Battery cell, battery device, energy storage system and electrical equipment

Abstract

A battery cell, comprising: a case, an upper cover connected to the housing, a cell assembly arranged within the housing, an explosion-proof valve located on the top cover, a first outlet structure arranged between a housing side wall of the housing and the cell assembly, and a second outlet structure located between the top cover and the cell assembly, wherein an airflow channel of the first outlet structure is connected to an airflow channel of the second outlet structure.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of energy storage, in particular a battery cell, a battery device, an energy storage system and electrical equipment. TECHNICAL BACKGROUND

[0002] In the known technology, a battery cell comprises a housing, a cell assembly, and an explosion-proof valve. The cell assembly is located inside the housing, and the explosion-proof valve is installed through the housing. If the cell assembly fails and generates gas, the pressure inside the housing increases. When the pressure exceeds a threshold of the explosion-proof valve, the gas can escape to the outside through the valve. However, gas generated at a part of the cell assembly located away from the explosion-proof valve cannot easily flow to it, so the exhaust structure of the battery cell in the known technology still requires improvement. SUMMARY

[0003] In a first aspect, embodiments of the present disclosure provide a battery cell. The battery cell comprises a housing, a top cover, a cell assembly, an explosion-proof valve, a first outlet structure, and a second outlet structure. The top cover is connected to the housing, the cell assembly is arranged within the housing, the explosion-proof valve is located on the top cover, the first outlet structure is arranged between a housing side wall and the cell assembly, the second outlet structure is arranged between the top cover and the cell assembly, and an airflow channel of the first outlet structure is connected to an airflow channel of the second outlet structure.

[0004] In one or more embodiments, the airflow channel of the first outlet structure comprises a first airflow channel and a plurality of first gas inlet openings, and the first airflow channel is connected to the plurality of first gas inlet openings.

[0005] In one or more embodiments, the first airflow channel comprises a first groove, wherein the first groove is arranged on a side of the first outlet structure facing away from the cell assembly, and the first gas inlet openings extend from a groove bottom wall of the first groove towards the cell assembly.

[0006] In one or more embodiments, the first outlet structure further comprises a first reinforcing rib and a second reinforcing rib arranged crosswise in the first groove, wherein the first reinforcing rib is provided with a first notch, the second reinforcing rib is provided with a second notch, and the first notch and the second notch are arranged crosswise at the intersection of the first reinforcing rib and the second reinforcing rib.

[0007] In one or more embodiments, the airflow channel of the first outlet structure further comprises a second groove and a plurality of first connecting openings, wherein the second groove is arranged on one side of the first outlet structure near the cell assembly and the second groove is connected to the first airflow channel through the first connecting openings.

[0008] In one or more embodiments, the battery cell further comprises an electrode pole and a connector. The electrode pole is arranged on the upper cover, the cell assembly is electrically connected to the electrode pole via the connector, and the second groove accommodates part of the connector's structure.

[0009] In one or more embodiments, the housing side wall comprises two first housing side walls arranged opposite each other, and two second housing side walls arranged opposite each other, wherein the first housing side walls intersect with the second housing side walls, wherein an area of ​​one of the first housing side walls is smaller than an area of ​​one of the second housing side walls, and wherein the first outlet structure is arranged between the first housing side wall and the cell assembly.

[0010] In one or more embodiments, the battery cell further comprises an insulating film arranged in the housing. The cell assembly and the housing side wall are separated from each other by the insulating film, and the first outlet structure and the housing side wall are also separated from each other by the insulating film.

[0011] In one or more embodiments, the airflow channel of the second outlet structure comprises a second airflow channel and a plurality of second gas inlet openings, and the second airflow channel is connected to the plurality of second gas inlet openings.

[0012] In one or more embodiments, the second airflow channel comprises a third groove, wherein the third groove is arranged on a side of the second outlet structure facing away from the cell assembly, and the second gas inlet openings extend from a groove bottom wall of the third groove towards the cell assembly.

[0013] In one or more embodiments, the second outlet structure further comprises a third reinforcing rib and a fourth reinforcing rib arranged crosswise in the third groove, wherein the third reinforcing rib is provided with a third notch, the fourth reinforcing rib is provided with a fourth notch, and the third notch and the fourth notch are arranged crosswise at the intersection of the third reinforcing rib and the fourth reinforcing rib.

[0014] In one or more embodiments, the airflow channel of the second outlet structure further comprises a fourth groove and a plurality of second connecting openings, wherein the fourth groove is arranged on one side of the second outlet structure near the cell assembly and the fourth groove is connected to the second airflow channel through the second connecting openings.

[0015] In one or more embodiments, the battery cell further comprises an electrode pole and a connector. The electrode pole is arranged on the upper cover, the cell assembly is electrically connected to the electrode pole via the connector, and the fourth groove accommodates a portion of the connector near the electrode pole.

[0016] In one or more embodiments, the first outlet structure is connected to the second outlet structure.

[0017] In one or more embodiments, a connecting structure between the first outlet structure and the second outlet structure comprises a hinge.

[0018] In one or more embodiments, the first outlet structure and the second outlet structure are arranged separately.

[0019] In one or more embodiments, the battery cell further comprises a third outlet structure. The third outlet structure is arranged between a housing bottom wall of the housing and the cell assembly, and an airflow channel of the third outlet structure is connected to the airflow channel of the second outlet structure.

[0020] In one or more embodiments, the battery cell further comprises an insulating film. The housing and the cell assembly are separated from each other by the insulating film. The third outlet structure and the cell assembly are also separated from each other by the insulating film. The insulating film comprises a first vent opening. The airflow channel of the third outlet structure includes a third airflow channel. The first vent opening is connected to the third airflow channel. A first outlet gap is formed between the insulating film and the housing side wall. The third airflow channel is connected to the airflow channel of the second outlet structure via the first outlet gap.

[0021] In one or more embodiments, the insulating film further comprises a second vent opening, the airflow channel of the third outlet structure further comprises a fourth airflow channel, the second vent opening is connected to the fourth airflow channel, a second outlet gap is formed between an edge of the third outlet structure and the housing side wall, and the fourth airflow channel is connected to the first outlet gap via the second outlet gap.

[0022] In one or more embodiments, the airflow channel of the third outlet structure is connected to the airflow channel of the first outlet structure.

[0023] In a second aspect, embodiments of the present disclosure provide a battery device. The battery device comprises a plurality of battery cells which are electrically connected to one another, and at least one of the battery cells comprises the battery cell according to the first aspect of the present disclosure.

[0024] In a third aspect, embodiments of the present disclosure provide an energy storage system. The energy storage system may comprise a battery device and a power conversion system. The battery device is electrically connected to the power conversion system, and the battery device comprises the battery device according to the second aspect of the present disclosure described above.

[0025] In a fourth aspect, embodiments of the present disclosure provide electrical equipment. The electrical equipment comprises the battery device according to the second aspect of the present disclosure described above.

[0026] In the present disclosure, if the cell assembly fails and generates gas, a portion of the gas generated on one side of the cell assembly near the housing side wall can initially flow into the airflow channel of the first outlet structure. Then, the gas can flow from the airflow channel of the first outlet structure into the airflow channel of the second outlet structure, and then the gas can flow from the airflow channel of the second outlet structure towards the explosion-proof valve. Provided that the internal pressure of the battery cell is greater than the outlet threshold of the explosion-proof valve, the gas inside the battery cell can be vented to the outside of the battery cell through the explosion-proof valve.Therefore, the battery cell of the embodiments of the present disclosure can have the advantage that "a portion of the gas generated on one side of the cell assembly near the housing side wall can be released from the battery cell to the outside in a timely manner." Accordingly, the battery cell of the embodiments of the present disclosure can have the advantage that "the risk of explosion of the battery cell is relatively low."

[0027] Since the battery device of the present disclosure includes the battery cell according to the first aspect of the present disclosure, the battery device of the present disclosure can also achieve the technical effects of the battery cell according to the first aspect of the present disclosure, which are not repeated here.

