Lithium battery module with fire extinguishing and self-protection functions

Abstract

The utility model discloses a lithium battery module with a fire extinguishing self-protection function, and belongs to the technical field of modular batteries. The lithium battery module with the fire extinguishing and self-protection functions comprises a battery cell support, lithium battery cells are installed in the battery cell support, the battery cell support comprises a plurality of fire extinguishing units made of plastic, the four fire extinguishing units define a second battery jar used for wrapping the lithium battery cells, the lithium battery cells and the fire extinguishing units are arranged in a staggered mode, and the fire extinguishing units are arranged in the second battery jar. The fire extinguishing unit comprises a shell, an alkaline agent cavity is formed in the shell, and the alkaline agent cavity is filled with sodium bicarbonate powder; the battery module has the advantages that the battery cells in the battery module can be conveniently protected, and the fire extinguishing reaction time is short and the speed is high.

Description

Technical Field

[0001] The utility model relates to the technical field of modular batteries, in particular to a lithium battery module with fire extinguishing and self-protection functions. Background Art

[0002] Lithium batteries are energy storage batteries that use metallic lithium or lithium ions as positive and negative electrodes. They are widely used because of their high power storage capacity, long service life, light weight, and green and pollution-free nature. However, there are safety hazards such as fire and spontaneous combustion when using such batteries.

[0003] In order to solve the above problems, the utility model patent with announcement number CN219979735U provides a lithium battery module with a self-protection function, including a shell and a slot, the top and bottom of the front end of the shell are respectively provided with slots, the center of the shell is fixed with a battery core, the front end of the shell is transversely provided with a cover plate, the top and bottom of the rear end of the cover plate are respectively fixedly welded with clamping strips, the two sides of the top and bottom of the front end of the shell are respectively provided with slide rails, and the front end of the cover plate is provided with a groove. The lithium battery module with a self-protection function is provided with a cover plate transversely at the front end of the shell, and the cover plate is spliced ​​to the front end of the shell by two transverse clamping strips provided at the rear, and then the shielding plate is pushed and pulled along the movable groove at the groove to open the plate covering the dust cover, so that the fan is exposed and the airflow is evacuated, and a longitudinal wiping strip is provided at the rear of the shielding plate to clean the mesh of the dust cover, thereby solving the problem of poor heat dissipation function.

[0004] However, this solution has the following problems: its fire extinguishing dry powder and fan are both located on the outside of the battery core, the heat of the battery core inside the battery pack cannot be discharged in time, and the packaging sleeve cannot be damaged in time when the battery core located inside burns or explodes. Fire extinguishing by fire extinguishing dry powder needs to be improved. Utility Model Content

[0005] The utility model aims to solve the problem that the battery cells inside the lithium battery module with self-protection function in the prior art cannot be extinguished in time when burning, and proposes a lithium battery module with fire extinguishing self-protection function.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A lithium battery module with a fire extinguishing and self-protection function comprises a battery cell holder, a lithium battery cell is installed inside the battery cell holder, the battery cell holder comprises a plurality of fire extinguishing units made of plastic, four of the fire extinguishing units enclose a second battery slot for wrapping the lithium battery cell, the lithium battery cell and the fire extinguishing unit are arranged alternately, the fire extinguishing unit comprises a shell, an alkali agent cavity is opened inside the shell, and the alkali agent cavity is filled with sodium bicarbonate powder.

[0008] Furthermore, an acid liquid chamber is arranged above the alkali agent chamber, the alkali agent chamber is separated from the diaphragm by a diaphragm, the melting point of the diaphragm is lower than the melting point of the shell, and the acid liquid chamber is filled with dilute hydrochloric acid solution.

[0009] Furthermore, a through hole is opened on the top of the shell, a top film is arranged in the through hole, and the thickness of the top film is smaller than the thickness of the shell.

[0010] Furthermore, a heat-conducting layer is embedded inside the diaphragm.

[0011] Furthermore, the heat-conducting layer is made of a heat-conducting insulating material.

[0012] Furthermore, an end of the heat-conducting layer passes through a side wall of the fire extinguishing unit.

[0013] Furthermore, a top seat is provided on the top of the battery holder, a first battery slot aligned with the second battery slot and a cover plate aligned with the acid chamber are provided on the top seat, a cover plate hole is opened on the cover plate, and the cover plate hole is aligned with the diaphragm.

[0014] Furthermore, a base is provided at the bottom of the battery cell holder, and the battery cell holder and the base are an integrally formed structure.

[0015] Compared with the prior art, the utility model provides a lithium battery module with fire extinguishing and self-protection function, which has the following beneficial effects:

[0016] The utility model discloses a lithium battery module with a fire extinguishing and self-protection function. When in use, the lithium battery cells are fixed together by a cell bracket to form a module for use. When a cell at any position in the module spontaneously ignites, a fire extinguishing unit and sodium bicarbonate powder around the spontaneously ignited cell are heated at high temperature. The sodium bicarbonate powder generates carbon dioxide and water. The carbon dioxide wraps around the cell to extinguish the fire source and put out the flame. Compared with the prior art, the structure of various parts inside the lithium battery module is protected and the loss is reduced.

