Battery cells, battery packs and vehicles

Abstract

A battery cell (1), a battery pack (2), and a vehicle (4). The battery cell (1) is a housing (200), which has an internal cavity (110) and a first side wall (120) and a second side wall (130) opposed to each other, and the inner wall surface of the second side wall (130) is configured to have a recess (140) recessed in a direction opposite to the internal cavity (110), and the recess (140) forms an air discharge path (150) in the internal cavity (110), and the second side wall (1 The housing (30) includes a housing (200) having an explosion-proof hole (160) whose position corresponds to the air exhaust passage (150), a terminal (200) arranged on a side wall of the housing (100) other than the second side wall (130), an explosion-proof valve (300) installed on the second side wall (130) and used to cover the explosion-proof hole (160), and an electrode core body (400) arranged inside the housing (100) and separated from the explosion-proof hole (160).

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This disclosure claims priority to Chinese Patent Application No. 202221129270.9, filed by BYD Company Limited on May 12, 2022, entitled "BATTERY CELL, BATTERY PACK, AND VEHICLE."

[0002] The present disclosure relates to the technical field of vehicle technology, and more particularly to battery cells, battery packs, and vehicles. [Background technology]

[0003] In related art, the terminals and explosion-proof valves of a battery cell are generally located on the same side. When a battery cell experiences thermal runaway, the emitted high-temperature gas or flame can easily burn the terminals of the battery cell and the devices connected to it, causing high-voltage arc discharge or secondary damage.

[0004] Alternatively, the battery cell may be arranged with a boss that protrudes into the battery cell, and the explosion-proof valve may be arranged on the boss, with the explosion-proof valve spaced apart from the terminal. However, this arrangement of the boss reduces the internal space of the battery cell. Furthermore, the electrode core of the battery cell may directly contact the boss, blocking the explosion-proof hole, preventing the gas inside the battery from flowing normally to the outside, resulting in a low explosion-proof effect. Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure aims to solve at least one of the technical problems in the related art. To this end, an object of the present disclosure is to provide a battery cell, which has the advantages of high safety, large space, and smooth gas flow.

[0006] The present disclosure further provides a battery pack having a battery cell.

[0007] The present disclosure further provides a battery pack or battery packs having battery cells. [Means for solving the problem]

[0008] According to an embodiment of the first aspect of the present disclosure, a battery cell includes a housing having an internal cavity and a first side wall and a second side wall opposing each other, the second side wall having an internal wall surface configured with a recess that is recessed in a direction opposite to the internal cavity and forms a gas discharge path in the internal cavity, and the second side wall has an explosion-proof hole that positionally corresponds to the gas discharge path; a terminal disposed on a side wall of the housing other than the second side wall; an explosion-proof valve mounted on the second side wall and configured to cover the explosion-proof hole; and an electrode core disposed within the housing and spaced apart from the explosion-proof hole.

[0009] The battery cells according to the above embodiments of the present disclosure have the advantages of high safety, large space, and smooth gas flow.

[0010] According to some exemplary embodiments of the present disclosure, the recess has a first internal wall, a bottom wall, and a second internal wall connected in sequence. The first internal wall gradually extends in a direction away from the first side wall from an end remote from the bottom wall to an end connected to the bottom wall. The second internal wall gradually extends in a direction away from the first side wall from an end remote from the bottom wall to an end connected to the bottom wall. The extension direction of the bottom wall is the same as the extension direction of the second side wall.

[0011] According to some exemplary embodiments of the present disclosure, the outer wall surface of the second side wall is configured with a protrusion that protrudes in a direction opposite to the internal cavity, the protrusion corresponds to the recess, and the explosion-proof hole penetrates the protrusion and the recess.

[0012] According to some exemplary embodiments of the present disclosure, the thickness of the second sidewall at the protrusions and depressions is the same as its thickness at other locations.

[0013] According to some exemplary embodiments of the present disclosure, the protrusion and the recess are located at the center of the second side wall in the length direction of the second side wall.

[0014] According to some exemplary embodiments of the present disclosure, the protrusion has a first side surface, an upper surface, and a second side surface connected in order. The first side surface gradually extends in a direction away from the first side wall from an end remote from the upper surface to an end connected to the upper surface. The second side surface gradually extends in a direction away from the first side wall from an end remote from the upper surface to an end connected to the upper surface. The extension direction of the upper surface is the same as the extension direction of the second side wall.

[0015] According to some exemplary embodiments of the present disclosure, two opposing sides of the protrusion in the width direction of the second side wall are respectively at the same height as two opposing sides of the housing in the width direction of the second side wall.

[0016] According to some exemplary embodiments of the present disclosure, the explosion-proof valve is disposed in the protrusion or recess.

[0017] According to some exemplary embodiments of the present disclosure, the battery cell further includes a protective sheet connected to the housing and located on a side of the explosion-proof valve facing away from the internal cavity.

[0018] According to some exemplary embodiments of the present disclosure, the battery cell further includes an insulating film disposed within the internal cavity, the insulating film being located between at least a portion of the internal cavity and the explosion-proof valve.

[0019] According to some exemplary embodiments of the present disclosure, the dimension of the electrode core in the length direction of the recess is L1, the length of the recess is L2, and L1 and L2 satisfy 0.04≦L2 / L1≦0.96.

[0020] According to some exemplary embodiments of the present disclosure, L1 and L2 further satisfy L1≦500 mm and L2≧20 mm.