[0028] Since the energy storage system of the present disclosure includes the battery device according to the second aspect of the present disclosure, the battery device within the energy storage system is less prone to explosion.

[0029] Since the electrical equipment of the present disclosure includes the battery device according to the second aspect of the present disclosure, the battery device within the electrical equipment is less prone to explosion.

[0030] It is understood that the above general description and the detailed description below serve only to illustrate the information and cannot limit the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] To better illustrate the technical solutions in embodiments of the present disclosure, the drawings used in the description of the embodiments are briefly explained below. It is understood that the drawings described below only show some embodiments of the present disclosure and that those skilled in the art can create further drawings from these drawings without any creative effort. Fig. Figure 1 is a perspective schematic structural representation of a battery cell according to one or more embodiments; Fig. 2 is a side view of the Fig. 1 battery cell shown; Fig. 3 is an exploded view of a battery cell according to one or more embodiments; Fig. 4 is a cross-sectional view of the in Fig. 2 battery cells shown along one direction AA; Fig. Figure 5 is a structural schematic cross-sectional representation of a cell assembly and a first outlet structure according to one or more embodiments; Fig. Figure 6 is a schematic structural representation of a first outlet structure according to one or more embodiments; Fig. Figure 7 is a schematic structural representation of a first outlet structure according to one or more embodiments; Fig. 8 is a partially enlarged schematic representation of a Fig. Section B shown in section 7; Fig. Figure 9 is a schematic structural representation of a first outlet structure according to one or more embodiments; Fig. Figure 10 is a schematic structural representation of a first outlet structure according to one or more embodiments; Fig. Figure 11 is a schematic structural representation of a first outlet structure and a connecting piece according to one or more embodiments; Fig. Figure 12 is a schematic structural representation of an insulating film according to one or more embodiments; Fig. Figure 13 is a schematic structural representation of a housing, a cell assembly and a first outlet structure from a top view; Fig. Figure 14 is a schematic cross-sectional representation of a substructure of a cell assembly and a second outlet structure according to one or more embodiments; Fig. Figure 15 is a schematic structural representation of a second outlet structure according to one or more embodiments; Fig. Figure 16 is a schematic structural representation of a second outlet structure according to one or more embodiments; Fig. Figure 17 is a partially enlarged schematic representation of a Fig. Section C shown in section 16; Fig. Figure 18 is a schematic structural representation of a second outlet structure according to one or more embodiments; Fig. Figure 19 is a schematic structural representation of a second outlet structure according to one or more embodiments; Fig. Figure 20 is a schematic structural representation of a second outlet structure and a connecting piece according to one or more embodiments; Fig. Figure 21 is a partially schematic structural representation of a first outlet structure, a second outlet structure and a hinge according to one or more embodiments; Fig. 22 is a partially schematic structural representation of a housing, a cell assembly, a first outlet structure and a third outlet structure according to one or more embodiments; Fig. 23 is a schematic structural representation of a third outlet structure according to one or more embodiments; Fig. 24 is a partially schematic structural representation of an insulating film and a third outlet structure according to one or more embodiments; Fig. Figure 25 is a schematic cross-sectional representation of a substructure of a battery cell according to one or more embodiments; Fig. Figure 26 is a schematic cross-sectional representation of a substructure of a battery cell according to one or more embodiments; Fig. 27 is a partially schematic structural representation of a first outlet structure according to one or more embodiments; and Fig. Figure 28 is a partially schematic structural representation of an insulating film and a third outlet structure according to one or more embodiments.

[0032] Reference symbols: 10 - battery cell, 1a - housing, 11 - housing side wall, 111 - first housing side wall, 112 - second housing side wall, 12 - housing bottom wall, 13 - housing receiving space, 1b - top cover, 2 - cell assembly, 3 - explosion-proof valve, 4 - first outlet structure, 4a - hinge, 41 - first airflow channel, 411 - first groove, 412 - outlet, 42 - first gas inlet opening, 43 - first reinforcing rib, 431 - first notch, 44 - second reinforcing rib, 441 - second notch, 45 - second groove, 46 - first connecting opening, 47 - third connecting opening, 5 - second outlet structure, 51 - second airflow channel, 511 - third groove, 512 - inlet, 52 - second gas inlet opening, 53 - third Reinforcing rib, 531 - third notch, 54 - fourth reinforcing rib, 541 - fourth notch, 55 - fourth groove, 56 - second connecting opening, 57 - through opening, 6 - electrode pole, 7 - connector, 71 - first section, 72 - second section, 8 - insulating foil,8a - first outlet gap, 81 - first vent opening, 82 - second vent opening, 83 - foil receiving cavity, 84 - foil opening, 85 - fourth connecting opening, 9 - third outlet structure, 9a - second outlet gap, 91 - third airflow channel, 92 - fourth airflow channel. DESCRIPTION OF THE EXECUTION FORMS

[0033] To better understand the technical solutions of this disclosure, embodiments of this disclosure are described in detail below with reference to the drawings. It should be noted that the described embodiments represent only some, and not all, embodiments of this disclosure.

[0034] The terms used in the embodiments of this disclosure serve only to describe specific embodiments and are not intended to limit the present disclosure. As used in the embodiments of this disclosure and the appended claims, the singular forms "a / an", "the", and "the" also include the plural forms unless the context clearly indicates otherwise.

[0035] It is understood that the term "and / or" used here merely describes an associative relationship that denotes an associated object, with three relationships being possible, for example, A and / or B, which can mean: only A, both A and B, or only B. Furthermore, the symbol " / " here generally indicates that the related objects before and after the symbol represent an "or" relationship. Additionally, the ordering terms used here, such as "first," "second," "third," "fourth," "fifth," and "sixth," serve only to avoid confusion between the components and are not necessarily to be understood as quantitative limitations.

[0036] In the drawings, the thicknesses of elements, layers, films, plates, areas, etc., are exaggerated for clarity. The same reference symbols throughout the description denote the same elements. It is understood that when an element such as a layer, film, area, or substrate is described as "on" another element, it may be located directly on top of that element, or there may be intermediate elements. Conversely, when an element is described as being "directly on" another element, there are no intermediate elements.

[0037] In the drawings, two of the directions up-down, left-right, and front-back are perpendicular to each other. The up-down direction can be understood as the first direction, the left-right direction as the second, the front-back direction as the third, and the up-down direction can also be referred to as the vertical direction.

[0038] In a first aspect, the present disclosure provides several embodiments of a battery cell relating to the technical field of energy storage. In some embodiments, the battery cell can be referred to as a secondary battery, rechargeable battery, or storage battery. A secondary battery refers to a battery that, after being discharged, can store electrical energy again by recharging the active substances it contains.

[0039] In some embodiments, the battery cell 10 can be described with reference to Fig. 1 and Fig. 2 comprising a housing 1a and a top cover 1b, which are connected to each other. With reference to Fig. 3 and Fig. The battery cell 10 can further comprise a cell assembly 2, an explosion-proof valve 3, a first outlet structure 4, and a second outlet structure 5. The housing 1a can have a housing receiving space 13. The cell assembly 2 can be arranged in the housing receiving space 13 of the housing 1a. The explosion-proof valve 3 can be arranged on the top cover 1b. The first outlet structure 4 can be arranged between a housing side wall 11 of the housing 1a and the cell assembly 2. The second outlet structure 5 can be arranged between the top cover 1b and the cell assembly 2. An airflow channel of the first outlet structure 4 is connected to an airflow channel of the second outlet structure 5. Both the airflow channel of the first outlet structure 4 and the airflow channel of the second outlet structure 5 are configured for gas discharge.

