Soft package battery

Abstract

The utility model provides a soft package battery, which belongs to the field of soft package batteries and comprises at least one exhaust passage arranged on a battery main body. The gas storage bag is arranged outside the battery main body and is provided with a gas inlet; two ends of the air duct are respectively communicated with the exhaust passage and the air inlet; the one-way circulation piece is arranged in the air guide pipe; the exhaust passage abuts against the top of the battery main body; and the one-way circulating piece enables gas in the battery main body to flow into the gas storage bag from the exhaust passage to the gas inlet in a one-way manner. According to the utility model, the exhaust passage is arranged at the top of the soft package bag of the battery main body, and the exhaust passage is communicated with the external gas storage bag through the gas guide pipe with the guide circulation piece, so that gas generated in the aging process can be guided to be exhausted, and the gas is effectively prevented from reversely permeating into the soft package bag of the battery from the gas storage bag; meanwhile, the exhaust passage is positioned at the top of the battery main body and is communicated with the gas guide pipe, so that the problem of insufficient electrolyte retention capacity caused by the fact that the electrolyte is discharged along with gas produced by the battery cell can be effectively relieved.

Description

Technical Field

[0001] This utility model relates to the field of soft-pack battery technology, and in particular to a soft-pack battery. Background Technology

[0002] Pouch batteries are widely used in mobile devices, electric vehicles, and energy storage systems due to their high energy density, good safety performance, and light weight. Current pouch battery production typically uses an aluminum-plastic film casing, stacking electrode sheets and placing them inside the casing, then injecting a certain amount of electrolyte and "activating" them through a formation process. With the widespread use of positive electrode lithium replenishment technology, most lithium replenishment agents decompose and produce gas. If the electrode sheets or electrolyte absorb water during manufacturing, or if lithium replenishment agents are added to the battery to increase capacity, the battery is prone to generating excessive gas during formation, causing the battery to swell or even crack, and electrolyte leakage, thus affecting battery performance.

[0003] Chinese patent CN208284505U discloses a battery pouch and a pouch battery including the same. The pouch features a one-way valve that opens when the gas pressure within the containment space reaches a set value, allowing gas to escape from the containment space and preventing gas from the outside of the pouch from entering the containment space. However, this method of venting gas generated during pouch battery formation into the gas bag can easily carry away the electrolyte. During vacuuming, secondary sealing, and cutting processes, electrolyte can be removed from the gas bag, resulting in insufficient electrolyte retention in the pouch battery. Utility Model Content

[0004] In view of this, the present invention proposes a soft-pack battery to solve the problem that the current method of venting the gas generated during the formation of soft-pack batteries to the gas bag through a one-way valve easily carries away the electrolyte, resulting in insufficient electrolyte retention in the soft-pack battery.

[0005] The technical solution of this utility model is implemented as follows: This utility model provides a soft-pack battery, including a battery body with at least one exhaust duct on it; a gas storage bag externally placed outside the battery body and having an air inlet on it; a gas guide pipe with its two ends connected to the exhaust duct and the air inlet respectively; and a one-way flow member disposed inside the gas guide pipe; wherein, the one-way flow member allows the gas inside the battery body to flow unidirectionally from the exhaust duct to the air inlet into the gas storage bag.

[0006] Based on the above technical solutions, preferably, the battery body includes a first heat-sealing area that surrounds the outer shell of the battery body; a cell placement area that is disposed within the first heat-sealing area and forms the internal space of the battery body; and stacked cells that are disposed within the cell placement area; wherein, the side of the battery body with tabs is the top of the battery body, and the side opposite to the top of the battery body is the bottom of the battery body, and the exhaust channel is close to the top of the battery body; an exhaust channel is opened in the first heat-sealing area, and the exhaust channel connects the cell placement area and the vent pipe.

[0007] More preferably, it also includes a gas collecting pipe, with several exhaust channels spaced apart and parallel to each other in the first heat-sealed zone; the gas collecting pipe is located outside the battery body, with both ends of the gas collecting pipe extending toward the top and bottom of the battery body respectively and simultaneously connected to the outer ends of the several exhaust channels, and the end of the gas collecting pipe facing the top of the battery body is connected to the gas guide pipe.

