Battery structure integrating explosion prevention and pressure balance, battery pack and electric automobile

Abstract

The utility model discloses a battery structure integrating anti-explosion and pressure balancing, a battery pack and an electric automobile, and relates to the technical field of new energy, the battery structure comprises a loading assembly, a battery module, an anti-explosion assembly and a pressure balancing assembly used for ensuring that the internal and external pressures of the loading assembly are balanced, and the battery module is arranged in the loading assembly. The anti-explosion assembly and the pressure balancing assembly are both arranged on the loading assembly and communicate with the interior of the loading assembly. The battery structure ensures balance of pressure inside and outside the battery pack, so that the battery pack is in a safer working interval, and the service life of a battery system is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of new energy, and in particular to a battery structure, a battery pack and an electric vehicle with integrated explosion-proof and pressure-equalizing functions. Background Art

[0002] The battery cell is the energy storage element of the lithium battery. When the lithium battery is in use, abnormal gas will be generated inside the shell due to factors such as the charger, as well as the internal chemical reaction of the lithium battery, causing the internal pressure of the lithium battery shell to be too high. If the internal pressure of the shell continues to increase, the internal pressure of the lithium battery will be too high, resulting in a lithium battery explosion accident.

[0003] Lithium-ion battery packs are composed of multiple cells connected in series. During daily use, the charging and discharging of the battery pack gradually leads to imbalances between the battery cells, resulting in a decline in battery performance and consistency. This is manifested as voltage differences between the cells. Imbalance occurs when one or more cells in a series connection charge faster or slower than the others.

[0004] Traditional battery systems can vent gas when the battery cells are in thermal runaway state, but lack the battery system pressure equalization function. There are many alternating hot and cold working conditions inside the battery system, and the air pressure changes greatly, resulting in poor battery safety. Utility Model Content

[0005] Based on the technical problems existing in the background technology, the utility model proposes a battery structure, a battery pack and an electric vehicle with integrated explosion-proof and pressure-balanced functions, which ensures the pressure balance inside and outside the battery pack, allows the battery pack to operate in a safer range, and improves the life of the battery system.

[0006] The utility model proposes an integrated explosion-proof and pressure-equalizing battery structure, which includes a loading assembly, a battery module, an explosion-proof assembly, and a pressure-equalizing assembly for ensuring pressure balance inside and outside the loading assembly. The battery module is arranged in the loading assembly, and the explosion-proof assembly and the pressure-equalizing assembly are both arranged on the loading assembly and communicated with the interior of the loading assembly.

[0007] Furthermore, the battery structure also includes a baffle, the explosion-proof component and the pressure equalization component are arranged adjacent to each other, the baffle covers the explosion-proof component and the pressure equalization component and is fixedly connected to the loading component

[0008] Furthermore, the pressure equalization assembly includes a main body base and a protective shell connected to the main body base, the main body base is provided with a polymer waterproof and breathable membrane, the main body base is provided with a secondary spring, a shaft sleeve and a valve that opens one-way toward the main body base, the valve is provided in the shaft sleeve and abuts against a boss provided on the shaft sleeve, one end of the secondary spring abuts against the bottom of the valve and the other end abuts against the bottom wall of the main body base, the polymer waterproof and breathable membrane is provided above the valve, and a gas channel is provided between the main body base and the protective shell;

[0009] When the external pressure of the loading assembly is greater than the internal pressure, the external gas enters the channel above the valve through the polymer waterproof and breathable membrane. The valve moves downward through the compression of the secondary spring and forms a lower channel with the shaft sleeve. The external gas enters the loading assembly through the lower channel, completing the air intake of the loading assembly.

[0010] When the external pressure of the loading assembly is lower than the internal pressure, the internal gas of the loading assembly reaches the position below the valve through the gas channel of the main base and the protective shell, and opens one-way to the main base through the valve. The internal gas passes through the inside of the sleeve and through the polymer waterproof and breathable membrane to be discharged from the main base, completing the exhaust of the loading assembly.