[0040] In such an arrangement, if the cell assembly 2 fails (e.g., due to overcharging, excessive temperature, internal short circuit of the cell, over-discharging, structural damage, or electrolyte decomposition within the cell) and gas is generated as a result, the internal pressure of the battery cell 10 increases and exceeds a discharge threshold of the explosion-proof valve 3. The gas generated inside the battery cell 10 can be released to the outside of the battery cell 10 through the explosion-proof valve 3 to reduce the internal pressure of the battery cell 10 and thus reduce the risk of explosion of the battery cell 10.Although the distance between one side of the cell assembly 2 near the housing side wall 11 and the explosion-proof valve 3 located on the upper cover 1b is greater than the distance between the top of the cell assembly 2 near the upper cover 1b and the explosion-proof valve 3, some of the gas generated on the side of the cell assembly 2 near the housing side wall 11 can initially flow into the airflow channel of the first outlet structure 4. Subsequently, the gas can flow from the airflow channel of the first outlet structure 4 into the airflow channel of the second outlet structure 5 and then from the airflow channel of the second outlet structure 5 to the explosion-proof valve 3, allowing the gas to be discharged from the battery cell 10 to the outside through the explosion-proof valve 3.Therefore, some embodiments of the battery cell 10 of the present disclosure may have the advantage that "a portion of the gas that forms on the side of the cell assembly 2 near the housing side wall 11 can be vented out of the battery cell 10 in a timely manner." Similarly, some embodiments of the battery cell 10 of the present disclosure may have the advantage that "the explosion risk of the battery cell 10 is relatively low."

[0041] In some embodiments, the solution relating to "the airflow channel of the first outlet structure 4 is connected to the airflow channel of the second outlet structure 5" may comprise the following three connection solutions: In one connection solution, the airflow channel of the first outlet structure 4 is directly connected to the airflow channel of the second outlet structure 5, allowing gas to flow from the airflow channel of the first outlet structure 4 into the airflow channel of the second outlet structure 5. In another connection solution, the airflow channel of the first outlet structure 4 and the airflow channel of the second outlet structure 5 may be indirectly connected via other airflow channels, allowing gas to flow from the airflow channel of the first outlet structure 4 into the airflow channel of the second outlet structure 5.In another connection solution, the airflow channel of the first outlet structure 4 can be connected neither directly nor indirectly to the airflow channel of the second outlet structure 5, but the outlet of the airflow channel of the first outlet structure 4 can be connected indirectly to the inlet of the airflow channel of the second outlet structure 5 via a connecting space, so that gas can flow from the airflow channel of the first outlet structure 4 into the airflow channel of the second outlet structure 5.

[0042] In some embodiments, with reference to Fig. 5, the airflow channel of the first outlet structure 4 can comprise a first airflow channel 41 and a plurality of first gas inlet openings 42, and the first airflow channel 41 is connected to the plurality of first gas inlet openings 42. The gas generated from the side of the cell assembly 2 near the housing side wall 11 can first enter the first airflow channel 41 through the first gas inlet openings 42, and then the gas can converge in the first airflow channel 41 and flow into the airflow channel of the second outlet structure 5.

[0043] In some embodiments, with reference to Fig. 5, the first gas inlet openings 42 can be arranged at intervals along the top-bottom direction on one side of the first outlet structure 4 facing the cell assembly 2.

[0044] In some embodiments, the first gas inlet openings 42 can also be arranged at intervals along the front-back direction on the side of the first outlet structure 4 facing the cell assembly 2.

[0045] In some embodiments, the shape of the first gas inlet opening 42 can be a circle, a rectangle, a triangle, an ellipse or a polygon.

[0046] In some embodiments, the shape of the first gas inlet opening 42 may not be restricted.

[0047] In some embodiments, the cross-sectional area of ​​the first airflow channel 41 can increase along a bottom-to-top direction. This can also be understood to mean that the cross-sectional area of ​​a section of the first airflow channel 41 closer to the upper cover 1b is larger, or that the cross-sectional area of ​​a section of the first airflow channel 41 closer to the second outlet structure 5 is larger, so that gas near the middle upper section of the first outlet structure 4 can efficiently enter the first airflow channel 41.

[0048] In some embodiments, with reference to Fig. 5, the cross-sectional area of ​​the first airflow channel 41 can remain unchanged along the direction from bottom to top.

[0049] In some embodiments, with reference to Fig. 5, both opposite sides (for example, the left and the right side) of the cell assembly 2 can be provided with the first outlet structure 4. The airflow channels of the first outlet structure 4, which are arranged on both sides of the cell assembly 2, can be connected to the airflow channel of the second outlet structure 5, which is arranged above the cell assembly 2.

[0050] In some embodiments, the first airflow channel 41 may include a hole structure, a groove structure or other flow-guiding structures that have functions for receiving gas and guiding the gas flow.

[0051] In some embodiments, with reference to the in Fig. 4 and Fig. 5 first outlet structure 4 shown, which is located on the left side of the cell assembly 2, and with reference to Fig. 6, the first airflow channel 41 includes a first groove 411 located on the left side of the first outlet structure 4, facing away from the cell assembly 2. First gas inlet openings 42 can extend from a groove bottom wall of the first groove 411 towards the cell assembly 2. In such an arrangement, gas generated on the left side of the cell assembly 2 can enter the first groove 411 through the first gas inlet openings 42.

[0052] Similarly, for the first outlet structure 4, which is on the right side of the in Fig. 4 and Fig. The first airflow channel 41, as shown in Figure 5, is also provided with a first groove 411 in the cell assembly 2. The first groove 411 can be located on the right side of the first outlet structure 4, which is located on the right side of the cell assembly 2 facing away from the cell assembly 2. The first gas inlet openings 42 can extend from the bottom wall of the first groove 411 towards the cell assembly 2.

[0053] In some embodiments, with reference to Fig. 6, the first gas inlet openings 42 can be arranged at intervals on the groove bottom wall of the first groove 411 along the top-bottom direction and the front-back direction.

[0054] In some embodiments, the ratio of the sum of the total flow cross-sectional areas of the first gas inlet openings 42 to the area of ​​the groove bottom wall of the first groove 411 may be in a range of 0.005 to 0.1, where the value may be, for example, 0.005, 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, 0.055, 0.06, 0.065, 0.07, 0.075, 0.08, 0.085, 0.09, 0.095 or 0.1.

[0055] In some embodiments, the ratio of the sum of the total flow cross-sectional areas of the first gas inlet openings 42 to the area of ​​the groove bottom wall of the first groove 411 can also be in a range of 0.1 to 0.2, where the value can be, for example, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19 or 0.2.

[0056] In some embodiments, with reference to Fig. 6, the first groove 411 can be connected to the outlet 412, and the outlet 412 can be arranged on the top of the first groove 411, so that gas in the first groove 411 can flow through the outlet 412 to the second outlet structure 5.

[0057] In some embodiments, the first outlet structure 4 can be described by reference to Fig. 7 further comprising a first reinforcing rib 43 and a second reinforcing rib 44, wherein the first reinforcing rib 43 and the second reinforcing rib 44 may be arranged crosswise in the first groove 411. In such an arrangement, the first reinforcing rib 43 and the second reinforcing rib 44 can impart a relatively greater structural strength to the first outlet structure 4. Although the space for the gas flow in the first groove 411 is subdivided into several sub-spaces by the first reinforcing rib 43 and the second reinforcing rib 44, the first reinforcing rib 43 can be, with reference to Fig. 8 may be provided with a first notch 431, and the second reinforcing rib 44 may be provided with a second notch 441. The first notch 431 and the second notch 441 are arranged crosswise at the intersection of the first reinforcing rib 43 and the second reinforcing rib 44. A portion of the gas may flow along the in Fig. Arrow L1, as shown in section 8, flows from one sub-space to another, and another portion of the gas can flow along the path shown in Fig. The gas flows from one sub-space to another, as indicated by arrow L2 in Figure 8. The general flow direction of the gas in the first groove 411 is still oriented such that the gas flows in the first groove 411 towards the airflow channel of the second outlet structure 5. During the process of the gas flowing along the first groove 411, new gas continuously enters the first groove 411, so that the flow velocity of the gas in the first groove 411 gradually increases. The first reinforcing rib 43 and the second reinforcing rib 44 have a certain blocking effect, so that the increase in the flow velocity of the gas in the first groove 411 per unit time is relatively small, and the gas does not tend to flow through the explosion-proof valve 3 to the outside of the battery cell 10 under conditions of excessively high flow velocity.This reduces the possibility that “other structures outside the battery cell 10 may be affected and damaged by the high-speed gas escaping from the explosion-proof valve 3”.

