Soft package battery structure

Abstract

The utility model relates to a soft package battery structure, which comprises a battery body, and the battery body comprises a battery cell and a soft package shell covering the periphery of the battery cell; the exhaust and liquid supplement pipe is connected with the battery body, a liquid injection and exhaust hole is formed in the exhaust and liquid supplement pipe, and an exhaust buffer port is formed in the liquid injection and exhaust hole; and the exhausting and liquid supplementing cover is detachably connected with the exhausting and liquid supplementing pipe, and the exhausting and liquid supplementing cover and the exhausting and liquid supplementing pipe are connected in a sealed mode to block the liquid injection and exhausting hole. According to the soft package battery structure disclosed by the invention, the battery body is additionally provided with the exhausting and liquid supplementing pipe, and the exhausting and liquid supplementing pipe can be used for exhausting gas in time according to the appearance of the soft package battery, so that the safety problems of liquid leakage and even thermal runaway caused by gas expansion of the soft package battery are avoided; and secondly, the gas in the soft package battery is discharged, so that good interface contact of the battery cell is favorably kept, and the stable operation of the battery is ensured. And the additionally arranged exhaust liquid replenishing pipe can be used for carrying out lossless liquid replenishing on the battery, so that the cycle performance of the battery can be maintained.

Description

Technical Field

[0001] The present application relates to the technical field of soft-pack secondary batteries, and in particular to a soft-pack battery structure. Background Art

[0002] Soft-pack lithium-ion batteries use lightweight aluminum-plastic film as the battery shell material. Therefore, soft-pack lithium-ion batteries have the advantage of energy density and have been widely used in smart wearables, mobile phones, laptops and other fields in recent years. In the context of global carbon emission reduction, passenger cars are gradually electrified, and the promotion and use of power soft-pack lithium-ion batteries in the passenger car field are gradually increasing. Power soft-pack lithium-ion batteries have the characteristics of high single-cell capacity, long life and high number of cycles.

[0003] In the prior art, in the process of producing soft-pack lithium-ion batteries, an air bag method is generally used to store the gas generated by the initial activation of the battery. As the capacity of the battery cell increases, the attached air bag becomes larger and larger, and the air needs to be exhausted and removed after the activation is completed. The process is cumbersome and adds additional costs. In addition, the existing power soft-pack lithium-ion batteries use a heat-sealed aluminum-plastic film on all sides, which cannot achieve secondary fluid replenishment and cannot efficiently utilize the residual value of the battery, resulting in a short battery life and difficulty in achieving multiple recycling. Summary of the invention

[0004] The embodiment of the present application provides a soft-pack battery structure to solve the problem that the aluminum-plastic film of the soft-pack battery in the related art is easily damaged due to battery gas production, thereby causing electrolyte leakage.

[0005] The present application provides a soft pack battery structure, including:

[0006] A battery body, the battery body comprising a battery cell and a soft package casing covering the outer periphery of the battery cell;

[0007] an exhaust and liquid-replenishing tube connected to the battery body, with one end of the exhaust and liquid-replenishing tube extending into the soft-pack shell and the other end extending out of the soft-pack shell, the exhaust and liquid-replenishing tube comprising an injection exhaust hole, and an exhaust buffer port being arranged in the injection exhaust hole;

[0008] The exhaust and liquid replenishing cover is arranged at one end of the exhaust and liquid replenishing tube extending outside the soft package shell, and the exhaust and liquid replenishing cover is detachably connected to the exhaust and liquid replenishing tube, and the exhaust and liquid replenishing cover and the exhaust and liquid replenishing tube are sealed and connected to each other to block the liquid injection exhaust hole.

[0009] In some embodiments: a through hole is provided on the soft package shell to allow one end of the exhaust and liquid-replenishing tube to extend into the interior of the battery body, and the soft package shell and the outer wall of the exhaust and liquid-replenishing tube are connected to each other via a bonding member.

[0010] In some embodiments: the exhaust buffer port is a trumpet-shaped structure, the exhaust buffer port is arranged at one end of the exhaust and rehydration tube close to the battery body, and the large-diameter end of the exhaust buffer port is connected to the inner wall of the exhaust and rehydration tube, and the small-diameter end of the exhaust buffer port is suspended in the exhaust and rehydration tube and faces the battery body.

