A lithium power battery with double protection structure

Abstract

The present invention relates to the field of lithium battery technology, and in particular to a lithium-powered battery with a double-protection structure. Its technical solution includes a housing and a battery body installed within the housing. A core shaft is provided within the battery body. A CID element is provided on the top outer ring of the battery body and the core shaft. A safety valve element is installed above the safety valve element. A cap is provided above the CID element. A first insertion hole and a second insertion hole are provided within the core shaft. An insertion cavity is provided within the battery body. A heat dissipation mechanism is installed within the first insertion hole, the second insertion hole, and the insertion cavity. The present invention has a novel and compact structure, protects lithium-powered batteries, improves the safety of lithium battery use, and extends their service life. It assists in dissipating internal heat, reducing battery overheating failures. The external PTC element is easy to replace, making lithium battery maintenance quick and convenient.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium batteries, and in particular to a lithium power battery with a double protection structure. Background Art

[0002] Lithium-ion batteries, due to their high energy, high voltage, wide operating temperature range, and long storage life, have been widely used in small military and civilian appliances, partially replacing traditional batteries. Large-capacity lithium-ion batteries have been trialed in electric vehicles and will become one of the primary power sources for electric vehicles in the 21st century. They will also find applications in satellites, aerospace, and energy storage. The primary function of the CID in lithium-ion batteries is to protect the battery in the event of cell failure. Battery safety issues are primarily caused by thermal runaway. PTC materials have the characteristic that their resistivity increases with temperature. When a high current passes through a PTC device, the Joule heat generated by the PTC causes the temperature to rise, rapidly increasing the component resistance and limiting the current flow, thereby improving the safety of lithium-ion batteries. Traditional batteries eliminate the hidden danger of battery fire caused by runaway by connecting PTCs in series. However, since the PTC overcurrent protection element is generally arranged between the positive pole and the positive cap of the battery, the PTC overcurrent protection element will generate a certain amount of working heat when it is working. Since it is arranged inside the battery, the working heat generated by the PTC overcurrent protection element is focused inside the battery and cannot be dissipated in time, which has a negative impact on the battery performance. The "Cylindrical Battery with External PTC Structure" proposed in patent "CN 206040849 U" arranges the PTC overcurrent protection element on the outside of the cylindrical battery instead of the inside, ensuring that the heat generated by the PTC overcurrent protection element when working can be dissipated in time, thereby improving the safety of the battery. The effectiveness of this solution in dissipating the internal heat of the lithium battery needs to be improved, and if the PTC overcurrent protection component fails, it cannot be easily and promptly replaced, which will affect the timely maintenance and use of the lithium battery. In view of this, we propose a high-safety lithium power battery with a configuration of CID and external PTC, which can fully dissipate the internal heat of the battery, improve the safety of lithium battery use, and have the effect of conveniently replacing the PTC overcurrent protection component. Summary of the Invention

[0003] The purpose of the present invention is to address the problems in the background technology that the heat dissipation effect of the existing external PTC lithium battery needs to be improved, and if the PTC overcurrent protection element fails, it cannot be easily and promptly replaced, which will affect the timely maintenance and use of the lithium battery. A lithium power battery with a dual protection structure is proposed, which is configured with CID and external PTC, can fully dissipate the internal heat of the battery, improve the safety of lithium battery use, and has the effect of convenient replacement of PTC overcurrent protection elements.

[0004] The technical solution of the present invention is as follows: A double-protection structure lithium power battery includes a housing and a battery body installed in the housing, a core shaft is provided inside the battery body, a CID element is provided on the top outer ring of the battery body and the core shaft, a safety valve element is installed above the CID element, and a cap is provided above the safety valve element, a first insertion hole and a second insertion hole are provided in the core shaft, an insertion cavity is provided in the battery body, and a heat dissipation mechanism is installed in the first insertion hole, the second insertion hole, and the insertion cavity;

[0005] The heat dissipation mechanism includes a PTC element, the bottom of which is connected to a connecting column, the bottom end of which is threadedly connected to a connecting disk, the outer ring of which is connected to a plurality of introduction columns along its circumferential array, and a heat dissipation hole is provided in the connecting column and the PTC element, passing through the two.