[0058] In some embodiments, with reference to Fig. 7 and Fig. 8, the first groove 411 can be provided with a first reinforcing rib 43 extending along the top-bottom direction, and the first reinforcing rib 43 can be provided with at least two first notches 431 arranged at intervals along the top-bottom direction.

[0059] In some embodiments, with reference to Fig. 7 and Fig. 8, the sum of the flow cross-sectional areas of the first notches 431 of the same first reinforcing rib 43, when viewed along the front-back direction, can be in a region of 3 square millimeters (mm²). 2 ) to 100 square millimeters (mm 2) lie, for example the value can be 3 mm 2 , 5 mm 2 , 10 mm 2 , 20 mm 2 , 30 mm 2 , 40 mm 2 , 50 mm 2 , 60 mm 2 , 70 mm 2 , 80 mm 2 , 90 mm 2 or 100 mm 2 be.

[0060] In some embodiments (not shown in the drawings), the first groove may be provided with at least two first reinforcing ribs extending along the top-bottom direction. The at least two first reinforcing ribs are arranged at intervals along the front-back direction, and the same first reinforcing rib may be provided with at least two first notches arranged at intervals along the top-bottom direction.

[0061] In some embodiments (not shown in the drawings) the first notch on the first reinforcing rib can be replaced by a hole structure.

[0062] In some embodiments, with reference to Fig. 7 and Fig. 8, the first groove 411 can be provided with at least two second reinforcing ribs 44 extending along the front-back direction. The at least two second reinforcing ribs 44 are arranged at intervals along the top-bottom direction, and the same second reinforcing rib 44 can be provided with a second notch 441.

[0063] In some embodiments, with reference to Fig. 7 and Fig. 8, the sum of the flow cross-sectional areas of the second notches 441 of the same second reinforcing rib 44, when viewed along the top-bottom direction, can be in a region of 3 square millimeters (mm²). 2 ) to 100 square millimeters (mm 2 ) lie, for example the value can be 3 mm 2 , 5 mm 2 , 10 mm 2 , 20 mm 2 , 30 mm 2 , 40 mm 2 , 50 mm 2 , 60 mm2 , 70 mm 2 , 80 mm 2 , 90 mm 2 or 100 mm 2 be.

[0064] In some embodiments (not shown in the drawings) the first groove may be provided with a second reinforcing rib extending along the front-back direction, and the second reinforcing rib may be provided with at least two second notches spaced apart along the front-back direction.

[0065] In some embodiments (not shown in the drawings) the second notch on the second reinforcing rib can be replaced by a hole structure.

[0066] In some embodiments, with reference to Fig. 9 and Fig. 10, wherein the first outlet structure 4 is on the left side of the in Fig. 4 and Fig. Taking as an example the cell assembly 2 shown in Figure 5, the airflow channel of the first outlet structure 4 further comprises a second groove 45 and a plurality of first connecting openings 46. The second groove 45 can be located on the right side of the first outlet structure 4, near the cell assembly 2. The second groove 45 can be connected to the first airflow channel 41 via the first connecting openings 46, or the second groove 45 can be connected to the first groove 411 via the first connecting openings 46. In such an arrangement, the gas generated on the left side of the cell assembly 2 can also initially enter the second groove 45, and subsequently, the gas from the second groove 45 can enter the first airflow channel 41 or the first groove 411 through the first connecting openings 46.

[0067] Similarly, for the first outlet structure 4, which is on the right side of the in Fig. 4 and Fig. The cell assembly 2 shown in Figure 5 is arranged, the first airflow channel 41 of which also includes a second groove 45 and a plurality of first connecting openings 46. The second groove 45 can be located on the right side of the first outlet structure 4, which is located on the right side of the cell assembly 2, close to the cell assembly 2. The second groove 45 can be connected to the first airflow channel 41 via the first connecting openings 46, or the second groove 45 can be connected to the first groove 411 via the first connecting openings 46.

[0068] In some embodiments, such as in Fig. As shown in Figure 9, the first connecting openings 46 can be arranged at intervals on the groove side wall of the second groove 45 along the top-bottom direction.

[0069] In some embodiments, with reference to Fig. 1 to Fig. 3. The battery cell 10 may further comprise an electrode pole 6. The electrode pole 6 is arranged on the upper cover 1b and configured to be electrically connected to a circuit outside the battery cell 10.

[0070] In some embodiments, with reference to Fig. 1 to Fig. 3, the battery cell 10 may further comprise a connecting piece 7, as shown in Fig. 11 shown.

[0071] In some embodiments, the cell assembly 2 can be connected to the electrode pole 6 via the connecting piece 7, so that the cell assembly 2 can receive electrical energy from a circuit outside the battery cell 10 or the cell assembly 2 can supply electrical energy to a circuit outside the battery cell 10.

[0072] In some embodiments, the second groove 45 can be defined with reference to Fig. 7 incorporate part of the structure of the connecting piece 7. In such an arrangement, the battery cell 10 has the advantage of relatively high structural compactness.

[0073] In some embodiments, with reference to Fig. 7, the connecting piece 7 can comprise a first section 71 and a second section 72, which are connected to each other. The extension direction of the first section 71 intersects the extension direction of the second section 72. The first section 71 can be arranged in the second groove 45, and the second section 72 can be arranged between the cell assembly 2 and the second outlet structure 5.

[0074] In some embodiments (not shown in the drawings), the battery cell may further include an adhesive. The first section of the connector can be attached to the side of the cell assembly by the adhesive. At least part of the adhesive structure may be arranged in the second groove.

[0075] In some embodiments (not shown in the drawings), the airflow channel of the first outlet structure may mainly comprise a groove, and the groove may be located on one side of the first outlet structure near the cell assembly. One end of the groove near the top cover is an outlet. Gas generated at the side of the cell assembly can enter the groove directly, and then the gas in the groove can flow through the outlet into the airflow channel of the second outlet structure.

[0076] In some embodiments, with reference to Fig. 1 to Fig. 3. The housing side wall 11 can comprise two first housing side walls 111, arranged opposite each other in a left-right direction, and two second housing side walls 112, arranged opposite each other in a front-back direction. The first housing side wall 111 can intersect the second housing side wall 112. The area of ​​a first housing side wall 111 can be smaller than the area of ​​a second housing side wall 112. The first outlet structure 4 can be arranged between the first housing side wall 111 and the cell assembly 2.

[0077] In some embodiments (not shown in the drawings), the housing side wall can comprise two first housing side walls arranged opposite each other in the left-right direction, and two second housing side walls arranged opposite each other in the front-back direction. The first housing side wall can intersect the second housing side wall. The area of ​​a first housing side wall can be larger than the area of ​​a second housing side wall. The first outlet structure can be arranged between the first housing side wall and the cell assembly.

[0078] In some embodiments (not shown in the drawings), the housing side wall can comprise two first housing side walls arranged opposite each other in the left-right direction, and two second housing side walls arranged opposite each other in the front-back direction. The first housing side wall can intersect with the second housing side wall. The area of ​​a first housing side wall can be equal to the area of ​​a second housing side wall. The first outlet structure can be arranged between the first housing side wall and the cell assembly, or the first outlet structure can be arranged between the second housing side wall and the cell assembly.

[0079] In some embodiments (not shown in the drawings), the housing side wall can comprise two first housing side walls facing each other in the left-right direction and two second housing side walls facing each other in the front-back direction. The first housing side wall can intersect the second housing side wall. Regardless of the size ratio between the area of ​​the first housing side wall and the area of ​​the second housing side wall, the first outlet structure can be located between the first housing side wall and the cell assembly, and the first outlet structure can also be located between the second housing side wall and the cell assembly.

[0080] In some embodiments, with reference to Fig. 12 and Fig. 13, the battery cell 10 can further comprise an insulating film 8 arranged in the housing 1a. The cell assembly 2 and the housing side wall 11 are separated from each other by the insulating film 8, and the first outlet structure 4 and the housing side wall 11 are separated from each other by the insulating film 8.