[0011] Furthermore, a pressure plate, a breathable membrane gasket and an upper fixed base are also provided in the main body base. Along the pointing direction of the main body base toward the protective shell, the pressure plate, the breathable membrane gasket and the upper fixed base are arranged in sequence. The breathable membrane gasket is arranged between the pressure plate and the upper fixed base to form a channel for gas to pass through. The upper fixed base is arranged above the polymer waterproof breathable membrane, and the upper fixed base is provided with an upper hole connected to the polymer waterproof breathable membrane for gas to pass through.

[0012] Furthermore, the loading assembly includes an upper cover and a lower box body, and the space formed by the upper cover and the lower box body is used to load the battery module.

[0013] Furthermore, a sealing gasket is provided at the connection between the upper cover and the lower box body;

[0014] A battery pack adopts the battery structure described above;

[0015] An electric vehicle comprises a vehicle body and a battery pack arranged on the vehicle body, wherein the battery pack is the battery pack described above.

[0016] The advantages of an integrated explosion-proof and pressure-equalizing battery structure, battery pack, and electric vehicle provided by the present invention are that: the combined use of explosion-proof components and pressure-equalizing components, on the one hand, performs exhaust and pressure relief when thermal runaway occurs in the battery cell, and on the other hand, regulates the pressure inside and outside the battery pack when thermal runaway does not occur in the battery cell, thereby ensuring the safety requirement of pressure equalization inside and outside the battery pack; it is a structure that meets the pressure equalization (intake and exhaust) of the battery system in a non-thermal runaway state and the intake or exhaust function in a thermal runaway state; the battery structure meets the requirements of pressure equalization inside and outside the battery pack and improves the safety of the battery system, allowing the battery pack to operate in a safer range and prolonging the life of the battery system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural diagram of the utility model;

[0018] Figure 2 for Figure 1 A magnified view of the local structure;

[0019] Figure 3 It is a structural diagram of the pressure equalization component;

[0020] Figure 4 This is a schematic diagram of the structure of the air intake of the pressure equalization component;

[0021] Figure 5 Schematic diagram of the structure for exhausting the pressure equalization component;

[0022] Among them, 1-loading assembly, 2-battery module, 3-explosion-proof assembly, 4-pressure equalization assembly, 5-baffle, 6-spacer, 11-upper cover, 12-lower box, 13-sealing gasket, 41-main base, 42-protective shell, 43-polymer waterproof and breathable membrane, 44-secondary spring, 45-sleeve, 46-valve, 47-pressure plate, 48-breathable membrane gasket, 49-upper fixed base. DETAILED DESCRIPTION

[0023] The following describes the technical solution of the present invention in detail through specific embodiments. Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0024] like Figure 1 and 5As shown, the integrated explosion-proof and pressure-equalizing battery structure proposed in the present invention includes a loading assembly 1, a battery module 2, an explosion-proof assembly 3 and a pressure-equalizing assembly 4 for ensuring pressure balance inside and outside the loading assembly 1. The battery module 2 is arranged in the loading assembly 1, and the explosion-proof assembly 3 and the pressure-equalizing assembly 4 are both arranged on the loading assembly 1 and communicate with the interior of the loading assembly 1.

[0025] The explosion-proof component 3 can adopt an explosion-proof valve to vent and relieve pressure when the battery cell has thermal runaway. The pressure equalization component 4 adopts a pressure equalization valve to vent when the battery cell has thermal runaway, and to adjust the pressure inside and outside the battery pack when the battery cell has not thermal runaway, thereby ensuring the safety requirement of pressure balance inside and outside the battery pack. It is a structure that meets the pressure balance (intake and exhaust) of the battery system in the non-thermal runaway state and the intake or exhaust function in the thermal runaway state. Therefore, the battery structure of this embodiment can meet the pressure balance inside and outside the battery pack and improve the safety of the battery system, so that the battery pack can be in a safer working range and the battery system life can be improved.

