Directional explosion venting and liquid leakage preventing soft package battery and battery pack

Abstract

The utility model provides a directional explosion venting and liquid leakage preventing soft package battery and a battery pack, and relates to the technical field of batteries, the soft package battery comprises a sealing shell, a sealing strip and a soft package battery cell, an upper shell and a lower shell are buckled and connected to form a closed cavity, and the soft package battery cell is placed in the cavity; the limiting parts of the sealing strips of the upper shell and the lower shell are used for placing the tab sealing strips and the side edge sealing strips, and the surfaces of the sealing strips are coated with a layer of adhesive to be bonded with the outer surface of an aluminum plastic film of the soft package battery cell, so that the aluminum plastic film of the soft package battery cell is extruded and sealed by the upper sealing strip and the lower sealing strip, and the effects of safe explosion venting and liquid leakage prevention are achieved. The directional explosion venting and liquid leakage preventing soft package battery pack comprises a sealing shell, a sealing strip and a soft package battery cell which are arranged side by side.

Description

Technical Field

[0001] The utility model relates to the field of soft-pack batteries, in particular to a directional explosion-relief and liquid-leakage-proof soft-pack battery and a battery pack. Background Art

[0002] Soft-pack lithium-ion batteries have many advantages, such as high energy density, long cycle life, and no memory effect. However, in terms of structure, the top seal position of soft-pack batteries mostly uses heat seals between the pole ear and the aluminum-plastic film. Due to the long-term circulation of the battery, the battery may bulge, and the heat seal position may bring the risk of leakage. On the other hand, the heat generation at the pole ear of the high-rate soft-pack battery is serious. After a certain period of circulation, the aging of the aluminum-plastic film sealant may cause the risk of leakage at the pole ear and side seal of the soft-pack battery. Patent CN208848984 U discloses a highly sealed and leak-proof lithium-ion battery pole ear. Although the pole ear is sealed and buffered, its manufacturing process is cumbersome, the welding cost is high, and the battery energy density is reduced. Therefore, it is necessary to design a structure that does not change the original packaging process but can seal the heat-sealed edge of the battery cell. Summary of the invention

[0003] In view of the packaging leakage problem of soft-pack batteries, the utility model provides a directional explosion-venting and leakage-proof soft-pack battery and battery pack, the main purpose of which is to solve the soft-pack battery leakage problem caused by loose packaging of soft-pack batteries or aging of sealants.

[0004] The utility model is realized through the following technical solutions:

[0005] A directional explosion-venting and leak-proof soft-pack battery, comprising: a sealing shell, a sealing strip and a soft-pack battery cell;

[0006] The sealed shell is composed of an upper shell and a lower shell, which are of the same shape. The upper and lower shells are buckled together to form a closed cavity. The soft-pack battery cell is placed in the cavity, and the size of the soft-pack battery cell is consistent with the size of the cavity.

[0007] The upper shell and the lower shell are respectively composed of a bottom plate and a support part. The support part is vertically arranged around the bottom plate plane. A limiting protrusion is arranged in the bottom plate plane. The limiting protrusion and the support part constitute a limiting part for placing the sealing strip.

[0008] The sealing strip includes a tab sealing strip and a side sealing strip, which are in the shape of a long strip. The tab sealing strip is concave, and the tab placement is designed as a recessed spring sheet. A pressure relief groove is left in the middle of the side sealing strip.

[0009] In a further preferred embodiment, through holes are respectively provided at the four top corners of the sealing shell, and the upper and lower shells are fixed together with buckles or bolts.

[0010] In a further preferred embodiment, the height of the support portion is 1 / 2 of the thickness of the soft-pack battery cell.

[0011] In a further preferred embodiment, the sealing strip is a rubber sealing strip with temperature resistance and elasticity, selected from one of a nitrile rubber sealing strip, a polyurethane rubber sealing strip, a polyolefin elastic sealing strip, a silicone rubber sealing strip or a vulcanized rubber sealing strip.

[0012] In a further preferred embodiment, the sealing strip has a width selected from 2-5 mm and a height which is 0.5-1 mm greater than the height of the supporting portion.