[0081] In some embodiments, with reference to Fig. 12, the insulating film 8 can be provided with a film receiving chamber 83 and a film opening 84. The cell assembly 2 and the first outlet structure 4 can be fed into the film receiving chamber 83 through the film opening 84.

[0082] In some embodiments, with reference to Fig. 13, the first outlet structure 4 and the first housing side wall 111 are separated from each other by a relatively small area by the insulating film 8.

[0083] In some embodiments, the insulating film 8 can also be referred to as a Mylar film. The insulating film 8 is configured to electrically insulate the cell assembly 2 and the housing side wall 11.

[0084] In some embodiments, the insulating film 8 can cover the first groove 411. A gap is formed between the insulating film 8 and the bottom wall of the first groove 411 in the left-right direction. The insulating film 8 allows gas to flow efficiently in the first groove 411 in a bottom-to-top direction, so that the gas in the first groove 411 flows efficiently into the airflow channel of the second outlet structure 5.

[0085] In some embodiments, the material of the first outlet structure 4 can be an insulating material, so that the first outlet structure 4 can serve as an insulating element with an electrical insulating function.

[0086] In some embodiments, the material of the first outlet structure 4 can be a plastic material with an electrical insulating function, such as polypropylene (PP), polyethylene (PE), polyamide (PA) or other materials with an electrical insulating function.

[0087] In some embodiments, the material of the first outlet structure 4 can be a ceramic material, so that the first outlet structure 4 has an electrical insulating function.

[0088] In some embodiments, the airflow channel of the second outlet structure 5 can be described with reference to Fig. 14 comprising a second airflow channel 51 and a plurality of second gas inlet openings 52, the second airflow channel 51 being connected to the plurality of second gas inlet openings 52. A portion of the gas generated from the top of the cell assembly 2 near the top cover 1b can first enter the second airflow channel 51 through the second gas inlet openings 52, then the gas can converge in the second airflow channel 51 and flow towards the explosion-proof valve 3, and then the gas is discharged through the explosion-proof valve 3 to the outside of the battery cell 10.

[0089] In some embodiments, with reference to Fig. 14, the second airflow channel 51 can have an inlet 512. The inlet 512 is located at one end of the second airflow channel 51, facing away from the explosion-proof valve 3, and the inlet 512 can be connected to the airflow channel of the first outlet structure 4, so that gas in the airflow channel of the first outlet structure 4 can enter the second airflow channel 51, allowing the gas to flow through the second airflow channel 51 towards the explosion-proof valve 3.

[0090] In some embodiments, with reference to Fig. 14, the second gas inlet openings 52 can be arranged at intervals along the left-right direction on one side of the second outlet structure 5 facing the cell assembly 2.

[0091] In some embodiments, the second gas inlet openings 52 can be arranged at intervals along the front-back direction on the side of the second outlet structure 5 facing the cell assembly 2.

[0092] In some embodiments, the shape of the second gas inlet opening 52 can be a circle, a rectangle, a triangle, an ellipse or a polygon.

[0093] In some embodiments, the shape of the second gas inlet opening 52 may not be restricted.

[0094] In some embodiments, the flow cross-sectional area of ​​the section of the second airflow channel 51 that is closer to the explosion-proof valve 3 is larger, so that gas near the section of the second outlet structure 5 that is close to the explosion-proof valve 3 can efficiently enter the second airflow channel 51.

[0095] In some embodiments, with reference to Fig. 14, the cross-sectional area of ​​the second airflow channel 51 can remain unchanged along the left-right direction.

[0096] In some embodiments, the battery cell 10 can comprise two secondary outlet structures 5 arranged opposite each other along the left-right direction. The airflow channel of the second outlet structure 5 on the left is connected to the airflow channel of the first outlet structure 4 on the left. The airflow channel of the second outlet structure 5 on the right is connected to the airflow channel of the first outlet structure 4 on the right. The airflow channels of both secondary outlet structures 5 extend toward the explosion-proof valve 3.

[0097] In some embodiments, the second airflow channel 51 may have a hole structure, a groove structure or other flow-guiding structures that have functions for receiving gas and guiding the gas flow.

[0098] In some embodiments, the second airflow channel 51 can be described with reference to Fig. 15 comprising a third groove 511, which is arranged on the upper side of the second outlet structure 5, facing away from the cell assembly 2. The second gas inlet openings 52 can extend from the bottom wall of the third groove 511 towards the cell assembly 2. In such an arrangement, the gas generated at the upper side of the cell assembly 2 can enter the third groove 511 through the second gas inlet openings 52.

[0099] In some embodiments, with reference to Fig. 15, the second gas inlet openings 52 can be arranged at intervals on the groove bottom wall of the third groove 511 along the left-right direction and the front-back direction.

[0100] In some embodiments, the ratio of the sum of the total flow cross-sectional areas of the second gas inlet openings 52 to the area of ​​the groove bottom wall of the third groove 511 can be in a range of 0.005 to 0.1, for example the value can be 0.005, 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, 0.055, 0.06, 0.065, 0.07, 0.075, 0.08, 0.085, 0.09, 0.095 or 0.1.

[0101] In some embodiments, the ratio of the sum of the total flow cross-sectional areas of the second gas inlet openings 52 to the area of ​​the groove bottom wall of the third groove 511 can also be in a range of 0.1 to 0.2, for example the value can be 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19 or 0.2.

[0102] In some embodiments, with reference to Fig. 15, the third groove 511 can be connected to the inlet 512. The inlet 512 is located at one end of the third groove 511 facing away from the explosion-proof valve 3, and at the other end of the third groove 511 that is close to the first outlet structure 4. The gas in the airflow channel of the first outlet structure 4 can enter the third groove 511 through the inlet 512.

[0103] In some embodiments, with reference to Fig. 16, the second outlet structure 5 can further comprise a third reinforcing rib 53 and a fourth reinforcing rib 54, and the third reinforcing rib 53 and the fourth reinforcing rib 54 are arranged crosswise in the third groove 511. In such an arrangement, the third reinforcing rib 53 and the fourth reinforcing rib 54 can impart a relatively greater structural strength to the second outlet structure 5. Although the space for gas flow in the third groove 511 is subdivided into several sub-spaces by the third reinforcing rib 53 and the fourth reinforcing rib 54, the third reinforcing rib 53 can be provided with a third notch 531, as shown in Fig. 17 shown, and the fourth reinforcing rib 54 can be provided with a fourth notch 541, as in Fig. Figure 17 shows the third notch 531 and the fourth notch 541 arranged crosswise at the intersection of the third reinforcing rib 53 and the fourth reinforcing rib 54. Gas can flow along the in Fig. Arrow L3, as shown in section 17, flows from one sub-chamber to another, and some of the gas can flow along the path shown in Fig. The gas flows from one sub-chamber to another, as shown by arrow L4 in Figure 17. The general flow direction of the gas in the third groove 511 remains such that the gas flows in the direction of the explosion-proof valve 3. During the process of the gas flowing along the third groove 511, new gas continuously enters the third groove 511, so that the flow velocity of the gas in the third groove 511 gradually increases.The third reinforcing rib 53 and the fourth reinforcing rib 54 have a certain blocking effect, so that the increase in the flow velocity of the gas in the third groove 511 per unit time is relatively small and the gas does not tend to flow through the explosion-proof valve 3 to the outside of the battery cell 10 under the condition of an excessively high flow velocity. This reduces the possibility that “other structures outside the battery cell 10 may be affected and damaged by the high-speed gas escaping from the explosion-proof valve 3”.

[0104] In some embodiments, with reference to Fig. 16 and Fig. 17, the third groove 511 can be provided with at least two third reinforcing ribs 53 extending along the left-right direction. The at least two third reinforcing ribs 53 are arranged at intervals along the front-back direction, and the same third reinforcing rib 53 can be provided with at least two third notches 531 arranged at intervals along the left-right direction.