[0026] In this embodiment, the loading assembly 1 includes an upper cover 11 and a lower case 12. The space formed by the upper cover 11 and the lower case 12 is used to load the battery module 2. A sealing gasket 13 is provided at the connection between the upper cover 11 and the lower case 12 to seal the connection between the upper cover 11 and the lower case 12, thereby placing the battery module 2 in a relatively sealed environment. The upper cover 11 and the lower case 12 can also be connected by a snap fastener, supplementing other connection methods to facilitate the removal of the upper cover 11 and the lower case 12.

[0027] In this embodiment, the battery structure also includes a baffle 5. The explosion-proof component 3 and the pressure equalizing component 4 are arranged adjacent to each other. The baffle 5 covers the explosion-proof component 3 and the pressure equalizing component 4 and is fixedly connected to the loading component 1. The baffle 5 is used to cover the explosion-proof component 3 and the pressure equalizing component 4. At the same time, according to the opening position reserved by the baffle 5, the high-temperature gas passing through the explosion-proof component 3 and the pressure equalizing component 4 can be directed. In addition, a spacer 6 is provided on the baffle 5. The spacer 6 is provided in the gap between the explosion-proof component 3 and the pressure equalizing component 4 of the baffle 5. The provision of the spacer 6 allows the explosion-proof component 3 and the pressure equalizing component 4 to work independently of each other. When used in conjunction with the baffle 5, the high-temperature gas can be directed out to prevent the high-temperature gas ejected in the thermal runaway state of the battery cell from affecting other components such as the connectors and wiring harnesses around the battery pack. This design meets the safety requirements of thermal runaway and battery pack air pressure balance.

[0028] The battery module 2 is obtained by bonding multiple battery cells together. The battery module 2 is placed in the loading assembly 1 to form a battery pack. When the battery cell experiences thermal runaway or the valve inside the battery cell is open, the internal pressure of the battery pack gradually increases, and the high-temperature gas compresses the explosion-proof assembly 3 and the pressure equalizing assembly 4. When the pressure reaches the critical bursting pressure set by the explosion-proof assembly 3 and the pressure equalizing assembly 4, the compressed explosion-proof assembly 3 and the pressure equalizing assembly 4 begin to exhaust to the outside to ensure the pressure balance inside and outside the battery pack and the safety of the battery pack. The explosion-proof assembly 3 can use an existing explosion-proof valve, which will not be elaborated here.

[0029] When the battery cell does not experience thermal runaway, under conditions such as temperature and air pressure alternation, such as high and low temperature shock conditions or altitude alternation and severe weather conditions, the pressure equalization component 4 will ventilate through the air intake unit or exhaust through the exhaust unit according to the pressure difference between the inside and outside of the battery pack to ensure internal and external pressure balance, such as Figure 3 As shown, the pressure equalizing assembly 4 includes a main body base 41 and a protective shell 42 connected to the main body base 41, a polymer waterproof and breathable membrane 43 is provided in the main body base 41, a secondary spring 44, a sleeve 45 and a valve 46 with a one-way opening toward the main body base 41 are provided in the main body base 41, the valve 46 is provided in the sleeve 45 and abuts against a boss provided on the sleeve 45, one end of the secondary spring 44 abuts against the bottom of the valve 46, and the other end abuts against the bottom wall of the main body base 41, the polymer waterproof and breathable membrane 43 is provided above the valve 46, and a gas channel is provided between the main body base 41 and the protective shell 42. In addition, a pressure plate 47, a breathable membrane gasket 48 and an upper fixed base 49 are also provided in the main base 41. Along the direction of the main base 41 toward the protective shell 42, the pressure plate 47, the breathable membrane gasket 48 and the upper fixed base 49 are arranged in sequence. The breathable membrane gasket 48 is arranged between the pressure plate 47 and the upper fixed base 49 to form a channel for gas to pass through. The upper fixed base 49 is arranged above the polymer waterproof breathable membrane 43, and an upper hole connected to the polymer waterproof breathable membrane 43 is opened on the upper fixed base 49 for gas to pass through.