[0013] In a further preferred embodiment, the sealing strip is placed between the aluminum-plastic film of the soft-pack battery cell and the limiting portion of the sealing strip of the upper shell or the lower shell.

[0014] In a further preferred embodiment, a layer of sticky glue is coated on the surface of the sealing strip to bond with the outer surface of the aluminum-plastic film of the soft-pack battery cell, and the aluminum-plastic film of the soft-pack battery cell is squeezed and sealed by the upper and lower sealing strips.

[0015] In a further preferred embodiment, the shape of the tab sealing strip spring piece is selected from an arc shape or a wave shape.

[0016] In a further preferred embodiment, the sealing shell material can be selected from one of rigid polyvinyl chloride, polyetheretherketone, polyamide, polybutylene terephthalate or polycarbonate.

[0017] This utility model patent also introduces a directional explosion-proof and leak-proof soft-pack battery pack, including a sealing shell, a sealing strip and a soft-pack battery cell arranged side by side;

[0018] The sealing shell comprises an upper shell, a middle shell and a lower shell;

[0019] The upper shell and the lower shell have the same shape, and are respectively composed of a bottom plate and a support portion. The bottom plate plane is provided with a support portion vertically upward along the four sides, and a limiting protrusion is provided in the bottom plate plane. The limiting protrusion and the support portion constitute a limiting portion for placing the sealing strip;

[0020] The middle shell is composed of a bottom plate and a support part. The upper and lower planes of the bottom plate are provided with support parts vertically upward along the four sides. The upper and lower planes of the bottom plate are provided with limiting protrusions. The limiting protrusions and the support part constitute a limiting part for placing the sealing strip.

[0021] The upper shell, the middle shell and the lower shell are buckled and connected in sequence to form a plurality of closed cavities, and the soft-pack battery cells are respectively placed in the cavities formed by the sealed shells, and the size of the soft-pack battery cells is consistent with the size of the cavity.

[0022] In a further preferred embodiment, through holes are correspondingly provided at the four top corners of the upper shell, the middle shell and the lower shell, and the upper, middle and lower shells are connected by through-hole buckles or bolts;

[0023] In a further preferred embodiment, the number of the middle shells can be selected from 2 to 8, and the actual number can be configured according to the battery cell requirements.

[0024] In a further preferred embodiment, the sealing strip is a rubber sealing strip with temperature resistance and elasticity, selected from one of a nitrile rubber sealing strip, a polyurethane rubber sealing strip, a polyolefin elastic sealing strip, a silicone rubber sealing strip or a vulcanized rubber sealing strip.

[0025] In a further preferred embodiment, the sealing strip is placed between the aluminum-plastic film of the soft-pack battery cell and the limiting portion of the upper shell, the middle shell or the lower shell.

[0026] In a further preferred embodiment, a layer of adhesive is coated on the surface of the sealing strip to bond with the outer surface of the soft-pack aluminum-plastic film, and the soft-pack battery core aluminum-plastic film is squeezed and sealed by the upper and lower sealing strips.

[0027] In a further preferred embodiment, the shape of the tab sealing strip spring piece is selected from an arc shape or a wave shape.

[0028] In a further preferred embodiment, the sealing shell material can be selected from one of rigid polyvinyl chloride, polyetheretherketone, polyamide, polybutylene terephthalate or polycarbonate.

[0029] The utility model provides a directional explosion-proof and leak-proof soft-pack battery and battery pack, which has the following beneficial effects:

[0030] First, the setting of the sealing shell and the sealing strip can provide a certain extrusion pressure to the battery cell packaging position when the battery cell is not tightly packaged or the battery cell is bulging, thereby preventing the battery cell from leaking. At the same time, it can fix the battery cell, prevent the battery cells from moving relative to each other, and prevent pulling at the electrode ear welding point; second, the battery cell with unfolded edge of aluminum-plastic film can be used in the present application, and the edge of the battery cell can be directly cut after packaging. On the basis of controlling the size of the battery cell, one manufacturing process can be reduced; third, the interval between the battery cells in the battery pack of the present application can be freely controlled, which greatly improves the heat dissipation effect between the battery cells; finally, the material used is relatively light in weight, and while providing enhanced sealing for the battery pack, the energy density of the battery pack is lost very little. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 An exploded view of a single-side tab soft-pack battery provided in Example 1 of the utility model.