[0105] In some embodiments, with reference to Fig. 16 and Fig. 17, the sum of the flow cross-sectional areas of the third notches 531 of the same third reinforcing rib 53, when viewed in the front-back direction, can be in an area of ​​3 square millimeters (mm²). 2 ) to 100 square millimeters (mm 2 ) lie, for example the value can be 3 mm 2 , 5 mm 2 , 10 mm 2 , 20 mm 2 , 30 mm 2 , 40 mm 2 , 50 mm 2 , 60 mm 2, 70 mm 2 , 80 mm 2 , 90 mm 2 or 100 mm 2 be.

[0106] In some embodiments (not shown in the drawings) the third groove may be provided with a third reinforcing rib extending along the left-right direction, and the third reinforcing rib may be provided with at least two third notches arranged at intervals along the left-right direction.

[0107] In some embodiments (not shown in the drawings) the third notch on the third reinforcing rib can be replaced by a hole structure.

[0108] In some embodiments, with reference to Fig. 16 and Fig. 17, the third groove 511 can be provided with at least two fourth reinforcing ribs 54 extending along the front-back direction. The at least two fourth reinforcing ribs 54 are arranged at intervals along the left-right direction, and the same fourth reinforcing rib 54 can be provided with at least two fourth notches 541 arranged at intervals along the front-back direction.

[0109] In some embodiments, with reference to Fig. 16 and Fig. 17, the sum of the flow cross-sectional areas of the fourth notches 541 of the same fourth reinforcing rib 54, when viewed along the left-right direction, can be in a region of 3 square millimeters (mm²). 2 ) to 100 square millimeters (mm 2 ) lie, for example the value can be 3 mm 2 , 5 mm 2 , 10 mm 2 , 20 mm 2 , 30 mm 2 , 40 mm 2 , 50 mm 2 , 60 mm2 , 70 mm 2 , 80 mm 2 , 90 mm 2 or 100 mm 2 be.

[0110] In some embodiments (not shown in the drawings) the third groove may be provided with a fourth reinforcing rib extending along the front-back direction, and the fourth reinforcing rib may be provided with at least two fourth notches spaced at intervals along the front-back direction.

[0111] In some embodiments (not shown in the drawings) the fourth notch on the fourth reinforcing rib can be replaced by a hole structure.

[0112] In some embodiments, with reference to Fig. 18 to Fig. 19. The airflow channel of the second outlet structure 5 can further comprise a fourth groove 55 and a plurality of second connecting openings 56. The fourth groove 55 can be located on the underside of the second outlet structure 5 near the cell assembly 2. The fourth groove 55 can be connected to the second airflow channel 51 via the second connecting opening 56, or the fourth groove 55 can be connected to the third groove 511 via the second connecting opening 56. In such an arrangement, the gas generated at the top of the cell assembly 2 can also first enter the fourth groove 55 and then exit the fourth groove 55 through the second connecting opening 56 into the second airflow channel 51 or the third groove 511.

[0113] In some embodiments, with reference to Fig. 18, the second connecting openings 56 can be arranged at intervals on the groove side wall of the fourth groove 55 along the left-right direction.

[0114] In some embodiments, with reference to Fig. 20, the fourth groove 55 can accommodate part of the structure of the connecting piece 7. In such an arrangement, the battery cell 10 has the advantage of relatively high structural compactness.

[0115] In some embodiments, with reference to Fig. 20, the connecting piece 7 can comprise a first section 71 and a second section 72, which are connected to each other. The direction of extension of the first section 71 intersects the direction of extension of the second section 72. The first section 71 can be arranged between the cell assembly 2 and the first outlet structure 4, and the second section 72 can be arranged in the fourth groove 55.

[0116] In some embodiments (not shown in the drawings), the battery cell may further include an adhesive. The second section of the connector can be attached to the top of the cell assembly by the adhesive. At least part of the adhesive may be arranged in the first groove.

[0117] In some embodiments, with reference to Fig. 18 and Fig. 19, the groove bottom wall of the fourth groove 55 can be provided with a through-opening 57 that extends along the top-bottom direction through the second outlet structure 5. The electrical connection structure between the electrode pole 6 and the second section 72 can pass through the through-opening 57.

[0118] In some embodiments, the second groove 45 of the first outlet structure 4 can be connected to the fourth groove 55 of the second outlet structure 5. The gas generated at the side of the cell assembly 2 can first enter the second groove 45, then the gas flows from the second groove 45 into the fourth groove 55, then the gas flows from the fourth groove 55 through the second connecting opening 56 into the third groove 511, and then the gas flows from the third groove 511 towards the explosion-proof valve 3.

[0119] In some embodiments, the material of the second outlet structure 5 can be an insulating material, so that the second outlet structure 5 can serve as an insulating element with an electrical insulating function.

[0120] In some embodiments, the material of the second outlet structure 5 can be a plastic material with an electrical insulating function, such as polypropylene, polyethylene, polyamide or other materials with an electrical insulating function.

[0121] In some embodiments, the material of the second outlet structure 5 can be a ceramic material, so that the second outlet structure 5 has an electrical insulating function.

[0122] In some embodiments (not shown in the drawings), the airflow channel of the second outlet structure may mainly comprise a groove, and the groove may be located on the underside of the second outlet structure near the cell assembly. One end of the groove facing away from the explosion-proof valve is an inlet, and one end of the groove near the first outlet structure is an inlet. The gas generated at the top of the cell assembly can enter the groove directly, the gas in the airflow channel of the first outlet structure can enter the groove through the inlet, and then the gas can flow in the groove towards the explosion-proof valve.

[0123] In some embodiments (not shown in the drawings), the airflow duct of the second outlet structure may comprise an upper airflow duct and a lower airflow duct, with the upper airflow duct being located above the lower airflow duct. The upper airflow duct is closer to the upper cover than the lower airflow duct, and the lower airflow duct is closer to the top of the cell assembly than the upper airflow duct. The airflow duct of the first outlet structure may be connected to the upper airflow duct. Gas in the airflow duct of the first outlet structure may enter the upper airflow duct, and the gas in the upper airflow duct may flow toward the explosion-proof valve.The gas generated at the top of the cell assembly near the upper cover can enter the lower airflow channel, and the gas in the lower airflow channel can flow towards the explosion-proof valve. It can also be understood that in the same second outlet structure, the upper airflow channel and the lower airflow channel are two parallel structures designed to direct gas towards the explosion-proof valve.

[0124] In some embodiments, with reference to Fig. 21, the first outlet structure 4 can be connected to the second outlet structure 5.

[0125] In some embodiments, when the first outlet structure 4 is connected to the second outlet structure 5, the airflow channel of the first outlet structure 4 may be connected directly or indirectly to the airflow channel of the second outlet structure 5.

[0126] In some embodiments, when the first outlet structure 4 is connected to the second outlet structure 5, the airflow channel of the first outlet structure 4 and the airflow channel of the second outlet structure 5 may not be connected, but may be interconnected.

[0127] In some embodiments, the connecting structure between the first outlet structure 4 and the second outlet structure 5 may include a hinge 4a, as shown in Fig. Figure 21 shows that in such an arrangement the first outlet structure 4 can rotate relative to the second outlet structure 5 along the direction K during the assembly or disassembly process, thus facilitating assembly or disassembly.

[0128] In some embodiments, with reference to Fig. 21, the first outlet structure 4, the second outlet structure 5, and the hinge 4a can be injection-molded in one piece. The hinge 4a has a relatively small thickness, and the hinge 4a, made of plastic material, can be deformed so that the first outlet structure 4 can rotate relative to the second outlet structure 5 along the direction K.

[0129] In some embodiments, the battery cell 10 can comprise a lower plastic with an electrical insulating function. Both the first outlet structure 4 and the second outlet structure 5 belong to the lower plastic; that is, both the first outlet structure 4 and the second outlet structure 5 can serve as substructures of the lower plastic.

[0130] In some embodiments (not shown in the drawings), the first outlet structure and the second outlet structure can be provided separately, i.e., the first outlet structure is not connected to the second outlet structure. The first outlet structure may or may not be in contact with the second outlet structure, but the airflow channel of the first outlet structure remains connected to the airflow channel of the second outlet structure.