[0006] Preferably, the PTC element is provided with second heat exhaust holes radially arranged along a circumferential direction of the heat exhaust hole, and a plurality of the second heat exhaust holes are connected to the first heat exhaust hole.

[0007] Preferably, a mounting groove is provided on the top of the cap, a cylindrical hole is provided on the bottom of the mounting groove, and the connecting column passes through the cylindrical hole.

[0008] Preferably, the introduction column is a "7"-shaped rod and is distributed in an array along the outer ring of the connecting disk. The introduction column is adapted to be installed in the second through hole and the through cavity.

[0009] Preferably, a thread groove is provided on the top of the connecting plate, and an outer ring of the bottom end of the connecting column is provided with an external thread corresponding to the thread groove.

[0010] Preferably, a battery positive electrode sheet is provided on the top of the shell, and a battery negative electrode sheet is provided at one end of the bottom of the shell.

[0011] Preferably, the PTC element is adapted to be installed in the inner ring of the mounting groove, and the maximum diameter of the PTC element is smaller than the inner diameter of the mounting groove. The second and first heat exhaust holes are used to guide and discharge the heat in the battery body and the core shaft.

[0012] Preferably, the outside of the battery body is filled with an electrode coating made of PTC material, and the coating is located in the gap between the battery body and the shell.

[0013] Preferably, the introduction column is a PTC material, which is prepared by mixing high-density polyethylene and carbon black.

[0014] Compared with the prior art, the present invention has the following beneficial technical effects:

[0015] 1. The present invention coats the exterior of the battery body with a PTC material and provides a through-hole cavity, a first through-hole, and a second through-hole, through which an introduction column made of the PTC material passes, thereby protecting the battery and extending its service life.

[0016] 2. The present invention provides a detachable PTC element, which makes it easy to replace the PTC element after a failure, thereby improving the convenience of using the lithium battery and improving maintenance efficiency;

[0017] 3. The present invention also provides heat exhaust holes 1 and 2 inside the PTC element and the connecting column to allow heat inside the battery to dissipate, thereby preventing the battery from overheating, extending the battery life, and improving the battery's safety.

[0018] 4. In summary, the present invention has a novel and compact structure, protects lithium-powered batteries, improves the safety of lithium-powered batteries, extends their service life, assists in dissipating internal heat, reduces battery overheating failures, and the external PTC element is easy to replace. The heat generated by the PTC operation does not increase the burden on the battery, making the lithium battery inspection and maintenance convenient and quick. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Provide the overall main schematic diagram of the present invention;

[0020] Figure 2 for Figure 1 Schematic diagram of the structural decomposition;

[0021] Figure 3 It is a schematic diagram of the structural decomposition of the heat dissipation mechanism;

[0022] Figure 4 Give Figure 1 Schematic diagram of the cross-sectional structure;

[0023] Figure 5 for Figure 4 Schematic diagram of the structure of the battery body;

[0024] Figure 6 Schematic diagram of the cross-sectional structure of a PTC component.

[0025] Reference numerals:

[0026] 1. Housing; 11. Battery negative electrode; 12. Battery positive electrode;

[0027] 2. Battery body; 21. Interpenetrating cavity;

[0028] 3. Mandrel; 31. Insertion hole 1; 32. Insertion hole 2;

[0029] 4. CID element;

[0030] 5. Safety valve components;

[0031] 6. Cover cap; 61. Mounting slot;

[0032] 7. Heat dissipation mechanism; 71. PTC element; 72. Connecting column; 73. Connecting plate; 74. Introducing column; 75. Heat dissipation hole 1; 76. Heat dissipation hole 2. DETAILED DESCRIPTION

[0033] The technical solution of the present invention is further described below with reference to the accompanying drawings and specific embodiments.