[0008] More preferably, the side of the first heat-sealed area facing the tabs of the stacked cells is the top of the pouch battery, and the side of the first heat-sealed area opposite to the top of the pouch battery is the bottom of the pouch battery, with the inner end of the exhaust channel inclined outward along the bottom to the top of the pouch battery.

[0009] More preferably, the inclination angle of the exhaust duct is 45° relative to the horizontal direction.

[0010] Based on the above technical solutions, preferably, the one-way flow component includes a sealing sheet and an elastic element. A movable cavity is provided in the middle of the air guide tube, and the one-way flow component is provided in the movable cavity. The sealing sheet is provided at one end of the movable cavity near the exhaust port. The sealing sheet moves along the axial direction of the air guide tube in the movable cavity and closes or opens the air guide tube. The elastic element is provided between the sealing sheet and the end of the movable cavity near the air inlet. The two ends of the elastic element are respectively connected to the sealing sheet and the inner wall of the movable cavity. The elastic element compresses and holds the sealing sheet against the inner wall of the movable cavity.

[0011] Even more preferably, the sealing sheet is made of rubber material and the elastic element is a spring.

[0012] More preferably, the inner diameter of the movable cavity is larger than the outer diameter of the sealing sheet, and the outer diameter of the sealing sheet is larger than the inner diameter of the air guide tube.

[0013] Based on the above technical solutions, preferably, the first heat-sealing zone, the gas storage bag, and the gas guide pipe are made of the same material.

[0014] The soft-pack battery of this invention has the following advantages over the prior art:

[0015] (1) This utility model provides an exhaust channel at the top of the soft pack of the battery body and connects the exhaust channel to an external gas storage bag through a gas guide pipe with a guiding flow component. This can guide the gas generated during the aging process to be discharged and effectively prevent the gas from seeping back into the battery soft pack from the gas storage bag, thereby reducing the contact time between the gas and the electrode and effectively improving the interface of the soft pack battery electrode. At the same time, since the exhaust channel is located at the top of the battery body and is connected to the gas guide pipe, it can effectively alleviate the problem of insufficient electrolyte retention caused by the discharge of electrolyte with the gas generated by the cell.

[0016] (2) The exhaust duct of this utility model is inclined towards the top of the soft pack battery, which helps to alleviate the problem of electrolyte being discharged with the gas generated by the battery cell. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a side sectional view of the soft-pack battery of this utility model;

[0019] Figure 2 This is a side sectional view of the unidirectional flow component of this utility model.

[0020] In the diagram: 1. Battery body; 11. First heat-sealing area; 12. Cell placement area; 13. Stacked cells; 101. Exhaust duct; 2. Gas storage bag; 201. Air inlet; 3. Gas guide pipe; 31. Movable cavity; 4. One-way flow component; 41. Sealing sheet; 42. Elastic component; 5. Gas collection pipe. Detailed Implementation

[0021] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments of this utility model. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model.

[0022] like Figure 1 As shown, a soft-pack battery of this utility model includes a battery body 1, an air storage bag 2, an air duct 3, and a one-way flow component 4.

[0023] The battery body 1 is provided with at least one exhaust duct 101. The side of the battery body 1 with the tab is the top of the battery body 1, and the side opposite to the top of the battery body 1 is the bottom of the battery body 1. The exhaust duct 101 is close to the top of the battery body 1.

[0024] The air storage bag 2 is externally located outside the battery body 1 and has an air inlet 201 on it.

[0025] The two ends of the air duct 3 are connected to the exhaust duct 101 and the air inlet 201, respectively.

[0026] The one-way flow element 4 is installed inside the vent pipe 3, and its principle is similar to that of a one-way valve. The one-way flow element 4 allows the gas inside the battery body 1 to flow unidirectionally from the exhaust channel 101 to the inlet 201 into the gas storage bag 2.

[0027] Using the above technical solution, during the pressurized formation of the battery, the gas generated inside the battery body 1 will be discharged in time through the exhaust channel 101 under the action of external pressure, and enter the gas storage bag 2 through the gas guide pipe 3. The one-way flow member 4 restricts the gas from back seeping back into the battery body 1. At the same time, since the exhaust channel 101 is located near the top of the battery body 1, and the gas mainly accumulates in the upper part of the battery body 1, the problem of electrolyte being discharged with the gas generated by the cell can be alleviated.

[0028] exist Figure 1 In a preferred embodiment shown, the battery body 1 includes a first heat-sealing area 11, a cell placement area 12, and stacked cells 13.