[0131] In some embodiments (not shown in the drawings), the battery cell may include a second outlet structure located between the top cover and the cell assembly. Two opposite ends of the airflow channel of the second outlet structure, running in the left-right direction, are each connected to the airflow channels of the corresponding first outlet structures.

[0132] In some embodiments, with reference to Fig. 22 and Fig. 23, the battery cell 10 may further comprise a third outlet structure 9, which is arranged between the housing bottom wall 12 of the housing 1a and the cell assembly 2. The airflow channel of the third outlet structure 9 may be connected to the airflow channel of the second outlet structure 5. In such an arrangement, the gas generated at the bottom of the cell assembly 2 may flow through the airflow channel of the third outlet structure 9 into the airflow channel of the second outlet structure 5, then the gas flows from the airflow channel of the second outlet structure 5 towards the explosion-proof valve 3, and the gas may be discharged through the explosion-proof valve 3 to the outside of the battery cell 10.

[0133] In some embodiments, the solution relating to “the airflow channel of the third outlet structure 9 is connected to the airflow channel of the second outlet structure 5” may include the following two connection solutions: In one connection solution, the airflow channel of the third outlet structure 9 is indirectly connected to the airflow channel of the second outlet structure 5 via other airflow channels, so that gas can flow from the airflow channel of the third outlet structure 9 into the airflow channel of the second outlet structure 5.In the other connection solution, the airflow channel of the third outlet structure 9 may not be directly connected to the airflow channel of the second outlet structure 5, or the airflow channel of the third outlet structure 9 may not be indirectly connected to the airflow channel of the second outlet structure 5 via other airflow channel structures, but the airflow channel of the third outlet structure 9 may be indirectly connected to the airflow channel of the second outlet structure 5 via a connecting space, so that the gas can flow from the airflow channel of the third outlet structure 9 into the airflow channel of the second outlet structure 5.

[0134] In some embodiments, with reference to Fig. 22, the battery cell 10 may further comprise an insulating film 8. The housing 1a and the cell assembly 2 are separated by the insulating film 8, and the third outlet structure 9 and the cell assembly 2 are separated by the insulating film 8. With reference to Fig. 23 The airflow channel of the third outlet structure 9 can include a third airflow channel 91. With reference to Fig. 24 The insulating film 8 can include a first vent opening 81, and the first vent opening 81 is connected to the third airflow channel 91. Referring to Fig. 25 A first outlet gap 8a can be provided between the insulating film 8 and the housing side wall 11, and the third airflow channel 91 can be connected to the airflow channel of the second outlet structure 5 via the first outlet gap 8a. In such an arrangement, the gas generated at the bottom of the cell assembly 2 can flow successively through the first vent opening 81, the third airflow channel 91, and the first outlet gap 8a into the airflow channel of the second outlet structure 5.

[0135] In some embodiments, with reference to Fig. 24, the first vent opening 81 can be located at the bottom of the insulating film 8, or the first vent opening 81 can be located on the section of the insulating film 8 that faces the bottom wall of the housing 12.

[0136] In some embodiments, with reference to Fig. 24, the insulating film 8 can be provided with a plurality of first vent openings 81.

[0137] In some embodiments, with reference to Fig. 24, the airflow channel of the second outlet structure 5 can comprise two third airflow channels 91 arranged opposite each other along the left-right direction, each third airflow channel 91 being connected to the first vent openings 81.

[0138] In some embodiments, with reference to Fig. 25, the housing side wall 11 can comprise the two first housing side walls 111 which are arranged opposite each other along the left-right direction and have a relatively small area, and a first outlet gap 8a can be provided between each first housing side wall 111 and the insulating film 8.

[0139] In some embodiments, with reference to Fig. 25, the first outlet gap 8a can extend along the top-bottom direction.

[0140] In some embodiments, with reference to Fig. 25, the third airflow channel 91, which is arranged on the left side, is connected via the first outlet gap 8a, which is arranged on the left side, to the second outlet structure 5, which is arranged on the left side, and the third airflow channel 91, which is arranged on the right side, is connected via the first outlet gap 8a, which is arranged on the right side, to the second outlet structure 5, which is arranged on the right side.

[0141] In some embodiments, with reference to Fig. 23, the airflow channel of the third outlet structure 9 can include a fourth airflow channel 92. With reference to Fig. 24. The insulating film 8 can include a second vent opening 82, and the second vent opening 82 is connected to the fourth airflow channel 92. With reference to Fig. 26 A second outlet gap 9a can be provided between the edge of the third outlet structure 9 and the housing side wall 11, and the fourth airflow channel 92 is connected to the first outlet gap 8a via the second outlet gap 9a. In such an arrangement, the gas generated at the bottom of the cell assembly 2 can flow successively through the second vent 82, the fourth airflow channel 92, the second outlet gap 9a, and the first outlet gap 8a into the airflow channel of the second outlet structure 5.

[0142] In some embodiments, with reference to Fig. 24, the second vent opening 82 can be located at the bottom of the insulating film 8, or the second vent opening 82 can be located on the section of the insulating film 8 that faces the bottom wall of the housing 12.

[0143] In some embodiments, with reference to Fig. 24, the insulating film 8 can be provided with a plurality of secondary vents 82.

[0144] In some embodiments, with reference to Fig. 26, the housing side wall 11 can comprise the two second housing side walls 112, which are arranged opposite each other along the front-back direction and have a relatively larger area, and a second outlet gap 9a can be provided between each second housing side wall 112 and the edge of the third outlet structure 9.

[0145] In some embodiments, such as in Fig. As shown in Figure 26, the second outlet gap 9a is located relatively close to the connecting section between the second housing side wall 112 and the housing bottom wall 12. The second outlet gap 9a can extend along the direction of expansion of the connecting section between the second housing side wall 112 and the housing bottom wall 12. That is, the second outlet gap 9a can extend along the left-right direction, so that the second outlet gap 9a extends to the bottom of the first outlet gap 8a and is connected to it.

[0146] In some embodiments, the airflow channel of the third outlet structure 9 can be connected to the airflow channel of the first outlet structure 4, so that the gas generated at the bottom of the cell assembly 2 can enter the airflow channel of the first outlet structure 4 through the airflow channel of the third outlet structure 9, whereupon the gas flows from the airflow channel of the first outlet structure 4 through the airflow channel of the second outlet structure 5 to the explosion-proof valve 3 and the gas is discharged outside the battery cell 10 through the explosion-proof valve 3.

[0147] In some embodiments, the solution relating to "the airflow channel of the third outlet structure 9 is connected to the airflow channel of the first outlet structure 4" may comprise the following three connection solutions: In one connection solution, the airflow channel of the third outlet structure 9 is directly connected to the airflow channel of the first outlet structure 4, so that gas can flow from the airflow channel of the third outlet structure 9 into the airflow channel of the first outlet structure 4. In another connection solution, the airflow channel of the third outlet structure 9 and the airflow channel of the first outlet structure 4 may be indirectly connected via other airflow channels, so that gas can flow from the airflow channel of the third outlet structure 9 into the airflow channel of the first outlet structure 4.In another connection solution, the airflow channel of the third outlet structure 9 can be connected neither directly nor indirectly to the airflow channel of the first outlet structure 4, but the airflow channel of the third outlet structure 9 can be connected indirectly to the airflow channel of the first outlet structure 4 via a connecting space, so that gas can flow from the airflow channel of the third outlet structure 9 into the airflow channel of the first outlet structure 4.

