A lithium battery sealing explosion-proof shell

Abstract

The utility model relates to lithium battery safety protection technical field, specifically disclose a kind of lithium battery sealing explosion-proof shell, comprising: shell main part, it is the main shell structure for containing lithium battery, shell main part top opening place covers and locates top cover, and shell main part and the edge of positioning top cover are detachably sealed connection by bolt.This lithium battery sealing explosion-proof shell, through the multiple groups of pressure relief holes on the gas seat of the explosion-proof valve assembly around arrangement, improve the discharge efficiency, combine the gas guiding effect of auxiliary positioning frame through-hole, ensure that the large amount of high-temperature and high-pressure gas produced when lithium battery body violent thermal runaway rapidly diffuses, high-efficiency discharge, avoid shell internal pressure to exceed material strength limit in short time, prevent shell rupture explosion, avoid to cause secondary damage to surrounding battery and equipment, the cone structure and L-shaped frame of gas seat, further guarantee the stable of shell pressure relief process, improve shell explosion-proof reliability.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery safety protection technology, specifically a sealed explosion-proof housing for lithium batteries. Background Technology

[0002] As a core energy storage component in the new energy field, lithium batteries are widely used in electric vehicles, energy storage devices, consumer electronics and other scenarios. Their safety performance directly determines the reliability of equipment operation and the safety of people and property. At present, the sealed explosion-proof housing of lithium batteries is usually made of metal materials through stretching or welding processes. Its basic structure includes a cylinder for accommodating the battery cells, a cover plate that seals with the cylinder, and an explosion-proof device installed on the cover plate or housing.

[0003] In actual use, most existing explosion-proof enclosures for lithium batteries place the explosion-proof valve at the top or bottom. When depressurization occurs at the top, the gas and electrolyte released can easily cause harm to the human body. Depressurization at the bottom can cause the battery to shift due to the reaction force of the gas pressure. Moreover, most existing explosion-proof enclosures adopt a single-point pressure relief structure. When a severe thermal runaway occurs inside the battery, the gas generation rate far exceeds the release capacity of a single explosion-proof valve, causing the internal pressure of the enclosure to exceed the material strength limit in a very short time. At this time, the opening area of ​​the explosion-proof structure is insufficient, and the enclosure will still explode uncontrollably in the weak corners, generating high-speed fragments that cause secondary damage to surrounding battery cells and equipment. Utility Model Content

[0004] The purpose of this invention is to provide a sealed explosion-proof housing for lithium batteries, in order to solve the problems mentioned in the background art, where the explosion-proof valve is placed at the top or bottom of the housing. When the pressure is released at the top, the gas and electrolyte discharged can easily cause harm to the human body. When the pressure is released at the bottom, the battery will shift due to the gas pressure reaction force. Moreover, most existing explosion-proof housings adopt a single-point pressure relief structure. When a violent thermal runaway occurs inside the battery, the gas generation rate far exceeds the release capacity of a single explosion-proof valve, causing the internal pressure of the housing to exceed the material strength limit in a very short time, causing secondary damage to the surrounding battery cells and equipment.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a sealed explosion-proof housing for a lithium battery, comprising a housing body, which is the main housing structure for accommodating the lithium battery, wherein a positioning top cover is fitted over the top opening of the housing body, and the edges of the housing body and the positioning top cover are detachably and sealed together by bolts;

[0006] The bottom inner wall of the housing body is provided with a cell lower positioning seat, and the bottom gasket is embedded in the cell lower positioning seat. The top of the cell lower positioning seat is symmetrically provided with positioning supports, and the positioning supports are above the bottom gasket. The top of the cell lower positioning seat is embedded with the lithium battery body.

[0007] An auxiliary positioning frame is provided at the top of the inner wall of the main body of the housing, and an annular sealing ring is embedded in the inner wall of the auxiliary positioning frame. The auxiliary positioning frame is located on the top of the lithium battery body, and the top of the lithium battery body abuts against the inner side of the annular sealing ring. Flow holes for gas flow are equidistantly opened on the auxiliary positioning frame. A terminal block and an explosion-proof valve assembly are embedded at the top of the positioning top cover, and the explosion-proof valve assembly surrounds the terminal block.