[0011] In some embodiments: the diameter of the small-diameter end of the exhaust buffer port is between 1 / 4 and 1 / 2 of the inner diameter of the exhaust and liquid replenishing tube.

[0012] In some embodiments, the distance between the small-diameter end of the exhaust buffer port and the end of the exhaust and liquid replenishing tube close to the battery body is 0-3 mm.

[0013] In some embodiments: the end of the exhaust and liquid replenishing tube extending into the interior of the battery body is 2 mm-5 mm away from the battery cell.

[0014] In some embodiments: the exhaust and fluid replenishment cover includes an inner section and an exposed section that are interconnected, the inner section extends into the exhaust and fluid replenishment tube and is sealed and connected to the exhaust and fluid replenishment tube, and the exposed section is located outside the exhaust and fluid replenishment tube to extend into or pull out the inner section.

[0015] In some embodiments: the inner connecting section is provided with an external thread connected to the exhaust and liquid replenishing tube, the exhaust and liquid replenishing tube is provided with an internal thread connected to the inner connecting section, and the exposed section is provided with anti-slip grooves.

[0016] In some embodiments: a sealing ring for sealingly connecting the exhaust and liquid-infusion tube is provided on the inner connecting section, anti-slip grooves are provided on the exposed section, and an undercut for bucklingly connecting with the exhaust and liquid-infusion tube is provided on the inner connecting section.

[0017] In some embodiments: a filter is provided in the exhaust buffer port.

[0018] The beneficial effects of the technical solution provided by this application include:

[0019] An embodiment of the present application provides a soft-pack battery structure. Since the soft-pack battery structure of the present application is provided with a battery body, the battery body includes a battery cell and a soft-pack shell covering the periphery of the battery cell; an exhaust and rehydration tube, which is connected to the battery body, and a liquid injection exhaust hole is provided on the exhaust and rehydration tube, and an exhaust buffer port is provided in the liquid injection exhaust hole; an exhaust and rehydration cover, which is detachably connected to the exhaust and rehydration tube, and the exhaust and rehydration cover and the exhaust and rehydration tube are sealed and connected to each other to block the liquid injection exhaust hole.

[0020] Therefore, the battery body of the soft-pack battery structure of the present application is additionally provided with an exhaust and refilling tube, which can discharge gas in time according to the appearance of the soft-pack battery, avoiding leakage of the soft-pack battery due to bloating, and even safety issues such as thermal runaway; secondly, the removal of gas in the soft-pack battery helps the battery cells maintain good interface contact and ensure the smooth operation of the battery. With the increase in the number of soft-pack battery cycles, the electrolyte is constantly consumed, and the lack of electrolyte will cause the battery capacity to decay rapidly, and in severe cases, the battery will dive. The additional exhaust and refilling tube can refill the battery without loss, which is beneficial to maintaining the battery cycle performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 This is a structural front view of the soft-pack battery structure of the embodiment of the present application;

[0023] Figure 2 This is a schematic diagram of the assembly of the exhaust and liquid replenishing tube and the exhaust and liquid replenishing cover of the embodiment of the present application;

[0024] Figure 3 This is a structural explosion diagram of the exhaust and liquid replenishment pipe and the exhaust and liquid replenishment cover of the embodiment of the present application.

[0025] Reference numerals:

[0026] 10. Battery body; 11. Battery cell; 12. Soft-pack shell; 20. Exhaust and liquid-replenishing tube; 21. Liquid-injection exhaust hole; 22. Exhaust buffer port; 30. Exhaust and liquid-replenishing cap; 31. Internal section; 32. Exposed section. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0028] The embodiment of the present application provides a soft-pack battery structure, which can solve the problem in the related art that the aluminum-plastic film of the soft-pack battery is easily damaged due to battery gas production, thereby causing electrolyte leakage.

[0029] See also Figures 1 to 3 As shown, the embodiment of the present application provides a soft pack battery structure, including:

[0030] The battery body 10 includes a battery cell 11 and a soft-package shell 12 wrapped around the outer periphery of the battery cell 11. The battery cell 11 includes a battery cell body and a tab unit, and the battery cell body includes a plurality of positive electrode sheets, a negative electrode sheet and a separator, and the plurality of positive electrode sheets and the plurality of negative electrode sheets are stacked. The battery cell 11 can be a wound battery cell or a laminated battery cell.