[0148] In some embodiments, with reference to Fig. 27, the base of the first outlet structure 4 can be provided with a third connecting opening 47. That is, an end of the first outlet structure 4 facing away from the second outlet structure 5 can be provided with a third connecting opening 47. That is, an end of the first outlet structure 4 that is close to the third outlet structure 9 can be provided with a third connecting opening 47. The third connecting opening 47 is connected to the first airflow channel 41 mentioned above, or the third connecting opening 47 is connected to the first groove 411 mentioned above. With reference to Fig. 28 The substructure of the insulating film 8, which is arranged below the base of the first outlet structure 4, can be provided with a fourth connecting opening 85. The airflow channel of the third outlet structure 9 is connected to the fourth connecting opening 85, or the third airflow channel 91 of the third outlet structure 9 is connected to the fourth connecting opening 85.The third connecting opening 47 can be connected to the fourth connecting opening 85, so that the gas in the airflow channel of the third outlet structure 9 can successively enter the airflow channel of the first outlet structure 4 through the fourth connecting opening 85 and the third connecting opening 47, then the gas flows from the airflow channel of the first outlet structure 4 into the airflow channel of the second outlet structure 5, then the gas flows in the airflow channel of the second outlet structure 5 towards the explosion-proof valve 3 and then the gas is released through the explosion-proof valve 3 to the outside of the battery cell 10.

[0149] In some embodiments, with reference to Fig. 23, the third outlet structure 9 can be a leaf-like structure. When viewed along the top-bottom direction, the ratio of the sum of the areas of the third airflow channel 91 and the area of ​​the fourth airflow channel 92 to the area of ​​the solid section of the third outlet structure 9 can be in a range from 0.1 to 1, for example, the value can be 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95 or 1.

[0150] In some embodiments, with reference to Fig. 24, the first vent 81 and the second vent 82 can both be hole structures.

[0151] In some embodiments, the ratio of the sum of the areas of the first vent opening 81 and the area of ​​the second vent opening 82 to the base area of ​​the cell assembly 2 can be in a range of 0.01 to 0.15, for example the value can be 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14 or 0.15.

[0152] In some other embodiments (not shown in the drawings), both the first and second vent openings can be outlet structures formed by tearing the insulating film. For example, the first vent opening can be torn and extended in the left-right direction, and the ratio of the tear length of the first vent opening to the length of the bottom of the cell assembly in the left-right direction can be in a range of 0.2 to 1, for example, the value can be 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1. For example, the second vent opening may be torn open and extended in the left-right direction, and the ratio of the torn length of the second vent opening to the length of the bottom of the cell assembly in the left-right direction may be in a range of 0.2 to 1, for example, the value may be 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 or 1.

[0153] In some embodiments, the maximum cross-sectional area of ​​the airflow channel of the first outlet structure 4 can be larger than the maximum cross-sectional area of ​​the airflow channel of the third outlet structure 9, and the maximum cross-sectional area of ​​the airflow channel of the second outlet structure 5 can be larger than the maximum cross-sectional area of ​​the airflow channel of the first outlet structure 4. In such an arrangement, the gas can be efficiently discharged to the outside through the explosion-proof valve.

[0154] In some embodiments, the housing 1a and the upper cover 1b may be welded together.

[0155] In some embodiments, the electrode pole 6 can extend through the upper cover 1b. The electrode pole 6 can be connected to the upper cover 1b via a component with an electrical insulating function (e.g., an upper plastic layer), so that the electrode pole 6 is insulated from the upper cover 1b. The electrode pole 6 can be connected to the upper cover 1b via a component with a sealing function, so that the electrode pole 6 is connected to the upper cover 1b in a sealed manner.

[0156] In some embodiments, the battery cell 10 can comprise two electrode poles 6. One of the electrode poles 6 can be a positive electrode, and the other electrode pole 6 can be a negative electrode.

[0157] In some embodiments, the cell assembly 2 can comprise a positive electrode foil, a negative electrode foil, a separator, and an electrolyte. A plurality of positive electrode foils and a plurality of negative electrode foils are stacked alternately, and the positive electrode foil and the negative electrode foil are separated from each other by the separator.

[0158] In some embodiments, the active material of the positive electrode foil of the cell assembly 2 can contain a lithium-containing metal oxide, such as lithium iron phosphate (LiFePO4), lithium cobalt oxide (LiCoO2), lithium manganate (LiMn2O4), lithium nickel oxide (LiNiO2) or lithium titanate (Li4Ti5O). 12 ) include.

[0159] In some embodiments, the active material of the positive electrode foil of cell assembly 2 may contain lead dioxide (PbO2).

[0160] In some embodiments, the active material of the negative electrode foil of the cell assembly 2 may comprise a carbon material, a silicon-based material, a tin-based material, or an alloy material.

[0161] In some embodiments, the separator of cell assembly 2 may contain polyethylene, polypropylene, or other polymeric materials. The separator may have a microporous structure, and this microporous structure may allow ions (such as lithium ions) to pass through.

[0162] In some embodiments, the electrolyte of cell assembly 2 is used to transport ions (such as lithium ions) between the positive electrode foil and the negative electrode foil, and the electrolyte may comprise a liquid electrolyte or a solid electrolyte.

[0163] In some embodiments, the explosion-proof valve 3 can have a predetermined breakable structure. If the internal pressure of the battery cell 10 is greater than the breakability threshold of the breakable structure, the breakable structure breaks and gas inside the battery cell 10 can escape to the outside of the battery cell.

[0164] The fragile structure can comprise a metal foil, such as aluminum foil or nickel foil. The metal sheet can be provided with a structural weakening line formed by etching, for example, a cross-shaped line, a U-shaped line, a C-shaped line, or annular line. When the metal sheet is exposed to relatively high atmospheric pressure within the battery cell 10, the stress concentration of the structural weakening line is relatively high, and the metal sheet can break.

[0165] In some embodiments, the explosion-proof valve 3 may include a resettable valve and a spring. When the internal pressure of the battery cell 10 is greater than the spring force, the resettable valve moves, and the gas inside the battery cell 10 can be released to the outside. When the internal pressure of the battery cell 10 is less than the spring force, the resettable valve is returned to its original position.

[0166] In a second aspect, the present disclosure provides some embodiments of the battery device. The battery device can comprise a plurality of battery cells that are electrically connected to one another. The battery cells can be embodiments of battery cell 10 according to the first aspect of the present disclosure described above. Therefore, the battery device can also achieve the effects of the embodiments of battery cell 10 according to the first aspect of the present disclosure described above, which are not repeated here.

[0167] In some embodiments, the battery cells in the battery device can be electrically connected in series, in parallel, or in a hybrid connection. The hybrid electrical connection can include both series and parallel connections.

[0168] In some embodiments, the battery device may further comprise a box body for receiving a plurality of electrically connected battery cells.

[0169] In some embodiments, the battery device may further include a battery management unit (BMU). The battery management unit can acquire information reflecting the operating state of the battery cell, such as the current, voltage, and temperature of the battery cell.

[0170] In a third aspect, some embodiments of the present disclosure provide an energy storage system, and the energy storage system can comprise a variety of battery devices. The battery devices can be embodiments of the battery device according to the second aspect of the present disclosure described above. Accordingly, the battery devices within the energy storage system are less prone to explosion.

[0171] In some embodiments, the energy storage system may further include a power conversion system (PCS). The battery device may be electrically connected to a power grid or electrical installation outside the energy storage system via the power conversion system. The power conversion system can convert alternating current (AC) to direct current (DC), and the battery device can store the electrical energy of the DC. The battery device can supply DC to the outside, and the power conversion system can convert the DC into the AC required by the power grid or the electrical installation.

[0172] In some embodiments, the energy storage system may further include a battery management system (BMS). The battery management system can acquire the operating status information of the battery devices and control the operation of the battery devices.

[0173] In a fourth aspect, the present disclosure provides some embodiments of electrical equipment. The electrical equipment may include a battery device, and the battery device may have embodiments of the battery device according to the second aspect of the present disclosure described above. Accordingly, the battery device within the electrical equipment is less prone to explosion.

[0174] In some embodiments, the electrical equipment may be a vehicle, an aircraft, a ship, a household electrical appliance, an industrial electrical appliance, or equipment that needs to consume electrical energy.

[0175] The above descriptions are only preferred embodiments of the present disclosure and are not intended to limit the present disclosure; various modifications and changes may be made by those skilled in the art. The scope of the present invention is defined by the appended claims.

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