[0008] By adopting the above technical solution, the lithium battery body is stably positioned and the casing is double-sealed, preventing electrolyte leakage and impurity intrusion.

[0009] Preferably, heat dissipation fins are equidistantly arranged at the bottom of the outer wall of the housing body, and the heat dissipation fins are evenly arranged along the bottom outer edge of the housing body and fixed to the housing body by laser welding.

[0010] Using the above technical solution, the heat dissipation fins quickly dissipate the working heat of the lithium battery body, avoiding overheating and thermal runaway. Laser welding fixation ensures stable heat dissipation efficiency and reduces the safety hazards of lithium batteries.

[0011] Preferably, a cell limiting frame is fitted and installed at the top of the positioning support, and the cell limiting frame is engaged and connected to the side wall of the lithium battery body. The two sides of the lithium battery body are respectively secured between the two positioning supports by the cell limiting frame.

[0012] The above technical solution uses a cell limiting frame in conjunction with a positioning support to enhance the positioning stability of the lithium battery body, prevent it from shifting or colliding, and further eliminate vibration damage in conjunction with a bottom pad.

[0013] Preferably, the top of the positioning cover is provided with a hole adapted to the installation of the explosion-proof valve assembly, and a sealing ring is provided at the connection between the positioning cover and the housing body.

[0014] By adopting the above technical solution, the holes in the positioning top cover ensure the stable installation of the explosion-proof valve assembly, and the sealing ring at the connection enhances the sealing performance of the shell, preventing electrolyte leakage and the intrusion of external impurities.

[0015] Preferably, the explosion-proof valve assembly includes an explosion-proof valve stem, an explosion-proof valve seat, a vent seat, a pressure relief valve disc, a return spring, and a safety contact edge. The explosion-proof valve stem is installed at the top of the positioning top cover hole, the explosion-proof valve seat is installed at the bottom of the positioning top cover hole, and the explosion-proof valve stem is installed vertically at the top of the explosion-proof valve seat.

[0016] By adopting the above technical solution, the various parts of the explosion-proof valve assembly work together to achieve automatic pressure relief, power cut-off and reset in case of abnormality, without the need for manual operation, thus improving the reliability and automation of explosion protection.

[0017] Preferably, the top of the explosion-proof valve seat is engaged with a vent seat, and the vent seat has pressure relief holes equidistantly opened. The top of the vent seat has a conical structure, and its side wall is equidistantly provided with L-shaped frames to support the pressure relief valve disc.

[0018] By adopting the above technical solution, the structural design of the vent seat improves the pressure relief efficiency, and the L-shaped frame stably supports the pressure relief valve disc, ensuring a smooth pressure relief process and avoiding secondary damage caused by concentrated gas jets.

[0019] Preferably, the top of the cone of the vent seat and the top of the L-shaped frame abut against the bottom of the pressure relief valve disc, and a return spring is provided between the vent seat and the pressure relief valve disc. A safety contact edge is provided below the pressure relief valve disc along the side wall of the positioning top cover hole, and the contact surface of the safety contact edge faces the side wall of the vent seat. The safety contact edge is electrically connected to the wiring terminal.

[0020] The above technical solution ensures smooth pressure relief by the contact between the vent seat and the pressure relief valve disc. The safety contact edge can trigger the terminal block to stop power supply. The reset spring automatically resets after pressure relief, restoring the sealing protection and eliminating secondary safety hazards.

[0021] Compared with the prior art, the beneficial effects of this utility model are: the lithium battery sealed explosion-proof housing:

[0022] 1. By embedding the explosion-proof valve assembly into the positioning top cover and surrounding the wiring terminals, and in conjunction with the flow holes on the auxiliary positioning frame and the pressure relief holes on the vent seat, the high-temperature and high-pressure gas can be released in a directional and stable manner. At the same time, with the coordinated fixation of the lithium battery body by the lower positioning seat, positioning support, and battery cell limiting frame, as well as the buffering effect of the bottom pad, the pressure relief reaction force is offset, preventing battery displacement and avoiding safety risks.

