Lithium battery assembly and lithium battery packaging case

Abstract

The application relates to the technical field of secondary batteries, in particular to a high-efficiency lithium battery assembly and a lithium battery packaging shell, which comprises a packaging shell and a matched packaging cover, a plurality of lithium batteries are arranged in an array in the inner cavity of the packaging shell, each lithium battery in the packaging shell is provided with a hollow tube arranged in the packaging shell, a connecting rod is fixedly arranged between the plurality of hollow tubes, a blind hole with an upward opening is arranged in the connecting rod, a liquid compound of acetic acid is arranged in the blind hole, a plugging piece is arranged above the blind hole, a solid compound of sodium bicarbonate is arranged in the plugging piece, a positioning ring made of the plugging piece is arranged on the top of the inner circumferential surface of the hollow tube, the lithium battery penetrates through the positioning ring and is in interference fit with the positioning ring; the application can discharge the burning battery out of the packaging shell, prevent the burning battery from continuously generating flames to affect the adjacent batteries, and continuously inject CO2 into the packaging shell after the discharge to extinguish the generated flames.

Description

Technical Field

[0001] This invention relates to the field of secondary battery technology, specifically to lithium battery components and lithium battery packaging housings. Background Technology

[0002] Thermoplastic polyurethane elastomer (TPU): normal ignition point >200°C, burning rate 18 cm / s; flame-retardant polyurethane elastic foam (PUR Foam): burning rate 10-20 cm / s; normal ignition point: by adding flame retardants (such as magnesium hydroxide, phosphorus compounds), the ignition point can be increased to above 250°C. Lithium battery combustion is mainly due to thermal runaway, internal short circuits or external high temperatures triggering electrolyte decomposition, releasing flammable gases, which then burn or even explode. When one battery catches fire, the surrounding temperature rises, which may affect nearby batteries through heat conduction, radiation, or gas diffusion.

[0003] When lithium batteries are used, the battery pack needs to be encapsulated and protected by a shell to ensure the safety of the battery during discharge. It is a type of secondary battery. In the current technology, most batteries are fixedly installed in the encapsulation shell to form a battery pack. The battery pack is located at the bottom of the vehicle body. Long-term collisions and vibrations during vehicle operation will accelerate battery aging.

[0004] If any battery cell in a battery module experiences thermal runaway and the runaway worsens, the battery cell will emit high-temperature gas and sparks, causing thermal damage to surrounding battery modules and triggering a chain reaction that could lead to a vehicle fire.

[0005] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to design a battery enclosure that, when a lithium battery catches fire, will expel the burning lithium battery from the enclosure and continuously apply extinguishing gas to prevent the flame from spreading, thereby overcoming the aforementioned shortcomings in the technology.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a lithium battery packaging shell, comprising a packaging shell and a matching packaging cover, wherein the inner cavity of the packaging shell contains a plurality of lithium batteries arranged in an array, each lithium battery in the packaging shell has a hollow tube installed in the packaging shell, a connecting rod is fixedly installed between the plurality of hollow tubes, the connecting rod has an upward-opening blind hole, the blind hole contains a liquid compound, a sealing plate is sealed above the blind hole, the sealing plate contains a solid compound, a positioning ring integrally formed with the sealing plate is installed on the top of the inner circumference of the hollow tube, the lithium battery passes through the positioning ring and is interference-fitted with the positioning ring, and a bottom sleeve that mates with the bottom of the lithium battery is also fixedly installed in the hollow tube, the bottom sleeve, the sealing plate and the positioning ring are all made of fast-burning elastic material;

[0008] When one of the lithium batteries catches fire, it ignites the positioning ring at the top used for buffer positioning and the bottom sleeve at the bottom. The positioning ring, through its integration with the sealing plate, ignites all the positioning rings and sealing plates, consuming the oxygen inside the encapsulation shell and causing the solid compound to fall into the liquid compound under the action of gravity. The reaction generates fire extinguishing gas, which pressurizes the encapsulation shell, allowing the burning lithium battery to be discharged from the hollow tube into the encapsulation shell under the action of gravity and pressure.