[0029] The first heat-sealed area 11 forms the outer shell of the battery body 1, i.e., the first heat-sealed area 11 is the soft bag of the pouch battery, which is formed by two soft sheets aligned left and right and joined together at the outline edge. An exhaust channel 101 is formed within the first heat-sealed area 11, connecting the cell placement area 12 and the vent pipe 3. Since the soft bag of the battery body 1 is essentially formed by two soft sheets joined together, it wraps around the stacked cell 13 to form the battery body 1, and the edges of the two soft sheets are sealed together to form the soft bag.

[0030] The cell placement area 12 is located within the first heat-sealing area 11 and forms the internal space of the battery body 1.

[0031] The stacked cell 13 is disposed within the cell placement area 12. The stacked cell 13 generally consists of a positive electrode sheet, a negative electrode sheet, and a separator sandwiched between the positive and negative electrode sheets. The positive electrode sheet is connected to the positive electrode tab, and the negative electrode sheet is connected to the negative electrode tab. Both the positive and negative electrode tabs penetrate the first heat-sealing area 11 and extend out of the battery body 1.

[0032] Therefore, by adopting the above technical solution, during the pressurized formation, the gas generated by the stacked cells 13 is discharged in time through the exhaust channel 101 under external pressure; after the formation and overcharge process of the battery is completed, the cell setting area 12 is evacuated, and then heat-sealed along the edge of the first heat-sealing area 11. Finally, the gas guide tube 3 and the external gas storage bag 2 are cut off to obtain the finished soft-pack battery.

[0033] exist Figure 1 In a preferred embodiment shown, a gas collecting pipe 5 is also included.

[0034] In the first heat-sealing zone 11, several exhaust channels 101 are opened in parallel at intervals. The multiple exhaust channels 101 are arranged in parallel from top to bottom, which can make the gas generated in the battery body 1 more fully discharged.

[0035] The gas collecting pipe 5 is located outside the battery body 1. Both ends of the gas collecting pipe 5 extend toward the top and bottom of the battery body 1 respectively and are connected to the outer ends of several exhaust channels 101. The gas collecting pipe 5 collects the gas discharged from each exhaust channel 101. The end of the gas collecting pipe 5 facing the top of the battery body 1 is connected to the gas guide pipe 3 to alleviate the discharge of electrolyte along with the gas generated by the battery cell.

[0036] exist Figure 1 In a preferred embodiment shown, the inner end of the exhaust duct 101 is inclined from the bottom to the top of the soft-pack battery, so that a small amount of electrolyte ejected with the exhaust can flow back into the battery body 1 along the upwardly inclined exhaust duct, thereby alleviating the discharge of electrolyte with the gas generated by the battery cell.

[0037] exist Figure 1 In a preferred embodiment shown, the exhaust duct 101 is tilted at an angle of 45° relative to the horizontal direction, giving the exhaust duct 101 a longer length, which is beneficial for electrolyte reflux, and the angle also helps with gas discharge.

[0038] exist Figure 2 In a preferred embodiment shown, the one-way flow member 4 includes a sealing sheet 41 and an elastic member 42.

[0039] The air duct 3 has a movable cavity 31 in the middle, and a one-way flow element 4 is installed in the movable cavity 31.

[0040] The sealing plate 41 is located at one end of the movable cavity 31 near the exhaust passage 101. The sealing plate 41 moves along the axial direction of the air guide tube 3 within the movable cavity 31 and either closes or opens the air guide tube 3.

[0041] The elastic element 42 is disposed between the sealing sheet 41 and the end of the movable cavity 31 near the air inlet 201. The two ends of the elastic element 42 are respectively connected to the sealing sheet 41 and the inner wall of the movable cavity 31. The elastic element 42 compresses and causes the sealing sheet 41 to abut against the inner wall of the movable cavity 31.

[0042] Using the above technical solution, when gas flows from the battery body 1 through the gas guide pipe 3 and into the gas storage bag 2, the sealing sheet 41 is pushed by the gas, causing the elastic element 42 to contract under force. At this time, the gas guide pipe 3 opens, and the gas flows smoothly through the gas guide pipe 3. When gas production stops, the elastic element 42 returns to its original position and pushes the sealing sheet 41 to close the gas guide pipe 3, preventing gas from flowing back from the gas storage bag 2 into the battery body 1.