[0021] According to some exemplary embodiments of the present disclosure, the second side wall has a first support member and a second support member, each of which is located on two sides of the recess in the length direction of the second side wall. The electrode core is supported by the first support member and the second support member. The length of each of the first support member and the second support member is (L1-L2) / 2.

[0022] According to some exemplary embodiments of the present disclosure, the depth of the depression ranges from 0.5 mm to 3 mm.

[0023] According to some exemplary embodiments of the present disclosure, the explosion-proof hole is located at the center of the electrode core in the thickness direction and / or the explosion-proof hole is located at the center of the electrode core in the length direction of the second side wall.

[0024] According to some exemplary embodiments of the present disclosure, the terminals include a positive terminal and a negative terminal, the housing is an aluminum housing, the positive terminal is electrically connected to the housing, and the difference between the voltage of the positive terminal and the voltage of the housing is 0 V or more and 2.5 V or less.

[0025] According to some exemplary embodiments of the present disclosure, the terminals include a positive terminal and a negative terminal, the housing is a steel housing, the negative terminal is electrically connected to the housing, and the difference between the voltage of the housing and the voltage of the negative terminal is 0 V or more and 2.5 V or less.

[0026] According to some exemplary embodiments of the present disclosure, the housing includes a housing body having a second side wall and an internal cavity formed therein, the housing body having an opening facing the second side wall and communicating with the internal cavity, and a housing cover mounted to the housing body and covering the internal cavity, the first side wall formed in the housing cover, and the terminal connected to the housing cover.

[0027] According to an embodiment of the second aspect of the present disclosure, a battery pack includes a box and a battery cell according to an embodiment of the first aspect of the present disclosure, the battery cell being installed in the box and the explosion-proof valve facing a bottom wall of the box.

[0028] The battery pack according to the embodiment of the second aspect of the present disclosure has advantages of high safety, large space, and smooth gas flow by using the battery cells.

[0029] According to an embodiment of the third aspect of the present disclosure, a vehicle includes a battery cell according to an embodiment of the first aspect of the present disclosure or a battery pack according to an embodiment of the second aspect of the present disclosure, wherein the first side wall is located above the second side wall.

[0030] The vehicle according to the embodiment of the third aspect of the present disclosure has the advantages of high safety, large space, and smooth gas flow by using the battery cell or battery pack.

[0031] Additional aspects and advantages of the disclosure will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by practice of the disclosure.

[0032] The above and / or other additional aspects and advantages of the present disclosure will become apparent and understandable from the following description of the embodiments taken in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0033] [Figure 1]1 is a schematic structural diagram of a battery cell according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic structural diagram of a battery cell according to an embodiment of the present disclosure, viewed from another perspective. [Figure 3] FIG. 1 is a cross-sectional view of a battery cell according to an embodiment of the present disclosure. [Figure 4] FIG. 4 is a partially enlarged view of the circled portion A of FIG. 3. [Figure 5] FIG. 4 is a partially enlarged view of the circled portion B of FIG. 3. [Figure 6] FIG. 1 is a schematic diagram of a battery pack according to an embodiment of the present disclosure. [Figure 7] 1 is a schematic diagram of a vehicle according to an embodiment of the present disclosure. [Figure 8] FIG. 2 is a schematic diagram of a vehicle according to another embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0034]

[0013] Embodiments of the present disclosure are described in detail below, examples of which are illustrated in the drawings, and throughout the description, the same or similar elements or elements having the same or similar functions are designated by the same or similar reference numerals. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to illustrate the present disclosure only and should not be construed as limitations on the present disclosure.

[0035] In describing the present disclosure, terms such as "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "interior," "exterior," and the like, indicate orientation or positional relationships based on those shown in the drawings, and are provided merely to facilitate or simplify the description of the present disclosure, and should be understood as not necessarily meaning or suggesting that the devices or components shown are provided in, or constructed or operated in, the specified orientation. Thus, such terms should not be construed as limitations of the present disclosure.

[0036] It should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or suggesting the relative importance or quantity of the technical features being shown. Thus, a feature qualified by "first" or "second" may explicitly or implicitly include one or more of the features. Furthermore, in the description of this disclosure, unless otherwise indicated, "plurality" means two or more.

[0037] A battery cell 1 according to an embodiment of the present disclosure will be described below with reference to the accompanying drawings.

[0038] As shown in FIGS. 1 to 5, a battery cell 1 according to an embodiment of the present disclosure includes a housing 100, a terminal 200, an explosion-proof valve 300, and an electrode core 400.

[0039] The housing 100 has an internal cavity 110 and a first side wall 120 and a second side wall 130 that face each other. The inner wall surface of the second side wall 130 is configured with a recess 140 that is recessed in the opposite direction from the internal cavity 110. The recess 140 forms a gas discharge path 150 that communicates with the internal cavity 110, and the second side wall 130 is provided with an explosion-proof hole 160 that communicates with the gas discharge path 150. The terminal 200 is disposed on a side wall of the housing 100 other than the second side wall 130. The explosion-proof valve 300 is mounted on the second side wall 130 and is configured to cover the explosion-proof hole 160. The electrode core 400 is disposed within the housing 100 and is spaced apart from the explosion-proof hole 160.

