Novel explosion-proof device for power battery

Abstract

The utility model discloses a novel explosion-proof device for a power battery. The novel explosion-proof device comprises a hollow screw, a valve, a spring, an exhaust column, a main body, a bracket, a breathable film, a magnetic piece and a top cover, by adding the valve structure and improving the assembly structure between the support and the exhaust column, the moisture-proof function is added, external gas with moisture is effectively prevented from entering the box body, meanwhile, the structure is optimized, stability is improved, badness is reduced, and manufacturing cost is saved.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of explosion-proof devices, specifically to a kind of new explosion-proof device for power battery. BACKGROUND

[0002] Power battery is the core component of new energy vehicles such as electric vehicles, which stores chemical energy by converting electrical energy through chemical reaction, and releases electrical energy by converting chemical energy when needed to provide power for vehicles. Through the control system to drive the electric motor to rotate the wheels, it can not only be used in electric vehicles, but also be applied to energy storage systems. By storing electrical energy, power battery can release supply to households, industries and even power grid when needed, improving energy utilization efficiency and balancing the difference between energy supply and demand.

[0003] Power battery explosion-proof valve is a kind of key safety device, which is used to prevent battery explosion under abnormal conditions. Its working principle is mainly to prevent battery explosion by releasing internal pressure when the internal pressure of the battery rises to a certain extent; the explosion-proof valve functions to allow the free flow of gas inside and outside the battery pack box, achieving internal and external air pressure balance. When the internal gas pressure of the battery pack box is greater than the ambient pressure, the gas is discharged outward; otherwise, the external gas enters the box, thereby maintaining the air pressure balance; when the battery is in thermal runaway, the internal chemical reaction will produce a large amount of gas, causing the pressure to rise sharply. The explosion-proof valve is designed on the battery shell, which will be opened when the pressure exceeds the set value, releasing the internal pressure to prevent the battery from exploding.

[0004] The existing technology structure has certain defects, which cannot effectively block the gas with moisture from outside, and the assembly between the exhaust column and the support may cause the top cover assembly and the main body to be no longer on the same center, resulting in poor protection risk, insufficient stability, increased manufacturing risk and material cost. UTILITY MODEL CONTENTS

[0005] In view of the problems existing in the prior art, the utility model provides a new explosion-proof device for power battery, which adds a valve structure and improves the assembly structure between the support and the exhaust column, thereby adding a moisture-blocking function, effectively reducing the entry of gas with moisture from outside into the box, optimizing the structure, increasing the stability, reducing the defects and saving the manufacturing cost.

[0006] The technical scheme of the utility model is: a new explosion-proof device for power battery, comprising a hollow screw, a valve, a spring, an exhaust column, a main body, a support, a breathable film, a magnetic piece and a top cover.

[0007] The top cover back is provided with an annular convex ring, the bottom surface of the annular convex ring is uniformly provided with a plurality of arc-shaped ribs, and a first gas passage is formed between adjacent arc-shaped ribs;

[0008] The magnetic attraction piece is pasted in the annular convex ring on the back of the top cover to form a top cover assembly;

[0009] The front center part of the support is recessed with a clamping groove, a plurality of second gas passages are evenly arranged on the support body in the radial direction along the circumference of the clamping groove, and the center of the support is provided with a hollow stud;

[0010] The air permeable film is pasted in the clamping groove on the front of the support to form a support assembly;

[0011] The annular convex ring on the back of the top cover assembly can be pressed in the clamping groove on the front of the support assembly in interference fit, and the arc-shaped convex rib on the back of the top cover assembly can press the air permeable film after the top cover assembly is pressed into place;

[0012] The center of the main body is provided with a hollow stud on the back of the support assembly, which can be inserted into the center hole of the main body;

[0013] The inner surface of the exhaust column facing one end of the main body is provided with a first internal thread, and the exhaust column facing one end of the main body can be inserted into the center hole of the main body and threadedly connected with the hollow stud on the back of the support assembly;

[0014] The inner surface of the exhaust column away from the main body is provided with a step surface, the valve is prevented in the exhaust column, and the edge of the valve is placed on the step surface;

[0015] The inner surface of the exhaust column away from the main body is further provided with a second internal thread, the spring is sleeved on the outer surface of the exhaust column, and the hollow screw is screwed with the second internal thread in the exhaust column after pressing the spring, fixing the inner valve.

[0016] Further, the protective sleeve is sleeved on the outside of the hollow screw, spring and exhaust column, and is pressed in the clamping groove arranged on the back of the main body in interference fit.

[0017] Further, the outer sealing ring and the inner sealing ring are respectively embedded in the front and back of the main body.

[0018] The beneficial effects of the utility model are:

[0019] 1. Add valve; increase the product moisture-proof function, can reduce the possibility of battery pack box body electrical short circuit fault.