[0009] Preferably, a top plate is fixedly installed on the top of multiple hollow tubes, and a stop plate that cooperates with the top plate is fixedly installed on the inner surface of the bottom of the encapsulation housing. The hollow tubes pass through the stop plate and are slidably connected to the stop plate. A support strip is fixedly installed between the stop plate and the top plate, and the support strip contacts the positioning ring.

[0010] Preferably, the support bar, the positioning ring, the bottom sleeve, and the sealing plate are all PUR or TPU material components.

[0011] Preferably, after the support strip burns, the top piece descends under gravity to fit against the stop piece, forming an isolation chamber between the top piece, the encapsulation housing, and the encapsulation cover.

[0012] Preferably, a connecting groove is provided at the connection between the positioning ring and the connecting rod, and a connecting block for connecting the positioning ring and the sealing plate is provided in the connecting groove. The connecting block is a component made of PUR or TPU material.

[0013] Preferably, the solid compound is sodium bicarbonate and the liquid compound is acetic acid.

[0014] Preferably, both the hollow tubes and the connecting rods are arranged in a linear array at intervals, and there is a connecting rod between two adjacent hollow tubes.

[0015] Preferably, a negative electrode plate that contacts the negative terminal of the battery is installed inside the bottom sleeve, a negative electrode solder strip is fixedly installed at the bottom of the stop plate, and a wire is fixedly connected between the negative electrode solder strip and the negative electrode plate, with the wire passing through the bottom sleeve.

[0016] Preferably, a positive electrode solder bar is fixedly installed at the bottom of the encapsulation cover. When the encapsulation cover is fixedly installed on the encapsulation housing, the positive electrode solder bar is in contact with all the positive electrodes of the lithium batteries inside the encapsulation housing.

[0017] Secondly, the present invention also provides a lithium battery assembly for mounting in a lithium battery encapsulation housing as described in any one of claims 1-9, the lithium battery assembly comprising at least two battery cells connected in parallel via the positive electrode solder bar 20 and the negative electrode solder bar 18.

[0018] The technical effects and advantages provided by the present invention in the above technical solution are as follows:

[0019] This invention removes the burning battery from the encapsulation housing to prevent it from continuing to generate flames that could affect adjacent batteries. Furthermore, it continuously injects CO2 into the encapsulation housing after removal to extinguish any existing flames, further preventing a chain reaction that could cause a vehicle fire.

[0020] When the lithium battery is not on fire, the positioning ring and the bottom sleeve will buffer and position the battery to reduce the impact of vibration generated during vehicle operation. After the battery burns, the bottom sleeve and the positioning ring will no longer fix the battery in the hollow tube, but will burn directly along with it, so that the lithium battery will be discharged from the encapsulation shell through the hollow tube under the action of gravity.

[0021] Meanwhile, after a single battery burns, all positioning rings, sealing pieces, connecting blocks, and support bars will be quickly and synchronously ignited. Due to the rapid combustion, it will not continuously heat other lithium batteries. During combustion, it will consume some of the oxygen in the encapsulation shell, further preventing the flame from spreading.

[0022] In this invention, after the support strip disappears, hollow tubes and other components will descend under the action of gravity until the top plate and the stop plate come into contact, forming an isolation chamber. At this time, the distance between the burning lithium battery and the encapsulation cover increases, the ignition effect of the flame on the encapsulation cover decreases, and sufficient reaction time is given to generate a sufficient amount of CO2.

[0023] Furthermore, the reaction between the solid reactants and the liquid reactants in this invention is an endothermic reaction. Therefore, the connecting rod 4 will absorb the heat from the adjacent hollow tubes, thereby absorbing the heat from the adjacent unignited lithium batteries and preventing the adjacent lithium batteries from being spread and ignited. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0025] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0026] Figure 2 This is a schematic diagram of the bottom structure of the present invention;

[0027] Figure 3 This is a schematic diagram showing the internal structure of the packaging shell of the present invention.