[0040] The explosion-proof valve 300 has an explosion value. When the pressure in the internal cavity 110 of the battery cell 1 is less than the explosion value of the explosion-proof valve 300, the battery is in a normal operating state. When the pressure in the internal cavity 110 is equal to or greater than the explosion value of the explosion-proof valve 300, the explosion-proof valve 300 is opened to rapidly release gas, thereby rapidly reducing the pressure in the internal cavity 110 and preventing the battery cell 1 from exploding. At this time, the explosion-proof valve 300 plays a role in preventing explosion.

[0041] In some embodiments of the present disclosure, an insulating film 500 is further disposed to insulate the explosion-proof valve 300 from the electrolyte in the internal cavity 110. The insulating film 500 is disposed in the internal cavity 110, and the insulating film 500 is located between at least a portion of the internal cavity 110 and the explosion-proof valve 300. The insulating film 500 can insulate the explosion-proof valve 300 from the electrolyte in the internal cavity 110 to prevent corrosion of the explosion-proof valve 300 due to long-term immersion in the electrolyte, prevent battery leakage, prevent an increase or decrease in the opening pressure of the explosion-proof valve 300 due to the influence of the electrolyte, and enable the explosion-proof valve 300 to be in a stable and reliable operating state.

[0042] For example, the insulating film 500 may be made from polypropylene (PP), polyethylene (PE), or other polyester compounds.

[0043] In some embodiments of the present disclosure, the insulating film 500 is spaced from the walls of the gas exhaust path 150, and the insulating film 500 is gas impermeable. When the gas pressure in the portion of the internal cavity 110 other than the gas exhaust path 150 is low, the gas exhaust path 150 is not in communication with the portion of the internal cavity 110 other than the gas exhaust path 150. When the gas pressure in the internal cavity 110 increases, the insulating film is deformed under pressure, allowing the gas in the portion of the internal cavity 110 other than the gas exhaust path 150 to pass through the insulating film 500 and enter the gas exhaust path 150.

[0044] In some embodiments of the present disclosure, the insulating film 500 is spaced apart from the walls of the gas exhaust channel 150, and the insulating film 500 is gas impermeable. In this case, the gas exhaust channel 150 communicates with a portion of the internal cavity 110 other than the gas exhaust channel 150, and gas in the portion of the internal cavity 110 other than the gas exhaust channel 150 can pass through the insulating film 500 and enter the gas exhaust channel 150.

[0045] In some embodiments of the present disclosure, the insulating film 500 can be positioned so as to be directly attached to the wall of the gas exhaust channel 150. In this case, the gas exhaust channel 150 communicates with the portion of the internal cavity 110 other than the gas exhaust channel 150, and gas in the portion of the internal cavity 110 other than the gas exhaust channel 150 can directly enter the gas exhaust channel 150.

[0046] In a battery cell 1 according to an embodiment of the present disclosure, a housing 100 is configured with an internal cavity 110 and opposing first and second side walls 120 and 130. A terminal 200 is disposed on a side wall of the housing 100 other than the second side wall 130, which has an explosion-proof hole 160. An explosion-proof valve 300 is mounted on the second side wall 130 and configured to cover the explosion-proof hole 160. Because the terminal 200 and the explosion-proof hole 160 are disposed on different walls of the housing 100, the terminal 200 is separated from the explosion-proof hole 160. In the event of a thermal runaway of the battery cell 1, high-temperature gas or flames ejected from the explosion-proof hole 160 will not burn the terminal 200, preventing secondary damage and providing high safety performance. Furthermore, an electrode core 400 is disposed within the housing 100 and separated from the explosion-proof hole 160. Therefore, the electrode core 400 does not block the explosion-proof hole 160, and the gas in the gas discharge path 150 passes through the explosion-proof hole 160 and communicates with the outside.

[0047] Additionally, the inner wall surface of the second side wall 130 is configured with a recess 140, which is recessed in the opposite direction to the internal cavity 110. It should be understood that the internal cavity 110 can accommodate the electrode core 400. The recess 140 is formed by recessing a portion of the second side wall of the housing in the related art in a direction away from the first side wall, and the recess 140 does not reduce the space of the internal cavity 110. That is, the volume of the internal cavity 110 of the battery cell 1 in the embodiment of the present disclosure is the same as the volume of the internal cavity of a battery cell in the related art. The space within the internal cavity 110 is sufficiently large, allowing the volume of the electrode core 400 to be large, thereby ensuring the energy density of the battery cell 1.

[0048] In addition, the recess 140 forms a gas discharge path 150 that communicates with the internal cavity 110, and the explosion-proof hole 160 communicates with the gas discharge path 150. The portion of the second side wall 130 other than the recess 140 can be in contact with the electrode core body 400. As a result, the recess 140 is separated from the electrode core body 400, and the space between the recess 140 and the electrode core body 400 can form the gas discharge path 150.

[0049] Because the explosion-proof valve 300 is disposed on the second side wall 130 on a different side from the terminal 200, the space between the electrode core 400 and the second side wall 130 is small, and the gas generated by the electrode core 400 cannot be stored. If the recess 140 were not disposed, the gas generated by the electrode core 400 would move into the space between the electrode core 400 and the first side wall 120. When the pressure in the internal cavity 110 reaches the explosion value of the explosion-proof valve 300, the gas in the internal cavity 110 cannot be quickly discharged through the explosion-proof hole 160, causing a great danger.

[0050] In the present disclosure, the recess 140 is disposed to form a gas discharge path 150 for storing gas generated by the electrode core 400. When the pressure in the internal cavity 110 reaches the explosion value of the explosion-proof valve 300, the explosion-proof valve 300 is opened, and the gas discharge path 150 communicates with the outside through the explosion-proof hole 160. In this way, the gas inside the battery cell 1 can be quickly released through the explosion-proof hole 160, allowing the gas to flow smoothly and be discharged freely, resulting in a higher explosion-proof effect.