[0043] exist Figure 2In a preferred embodiment shown, the sealing sheet 41 is made of rubber material to ensure a sealing effect, and the elastic element 42 is a spring that does not obstruct the passage of gas through the vent pipe 3.

[0044] exist Figure 2 In a preferred embodiment shown, the inner diameter of the movable cavity 31 is larger than the outer diameter of the sealing sheet 41, and the outer diameter of the sealing sheet 41 is larger than the inner diameter of the air guide tube 3, so that the sealing sheet 41 can move freely in the movable cavity 41 and can fully seal the air guide tube 3.

[0045] exist Figure 1 In a preferred embodiment shown, the first heat-sealing zone 11, the gas storage bag 2, and the air guide tube 3 are made of the same material. Therefore, the first heat-sealing zone 11, the gas storage bag 2, and the air guide tube 3 are all composed of two soft sheets. The soft sheets on the same side of the first heat-sealing zone 11, the gas storage bag 2, and the air guide tube 3 can be made of the same soft film, thereby improving production efficiency.

[0046] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A pouch battery, characterized by, include: The battery body (1) has at least one exhaust duct (101) thereon; An air storage bag (2) is placed outside the battery body (1) and has an air inlet (201) on it; The air duct (3) is connected at both ends to the exhaust duct (101) and the air inlet (201); A one-way flow element (4) is disposed inside the air guide pipe (3); The side of the battery body (1) with the tabs is the top of the battery body (1), and the side opposite to the top of the battery body (1) is the bottom of the battery body (1). The exhaust duct (101) is close to the top of the battery body (1). The one-way flow element (4) allows the gas in the battery body (1) to flow unidirectionally from the exhaust channel (101) to the air inlet (201) into the gas storage bag (2).

2. The pouch battery of claim 1, wherein: The battery body (1) includes, The first heat-sealing zone (11) surrounds the outer shell of the battery body (1); The cell placement area (12) is located within the first heat-sealing area (11) and forms the internal space of the battery body (1); A laminated battery cell (13) is disposed within the battery cell placement area (12); Among them, an exhaust channel (101) is opened in the first heat-sealing zone (11), and the exhaust channel (101) is connected between the cell setting area (12) and the air guide pipe (3).

3. The pouch battery of claim 2, wherein: It also includes the gas collecting tube (5), Several exhaust channels (101) are opened in parallel and spaced apart within the first heat-sealing zone (11); The gas collecting pipe (5) is located outside the battery body (1). The two ends of the gas collecting pipe (5) extend toward the top and bottom of the battery body (1) respectively and are connected to the outer ends of several exhaust channels (101). The end of the gas collecting pipe (5) facing the top of the battery body (1) is connected to the gas guide pipe (3).

4. The pouch battery of claim 2, wherein: The exhaust duct (101) is inclined from the inner end to the outer end along the bottom to the top of the soft-pack battery.

5. The pouch battery of claim 4, wherein: The exhaust duct (101) is tilted at an angle of 45° relative to the horizontal direction. 6.The soft-pack battery of claim 1, wherein: The one-way flow element (4) includes a sealing sheet (41) and an elastic element (42). The air guide tube (3) is provided with a movable cavity (31) in the middle, and a one-way flow element (4) is provided in the movable cavity (31); The sealing plate (41) is disposed at one end of the movable cavity (31) near the exhaust passage (101). The sealing plate (41) moves along the axial direction of the air guide pipe (3) within the movable cavity (31) and either closes or opens the air guide pipe (3). The elastic element (42) is disposed between the sealing sheet (41) and the end of the movable cavity (31) near the air inlet (201). The two ends of the elastic element (42) are respectively connected to the inner wall of the sealing sheet (41) and the movable cavity (31). The elastic element (42) compresses and causes the sealing sheet (41) to abut against the inner wall of the movable cavity (31).

7. The pouch battery of claim 6, wherein: The sealing sheet (41) is made of rubber material, and the elastic element (42) is a spring.

8. The pouch battery of claim 6, wherein: The inner diameter of the active cavity (31) is larger than the outer diameter of the sealing plate (41), and the outer diameter of the sealing plate (41) is larger than the inner diameter of the air guide tube (3).

9. The pouch battery of claim 2, wherein: The first heat-seal area (11), the gas storage bag (2) and the gas guide tube (3) are made of the same material.

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