[0017] Other advantages, objectives and features of the present invention will be described in the following description to some extent; and will be apparent to those skilled in the art based on the following examination and study to some extent; or, may be taught from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional schematic diagram of the overall structure of the utility model;

[0019] Figure 2 It is an exploded schematic diagram of the overall structure of the utility model;

[0020] Figure 3 for Figure 2A schematic diagram of the structure enlargement of part A;

[0021] Figure 4 This is a schematic diagram of the structure of the fire extinguishing unit of the utility model;

[0022] Figure 5 This is a schematic diagram of the internal structure of the fire extinguishing unit of the utility model;

[0023] Figure 6 for Figure 5 Schematic diagram of the enlarged structure of part B.

[0024] In the figure:

[0025] 1. Busbar; 2. Top seat; 3. Lithium battery cell; 4. Cell bracket; 5. Base; 6. First battery slot; 7. Cover plate; 8. Cover plate hole; 9. Fire extinguishing unit; 10. Second battery slot; 11. Shell; 12. Acid chamber; 13. Diaphragm; 14. Alkaline chamber; 15. Top film; 16. Thermal conductive layer. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0027] Reference Figure 1-6 The utility model provides a lithium battery module with a fire extinguishing and self-protection function, including a battery holder 4, a lithium battery cell 3 is installed inside the battery holder 4, the battery holder 4 includes a plurality of fire extinguishing units 9 made of plastic, four fire extinguishing units 9 enclose a second battery slot 10 for wrapping the lithium battery cell 3, the lithium battery cell 3 and the fire extinguishing unit 9 are arranged alternately, the fire extinguishing unit 9 includes a shell 11, an alkaline agent cavity 14 is opened inside the shell 11, and the alkaline agent cavity 14 is filled with sodium bicarbonate powder.

[0028] The plastic used to make the fire extinguishing unit 9 can be selected from existing plastics used to make internal brackets of lithium batteries, such as PCABS alloy material, which has excellent chemical properties. When the battery cell spontaneously ignites, the plastic and sodium bicarbonate powder are decomposed by heat. (Condition: heating), the generated carbon dioxide will diffuse around the ignition point, thereby enveloping the ignition point, reducing the contact between the battery material and oxygen, and achieving the purpose of fire extinguishing.

[0029] An acid liquid chamber 12 is disposed above the alkali agent chamber 14 . The alkali agent chamber 14 is separated from the diaphragm 13 by the diaphragm 13 . The melting point of the diaphragm 13 is lower than the melting point of the shell 11 . The acid liquid chamber 12 is filled with a dilute hydrochloric acid solution.

[0030] The dilute hydrochloric acid is selected to have a mass fraction of 20%. The diaphragm 13 can be made of ordinary heat-resistant plastics, such as polypropylene, PEEK, etc., which have good chemical stability and a melting point lower than that of PCABS alloy. When the combustion temperature is low at the beginning (200 degrees is taken as an example in this application), the diaphragm 13 melts before the battery support 4 and the fire extinguishing unit 9, so that the dilute hydrochloric acid and sodium bicarbonate are mixed and reacted. Compared with simply heating sodium bicarbonate, the reaction speed is faster and more intense, and a large amount of carbon dioxide is quickly released for fire extinguishing, which shortens the reaction time and achieves the effect of timely fire extinguishing. In addition, the reaction absorbs a large amount of heat, which can further improve the fire extinguishing effect.

[0031] A through hole is formed on the top of the shell 11 , and a top film 15 is disposed in the through hole. The thickness of the top film 15 is smaller than the thickness of the shell 11 .

[0032] The actual thickness of the top film 15 can be selected as needed. Specifically, the thickness of the top film 15 is smaller than the thickness of the shell 11. When dilute hydrochloric acid and sodium bicarbonate react to generate a large amount of carbon dioxide, the internal pressure of the fire extinguishing unit 9 increases, and the pressure breaks through the top film 15, causing the carbon dioxide to overflow from the through hole. The fire extinguishing begins before the fire extinguishing unit 9 melts, thereby achieving the effect of protecting the battery cell holder 4.

[0033] A heat conducting layer 16 is embedded in the diaphragm 13 .

[0034] The heat-conducting layer 16 is a mesh structure, which accelerates the heat transfer speed inside the diaphragm 13, so that the diaphragm 13 can melt quickly when combustion just occurs, triggering a fire extinguishing effect.

[0035] The heat conducting layer 16 is made of a heat conducting insulating material.