[0034] Example 1

[0035] like Figure 1-5 As shown, the present invention proposes a double protection structure lithium power battery, including a shell 1 and a battery body 2 installed in the shell 1, the outside of the battery body 2 is filled with an electrode coating made of PTC material, and the coating is located in the gap between the battery body 2 and the shell 1, which is used to isolate the outside of the battery body 2. The surface of the coating is coated with active materials: lithium cobalt oxide active material, PTC coating, and aluminum foil, which can prevent lithium ions from being embedded in the PTC material to destroy the structure of the conductive agent, thereby improving the rate performance and cycle life of the battery; a battery positive electrode sheet 12 is provided on the top of the shell 1, a battery negative electrode sheet 11 is provided at one end of the bottom of the shell 1, and a core shaft 3 is provided inside the battery body 2; as shown Figure 4 As shown, the outer ring of the top of the battery body 2 and the core shaft 3 is provided with a CID element 4, a safety valve element 5 is installed above the CID element 4, and a cap 6 is provided above the safety valve element 5, as shown in FIG. Figure 2 As shown, the top of the cap 6 is provided with a mounting groove 61, and the bottom of the mounting groove 61 is provided with a cylindrical hole; Figure 5 As shown, a first insertion hole 31 and a second insertion hole 32 are formed in the core shaft 3, and an insertion cavity 21 is formed in the battery body 2. A heat dissipation mechanism 7 is installed in the first insertion hole 31, the second insertion hole 32 and the insertion cavity 21. The bottom end of the first insertion hole 31 is connected to one end of the second insertion hole 32, and the other end of the second insertion hole 32 is connected to the top of the insertion cavity 21.

[0036] like Figure 3 and Figure 6 As shown, the heat dissipation mechanism 7 includes a PTC element 71. Figure 2 As shown, the PTC element 71 is adapted to be installed with the inner ring of the mounting groove 61, and the maximum diameter of the PTC element 71 is smaller than the inner diameter of the mounting groove 61, so that the PTC element 71 is installed in the mounting groove 61, and the gap between the outer ring of the PTC element 71 and the mounting groove 61 is used to discharge heat; Figure 3As shown, the bottom of the PTC element 71 is connected to a connecting column 72, which passes through the cylindrical hole at the bottom of the mounting groove 61. The bottom end of the connecting column 72 is threadedly connected to a connecting disk 73. The top of the connecting disk 73 is provided with a threaded groove. The outer ring of the bottom end of the connecting column 72 is provided with an external thread corresponding to the threaded groove, which is used to disassemble and assemble the PTC element 71 relative to the connecting disk 73; the outer ring of the connecting disk 73 is connected to a plurality of introduction columns 74 along its circumferential array. The introduction columns 74 and the connecting disk 73 are both PTC materials, which are made of high-density polyethylene and The carbon black is mixed and prepared, and the introduction column 74 is columnar. The introduction column 74 is a "7"-shaped rod and is distributed in an array along the outer ring of the connecting disk 73. The introduction column 74 is adapted to be installed in the insertion hole 2 32 and the insertion cavity 21. The insertion of multiple introduction columns 74 is arranged in the core shaft 3. The purpose is to allow the introduction column 74 material to participate in electron transmission as a conductive agent under normal conditions; under abuse conditions, when the battery temperature rises and exceeds the melting point of HDPE in the PTC material, the polymer diffuses rapidly, weakening the transmission of the conductive agent conductive channel to protect the battery.

[0037] In this embodiment, the PTC element 71 is protrudingly arranged on the top outside of the shell 1, thereby realizing the design of an external PTC. The heat generated by the setting of the external PTC element 71 during operation can be discharged to the outside of the battery in time, reducing heat generation, thereby extending the overall service life of the lithium battery. The setting of the introduction column 74 protects the battery. At the same time, the introduction column 74 embedded in the battery provides certain support for the safety and stability of the battery. The rotation setting of the PTC element 71 and the connecting disk 73 enables the PTC element 71 to be replaced in time after a fault, and the replacement method is convenient, thereby improving the transportation and use efficiency of the lithium battery.