[0020] 2. Reduce the risk of product failure that may exist in the existing structure. The existing assembly mode between the exhaust column and the support is easy to produce the top cover assembly and the main body no longer on the same center, and the top cover assembly is easy to shake under external force. The optimized structure changes the support to external thread and the exhaust column to internal thread. The top cover assembly and the exhaust column are closely matched by threads. When subjected to external force again, the exhaust column will be supported, enhancing stability and protection performance. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 It is the overall explosion diagram of the new explosion-proof device for power battery;

[0022] Figure 2 It is a structure diagram of attaching the magnetic attraction piece to the top cover;

[0023] Figure 3 It is a structure diagram of attaching the breathable film to the corresponding card slot of the support;

[0024] Figure 4 It is a structure diagram of installing the inner sealing ring into the main body card slot;

[0025] Figure 5 It is a diagram of pressing the prefabricated support assembly and the top cover assembly together through interference fit;

[0026] Figure 6 It is a back surface diagram of the upper cover;

[0027] Figure 7 It is a diagram of pressing the installed support assembly into the main body and pressing the inner sealing ring on the main body; using the exhaust column to screw into the thread exposed on the back surface of the support, fixing the main body and the support assembly together;

[0028] Figure 8 It is a diagram of installing the valve into the exhaust column, simultaneously using the spring to cover the exhaust column, and then using the M8 hollow screw to press the spring and the thread of the exhaust column together. Then, the protective sleeve is pressed into the corresponding card slot of the main body through interference fit. Finally, the outer sealing ring is installed into the corresponding card slot of the main body, and the assembly is completed.

[0029] Figure 9 It is a diagram of normal pressure under the closed state of the valve;

[0030] Figure 10 It is a diagram of normal pressure under the open state of the valve;

[0031] Figure 11 It is a diagram of the open state of the explosion-proof valve when the pressure is too large.

[0032] In the figure: 1 is outer sealing ring, 2 is protective sleeve, 3 is hollow screw, 4 is valve, 5 is spring, 6 is exhaust column, 7 is main body, 8 is inner sealing ring, 9 is support, 10 is breathable membrane, 11 is magnetic sheet, 12 is top cover, 13 is upper cover assembly, 14 support assembly. DETAILED DESCRIPTION

[0033] The utility model makes further explanation in combination with the drawings.

[0034] As Figures 1-11 shown, a new type of explosion-proof device for power battery, including outer sealing ring 1, protective sleeve 2, hollow screw 3, valve 4, spring 5, exhaust column 6, main body 7, inner sealing ring 8, support 9, breathable membrane 10, magnetic sheet 11 and top cover 12.

[0035] As Figure 2 shown, the top cover 12 back is provided with annular convex ring, the bottom surface of annular convex ring is evenly provided with multiple arc-shaped ribs, and first gas passage is formed between adjacent arc-shaped ribs. The magnetic sheet 11 is pasted in the annular convex ring of the back of the top cover 12, and forms the upper cover assembly 13.

[0036] As Figure 3 shown, the support 9 front center part recess has the clamping groove, and a plurality of second gas passages are evenly radially arranged on the support main body of the clamping groove. The support 9 center hole is provided with a hollow screw column on the back center of the support 9. The breathable membrane 10 is pasted in the clamping groove of the front of the support 9, and forms the support assembly 14.

[0037] As Figure 5 , 6 shown, the annular convex ring of the back of the upper cover assembly 13 can be pressed in the clamping groove of the front of the support assembly 14 by interference fit, and the arc-shaped ribs of the back of the upper cover assembly 13 can press the breathable membrane 10 after the upper cover assembly 13 is pressed in place.

[0038] As Figure 4 shown, the outer sealing ring 1 and the inner sealing ring 8 are respectively embedded in the front and back of the main body 7, the main body 7 center hole is provided with a hollow screw column, and the hollow screw column of the back of the support assembly 14 can be inserted into the center hole of the main body 7.

[0039] As Figure 7 shown, the inner surface of one end of the exhaust column 6 facing the main body 7 is processed with first internal thread, and the one end of the exhaust column 6 facing the main body 7 can be inserted into the center hole of the main body 7 and threadedly connected with the hollow screw column on the back of the support assembly 14.

[0040] As Figure 8As shown, the inner surface of the exhaust column 6 at the end away from the main body 7 is provided with a stepped surface, the valve 4 is prevented in the exhaust column 6 and the edge of the valve 4 is placed on the stepped surface. The inner surface of the exhaust column 6 at the end away from the main body 7 is also provided with a second internal thread, the spring 5 is sleeved on the outer surface of the exhaust column 6, and the hollow screw 3 is screwed together with the second internal thread in the exhaust column 6 after pressing the spring 5, to fix the inner valve 4. The protective sleeve 2 is sleeved on the outer side of the hollow screw 3, the spring 5 and the exhaust column 6, and is pressed in the clamping groove correspondingly provided on the back of the main body 7 in an interference fit.

