

[0033] This type of electrode terminal can better release internal pressure and ensure the normal operation of the battery.

[0034] Embodiment 5, as Figure 7 shown.

[0035] The battery cap structure and lithium battery structure are as follows: a conductive ring 44 is connected to the outer wall of the explosion-proof metal tube 41, and the conductive ring is fixedly connected to the inner side of the circuit board 2 and electrically connected; the explosion-proof metal tube 41 is made of nickel material, and the conductive ring 44 is made of copper material; the rest is the same as the first embodiment.

[0036] In order to improve the corrosion resistance of the explosion-proof metal tube and avoid chemical reactions caused by contact with the electrolyte inside the battery, the explosion-proof metal tube is made of nickel material. However, this material is difficult to weld with the PCB used to make the circuit board. Therefore, a conductive ring made of copper material is provided outside the explosion-proof metal tube. Through this conductive ring, the tube can be more stably and firmly connected to the circuit board, thereby ensuring the stability of the battery operation.

[0037] Embodiment six, as Figure 8 shown.

[0038] In the battery cap structure and lithium battery structure, the conductive ring 44 covers the outer end of the explosion-proof metal tube 41 at one end facing the circuit board 2, and an inner buckle 45 is provided at the end of the conductive ring facing away from the circuit board. A buckle groove 46 matching the inner buckle is provided on the outer wall of the explosion-proof metal tube. The conductive ring is fixed to the explosion-proof metal tube by being inserted into the buckle groove through the inner buckle; the rest is the same as the fifth embodiment.

[0039] By positioning the inner buckle and the buckle groove relative to each other, the connection of the conductive end can be effectively ensured, and the convenience and accuracy of installation can be improved.

[0040] Embodiment seven, as Fig. 9 shown.

[0041] A lithium battery structure, a circuit board 2 is connected to a charging connection socket 22, a steel shell 7 is provided with a through hole opposite to the charging connection socket 22, and the socket end of the charging connection socket is arranged on the outer wall of the battery for connecting a charging line to charge the battery.

Claims

1. A battery cap structure, comprising an annular and hollow metal ring (1), wherein a circuit board (2) having a power management function is arranged inside the metal ring, characterized in that: The outer side of the circuit board is connected to an electrode terminal (3) for conducting electricity, and the inner side is provided with an explosion-proof valve; the outer end of the metal ring is covered on the outer edge of the circuit board and is electrically connected to the circuit board circuit, the middle part of the metal ring extends from the outer end located on the inner side of the circuit board, and the inner end of the metal ring extends from the middle part of the metal ring to the explosion-proof valve and leaves a gap between the explosion-proof valve; there is also a sealing ring (5) sleeved on the middle part and the inner end of the metal ring, and the inner end of the sealing ring is arranged in the gap between the metal ring and the explosion-proof valve and seals the gap, the outer end of the sealing ring is sealingly arranged between the metal ring and the steel shell, and a rubber block (6) is filled between the inner side of the circuit board and the metal ring, the sealing ring, and the explosion-proof valve.

2. The battery cap structure according to claim 1, characterized in that: Set at the positive or negative terminal of the lithium battery.

3. The battery cap structure according to claim 1 or 2, characterized in that: An inwardly recessed annular groove is provided on the outer side of the metal ring (1).

4. The battery cap structure according to claim 1 or 2, characterized in that: A clamping block (11) extends outwardly from one end of the middle portion of the metal ring (1) facing away from the circuit board (2), and the shape of the outer end of the sealing ring (5) matches the shape of the middle portion of the metal ring and the clamping block.

5. The battery cap structure according to claim 1 or 2, characterized in that: The bottom of the explosion-proof valve extends toward the end of the inner end of the metal ring (1), and the inner end of the metal ring, the extension end of the bottom of the explosion-proof valve and the inner end of the sealing ring (5) are all located in the same radial plane on the side facing the circuit board (2).

6. The battery cap structure according to claim 1 or 2, characterized in that: The circuit board (2) is provided with a glue hole communicating with the inner and outer sides, and the glue block (6) passes through the circuit board from the outer side and extends to the inner side of the circuit board to cover the circuit components on the circuit board; the edge of the positive electrode cap adjacent to the circuit board (2) extends outwardly in the radial direction of the battery, and the outer end of the glue block (6) covers the edge of the positive electrode cap extending outwardly.

7. The battery cap structure according to claim 1 or 2, characterized in that: The explosion-proof valve comprises an explosion-proof metal tube (41) and an explosion-proof bead (43) arranged in a tube hole (42) of the explosion-proof metal tube; the tube hole comprises a large tube hole and a small tube hole arranged in a step shape, the explosion-proof bead is arranged in the small tube hole and is sealed against each other, the large tube hole is arranged at one end adjacent to the circuit board (2), and an air hole (21) is arranged on the circuit board relative to the large tube hole, and the diameter of the air hole is smaller than that of the explosion-proof bead.

8. The battery cap structure according to claim 6, characterized in that: The air vent (21) is an elliptical hole, the short diameter of which is smaller than the diameter of the explosion-proof bead (43), and the long diameter of which is larger than the diameter of the explosion-proof bead.

9. A lithium battery structure, comprising a steel shell (7) and a winding core (8) disposed in the steel shell, characterized in that: The open end of the steel shell is connected to a metal ring (1), a circuit board (2) is arranged inside the metal ring, a positive electrode cap is connected to the outside of the circuit board and an explosion-proof valve is arranged inside the metal ring; the outer end of the metal ring is covered on the outer edge of the circuit board and is electrically connected to the negative end of the circuit board circuit, the middle of the metal ring extends toward one side of the winding core and a gap is left between the inner wall of the steel shell, the inner end of the metal ring extends from the middle of the metal ring toward the explosion-proof valve and are spaced a certain distance apart from each other, a sealing ring (5) is arranged on the side of the metal ring facing the winding core, the outer end of the sealing ring is sealed in the gap between the inner wall of the steel shell and the middle of the metal ring, and the inner end is sealed between the inner end of the metal ring and the explosion-proof valve, and a rubber block (6) covering the inner side of the circuit board and the circuit elements thereon is arranged in the space surrounded by the circuit board, the metal ring, the sealing ring and the explosion-proof valve.

10. The lithium battery structure according to claim 9, characterized in that: An inwardly recessed annular groove is provided on the outer side of the metal ring (1), and the open end of the steel shell (7) is arranged on the annular groove.

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