[0028] Figure 4 This is a schematic diagram showing the disassembled sealing plate and connecting rod of the present invention;

[0029] Figure 5 This is a schematic diagram showing the connection between the hollow tube and the support strip of the present invention;

[0030] Figure 6 This is a cross-sectional view of the packaging housing of the present invention;

[0031] Figure 7 This is a schematic diagram of the distribution of the isolation chambers in this invention;

[0032] Figure 8 This is a schematic diagram of the internal structure of the connecting rod of the present invention.

[0033] Explanation of reference numerals in the attached figures:

[0034] 1. Encapsulation housing; 2. Encapsulation cover; 3. Hollow tube; 4. Connecting rod; 5. Blind hole; 6. Liquid compound; 7. Sealing plate; 8. Solid compound; 9. Positioning ring; 10. Bottom sleeve; 11. Top plate; 12. Stop plate; 13. Support bar; 14. Isolation chamber; 15. Connecting groove; 16. Connecting block; 17. Negative electrode plate; 18. Negative electrode solder bar; 19. Wire; 20. Positive electrode solder bar. Detailed Implementation

[0035] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0037] This invention provides, for example Figure 1-8 The lithium battery packaging shell shown includes a packaging shell 1 and a matching packaging cover 2. A top plate 11 is vertically slidably installed inside the packaging shell 1. Multiple hollow tubes 3 and connecting rods 4 are fixedly installed in a linear array and intermittently arranged inside the top plate 11. The top plate 11, hollow tubes 3, and connecting rods 4 are all integrally formed from aluminum products. The connection point of two adjacent hollow tubes 3 must be connected to a connecting rod 4 to ensure that the connecting rod 4 absorbs heat from the adjacent hollow tubes 3 simultaneously when cooling down, thus assisting in cooling. A blind hole 5 with an upward opening is opened inside the connecting rod 4. The blind hole 5 stores liquid compound 6 acetic acid. A sealing piece 7 for sealing is interference fitted at the top of the blind hole 5. The sealing piece 7 contains solid compound 8 sodium bicarbonate. The reaction formula between the two is: 2NaHCO3 + CH3COOH → CH3COONa + 2CO2↑ + 2H2O. A 5% concentration of dilute acetic acid with pH≈2.5 can be used, which can generate enough to cover 1 m within 30 seconds. 3The CO2 in the space reacts endothermally (ΔH≈-20 kJ / mol), which can reduce the surface temperature of the battery and suppress thermal runaway. A positioning ring 9 is fixedly installed on the top of the inner circumferential surface of the hollow tube 3, and a bottom sleeve 10 is fixedly installed on the bottom of the inner circumferential surface. The bottom sleeve 10 has a negative electrode plate 17 on its top. A lithium battery is inserted into the positioning ring 9, and the bottom of the lithium battery contacts the negative electrode plate 17. The bottom sleeve 10 covers the bottom of the lithium battery, isolating it from the outside environment. To ensure the connection between the positioning ring 9 and the sealing plate 7, a connecting groove 15 is opened between the top of the hollow tube 3 and the connecting rod 4. A connecting block 16 connecting the sealing plate 7 and the positioning ring 9 is placed in the connecting groove 15. The connecting block 16, the positioning ring 9, and the sealing plate 7 are made as a single unit and are all made of PUR or TPU material. They have a fast combustion speed when burning, which can quickly consume the oxygen in the encapsulation shell 1. When not burning, they have... The elasticity acts as a buffer and positions the lithium battery. A stop plate 12 is fixedly installed on the inner wall of the encapsulation shell 1. A hollow tube 3 passes through the stop plate 12 and is slidably connected to the stop plate 12. Between the stop plate 12 and the top plate 11, there is a support strip 13 made of the same material as the positioning ring 9. The support strip 13 contacts the positioning ring 9 and can also contact the connecting block 16, as long as it can be ignited by the connecting block 16, the positioning ring 9, and the sealing plate 7. A negative electrode solder strip 18 is fixedly installed at the bottom of the stop plate 12. A wire 19 is fixedly installed between the negative electrode solder strip 18 and the negative electrode plate 17. The wire 19 passes through the bottom sleeve 10. A positive electrode solder strip 20 that contacts the positive electrode of the lithium battery is fixedly installed at the bottom of the encapsulation cover 2. The thickness of the positioning ring 9 and the sealing plate 7 is 0.1 times or less of the height of the lithium battery. It is only necessary to ensure that the liquid compound 6 does not flow out from the blind hole 5. After the support strip 13 burns, the top piece 11 descends under the action of gravity to fit with the stop piece 12. An isolation chamber 14 is formed between the top piece 11, the encapsulation shell 1 and the encapsulation cover 2, which increases the distance between the lithium battery and the encapsulation cover 2 and forms a space to accommodate the formation of CO2, extinguishing the flames on the inner surface of the encapsulation cover 2 and the encapsulation shell 1.