[0051] Therefore, the battery cell 1 according to the embodiment of the present disclosure has the advantages of high safety, large space, and smooth gas flow.

[0052] In some specific embodiments of the present disclosure, the terminal 200 is disposed on the first side wall 120, and the explosion-proof hole 160 is disposed on the second side wall 130. That is, the terminal 200 and the explosion-proof hole 160 are disposed on two opposite sides of the housing 100. Therefore, the terminal 200 and the explosion-proof hole 160 are sufficiently spaced apart, and the distance between the terminal 200 and the explosion-proof hole 160 is large. In the event of a thermal runaway of the battery cell 1, the high-temperature gas or flame emitted from the explosion-proof hole 160 will not burn the terminal 200, substantially preventing secondary damage and providing high safety performance. Furthermore, the electrode core 400 does not block the explosion-proof hole 160, and the gas in the first gas flow path 510 is in communication with the outside through the explosion-proof hole 160.

[0053] In some specific embodiments of the present disclosure, as shown in Figures 3 and 5, recess 140 has a first interior wall 141, a bottom wall 142, and a second interior wall 143 connected in sequence.

[0054] The first internal wall 141 gradually extends in a direction away from the first side wall 120 from its end away from the bottom wall 142 to its end connected to the bottom wall 142. That is, the distance between the first internal wall 141 and the first side wall 120 gradually increases in the direction from the end of the first internal wall 141 away from the bottom wall 142 to the end connected to the bottom wall 142. The second internal wall 143 gradually extends in a direction away from the first side wall 120 from its end away from the bottom wall 142 to its end connected to the bottom wall 142. That is, the distance between the second internal wall 143 and the first side wall 120 gradually increases in the direction from the end of the second internal wall 143 away from the bottom wall 142 to the end connected to the bottom wall 142. The extension direction of the bottom wall 142 is the same as the extension direction of the second side wall 130.

[0055] For example, in the direction from the first side wall 120 to the second side wall 130, the first internal wall 141 gradually slopes toward the second internal wall 143, and the second internal wall 143 gradually slopes toward the first internal wall 141. Therefore, the recess 140 is configured with a generally isosceles trapezoidal structure, which improves the structural strength of the second side wall 130. Furthermore, the first internal wall 141, the bottom wall 142, and the second internal wall 143 are arranged along the length direction of the second side wall 130.

[0056] Furthermore, the first internal wall 141 and the second internal wall 143 serve as connecting and transitional portions and serve to separate the bottom wall 142 from the electrode core 400, so that there is a gap between the bottom wall 142 and the electrode core 400, thereby forming a gas discharge path 150 that is connected to the internal cavity 110.

[0057] 1 to 5, the outer wall surface of the second side wall 130 is configured with a protrusion 170. The protrusion 170 protrudes in a direction opposite to the internal cavity 110, the protrusion 170 corresponds in position to the recess 140, and the explosion-proof hole 160 passes through the protrusion 170 and the recess 140.

[0058] That is, the protrusion 170 protrudes away from the internal cavity 110 corresponding to the portion of the recess 140 that is recessed away from the internal cavity 110. The thickness of the second side wall 130 at the recess 140 and the protrusion 170 may be greater, which improves the structural strength of the second side wall 130 and makes the overall structural strength of the housing 100 greater.

[0059] Furthermore, the explosion-proof hole 160 may penetrate the recess 140 and the protrusion 170 in a direction perpendicular to the second side wall 130, thereby connecting the internal cavity 110 of the battery cell 1 with the outside. The extension length of the explosion-proof hole 160 may be the same as the thickness of the second side wall 130. That is, the length of the explosion-proof hole 160 can be shorter, resulting in a much simpler structure.

[0060] In some specific embodiments of the present disclosure, as shown in Figure 3, the thickness of the second side wall 130 at the protrusions 170 and the recesses 140 is the same as its thickness at other locations. This ensures uniformity in the thickness of the second side wall 130, making the thickness of the second side wall 130 more uniform and preventing uneven local thicknesses of the second side wall 130, further improving the structural strength of the second side wall 130 and increasing the overall structural strength of the housing 100.

[0061] In some particular embodiments of the present disclosure, as shown in FIGS. 2 and 3, the protrusion 170 and the depression 140 are located at the center of the second side wall 130 in the length direction of the second side wall 130.

[0062] It can be understood that the electrode core 400 of the battery cell 1 generates gas. By locating the recess 140 at the center of the second side wall 130 in the longitudinal direction, the gas discharge path 150 can be located at the center of the electrode core 400 in the longitudinal direction. Gas generated by the electrode core 400 can easily enter the gas discharge path 150. Furthermore, the distances from the gas discharge path 150 to the two sides of the second side wall 130 in the longitudinal direction are the same, and the distances from gas generated by the two sides of the electrode core 400 in the longitudinal direction of the second side wall 130 to the gas discharge path 150 are the same. This eliminates the situation where gas on one side has difficulty entering the gas discharge path 150, making gas discharge in the battery cell 1 smoother.

[0063] In addition, such a configuration makes the structure of the housing 100 symmetrical in the length direction of the second side wall 130, and the housing 100 has the same structural strength in the length direction on both sides of the second side wall 130. This is beneficial in maintaining the uniformity of the structural strength of the housing 100.