[0031] A diaphragm is provided between the adjacent positive and negative pole sheets, and the tab unit is connected to the battery body, and the tab unit includes a positive tab and a negative tab. The positive tab and the negative tab extend out of the soft-package shell 12, and the soft-package shell 12 is an aluminum-plastic film to protect the battery cell 11 and the electrolyte.

[0032] The exhaust and liquid-replenishing tube 20 is connected to the battery body 10, and one end of the exhaust and liquid-replenishing tube 20 extends into the soft-pack shell 12, and the other end extends out of the soft-pack shell 12. The exhaust and liquid-replenishing tube 20 includes a liquid injection vent 21. The exhaust and liquid-replenishing tube 20 is used to discharge the gas in the battery body 10, and can also achieve multiple liquid replenishment through the liquid injection vent 21, effectively improving the cascade utilization value of the battery, realizing the cascade utilization of old battery cells, and thus reducing the manufacturing cost of the battery.

[0033] An exhaust buffer port 22 is provided in the liquid injection exhaust hole 21, and the exhaust buffer port 22 can prevent a small amount of electrolyte from directly splashing out of the liquid injection exhaust hole 21 when exhausting. The exhaust buffer port 22 has the function of exhausting liquid and preventing the gas with high pressure from carrying part of the electrolyte and spraying out together when exhausting, thereby preventing safety hazards.

[0034] The exhaust and liquid replenishment cap 30 is arranged at one end of the exhaust and liquid replenishment tube 20 extending outside the soft pack shell 12, and the exhaust and liquid replenishment cap 30 is detachably connected to the exhaust and liquid replenishment tube 20, and the exhaust and liquid replenishment cap 30 and the exhaust and liquid replenishment tube 20 are sealed and connected to each other to block the liquid injection vent 21. When the liquid injection vent 21 does not need to be vented or replenished, the exhaust and liquid replenishment cap 30 is used to block the liquid injection vent 21 to prevent the electrolyte in the battery from leaking or evaporating.

[0035] The battery body 10 of the soft-pack battery structure of the embodiment of the present application is additionally provided with an exhaust and refilling tube 20, which can discharge gas in a timely manner according to the appearance of the soft-pack battery, thereby avoiding leakage of the soft-pack battery due to bloating, or even safety issues such as thermal runaway; secondly, the removal of gas from the soft-pack battery helps the battery cell 11 maintain good interface contact, thereby ensuring the smooth operation of the battery.

[0036] As the number of cycles of the soft-pack battery increases, the electrolyte is continuously consumed. The lack of electrolyte will lead to a rapid decay of the battery capacity. In severe cases, the battery may even dive. The exhaust and rehydration pipe 20 added in the embodiment of the present application can also perform non-destructive rehydration of the battery, which is beneficial to maintaining the battery cycle performance.

[0037] In some alternative embodiments: See Figure 1 As shown, an embodiment of the present application provides a soft-pack battery structure, in which a through hole is provided on the soft-pack shell 12 for allowing one end of the exhaust and liquid replenishment tube 230 to extend into the interior of the battery body 10, and the soft-pack shell 12 and the outer wall of the exhaust and liquid replenishment tube 20 are connected to each other by an adhesive.

[0038] In some optional embodiments, the adhesive member may be adhesive tape or glue.

[0039] In some optional embodiments, the adhesive member may be a sealant, so as to achieve a sealed connection between the soft package shell 12 and the outer wall of the exhaust and liquid replenishing tube 20 .

[0040] In some alternative embodiments: See Figure 1 As shown, an embodiment of the present application provides a soft-pack battery structure, in which the exhaust buffer port 22 is a trumpet-shaped structure, and the exhaust buffer port 22 is arranged at one end of the exhaust and rehydration tube 20 close to the battery body 10, and the large-diameter end of the exhaust buffer port 22 is connected to the inner wall of the exhaust and rehydration tube 20, and the small-diameter end of the exhaust buffer port 22 is suspended in the exhaust and rehydration tube 20 and faces the battery body 10.