[0038] When the lithium batteries are not on fire, the bottom sleeve 10 and positioning ring 9 will position and buffer the lithium batteries within the hollow tube 3. When one lithium battery catches fire, the flames it produces will ignite the bottom sleeve 10 and the top positioning ring 9. Since the positioning ring 9, sealing plate 7, and connecting block 16 are integrated, and the support bar 13 is in contact with the positioning ring 9 or the connecting block 16, all positioning rings 9, sealing plates 7, connecting blocks 16, and support bars 13 will be rapidly and synchronously ignited. Due to the rapid combustion, it will not continuously heat other lithium batteries. Other lithium batteries are not ignited, and their combustion will consume some of the oxygen inside the encapsulation shell 1. After the support bar 13 disappears, the hollow tube 3 and other components will descend under gravity until the top plate 11 contacts the stop plate 12, forming the isolation chamber 1. 4. At this time, the distance between the burning lithium battery and the encapsulation cover 2 increases, the ignition effect of the flame on the encapsulation cover 2 is reduced, and sufficient reaction time is given to generate a sufficient amount of CO2. The lithium battery will also be removed from the hollow tube 3 under the action of gravity, thereby avoiding continuous flame spraying onto the encapsulation shell 1. After the sealing sheet 7 burns, the solid compound 8 sodium bicarbonate stored inside, preferably pressed into a piece, will fall into the liquid compound 6 acetic acid under the action of gravity, react to generate CO2, and the CO2 will quickly fill the isolation chamber 14 to extinguish the existing flame in the isolation chamber 14. At the same time, since the reaction is an endothermic reaction, the connecting rod 4 will absorb the heat from the adjacent hollow tube 3, thereby absorbing the heat from the adjacent unburned lithium battery and preventing the adjacent lithium battery from being spread and ignited.

[0039] Secondly, the present invention also provides a lithium battery assembly for mounting in a lithium battery encapsulation housing as described in any one of claims 1-9. The lithium battery assembly includes at least two lithium battery cells, which are connected in parallel via the positive electrode solder bar 20 and the negative electrode solder bar 18. The more lithium battery cells there are, the higher the voltage of the lithium battery assembly formed by the combination.

[0040] It is important to note that the constructions and arrangements of this application shown in several different exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in this disclosure, those who consult this disclosure will readily understand that many modifications are possible (e.g., changes in the size, dimensions, structure, shape and proportion of various elements, as well as parameter values ​​(e.g., temperature, pressure, etc.), installation arrangements, use of materials, color, orientation, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in this application.