[0064] In some particular embodiments of the present disclosure, as shown in FIGS. 3 and 5, the protrusion 170 has a first side surface 171, a top surface 172, and a second side surface 173 connected in sequence.

[0065] The first side surface 171 gradually extends in a direction away from the first side wall 120 from its end away from the top surface 172 to its end connected to the top surface 172. That is, the distance between the first side surface 171 and the first side wall 120 gradually increases in the direction from the end of the first side surface 171 away from the top surface 172 to its end connected to the top surface 172. The second side surface 173 gradually extends in a direction away from the first side wall 120 from its end away from the top surface 172 to its end connected to the top surface 172. That is, the distance between the second side surface 173 and the first side wall 120 gradually increases in the direction from the end of the second side surface 173 away from the top surface 172 to its end connected to the top surface 172. The extension direction of the top surface 172 is the same as the extension direction of the second side wall 130.

[0066] For example, in the direction from the first side wall 120 to the second side wall 130, the first side surface 171 gradually slopes toward the second side surface 173, and the second side surface 173 gradually slopes toward the first side surface 171. Therefore, the protrusion 170 has a generally isosceles trapezoidal structure, which improves the structural strength of the second side wall 130 and reduces the difficulty of processing. Furthermore, the first side surface 171, the top surface 172, and the second side surface 173 are arranged along the length direction of the second side wall 130.

[0067] Furthermore, in order to prevent the occurrence of uneven local thickness of the second side wall 130 and further improve the structural strength of the second side wall 130, the structure of the recess 140 is arranged to correspond to the structure of the protrusion 170, and the thickness of the second side wall 130 is kept constant.

[0068] In some specific embodiments of the present disclosure, as shown in FIG. 2, two opposing sides of the protrusion 170 in the width direction of the second side wall 130 are each at the same height as two opposing sides of the housing 100 in the width direction of the second side wall 130.

[0069] That is, the dimension of the protrusion 170 in the width direction of the second side wall 130 can be maximized, which increases the dimension of the recess 140 in the width direction of the second side wall 130. In this way, the gas discharge channel 150 has a large volume, can accommodate more gas, and provides better explosion-proof effect. Furthermore, while the volume of the gas discharge channel 150 remains unchanged, if the dimension of the gas discharge channel 150 in the width direction of the second side wall 130 is large, a small dimension can be set for the gas discharge channel 150 in the length direction of the second side wall 130, which improves the structural strength of the recess 140 and the protrusion 170, and therefore improves the structural strength of the second side wall 130.

[0070] Additionally, the protrusion 170 and the exterior structure of the housing 100 are flatter, making the overall structure of the housing 100 much simpler and easier to process, further improving the overall structural strength of the housing 100.

[0071] In some specific embodiments of the present disclosure, as shown in Figures 2, 3, and 5, the explosion-proof valve 300 is disposed in the protrusion 170 or the recess 140. The explosion-proof valve 300 can be welded to the protrusion 170 or the recess 140.

[0072] For example, the explosion-proof valve 300 can be disposed in the recess 140. In this way, the explosion-proof valve 300 can be disposed within the internal cavity 110 of the housing 100. As a result, the explosion-proof valve 300 does not protrude from the housing 100, and the housing 100 can protect the explosion-proof valve 300. Alternatively, the explosion-proof valve 300 can be disposed in the protrusion 170. That is, the explosion-proof valve 300 is disposed outside the housing 100. In this case, there is a larger assembly space outside the housing 100, making it easier to assemble the explosion-proof valve 300 to the housing 100.

[0073] In some specific embodiments of the present disclosure, the battery cell 1 further includes a protective sheet (not shown), which is connected to the housing 100 and is located on the side of the explosion-proof valve 300 facing away from the internal cavity 110.

[0074] The protective sheet can shield the explosion-proof valve 300. Whether the explosion-proof valve 300 is installed in the protrusion 170 or the recess 140, the protective sheet can prevent other parts of the vehicle from coming into direct contact with the explosion-proof valve 300. In addition, the protective sheet also protects the explosion-proof valve 300 during transportation of the battery cell 1, preventing damage to the explosion-proof valve 300 due to impact during transportation and extending the life of the battery cell 1.

[0075] In some specific embodiments of the present disclosure, the depth D of the depression 140 ranges from 0.5 mm to 3 mm, as shown in Figure 4. For example, the depth of the depression 140 can be 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, or 3 mm.

[0076] Therefore, the recess 140 can be configured to have a large depth, so that the gas discharge path 150 has a large space and can accommodate more gas, allowing the gas generated by the electrode core 400 to be discharged quickly for explosion protection. Therefore, the gas flows more smoothly, and the explosion prevention effect is better. Furthermore, to prevent a large loss of capacity in the electrode core 400 and allow the battery cell 1 to have a small volume while ensuring a high energy density, the depth of the recess 140 should not be too large, and therefore the space occupied by the recess 140 in the battery cell 1 is not too large.

[0077] 3, the dimension of the electrode core 400 in the length direction of the recess 140 is L1, the length of the recess 140 is L2, and L1 and L2 satisfy 0.04≦L2 / L1≦0.96. For example, L2 / L1 can be 0.04, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 0.96.