[0023] 2. The surrounding explosion-proof valve assembly and multiple pressure relief holes on the vent seat improve the release efficiency. Combined with the gas guiding effect of the flow hole of the auxiliary positioning frame, it ensures that the large amount of high-temperature and high-pressure gas generated when the lithium battery body undergoes severe thermal runaway can be rapidly diffused and efficiently discharged. This prevents the internal pressure of the casing from exceeding the material strength limit in a short time, thus preventing the casing from rupturing and exploding, and avoiding secondary damage to surrounding cells and equipment. The conical structure and L-shaped frame of the vent seat further ensure a smooth pressure relief process and improve explosion-proof reliability.

[0024] 3. During normal operation, the heat dissipation fins quickly dissipate the heat from the lithium battery body, preventing overheating and thermal runaway. The bottom pad provides insulation and buffering, preventing short circuits and vibration damage. The wiring terminals ensure stable and sealed power supply. In case of abnormality, the safety contact edge can trigger the wiring terminals to stop power supply, and the reset spring pushes the vent seat and pressure relief valve to reset, restoring the sealed protection. The entire process is automatic and requires no manual operation. The bolts connecting the main body of the housing and the positioning top cover are detachable, facilitating inspection and maintenance. Combined with the stabilizing effect of various protective structures, the long-term safety protection effectiveness of the housing is improved. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall external three-dimensional structure of this utility model;

[0026] Figure 2 This is a schematic diagram of the overall disassembled three-dimensional structure of this utility model;

[0027] Figure 3 This is a schematic diagram of the overall internal side section of the present invention.

[0028] Figure 4 This is a schematic diagram of the overall internal three-dimensional structure of this utility model;

[0029] Figure 5 This is a side-sectional three-dimensional structural diagram of the positioning top cover and explosion-proof valve assembly of this utility model;

[0030] Figure 6 This utility model Figure 5 Enlarged structural diagram at point A in the middle.

[0031] In the diagram: 1. Main body of the casing; 2. Lower positioning seat of the battery cell; 3. Heat dissipation fins; 4. Bottom gasket; 5. Positioning support; 6. Battery cell limiting frame; 7. Lithium battery body; 8. Auxiliary positioning frame; 9. Annular sealing ring; 10. Positioning top cover; 11. Wiring terminal; 12. Explosion-proof valve assembly; 1201. Explosion-proof valve stem; 1202. Explosion-proof valve seat; 1203. Vent seat; 1204. Pressure relief valve disc; 1205. Return spring; 1206. Safety contact edge. Detailed Implementation

[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0033] Please see Figures 1-6This utility model provides a technical solution: a sealed explosion-proof housing for a lithium battery, including a housing body 1, a lower positioning seat for the battery cell 2, heat dissipation fins 3, a bottom gasket 4, a positioning support 5, a battery cell limiting frame 6, a lithium battery body 7, an auxiliary positioning frame 8, an annular sealing ring 9, a positioning top cover 10, a wiring terminal 11, an explosion-proof valve assembly 12, an explosion-proof valve stem 1201, an explosion-proof valve seat 1202, a vent seat 1203, a pressure relief valve disc 1204, a return spring 1205, and a safety contact edge 1206;

[0034] Among them, the housing body 1 is the main housing structure that houses the lithium battery. The top opening of the housing body 1 is covered by the positioning top cover 10, and the edges of the housing body 1 and the positioning top cover 10 are detachably and sealed by bolts.

[0035] The bottom inner wall of the housing body 1 is provided with a cell lower positioning seat 2, and the bottom pad 4 is embedded in the cell lower positioning seat 2. The bottom of the outer wall of the housing body 1 is provided with heat dissipation fins 3 at equal intervals, and the heat dissipation fins 3 are evenly arranged along the bottom outer edge of the housing body 1 and fixed to the housing body 1 by laser welding. The top of the cell lower positioning seat 2 is symmetrically provided with positioning supports 5, and the positioning supports 5 are above the bottom pad 4. The top of the cell lower positioning seat 2 is embedded with a lithium battery body 7. The top of the positioning support 5 is fitted with a cell limiting frame 6, and the cell limiting frame 6 is engaged and connected to the side wall of the lithium battery body 7. The two sides of the lithium battery body 7 are respectively secured between the two positioning supports 5 by the cell limiting frame 6.