[0032] Figure 2 An exploded view of a double-sided tab soft-pack battery provided in Example 1 of the utility model.

[0033] Figure 3 A schematic diagram of an upper shell of a soft-pack battery provided in Example 1 of the utility model.

[0034] Figure 4 A schematic diagram of a tab sealing strip for a soft-pack battery provided in Example 1 of the utility model.

[0035] Figure 5 A schematic diagram of a soft-pack battery sealing strip provided in Example 1 of the utility model.

[0036] Figure 6 An exploded view of a single-side tab soft-pack battery pack provided in Example 2 of the utility model.

[0037] Figure 7 An exploded view of a double-sided tab soft-pack battery pack provided in Example 2 of the utility model.

[0038] Icons: 1. Sealing shell; 2. Sealing strip; 3. Soft-pack battery cell; 11. Upper shell; 12. Lower shell; 13. Middle shell; 21. Side sealing strip; 22. Tab sealing strip; 23. Side sealing strip pressure relief groove; 40. Bottom plate; 41. Support part; 42. Limiting protrusion; 43. Through hole; 44. Buckle. Implementation

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same figure marks in the figures represent the same or similar parts, and thus their repeated description will be omitted.

[0040] In the description of the present utility model application, it should be understood that the terms "vertical", "lateral", "length", "width", "thickness", "inside", "outside", 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 should not be understood as a limitation on the present application. Example 1

[0041] Figure 1 to Figure 5 This embodiment provides a directional explosion-proof and leak-proof soft-pack battery. The soft-pack battery cell 3 can be a single-side tab soft-pack battery cell such as Figure 1 As shown or double-sided tab soft pack battery Figure 2 As shown, the soft-pack battery cell 3 is placed in a sealed cavity formed by snapping and connecting the upper shell 11 and the lower shell 12 of the sealed shell 1, and the size of the soft-pack battery cell 3 is consistent with the size of the cavity.

[0042] The sealing shell 1 is made of hard polyvinyl chloride.

[0043] like Figure 3 The bottom plate 40 of the upper shell 11 and the lower shell 12 is provided with a support portion 41 vertically upward around the plane, and a limiting protrusion 42 is provided in the bottom plate plane. The limiting protrusion 42 and the support portion 41 constitute a limiting portion for placing the sealing strip;

[0044] The sealing strip 2 includes a tab sealing strip 22 and a side sealing strip 21 , and the tab sealing strip 22 and the side sealing strip 21 are respectively placed at corresponding positions in the limiting parts of the upper shell 11 and the lower shell 12 .

[0045] The soft-pack battery cell 3 is placed in the cavity of the sealing shell 1, and the surrounding heat-plastic sealing area contacts and squeezes the sealing strip 2. A layer of adhesive is applied where the surface of the sealing strip 2 contacts the surface of the aluminum-plastic film of the soft-pack battery to fix the position and improve the convenience of installation. The tab sealing strip 22 is designed with a concave spring piece corresponding to the tab placement, mainly to provide a certain extrusion force to the tab heat-sealed area, to play a role in sealing and preventing liquid leakage.

[0046] The height of the support portion 41 is 1 / 2 of the thickness of the soft-pack battery cell.

[0047] The sealing strip 2 is a polyurethane rubber sealing strip, the width of which is selected to be 4 mm, and the height of which is 1 mm greater than the height of the supporting portion.

[0048] Through holes 43 are provided at the four top corners of the sealing shell 1. Fastening devices of staples 44 are inserted into the through holes 43 to provide fastening pressure to overcome the problem of leakage in the heat-sealed area due to loose heat sealing or bulging.

[0049] In some embodiments of the present application, the shape of the tab sealing strip 22 is not limited to Figure 4 Medium style.