[0078] In this way, the recess 140 is prevented from having an excessively small dimension in the longitudinal direction of the electrode core 400, so the gas discharge path 150 can have a large dimension in the longitudinal direction of the electrode core 400, and the gas discharge path 150 can have a large space, allowing gas to be discharged freely. Also, since the recess 140 is prevented from having an excessively large dimension in the longitudinal direction of the electrode core 400, the portions of the second side wall 130 other than the recess 140 can have large dimensions. These portions can stably support the electrode core 400, prevent the electrode core 400 from contacting the bottom wall 142 of the recess 140, and ensure the flow of gas in the gas discharge path.

[0079] Furthermore, the dimension L1 of the electrode core 400 in the longitudinal direction of the recess 140 is 500 mm or less, and the length L2 of the recess 140 is greater than 20 mm.

[0080] Therefore, the length of the electrode core 400 is not too large, so the overall length of the battery cell 1 is not too large, thereby improving the overall structural strength of the battery cell 1. In addition, the length of the recess 140 is not too short. Therefore, the length of the gas discharge path 150 is kept sufficiently long, so that the gas discharge path 150 has a large space and allows gas to be discharged more smoothly.

[0081] 3, the second side wall 130 has a first support member 131 and a second support member 132. The first support member 131 and the second support member 132 are respectively located on two sides of the recess 140 in the length direction of the second side wall 130. The electrode core 400 is supported by the first support member 131 and the second support member 132. The length of each of the first support member 131 and the second support member 132 is (L1-L2) / 2.

[0082] In this way, the gas discharge path 150 can be positioned at the center of the second side wall 130 in the longitudinal direction. Gas generated by the electrode core 400 can more easily enter the gas discharge path 150, and the gas can be more smoothly discharged from the battery cell 1. Furthermore, the first support member 131 and the second support member 132 have the same length, and the structural strength of the first support member 131 is the same as the structural strength of the second support member 132. That is, the second side wall 130 has matching structural strength on both sides in the longitudinal direction, which allows the first support member 131 and the second support member 132 to support the electrode core 400 more stably and reliably.

[0083] In some specific embodiments of the present disclosure, as shown in Figures 2 and 3, the explosion-proof hole 160 is located at the center of the electrode core 400 in the thickness direction and / or the explosion-proof hole 160 is located at the center of the electrode core 400 in the length direction of the second side wall 130.

[0084] For example, the explosion-proof hole 160 can be located at the center of the electrode core 400 in the thickness direction and at the center of the electrode core 400 in the length direction of the second side wall 130. Generally, most gas is generated at the center of the electrode core 400. By locating the explosion-proof hole 160 at the center of the electrode core 400, the explosion-proof valve 300 can more effectively sense the gas pressure in the battery cell 1. When the gas pressure in the battery cell 1 is too high, the explosion-proof valve 300 can be immediately opened to release the gas inside the battery cell 1, thereby further improving the explosion-proof effect of the battery cell 1.

[0085] 1 and 3, the terminal 200 includes a positive terminal 210 and a negative terminal 220. The housing 100 is an aluminum housing. In this case, the explosion-proof valve 300 is made of aluminum, the positive terminal 210 is electrically connected to the housing 100, and the difference between the voltage of the positive terminal 210 and the voltage of the housing 100 ranges from 0 V to 2.5 V. The difference between the voltage of the positive terminal 210 and the voltage of the housing 100 refers to the value obtained by subtracting the voltage of the housing 100 from the voltage of the positive terminal 210.

[0086] It should be understood that the housing 100 and the anti-explosion valve 300 may be made of metallic aluminum or an aluminum alloy, and the electrolyte in the battery cell 1 is usually a lithium-ion electrolyte. Aluminum reacts with lithium ions at low potential to form a metal compound. Therefore, when the voltage difference between the positive terminal 210 and the housing 100 is small, the voltage of the housing 100 approaches the voltage of the positive terminal 210, i.e., the potential of the housing 100 is raised. This prevents the housing 100 and the anti-explosion valve 300 from being corroded by the lithium-ion electrolyte, protecting the housing 100 and the anti-explosion valve 300 installed in the housing 100, and therefore extending the life of the battery cell 1.

[0087] Furthermore, a resistor is connected between the positive terminal 210 and the housing 100. Therefore, even if the positive terminal 210 of the battery cell 1 and the housing 100 form a loop, for example, when the positive terminal 210 of the battery cell 1 is connected to the negative terminal of the battery without a resistor and the housing 100 is connected to the positive terminal of the battery, the resistor between the positive terminal 210 of the battery cell 1 and the housing 100 can protect the battery cell 1 and prevent the battery cell 1 from being short-circuited, allowing the battery cell 1 to have high safety performance during use.

[0088] In some specific embodiments of the present disclosure, as shown in Figures 1 and 3, terminal 200 includes positive terminal 210 and negative terminal 220. Housing 100 is a steel housing. In this case, explosion-proof valve 300 may be made of steel. Negative terminal 220 is electrically connected to housing 100, and the difference between the voltage of housing 100 and the voltage of negative terminal 220 ranges from 0 V to 2.5 V. The difference between the voltage of housing 100 and the voltage of negative terminal 220 refers to a value obtained by subtracting the voltage of negative terminal 220 from the voltage of housing 100.

[0089] It should be understood that steel reacts with lithium ions at a high potential to form a metallic compound. When the voltage difference between the negative terminal 220 and the housing 100 is small, the voltage of the housing 100 approaches the voltage of the negative terminal 220, i.e., the potential of the housing 100 is lowered. This prevents the housing 100 and the explosion-proof valve 300 from being corroded by the lithium ion electrolyte, protecting the housing 100 and the explosion-proof valve 300 installed in the housing 100, and thus further preventing the housing 100 and the explosion-proof valve 300 from being corroded, thereby extending the life of the battery cell 1.