[0036] Referring to the attached diagrams in the instruction manual Figures 1-6 As shown, first fix the lower positioning seat 2 of the battery cell to the bottom inner wall of the main body 1 of the housing, and then embed the bottom pad 4, which plays the role of insulation buffer and short circuit prevention, into the lower positioning seat 2 of the battery cell.

[0037] Positioning supports 5 are symmetrically installed on the top of the lower positioning seat 2 of the battery cell. The battery cell limiting frame 6 is fitted and installed on the top of the positioning support 5. Then, the lithium battery body 7 is fitted into the lower positioning seat 2 of the battery cell, so that its two sides are engaged with the battery cell limiting frame 6 to achieve lateral limiting and prevent displacement and collision.

[0038] An annular sealing ring 9 is embedded in the inner wall of the auxiliary positioning frame 8. The auxiliary positioning frame 8 is installed on the top of the inner wall of the housing body 1 and above the lithium battery body 7, ensuring that the top of the lithium battery body 7 is in close contact with the annular sealing ring 9. A pressure relief channel is reserved using the flow hole on the auxiliary positioning frame 8.

[0039] The positioning top cover 10 is placed on the top of the housing body 1, and a detachable and sealed connection is achieved with bolts to prevent external impurities from entering and electrolyte leakage. Finally, the wiring terminal 11 and the explosion-proof valve assembly 12 are embedded in the positioning top cover 10, so that the explosion-proof valve assembly 12 surrounds the wiring terminal 11. The parts of the explosion-proof valve assembly 12 are assembled in sequence: the explosion-proof valve seat 1202 and the explosion-proof valve stem 1201 are respectively installed at the bottom and top of the hole in the positioning top cover 10, the vent seat 1203 is engaged at the top of the explosion-proof valve seat 1202, the return spring 1205 is placed between the vent seat 1203 and the pressure relief valve disc 1204, and the safety contact 1206 is installed below the pressure relief valve disc 1204 and on the side wall of the hole in the positioning top cover 10, ensuring that the contact surface of the safety contact 1206 faces the vent seat 1203, thus completing the assembly of the explosion-proof protection structure.

[0040] An auxiliary positioning frame 8 is provided at the top of the inner wall of the main body 1, and an annular sealing ring 9 is embedded in the inner wall of the auxiliary positioning frame 8. The auxiliary positioning frame 8 is located at the top of the lithium battery body 7, and the top of the lithium battery body 7 abuts against the inner side of the annular sealing ring 9. Flow holes for gas flow are provided at equal intervals on the auxiliary positioning frame 8. A terminal block 11 and an explosion-proof valve assembly 12 are embedded at the top of the positioning top cover 10, and the explosion-proof valve assembly 12 surrounds the periphery of the terminal block 11. The top of the positioning top cover 10 is provided with a hole that is compatible with the installation of the explosion-proof valve assembly 12, and a sealing ring is provided at the connection between the positioning top cover 10 and the main body 1.

[0041] The explosion-proof valve assembly 12 includes an explosion-proof valve stem 1201, an explosion-proof valve seat 1202, a vent seat 1203, a pressure relief valve disc 1204, a return spring 1205, and a safety contact edge 1206. The explosion-proof valve stem 1201 is installed at the top of the hole in the positioning cover 10, and the explosion-proof valve seat 1202 is installed at the bottom of the hole in the positioning cover 10. The explosion-proof valve stem 1201 is vertically mounted on the top of the explosion-proof valve seat 1202. The top of the explosion-proof valve seat 1202 is engaged with the vent seat 1203, and the vent seat 1203 has pressure relief holes equidistantly spaced on it. The top of 203 is conical, and L-shaped frames are equidistantly arranged on its side wall to support the pressure relief valve 1204. The top of the conical part and the top of the L-shaped frame of the vent seat 1203 abut against the bottom of the pressure relief valve 1204. A return spring 1205 is provided between the vent seat 1203 and the pressure relief valve 1204. A safety contact edge 1206 is provided below the pressure relief valve 1204 along the side wall of the hole of the positioning top cover 10. The contact surface of the safety contact edge 1206 faces the side wall of the vent seat 1203. The safety contact edge 1206 is electrically connected to the wiring terminal 11.