Claims

1. A lithium battery packaging housing, comprising a packaging housing (1) and a matching packaging cover (2), wherein the inner cavity of the packaging housing (1) has a plurality of lithium batteries arranged in an array, characterized in that: Each lithium battery inside the encapsulation housing (1) has a hollow tube (3) installed inside the encapsulation housing (1). A connecting rod (4) is fixedly installed between multiple hollow tubes (3). The connecting rod (4) has an upward-opening blind hole (5). The blind hole (5) contains a liquid compound (6) of acetic acid. A sealing plate (7) is sealed above the blind hole (5). The sealing plate (7) contains a solid compound (8) of sodium bicarbonate. A positioning ring (9) integrally formed with the sealing plate (7) is installed on the top of the inner circumference of the hollow tube (3). The lithium battery passes through the positioning ring (9) and is press-fitted to the positioning ring (9). A bottom sleeve (10) that fits the bottom of the lithium battery is also fixedly installed inside the hollow tube (3). The bottom sleeve (10), the sealing plate (7) and the positioning ring (9) are all made of fast-burning elastic material. When one of the lithium batteries catches fire, it will ignite the positioning ring (9) at the top and the bottom sleeve (10) at the bottom. The positioning ring (9) will ignite all the positioning rings (9) and the sealing plate (7) through integration with the sealing plate (7), consuming the oxygen in the encapsulation shell (1) and causing the solid compound (8) to fall into the liquid compound (6) under the action of gravity. The reaction generates fire extinguishing gas, which pressurizes the encapsulation shell (1) and allows the burning lithium battery to be discharged from the hollow tube (3) into the encapsulation shell (1) under the action of gravity and pressure.

2. The lithium battery packaging housing according to claim 1, characterized in that: A top plate (11) is fixedly installed on the top of multiple hollow tubes (3). A stop plate (12) that cooperates with the top plate (11) is fixedly installed on the bottom inner surface of the encapsulation housing (1). The hollow tube (3) passes through the stop plate (12) and is slidably connected to the stop plate (12). A support strip (13) is fixedly installed between the stop plate (12) and the top plate (11). The support strip (13) contacts the positioning ring (9).

3. A lithium battery packaging housing according to claim 2, characterized in that: The support bar (13), the positioning ring (9), the bottom sleeve (10), and the sealing plate (7) are all PUR or TPU material components.

4. A lithium battery packaging housing according to claim 2, characterized in that: After the support strip (13) is burned, the top piece (11) descends under the action of gravity to fit with the stop piece (12), and an isolation chamber (14) is formed between the top piece (11), the encapsulation shell (1) and the encapsulation cover (2).

5. A lithium battery packaging housing according to claim 1, characterized in that: A connecting groove (15) is provided at the connection between the positioning ring (9) and the connecting rod (4). The connecting groove (15) contains a connecting block (16) that connects the positioning ring (9) and the sealing piece (7). The connecting block (16) is a component made of PUR or TPU material.

6. A lithium battery packaging housing according to claim 1, characterized in that: The hollow tubes (3) and the connecting rods (4) are arranged in a linear array at intervals, with a connecting rod (4) between two adjacent hollow tubes (3).

7. A lithium battery packaging housing according to claim 2, characterized in that: The bottom sleeve (10) is equipped with a negative electrode sheet (17) that contacts the negative electrode of the lithium battery. A negative electrode solder bar (18) is fixedly installed at the bottom of the stop plate (12). A wire (19) is fixedly connected between the negative electrode solder bar (18) and the negative electrode sheet (17). The wire (19) passes through the bottom sleeve (10).

8. A lithium battery packaging housing according to claim 7, characterized in that: A positive electrode solder bar (20) is fixedly installed at the bottom of the encapsulation cover (2). When the encapsulation cover (2) is fixedly installed on the encapsulation housing (1), the positive electrode solder bar (20) is in contact with the positive electrodes of all the lithium batteries inside the encapsulation housing (1).

9. A lithium battery assembly for mounting in a lithium battery encapsulation housing as described in claim 8, characterized in that: The lithium battery assembly includes at least two lithium battery cells, which are connected in parallel via the positive electrode tin bar (20) and the negative electrode tin bar (18).

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