[0090] Furthermore, a resistor is connected between the negative terminal 220 and the housing 100. Therefore, even if the negative terminal 220 of the battery cell 1 and the housing 100 form a loop, for example, when the negative terminal 220 of the battery cell 1 is connected to the positive terminal of the battery without a resistor and the housing 100 is connected to the negative terminal of the battery, the resistor between the negative terminal 220 of the battery cell 1 and the housing 100 can protect the battery cell 1 and prevent the battery cell 1 from being short-circuited, allowing the battery cell 1 to have high safety performance during use.

[0091] In some specific embodiments of the present disclosure, as shown in FIGS. 1-3, the housing 100 includes a housing body 180 and a housing cover 190.

[0092] The second sidewall 130 and the internal cavity 110 are formed in the housing body 180, and the housing body 180 has an opening facing the second sidewall 130, the opening communicating with the internal cavity 110. A housing cover 190 is attached to the housing body 180, and the housing cover 190 covers the internal cavity 110. The first sidewall 120 is formed in the housing cover 190, and the terminal 200 is connected to the housing cover 190. By configuring the housing 100 to include separate components, the difficulty of processing the housing 100 is reduced, simplifying the processing steps of the housing body 180 and the housing cover 190 and making processing more convenient, and it is also convenient to place the electrode core 400 and the electrolyte in the internal cavity 110.

[0093] 6 , a battery pack 2 according to an embodiment of the second aspect of the present disclosure includes a box 3 and a battery cell 1 according to an embodiment of the first aspect of the present disclosure. The battery cell 1 is installed in the box 3, and the anti-explosion valve 300 faces the bottom wall of the box 3. Therefore, in the event of thermal runaway of the battery cell 1, high-temperature gas or flame can be ejected to the bottom of the box 3 through the anti-explosion valve 300.

[0094] The battery pack according to the embodiment of the present disclosure has the advantages of high safety, smooth gas flow, and high explosion-proof effect by using the battery cell 1.

[0095] 7 and 8 , a vehicle 4 according to an embodiment of the third aspect of the present disclosure includes a battery cell 1 according to an embodiment of the first aspect of the present disclosure or a battery pack 2 according to an embodiment of the second aspect of the present disclosure. The battery pack 2 is mounted to the vehicle body of the vehicle 4 or the chassis of the vehicle 4 by a box 3. Alternatively, the vehicle 4 includes the battery cell 1 according to the embodiment of the first aspect of the present disclosure, and the battery cell 1 is mounted to the vehicle body of the vehicle 4 or the chassis of the vehicle 4. That is, the battery cell 1 may be directly mounted to the vehicle body of the vehicle 4 or the chassis of the vehicle 4. Alternatively, the battery cell 1 is mounted in a box 3 and assembled into the battery pack 2, and the battery pack 2 is mounted to the vehicle body of the vehicle 4 or the chassis of the vehicle 4 by the box 3.

[0096] By using the battery cells 1 or the battery pack 2, the vehicle 4 according to the embodiment of the present disclosure has the advantages of high safety, large space, and smooth gas flow.

[0097] In some particular embodiments of the present disclosure, the battery cell 1 or battery pack 2 is mounted to the vehicle body or chassis of the vehicle 4, and the first side wall 120 is positioned above the second side wall 130.

[0098] Therefore, the first side wall 120 may face the interior of the vehicle 4, and the second side wall 130 may face the exterior of the vehicle 4. That is, the explosion-proof valve 300 may face away from the passenger compartment of the vehicle 4. When the battery cell 1 experiences thermal runaway, hot gas or flames can be ejected through the explosion-proof valve 300 in the direction away from the passenger compartment of the vehicle 4, thus reducing the possibility of injury to passengers in the vehicle and protecting the safety of passengers in the vehicle.

[0099] Other configurations and operations of the battery cell 1, the battery pack 2, and the vehicle 4 according to embodiments of the present disclosure are known to those skilled in the art and will not be described in detail here.

[0100] In the description herein, a description that refers to terms such as "an embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples" means that the specific feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. As used herein, exemplary descriptions of the above terms do not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments.

[0101] While embodiments of the present disclosure have been shown and described, it should be understood by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principle and scope of the present disclosure, the scope of which is defined by the appended claims and their equivalents. [Explanation of symbols]

[0102] 1 battery cell 2 battery packs 3 boxes 4 vehicles 100 Housing 110 Internal cavity 120 First side wall 130 Second Side Wall 131 first support member 132 second support member 140 hollow 141 First Interior Wall 142 Bottom wall 143 Second Inner Wall 150 Gas exhaust channel 160 Explosion proof hole 170 Protrusion, protrusion 171 First Aspect 172 Top surface 173 Second Aspect 180 Housing body 190 Housing cover 200 terminals 210 Positive terminal 220 Negative terminal 300 Explosion-proof valve 400 Electrode core 500 insulating film

Claims

1. A battery cell (1), A housing (100) having an internal cavity (110) and a first side wall (120) and a second side wall (130) opposed to each other, the internal wall surface of the second side wall (130) being configured with a depression (140), the depression (140) being depressed in a direction opposite to the internal cavity (110), the depression (140) forming an air discharge passage (150) in the internal cavity (110), and an explosion-proof hole (160) being provided in the second side wall (130) positionally corresponding to the air discharge passage (150); a terminal (200) disposed on a side wall of the housing (100) other than the second side wall (130); an explosion-proof valve (300), the explosion-proof valve (300) being mounted to the second side wall (130), the explosion-proof valve (300) being configured to cover the explosion-proof hole (160); an electrode core (400), the electrode core (400) being disposed in the housing (100), the electrode core (400) being spaced apart from the explosion-proof hole (160); Equipped with The battery cell (1), wherein the outer wall surface of the second side wall (130) has a protrusion (170), the protrusion (170) protrudes in a direction opposite to the internal cavity (110), the protrusion (170) positionally corresponds to the recess (140), and the explosion-proof hole (160) passes through the protrusion (170) and the recess (140).