[0042] Referring to the attached diagrams in the instruction manual Figures 1-6As shown, during normal use, the lower positioning seat 2, positioning support 5, and cell limiting frame 6 together fix the lithium battery body 7. The bottom gasket 4 acts as an insulating buffer to prevent short circuits and vibration damage between the battery cell and the main body 1. The sealing ring at the connection between the positioning top cover 10 and the main body 1, and the annular sealing ring 9 on the inner wall of the auxiliary positioning frame 8 form a double seal to prevent electrolyte leakage and the intrusion of external water, oxygen, and impurities. The heat dissipation fins 3 on the outer wall of the main body 1 quickly dissipate the heat generated by the lithium battery body 7 during operation to avoid overheating and thermal runaway. The wiring terminal 11 stably achieves electrical connection and is reliably sealed to ensure power supply safety.

[0043] When the lithium battery body 7 experiences thermal runaway and generates a large amount of high-temperature and high-pressure gas, the gas diffuses through the flow hole of the auxiliary positioning frame 8. After the gas pressure reaches the preset threshold, the high-pressure gas exerts an upward thrust on the vent seat 1203. This thrust overcomes the preload of the reset spring 1205 and pushes the vent seat 1203 upward. At this time, the pressure relief valve 1204 is lifted by the vent seat 1203 to create a gap. The high-temperature and high-pressure gas inside the shell is quickly discharged through the pressure relief hole on the vent seat 1203 to achieve pressure relief and reduce pressure, thereby preventing the internal pressure of the shell from continuously rising beyond the material strength limit and preventing the shell from rupturing and exploding.

[0044] During the depressurization process, the safety contact 1206 acts as a limit, the vent seat 1203 moves upward, and the safety contact 1206 contacts the vent seat 1203, causing the safety contact 1206 to send an electrical signal to the terminal 11 to stop the power supply to the terminal 11.

[0045] After the air pressure drops to the safe threshold, the reset spring 1205 pushes the vent seat 1203 back to the explosion-proof valve seat 1202 to reset, close the pressure relief channel, restore the sealing protection, and prevent external impurities from entering. The entire process requires no manual operation, realizing automatic explosion-proof protection and eliminating secondary safety hazards. When maintenance is required, the positioning top cover 10 can be opened by removing the bolts, and after inspecting the lithium battery body 7 and each protective component, it can be closed and fixed again to restore use, ensuring the effectiveness of long-term safety protection.

[0046] Working principle: When using this lithium battery sealed explosion-proof housing, during normal operation, the lower positioning seat 2, positioning support 5, and cell limiting frame 6 work together to fix the lithium battery body 7. The bottom gasket 4 plays an insulating and buffering role, preventing short circuits and vibration damage between the cell and the housing body 1. The sealing ring at the connection between the positioning top cover 10 and the housing body 1, and the annular sealing ring 9 on the inner wall of the auxiliary positioning frame 8 form a double seal to prevent electrolyte leakage and external impurities from entering. The heat dissipation fins 3 quickly dissipate the working heat of the lithium battery body 7 to avoid overheating. The wiring terminals 11 provide stable sealed power supply to ensure normal operation.

[0047] When the lithium battery body 7 experiences thermal runaway, it generates high-temperature and high-pressure gas. The gas diffuses through the flow hole of the auxiliary positioning frame 8. When the gas pressure reaches the preset threshold, it pushes the vent seat 1203 to move upward, overcomes the pre-tightening force of the reset spring 1205, and lifts the pressure relief valve 1204 to form a gap. The high-temperature and high-pressure gas is discharged through the pressure relief hole of the vent seat 1203, thereby achieving pressure relief and preventing the shell from breaking.