[0036] The thermally conductive insulating material includes aluminum oxide, aluminum nitride, thermally conductive insulating cloth, etc. The thermally conductive layer 16 is sandwiched in the diaphragm 13 to further increase the melting speed of the diaphragm 13, shorten the reaction time of triggering the fire extinguishing effect, and improve the fire extinguishing effect.

[0037] The end of the heat conductive layer 16 passes through the side wall of the fire extinguishing unit 9 .

[0038] Since the fire extinguishing unit 9 and the battery holder 4 are in direct contact with the battery cell, when the battery cell spontaneously ignites, the heat in the second battery container 10 can be directly transferred to the diaphragm 13 through the heat conductive layer 16 (the material of the battery holder 4 itself is flame retardant and heat insulating), ensuring that the diaphragm 13 melts quickly.

[0039] A top seat 2 is provided on the top of the battery holder 4 , on which a first battery slot 6 aligned with the second battery slot 10 and a cover plate 7 aligned with the acid chamber 12 are provided, and a cover plate hole 8 is opened on the cover plate 7 , which is aligned with the diaphragm 13 .

[0040] The top seat 2 covers the battery cell support 4 and is used to fix the lithium battery cell 3 and the top film 15, thereby reducing the risk of leakage of dilute hydrochloric acid due to damage to the top film 15 in other collision accidents without spontaneous combustion.

[0041] A base 5 is provided at the bottom of the battery cell support 4 , and the battery cell support 4 and the base 5 are an integrally formed structure.

[0042] The one-piece molding increases the overall structural strength of the battery holder 4 and the base 5. The top seat 2, the battery holder 4 and the base 5 are wrapped around the outside of the lithium battery cell 3 as a whole. Of course, the lithium battery module also has other structures, such as an overall protective shell, a control circuit board, etc., which are all mature existing technologies and will not be elaborated here.

[0043] Working principle: When the battery cell in this module spontaneously combusts, as the temperature rises, the heat conductive layer 16 quickly transfers the heat in the second battery compartment 10 to the diaphragm 13, and the diaphragm 13 melts, causing the dilute hydrochloric acid and sodium bicarbonate to mix and react, absorbing a large amount of heat to curb the burning speed of the battery cell, while producing water and carbon dioxide. Since the combustion of lithium batteries is mainly gas combustion, the generated carbon dioxide can effectively block the contact between the combustible gas and oxygen after being wrapped around the combustion point, thereby extinguishing the fire.

[0044] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

[0045] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0046] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A lithium battery module with a fire extinguishing and self-protection function, comprising a battery cell support (4), wherein a lithium battery cell (3) is installed inside the battery cell support (4), characterized in that: The battery cell support (4) comprises a plurality of fire extinguishing units (9) made of plastic, four of the fire extinguishing units (9) enclosing a second battery slot (10) for wrapping a lithium battery cell (3), the lithium battery cell (3) and the fire extinguishing units (9) being arranged in a staggered manner, the fire extinguishing unit (9) comprising a shell (11), an alkali agent cavity (14) being provided inside the shell (11), and the alkali agent cavity (14) being filled with sodium bicarbonate powder.

2. The lithium battery module with fire extinguishing and self-protection function according to claim 1, characterized in that: An acid liquid chamber (12) is arranged above the alkali agent chamber (14); the alkali agent chamber (14) and the diaphragm (13) are separated by the diaphragm (13); the melting point of the diaphragm (13) is lower than the melting point of the shell (11); and the acid liquid chamber (12) is filled with a dilute hydrochloric acid solution.

3. The lithium battery module with fire extinguishing and self-protection function according to claim 2, characterized in that: A through hole is provided on the top of the shell (11), a top film (15) is arranged in the through hole, and the thickness of the top film (15) is smaller than the thickness of the shell (11).

4. The lithium battery module with fire extinguishing and self-protection function according to claim 2, characterized in that: A heat-conducting layer (16) is embedded inside the diaphragm (13).

5. The lithium battery module with fire extinguishing and self-protection function according to claim 4, characterized in that: The heat-conducting layer (16) is made of a heat-conducting insulating material.

6. The lithium battery module with fire extinguishing and self-protection function according to claim 4, characterized in that: An end portion of the heat-conducting layer (16) penetrates the side wall of the fire extinguishing unit (9).

7. The lithium battery module with fire extinguishing and self-protection function according to claim 1, characterized in that: A top seat (2) is provided on the top of the battery cell support (4); a first battery slot (6) aligned with the second battery slot (10) and a cover plate (7) aligned with the acid chamber (12) are provided on the top seat (2); a cover plate hole (8) is provided on the cover plate (7); and the cover plate hole (8) is aligned with the diaphragm (13).

8. The lithium battery module with fire extinguishing and self-protection function according to claim 1, characterized in that: A base (5) is provided at the bottom of the battery cell support (4), and the battery cell support (4) and the base (5) are an integrally formed structure.

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