[0038] Example 2

[0039] like Figure 3 and Figure 6 As shown, based on the first embodiment, a heat dissipation hole 75 is provided within the connecting column 72 and the PTC element 71, extending through both. Heat dissipation holes 76 are radially arranged within the PTC element 71 along the circumference of the first heat dissipation hole 75. Multiple second heat dissipation holes 76 are interlinked with the first heat dissipation hole 75 to receive heat from the battery and dissipate it out of the battery through the first and second heat dissipation holes 75 and 76. Furthermore, in the present invention, if high-voltage heat is generated within the battery during use, this heat is discharged through the second heat dissipation holes 76 and 75.

[0040] The above specific embodiments are only several preferred embodiments of the present invention. Based on the technical solutions of the present invention and the relevant inspirations of the above embodiments, those skilled in the art can make various alternative improvements and combinations to the above specific embodiments.

Claims

1. A lithium power battery with a double protection structure, comprising a housing (1) and a battery body (2) mounted in the housing (1), wherein a core shaft (3) is provided inside the battery body (2), characterized in that: The battery body (2) and the core shaft (3) are provided with a CID element (4) on the top outer ring, a safety valve element (5) is installed above the CID element (4), and a cap (6) is provided above the safety valve element (5). The core shaft (3) is provided with a first insertion hole (31) and a second insertion hole (32), and the battery body (2) is provided with a insertion cavity (21). A heat dissipation mechanism (7) is installed in the first insertion hole (31), the second insertion hole (32) and the insertion cavity (21); The heat dissipation mechanism (7) includes a PTC element (71), the bottom of the PTC element (71) is connected to a connecting column (72), the bottom end of the connecting column (72) is threadedly connected to a connecting disk (73), the outer ring of the connecting disk (73) is connected to a plurality of introduction columns (74) along its circumferential array, the connecting column (72) and the PTC element (71) are provided with a heat exhaust hole (75) that passes through the two, the interior of the PTC element (71) is provided with a heat exhaust hole (76) that is radially arranged along the circumference of the heat exhaust hole (75), and the plurality of heat exhaust holes (76) are connected to the heat exhaust hole (75), the introduction column (74) is a "7"-shaped rod and is distributed along the outer ring array of the connecting disk (73), the introduction column (74) is adapted to be installed in the interpenetrating hole (32) and the interpenetrating cavity (21), and the introduction column (74) is a PTC material, which is prepared by mixing high-density polyethylene and carbon black; The outside of the battery body (2) is filled with an electrode coating made of PTC material, and the coating is located in the gap between the battery body (2) and the shell (1).

2. A double protection structure lithium power battery according to claim 1, characterized in that: The top of the cap (6) is provided with a mounting groove (61), the bottom of the mounting groove (61) is provided with a cylindrical hole, and the connecting column (72) passes through the cylindrical hole.

3. The double protection structure lithium power battery according to claim 1, characterized in that: A thread groove is provided on the top of the connecting plate (73), and an outer ring of the bottom end of the connecting column (72) is provided with an external thread corresponding to the thread groove.

4. The double protection structure lithium power battery according to claim 1, characterized in that: A battery positive electrode sheet (12) is provided on the top of the shell (1), and a battery negative electrode sheet (11) is provided at one end of the bottom of the shell (1).

5. The double protection structure lithium power battery according to claim 2, characterized in that: The PTC element (71) is adapted to be installed in the inner ring of the mounting groove (61), and the maximum diameter of the PTC element (71) is smaller than the inner diameter of the mounting groove (61). The second heat exhaust hole (76) and the first heat exhaust hole (75) are used to guide and discharge heat from the battery body (2) and the core shaft (3).

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