[0048] During depressurization, the vent seat 1203 moves upward to contact the safety contact 1206. The safety contact 1206 sends a signal to stop the power supply to the terminal 11. After the air pressure drops to the safety threshold, the reset spring 1205 pushes the vent seat 1203 back to the explosion-proof valve seat 1202 to reset, closing the depressurization channel and restoring the seal. When maintenance is required, the positioning top cover 10 can be opened by removing the bolts, and after inspection, it can be closed and fixed again to ensure long-term protection effectiveness and increase overall practicality.

[0049] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A sealed explosion-proof housing for a lithium battery, comprising: The main body of the housing (1) is the main housing structure for accommodating the lithium battery. The top opening of the main body of the housing (1) is covered by a positioning top cover (10), and the edges of the main body of the housing (1) and the positioning top cover (10) are detachably and sealed by bolts. The features are as follows: a cell lower positioning seat (2) is provided on the bottom inner wall of the main body (1), and a bottom pad (4) is embedded in the cell lower positioning seat (2). A positioning support (5) is symmetrically provided on the top of the cell lower positioning seat (2), and the positioning support (5) is above the bottom pad (4). A lithium battery body (7) is embedded on the top of the cell lower positioning seat (2). The inner wall of the housing body (1) is provided with an auxiliary positioning frame (8) at the top, and an annular sealing ring (9) is embedded in the inner wall of the auxiliary positioning frame (8). The auxiliary positioning frame (8) is set on the top of the lithium battery body (7), and the top of the lithium battery body (7) abuts against the inner side of the annular sealing ring (9). The auxiliary positioning frame (8) is provided with flow holes for gas flow at equal intervals. The top of the positioning top cover (10) is embedded with a wiring terminal (11) and an explosion-proof valve assembly (12), and the explosion-proof valve assembly (12) surrounds the periphery of the wiring terminal (11).

2. The sealed explosion-proof housing for lithium batteries according to claim 1, characterized in that: The outer wall of the main body (1) is provided with heat dissipation fins (3) at equal intervals, and the heat dissipation fins (3) are evenly arranged along the bottom outer edge of the main body (1) and fixed to the main body (1) by laser welding.

3. The sealed explosion-proof housing for lithium batteries according to claim 1, characterized in that: The top of the positioning support (5) is fitted with a cell limiting frame (6), and the cell limiting frame (6) is engaged with the side wall of the lithium battery body (7). The two sides of the lithium battery body (7) are respectively secured between the two positioning supports (5) by the cell limiting frame (6).

4. The lithium battery sealed explosion-proof housing according to claim 1, characterized in that: The top of the positioning cover (10) is provided with a hole that is compatible with the installation of the explosion-proof valve assembly (12), and a sealing ring is provided at the connection between the positioning cover (10) and the housing body (1).

5. The sealed explosion-proof housing for lithium batteries according to claim 1, characterized in that: The explosion-proof valve assembly (12) includes an explosion-proof valve stem (1201), an explosion-proof valve seat (1202), a vent seat (1203), a pressure relief valve disc (1204), a return spring (1205), and a safety contact edge (1206). The explosion-proof valve stem (1201) is installed at the top of the hole in the positioning top cover (10), the explosion-proof valve seat (1202) is installed at the bottom of the hole in the positioning top cover (10), and the explosion-proof valve stem (1201) is installed vertically at the top of the explosion-proof valve seat (1202).

6. The lithium battery sealed explosion-proof housing according to claim 5, characterized in that: The top of the explosion-proof valve seat (1202) is engaged with a vent seat (1203), and the vent seat (1203) has pressure relief holes at equal intervals. The top of the vent seat (1203) has a conical structure, and L-shaped frames are provided at equal intervals on its side wall to support the pressure relief valve disc (1204).

7. The lithium battery sealed explosion-proof housing according to claim 6, characterized in that: The top of the cone of the vent seat (1203) and the top of the L-shaped frame are both in contact with the bottom of the pressure relief valve (1204). A reset spring (1205) is provided between the vent seat (1203) and the pressure relief valve (1204). A safety contact (1206) is provided below the pressure relief valve (1204) along the side wall of the hole of the positioning top cover (10). The contact surface of the safety contact (1206) faces the side wall of the vent seat (1203). The safety contact (1206) is electrically connected to the terminal block (11).

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