[0030] The provision of the breathable membrane gasket 48 facilitates the setting of a gas channel between the pressure plate 47 and the upper fixed base 49. The provision of the polymer waterproof breathable membrane 43 prevents external gas from carrying water vapor into the loading assembly 1, thereby improving the air intake safety of the loading assembly 1.

[0031] It can be understood that the valve 46 abuts against the boss set on the sleeve 45. Under normal circumstances, the valve 46 can stably abut against the boss through the elastic action of the auxiliary spring 44. At this time, there is no connecting channel between the valve 46 and the sleeve 45. However, when the auxiliary spring 44 is compressed, the valve 46 moves downward. At this time, the valve 46 no longer abuts against the boss, and there is a gap space between the valve 46 and the boss. Therefore, the valve 46 and the sleeve 45 form a channel for gas to pass through the gap space. Therefore, when external gas is introduced, the valve 46 can move downward to form a connecting gas channel between the main base 41 and the protective shell 42, thereby realizing the introduction of external gas.

[0032] In addition, since the valve 46 is one-way open to the main body base 41, under normal circumstances, the valve 46 is in a closed state. When the internal gas in the loading component 1 reaches the valve 46 and the air pressure exceeds the pressure at which the valve 46 begins to open, the one-way opening of the valve 46 opens, thereby forming a connected gas channel between the main body base 41 and the protective shell 42, and the external gas can be discharged through the gas channel.

[0033] The above-mentioned setting of the valve 46 (abutting against the boss and setting a one-way opening) enables the pressure equalization component 4 to realize air intake and exhaust through one structure. Therefore, although the air intake and exhaust of the pressure equalization component 4 rely on the same structure, the air intake and exhaust are two processes under opposite conditions. Therefore, the air intake and exhaust are two independent processes that do not interfere with each other, reducing the risk of failure.

[0034] like Figure 4 The air intake process of the pressure equalization component 4 shown is as follows: when the external pressure of the loading component 1 is greater than the internal pressure (high temperature and high altitude, etc.), the external gas (orange line) enters the upper part of the polymer waterproof breathable membrane 43 through multiple gas channels of the upper fixed base 49, the pressure plate 47 and the breathable membrane gasket 48, and enters the channel above the valve 46 through the polymer waterproof breathable membrane 43. At this time, the pressure is greater than the pressure of the auxiliary spring 44 below the valve 46, the auxiliary spring 44 is compressed, and the valve 46 moves downward. The external gas enters the protective shell 42 through the channel formed by the valve 46 and the shaft sleeve 45. Multiple gas channels are provided in the protective shell 42 and the main base 41. The external gas enters the loading component 1 to ensure that the air pressure inside and outside the loading component 1 is balanced.

[0035] like Figure 5The exhaust process of the pressure equalization component 4 shown is as follows: when the external pressure of the loading component 1 is lower than the internal pressure (overheating or battery cell out of control and other working conditions), the internal gas of the loading component 1 (orange line) reaches the position below the valve 46 through the gas channel of the main base 41 and the protective shell 42. The air pressure of the internal gas reaches the starting pressure of the valve 46, and the valve 46 opens one-way toward the main base 41. The internal gas passes through the inside of the shaft sleeve 45 through the polymer waterproof and breathable membrane 43, and is discharged through the gas channel of the upper fixed base 49, the pressure plate 47 and the breathable membrane gasket 48, completing the exhaust of the loading component 1.

[0036] As a preferred embodiment, a battery pack adopts the battery structure as described above.

[0037] As another preferred embodiment, an electric vehicle includes a vehicle body and a battery pack disposed on the vehicle body, wherein the battery pack is the battery pack described above.