[0041] The diameter of the small-diameter end of the exhaust buffer port 22 is between 1 / 4 and 1 / 2 of the inner diameter of the exhaust and refilling tube 20. The distance between the small-diameter end of the exhaust buffer port 22 and the end of the exhaust and refilling tube 20 close to the battery cell 11 is 0-3 mm. The exhaust buffer port 22 forms an inverted cone structure in the exhaust and refilling tube 20. The exhaust buffer port 22 of the inverted cone structure has the function of forward connection and reverse cutoff, and when normal exhaust and refilling are met, a large amount of electrolyte is prevented from being ejected during exhaust.

[0042] In some alternative embodiments: See Figure 1 As shown, an embodiment of the present application provides a soft-pack battery structure, in which the exhaust and rehydration tube 20 of the soft-pack battery structure extends into the battery body 10 and the distance between one end and the battery cell 11 is 2mm-5mm, so as to prevent the exhaust and rehydration tube 20 from being too close to the battery cell 11 and affecting the normal charging and discharging of the battery cell 11.

[0043] In some alternative embodiments: See Figures 1 to 3As shown, an embodiment of the present application provides a soft-pack battery structure, and the exhaust and liquid replenishment cover 30 of the soft-pack battery structure includes an inner section 31 and an exposed section 32 that are connected to each other. The inner section 31 extends into the exhaust and liquid replenishment tube 20 and is sealed and connected to the exhaust and liquid replenishment tube 20, and the exposed section 32 is located outside the exhaust and liquid replenishment tube 20 to extend into or pull out the inner section 31.

[0044] Specifically, the inner connecting section 31 is provided with an external thread connected to the exhaust and liquid replenishing tube 20, and the exhaust and liquid replenishing tube 20 is provided with an internal thread connected to the inner connecting section 31, and the inner connecting section 31 and the exhaust and liquid replenishing tube 20 are connected to each other through threads. The inner connecting section 31 and the exhaust and liquid replenishing tube 20 connected to each other by threads have good connection strength and mutual sealing performance. The exposed section 32 is provided with anti-slip grooves, and the exposed section 32 is used to tighten or loosen the inner connecting section 31, so as to facilitate the disassembly and assembly of the inner connecting section 31.

[0045] Alternatively, a sealing ring (not shown) for sealingly connecting the exhaust and liquid-infusion tube 20 is provided on the inner connecting section 31, and the inner connecting section 31 is directly inserted into the exhaust and liquid-infusion tube 20 and radially sealed with each other by the sealing ring. Anti-slip grooves are provided on the exposed section 32, and an undercut (not shown) for snap-connecting with the exhaust and liquid-infusion tube 20 is provided on the inner connecting section 31, and the undercut is used to prevent the inner connecting section 31 from falling out of the exhaust and liquid-infusion tube 20.

[0046] A filter (not shown) is provided in the exhaust buffer port 22 to prevent foreign matter from falling into the battery cell 11 when the battery body 10 is replenished with liquid.

[0047] How it works

[0048] An embodiment of the present application provides a soft-pack battery structure. The soft-pack battery structure of the present application is provided with a battery body 10, which includes a battery cell 11 and a soft-pack shell 12 covering the outer periphery of the battery cell 11; an exhaust and liquid replenishing tube 20, which is connected to the battery body 10, and a liquid injection exhaust hole 21 is provided on the exhaust and liquid replenishing tube 20, and an exhaust buffer port 22 is provided in the liquid injection exhaust hole 21; an exhaust and liquid replenishing cover 30, which is detachably connected to the exhaust and liquid replenishing tube 20, and the exhaust and liquid replenishing cover 30 and the exhaust and liquid replenishing tube 20 are sealed and connected to each other to block the liquid injection exhaust hole 21.

[0049] Therefore, the battery body 10 of the soft-pack battery structure of the present application is additionally provided with an exhaust and refilling tube 20, which can discharge gas in time according to the appearance of the soft-pack battery, avoiding leakage of the soft-pack battery due to bloating, and even safety issues such as thermal runaway; secondly, the removal of gas in the soft-pack battery helps the battery cells maintain good interface contact and ensure the smooth operation of the battery. With the increase in the number of soft-pack battery cycles, the electrolyte is constantly consumed, and the lack of electrolyte will cause the battery capacity to decay rapidly, and in severe cases, the battery will dive. The additional exhaust and refilling tube 20 can refill the battery without loss, which is beneficial to maintaining the battery cycle performance.