[0050] The side sealing strip 21 of the present application can also be adopted Figure 5 As shown, the design of setting a pressure relief groove in the middle position allows the pressure to be released in a directional manner in the pressure relief groove when the battery is bloated. Example 2

[0051] Figure 6-7 This embodiment provides a directional explosion-proof and leak-proof soft-pack battery pack, in which the soft-pack battery cell 3 can be a single-side tab soft-pack battery cell such as Figure 6 As shown or double-sided tab soft pack battery Figure 7 As shown, it includes a sealing shell 1, a sealing strip 2 and a plurality of soft-pack battery cells 3 arranged side by side. The sealing shell 1 is composed of an upper shell 11, a middle shell 13 and a lower shell 12. The upper shell 11 is located at the top of the soft-pack battery pack, the lower shell 12 is located at the bottom of the soft-pack battery pack, and the middle shell 13 is located between the soft-pack battery cells, and the number of the middle shell 13 matches the number of the soft-pack battery cells.

[0052] The upper shell 11, the middle shell 13 and the lower shell 12 are buckled and connected in sequence to form a plurality of sealed cavities, and a plurality of soft-packed battery cells 3 are respectively placed in the cavities formed by the sealed shell 1, and the size of the soft-packed battery cells 3 is consistent with the size of the cavity.

[0053] The sealing shell 1 is made of polyamide.

[0054] The support portion 13 of the sealing shell 1 and the limiting protrusions 14 arranged around the bottom plane constitute the limiting portion for placing the sealing strip 2, and the sealing strip 2 is placed in the limiting portions of the upper shell 11 and the lower shell 12. Support portions are arranged around the outer side of the bottom plane of the middle shell 13, and limiting protrusions are arranged on the upper and lower planes of the bottom plate. The limiting protrusions and the support portions constitute the limiting portion for placing the sealing strip, and the sealing strips 2 are placed in the limiting portions on both the upper and lower sides of the middle shell 13.

[0055] The sealing strip 2 includes a tab sealing strip 22 and a side sealing strip 21. After the soft-pack battery cell 3 is placed in the cavity of the sealing shell 1, the surrounding heat-sealed area contacts and squeezes the sealing strip 2 for sealing. A layer of adhesive is applied where the surface of the sealing strip 2 contacts the surface of the aluminum-plastic film of the soft-pack battery to fix the position and improve the convenience of installation. The tab sealing strip 22 is designed with a concave spring piece corresponding to the tab placement, mainly to provide a certain extrusion force to the tab heat-sealed area, to play a role in sealing and preventing liquid leakage.

[0056] The height of the support portion 41 is 1 / 2 of the thickness of the soft-pack battery cell.

[0057] The sealing strip 2 is a polyurethane rubber sealing strip, the width of which is selected to be 4 mm, and the height of which is greater than the height of the support portion by 0.8 mm.

[0058] Through holes 15 are provided at the four top corners of the sealing shell 1. The screws pass through the middle shell 13 from the upper shell 11 in sequence, and pass through the through holes of the lower shell 12 to be fixed with nuts, so as to tighten and pressurize the battery cell by locking the screws. This connection is not limited to the detachable connection of the screws, but mainly plays the role of confining the sealing shell and the soft-pack battery cell, so as to overcome the problem of leakage in the heat-sealed area due to poor heat sealing or bulging in the heat-sealed area.

Claims

1. A directional explosion-proof and leak-proof soft-pack battery, characterized in that: The soft-pack battery comprises: a sealing shell, a sealing strip and a soft-pack battery cell; The sealed shell is composed of an upper shell and a lower shell, which are of the same shape. The upper and lower shells are buckled and connected to form a closed cavity. The soft-packed battery cell is placed in the cavity, and the size of the soft-packed battery cell is consistent with the size of the cavity. The upper shell and the lower shell are respectively composed of a bottom plate and a support part. The support part is vertically arranged around the bottom plate plane. A limiting protrusion is arranged in the bottom plate plane. The limiting protrusion and the support part constitute a limiting part for placing the sealing strip. The sealing strip includes a tab sealing strip and a side sealing strip, and is in the shape of a long strip. The tab sealing strip is concave, and the tab placement position is designed as a recessed spring sheet. The side sealing strip is provided with a pressure relief groove.