[0038] The above is only a preferred specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with the technical field within the technical scope disclosed by the present invention can make equivalent replacements or changes based on the technical solution and utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. Integrated explosion-proof and pressure-equalizing battery structure, characterized in that: The invention comprises a loading assembly (1), a battery module (2), an explosion-proof assembly (3), and a pressure equalization assembly (4) for ensuring pressure balance inside and outside the loading assembly (1); the battery module (2) is arranged in the loading assembly (1); the explosion-proof assembly (3) and the pressure equalization assembly (4) are both arranged on the loading assembly (1) and communicated with the interior of the loading assembly (1); The pressure equalizing assembly (4) includes a main body base (41) and a protective shell (42) connected to the main body base (41), a polymer waterproof breathable membrane (43) is provided in the main body base (41), a secondary spring (44), a shaft sleeve (45) and a valve (46) with a one-way opening toward the main body base (41) are provided in the main body base (41), the valve (46) is provided in the shaft sleeve (45) and abuts against a boss provided on the shaft sleeve (45), one end of the secondary spring (44) abuts against the bottom of the valve (46) and the other end abuts against the bottom wall of the main body base (41), the polymer waterproof breathable membrane (43) is provided above the valve (46), and a gas channel is provided between the main body base (41) and the protective shell (42); When the external pressure of the loading assembly (1) is greater than the internal pressure, the external gas enters the upper channel of the valve (46) through the polymer waterproof and breathable membrane (43), and the valve (46) moves downward through the compression of the auxiliary spring (44) and forms a lower channel with the shaft sleeve (45), and the external gas enters the loading assembly (1) through the lower channel, completing the air intake of the loading assembly (1); When the external pressure of the loading assembly (1) is lower than the internal pressure, the internal gas of the loading assembly (1) reaches the position below the valve (46) through the gas passage of the main body base (41) and the protective shell (42), and is opened one-way toward the main body base (41) through the valve (46). The internal gas passes through the inside of the shaft sleeve (45) and passes through the polymer waterproof and breathable membrane (43) to be discharged from the main body base (41), thereby completing the exhaust of the loading assembly (1).

2. The integrated explosion-proof and pressure-equalizing battery structure according to claim 1, characterized in that: The battery structure further includes a baffle (5), the explosion-proof component (3) and the pressure equalization component (4) are arranged adjacent to each other, and the baffle (5) covers the explosion-proof component (3) and the pressure equalization component (4) and is fixedly connected to the loading component (1).

3. The integrated explosion-proof and pressure-equalizing battery structure according to claim 2, characterized in that: A spacer (6) is provided on the baffle (5), and the spacer (6) is provided in the gap between the explosion-proof component (3) and the pressure equalization component (4) of the baffle (5).

4. The integrated explosion-proof and pressure-equalizing battery structure according to claim 1, characterized in that: The main body base (41) is further provided with a pressure plate (47), a breathable membrane gasket (48) and an upper fixed base (49). The pressure plate (47), the breathable membrane gasket (48) and the upper fixed base (49) are arranged in sequence along the direction from the main body base (41) to the protective shell (42). The breathable membrane gasket (48) is arranged between the pressure plate (47) and the upper fixed base (49) to form a channel for gas to pass through. The upper fixed base (49) is arranged above the polymer waterproof breathable membrane (43), and an upper hole is opened on the upper fixed base (49) to communicate with the polymer waterproof breathable membrane (43) for gas to pass through.

5. The integrated explosion-proof and pressure-equalizing battery structure according to claim 1, characterized in that: The loading assembly (1) comprises an upper cover (11) and a lower box body (12); the space formed by the upper cover (11) and the lower box body (12) is used for loading the battery module (2).

6. The integrated explosion-proof and pressure-equalizing battery structure according to claim 5, characterized in that: A sealing gasket (13) is provided at the connection between the upper cover (11) and the lower box body (12).

7. A battery pack, characterized in that: The battery pack adopts the battery structure as described in any one of claims 1 to 6.

8. An electric vehicle, characterized in that: The vehicle comprises a vehicle body and a battery pack arranged on the vehicle body, wherein the battery pack is the battery pack as claimed in claim 7.

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