[0041] Function implementation process and purpose:

[0042] 1. Under the premise that the internal pressure of the battery pack box body is less than the set burst value of the explosion-proof valve, when the pressure inside the valve is less than the preset pressure, the valve cannot be opened to prevent external air from entering and reduce the entry of gas containing moisture into the cavity (such as Figure 9 ); When the pressure inside the valve is greater than the preset pressure, it will flow normally, which is the same as the working principle of the traditional waterproof air permeable valve (such as Figure 10 ): The gas inside and outside the battery pack box body flows freely through the waterproof air permeable membrane built in the valve body, and the gas flows from the side with high pressure to the side with low pressure, that is, when the internal pressure of the battery pack box body is greater than the external pressure of the box body, the gas is discharged outward, and when the internal pressure of the battery pack box body is less than the external pressure of the box body, the gas will enter the inner cavity, so as to realize the balance of internal and external air pressure. Such as Figure 10 The arrow A indicates the direction of gas flow.

[0043] 2. When the internal pressure of the battery pack box body is greater than or equal to the set burst value of the explosion-proof valve, it is in the working state of the explosion-proof valve, at this time the internal pressure pushes open the bracket (such as Figure 11 indicated by arrow B), and the gas will pass through the unobstructed passage and be directly connected to the outside (such as Figure 11 indicated by arrow C), to realize rapid discharge of gas, thereby rapidly reducing the internal pressure of the box body and preventing the battery pack from exploding. The explosion-proof device plays a role in explosion-proof in this state.

[0044] The above only describes preferred embodiments of the present application, and it should be pointed out that for ordinary skilled persons in the technical field, without departing from the principles of the present application, a number of improvements and refinements can be made, which should also be considered as the protection range of the present application.

Claims

1. A new type of explosion-proof device for power battery, characterized in that: It comprises a hollow screw (3), a valve (4), a spring (5), an exhaust column (6), a main body (7), a bracket (9), a breathable membrane (10), a magnetic sheet (11) and a top cover (12); The back surface of the top cover (12) is provided with an annular protruding ring, and the bottom surface of the annular protruding ring is uniformly provided with a plurality of arc-shaped protruding ribs, and a first gas passage is formed between adjacent arc-shaped protruding ribs. The magnetic sheet (11) is pasted in the annular protruding ring on the back surface of the top cover (12), forming an upper cover assembly (13). The front surface of the bracket (9) is recessed at the center part, and a plurality of second gas passages are uniformly arranged on the bracket main body in the circumferential direction along the radial direction; the bracket (9) is provided with a hollow stud at the center. The breathable membrane (10) is pasted in the clamping groove on the front surface of the bracket (9), forming a bracket assembly (14). The annular protruding ring on the back surface of the upper cover assembly (13) can be pressed into the clamping groove on the front surface of the bracket assembly (14) by interference fit, and after the upper cover assembly (13) is pressed into place, the arc-shaped protruding ribs on the back surface of the upper cover assembly (13) can press the breathable membrane (10); The main body (7) is provided with a central hole, and the hollow stud on the back surface of the bracket assembly (14) can be inserted into the central hole of the main body (7); The inner surface of one end of the exhaust column (6) facing the main body (7) is processed with a first internal thread, and the one end of the exhaust column (6) facing the main body (7) can be inserted into the central hole of the main body (7) and threadedly connected with the hollow stud on the back surface of the bracket assembly (14); The inner surface of the other end of the exhaust column (6) away from the main body (7) is provided with a stepped surface, and the valve (4) is prevented in the exhaust column (6) and the edge of the valve (4) is placed on the stepped surface; The inner surface of the other end of the exhaust column (6) away from the main body (7) is also provided with a second internal thread, the spring (5) is sleeved on the outer surface of the exhaust column (6), and the hollow screw (3) is screwed together with the second internal thread in the exhaust column (6) after pressing the spring (5), fixing the inner valve (4).

2. A new type of explosion-proof device for power battery according to claim 1, characterized in that: A protective sleeve (2) is also provided, which is sleeved on the outer side of the hollow screw (3), the spring (5) and the exhaust column (6), and is pressed into the clamping groove provided on the back surface of the main body (7) by interference fit.

3. A new type of explosion-proof device for power battery according to claim 1, characterized in that: It also comprises an outer sealing ring (1) and an inner sealing ring (8), which are respectively embedded in the front surface and the back surface of the main body (7).

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