2. 2. The battery cell of claim 1, wherein the recess has a first internal wall, a bottom wall, and a second internal wall connected in order, the first internal wall extending in a direction away from the first side wall from an end remote from the bottom wall to an end connected to the bottom wall, and the second internal wall extending in a direction away from the first side wall from an end remote from the bottom wall to an end connected to the bottom wall, the extension direction of the bottom wall being the same as the extension direction of the second side wall.

3. The battery cell (1) according to claim 1, wherein the thickness of the second side wall (130) at the protrusion (170) and the recess (140) is the same as the thickness at other positions.

4. The battery cell (1) according to claim 1, wherein the protrusion (170) and the recess (140) are located at the center of the second side wall (130) in the length direction of the second side wall (130).

5. 5. The battery cell (1) according to claim 1, wherein the protrusion (170) has a first side surface (171), a top surface (172), and a second side surface (173) connected in order, the first side surface (171) extending in a direction away from the first side wall (120) from an end remote from the top surface (172) to an end connected to the top surface (172), the second side surface (173) extending in a direction away from the first side wall (120) from an end remote from the top surface (172) to an end connected to the top surface (172), and the extension direction of the top surface (172) is the same as the extension direction of the second side wall (130).

6. 5. A battery cell (1) according to claim 1, wherein two opposing sides of the protrusion (170) in the width direction of the second side wall (130) are each at the same height as two opposing sides of the housing (100) in the width direction of the second side wall (130).

7. The battery cell (1) according to any one of claims 1 to 4, wherein the explosion-proof valve (300) is disposed in the protrusion (170) or the recess (140).

8. 5. The battery cell (1) according to claim 1, further comprising a protective sheet, the protective sheet being connected to the housing (100), and the protective sheet being located on a side of the explosion-proof valve (300) facing away from the internal cavity (110).

9. 5. The battery cell (1) according to claim 1, further comprising an insulating film (500), the insulating film (500) being disposed in the internal cavity (110), and the insulating film (500) being positioned between at least a portion of the internal cavity (110) and the explosion-proof valve (300).

10. The dimension of the electrode core (400) in the longitudinal direction of the recess (140) is L １ and the length of the recess (140) is L ２ and L １ and L ２ The battery cell (1) according to any one of claims 1 to 4, wherein L2 / L1 satisfies 0.04≦L2 / L1≦0.

96.

11. L １ and L ２ But further, L １ ≦500 mm and L ２ 11. The battery cell (1) according to claim 10, wherein the thickness satisfies ≧20 mm.

12. The second side wall (130) has a first support member (131) and a second support member (132), the first support member (131) and the second support member (132) are respectively located on two sides of the recess (140) in the length direction of the second side wall (130), the electrode core (400) is supported by the first support member (131) and the second support member (132), and the length of each of the first support member (131) and the second support member (132) is (L １ -L ２ ) / 2.

13. 5. The battery cell (1) according to any one of claims 1 to 4, wherein the depth of the recess (140) is in the range of 0.5 mm to 3 mm.

14. The explosion-proof hole (160) is located at the center of the electrode core (400) in the thickness direction, and / or The battery cell (1) according to any one of claims 1 to 4, wherein the explosion-proof hole (160) is located at the center of the electrode core (400) in the longitudinal direction of the second side wall (130).

15. 5. The battery cell according to claim 1, wherein the terminal comprises a positive terminal and a negative terminal, the housing is an aluminum housing, the positive terminal is electrically connected to the housing, and a difference between a voltage of the positive terminal and a voltage of the housing is 0 V or more and 2.5 V or less.

16. 5. The battery cell according to claim 1, wherein the terminals include a positive terminal and a negative terminal, the housing is a steel housing, the negative terminal is electrically connected to the housing, and a voltage difference between the housing and the negative terminal is between 0 V and 2.5 V.

17. The housing (100) a housing body (180) in which the second side wall (130) and the internal cavity (110) are formed, the housing body (180) being provided with an opening facing the second side wall (130), the opening communicating with the internal cavity (110); a housing cover (190), the housing cover (190) being mounted on the housing body (180), the housing cover (190) covering the internal cavity (110), the first side wall (120) being formed on the housing cover (190), and the terminals (200) being connected to the housing cover (190); The battery cell (1) according to any one of claims 1 to 4, comprising:

18. Box (3) and and the battery cell (1) according to claim 1, wherein the battery cell (1) is installed in the box (3), and the explosion-proof valve (300) faces the bottom wall of the box (3). Battery pack (2).

19. A battery pack (2) comprising the battery cell (1) according to any one of claims 1 to 4 or claim 18, wherein the first side wall (120) is located above the second side wall (130). Vehicle (4).

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