2. A directional explosion-proof and leak-proof soft-pack battery according to claim 1, characterized in that: The four top corners of the sealing shell are respectively provided with through holes, which are used in conjunction with buckles or bolts to fix the upper shell and the lower shell.

3. A directional explosion-proof and leak-proof soft-pack battery according to claim 1, characterized in that: The height of the support portion is 1 / 2 of the thickness of the soft-pack battery cell.

4. A directional explosion-proof and leak-proof soft-pack battery according to claim 1, characterized in that: The sealing strip is a rubber sealing strip with temperature resistance and elasticity, selected from one of nitrile rubber sealing strip, polyurethane rubber sealing strip, polyolefin elastic sealing strip, silicone rubber sealing strip or vulcanized rubber sealing strip.

5. The directional explosion-proof and leak-proof soft-pack battery according to claim 1, characterized in that: The sealing strip has a width of 2-5 mm and a height which is 0.5-1 mm greater than the height of the supporting portion.

6. A directional explosion-proof and leak-proof soft-pack battery according to claim 1, characterized in that: The sealing strip is located between the aluminum-plastic film of the soft-pack battery core and the sealing strip limiting portion of the upper shell or the lower shell.

7. A directional explosion-proof and leak-proof soft-pack battery according to claim 1, characterized in that: A layer of sticky glue is coated on the surface of the sealing strip to bond with the outer surface of the soft-pack aluminum-plastic film, and the soft-pack battery core aluminum-plastic film is squeezed and sealed by the upper and lower sealing strips.

8. The directional explosion-proof and leak-proof soft-pack battery according to claim 1, characterized in that: The shape of the tab sealing strip spring piece is selected from arc shape or wave shape.

9. The directional explosion-proof and leak-proof soft-pack battery according to claim 1, characterized in that: The sealing shell material can be selected from one of rigid polyvinyl chloride, polyetheretherketone, polyamide, polybutylene terephthalate or polycarbonate.

10. A directional explosion-proof and leak-proof soft-pack battery pack, characterized in that: The battery pack comprises a sealing shell, a sealing strip and a soft-pack battery cell arranged side by side; The sealing shell comprises an upper shell, a middle shell and a lower shell; The upper shell and the lower shell are selected from the upper shell and the lower shell of a directional explosion-proof and leak-proof soft-pack battery as described in any one of claims 1 to 9; The middle shell is composed of a bottom plate and a support part. The upper and lower planes of the bottom plate are provided with support parts vertically upward along the four sides. The upper and lower planes of the bottom plate are provided with limiting protrusions. The limiting protrusions and the support part constitute a limiting part for placing the sealing strip. The upper shell, the middle shell and the lower shell are buckled and connected in sequence to form a plurality of closed cavities, and the soft-packed battery cells are respectively placed in the cavities, and the size of the soft-packed battery cells is consistent with the size of the cavity; The sealing strip is selected from the sealing strip of a directional explosion-proof and leak-proof soft-pack battery as described in any one of claims 1 to 9.

11. A directional explosion-proof and leak-proof soft-pack battery pack according to claim 10, characterized in that: Through holes are correspondingly provided at four top corners of the upper shell, the middle shell and the lower shell, and the upper, middle and lower shells are connected by through-hole buckles or bolts.

12. A directional explosion-proof and leak-proof soft-pack battery pack according to claim 10, characterized in that: There can be one upper shell and one lower shell, and the number of the middle shells can be selected from 2 to 8.

13. A directional explosion-proof and liquid-leakage-proof soft-pack battery pack according to claim 10, characterized in that: The sealing strip is located between the aluminum-plastic film of the soft-pack battery core and the limiting part of the upper shell, the middle shell or the lower shell. A layer of adhesive is coated on the surface of the sealing strip to bond with the outer surface of the aluminum-plastic film of the soft-pack battery core. The aluminum-plastic film of the soft-pack battery core is squeezed and sealed by the sealing strip.

14. A directional explosion-proof and leak-proof soft-pack battery pack according to claim 10, characterized in that: The sealing shell material can be selected from one of rigid polyvinyl chloride, polyetheretherketone, polyamide, polybutylene terephthalate or polycarbonate.

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