[0050] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0051] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0052] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A soft pack battery structure, characterized in that: include: A battery body (10), the battery body (10) comprising a battery cell (11) and a soft-package casing (12) covering the outer periphery of the battery cell (11); an exhaust and liquid-replenishing tube (20), which is connected to the battery body (10), and one end of the exhaust and liquid-replenishing tube (20) extends into the soft-package shell (12), and the other end extends out of the soft-package shell (12), the exhaust and liquid-replenishing tube (20) comprises a liquid injection exhaust hole (21), and an exhaust buffer port (22) is provided in the liquid injection exhaust hole (21); The exhaust and liquid replenishing cover (30) is arranged at one end of the exhaust and liquid replenishing tube (20) extending outside the soft package shell (12), and the exhaust and liquid replenishing cover (30) is detachably connected to the exhaust and liquid replenishing tube (20), and the exhaust and liquid replenishing cover (30) and the exhaust and liquid replenishing tube (20) are sealed to each other to block the liquid injection exhaust hole (21).

2. A soft pack battery structure as claimed in claim 1, characterized in that: The soft-package shell (12) is provided with a through hole for allowing one end of the exhaust and liquid-replenishing tube (20) to extend into the interior of the battery body (10); the soft-package shell (12) and the outer wall of the exhaust and liquid-replenishing tube (20) are connected to each other via an adhesive.

3. A soft pack battery structure as claimed in claim 1, characterized in that: The exhaust buffer port (22) is a trumpet-shaped structure, and is arranged at one end of the exhaust and liquid replenishing pipe (20) close to the battery body (10), and the end with a large diameter of the exhaust buffer port (22) is connected to the inner wall of the exhaust and liquid replenishing pipe (20), and the end with a small diameter of the exhaust buffer port (22) is suspended in the exhaust and liquid replenishing pipe (20) and faces the battery body (10).

4. A soft pack battery structure as claimed in claim 3, characterized in that: The diameter of the small-diameter end of the exhaust buffer port (22) is between 1 / 4 and 1 / 2 of the inner diameter of the exhaust and liquid replenishing pipe (20).

5. A soft pack battery structure as claimed in claim 3, characterized in that: The distance between the small-diameter end of the exhaust buffer port (22) and the end of the exhaust and liquid replenishing tube (20) close to the battery body (10) is 0-3 mm.

6. A soft pack battery structure as claimed in claim 1, characterized in that: One end of the exhaust and liquid replenishing pipe (20) extending into the interior of the battery body (10) is 2 mm to 5 mm away from the battery cell (11).

7. A soft pack battery structure according to claim 1, characterized in that: The exhaust and liquid-replenishing cover (30) comprises an inner connecting section (31) and an outer exposed section (32) which are connected to each other, wherein the inner connecting section (31) extends into the exhaust and liquid-replenishing tube (20) and is sealedly connected to the exhaust and liquid-replenishing tube (20), and the outer exposed section (32) is located outside the exhaust and liquid-replenishing tube (20) so as to extend into or remove the inner connecting section (31).

8. A soft pack battery structure as claimed in claim 7, characterized in that: The inner connecting section (31) is provided with an external thread connected to the exhaust and liquid replenishing tube (20), the exhaust and liquid replenishing tube (20) is provided with an internal thread connected to the inner connecting section (31), and the exposed section (32) is provided with an anti-slip pattern.

9. A soft pack battery structure as claimed in claim 7, characterized in that: The inner connecting section (31) is provided with a sealing ring for sealingly connecting the exhaust and liquid replenishing tube (20), the exposed section (32) is provided with anti-slip grooves, and the inner connecting section (31) is provided with an undercut for snap-fit ​​connection with the exhaust and liquid replenishing tube (20).

10. The soft pack battery structure according to claim 1, characterized in that: A filter screen is provided in the exhaust buffer port (22).

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