Batteries, battery modules, battery packs, and vehicles

Abstract

A vehicle having a battery pack. The battery pack includes a battery or a battery module. The battery includes a battery shell and an explosion-proof valve. The explosion-proof valve is disposed in the battery shell. The volume of the battery is V, and V is expressed in mm. 3 The explosion-proof valve is provided with a notch groove, and the explosion-proof valve has an opening area. In the depth direction of the notch groove, the outer edge of the orthogonal projection of the opening area is the predetermined opening boundary, and the orthogonal projection area of ​​the opening area is S, where S is in mm 2 S and V are 0.3 mm -1 ≦(5000×S) / V≦6mm -1 Meet the following.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This disclosure claims priority to Chinese Patent Application No. 202210512534.7, "Battery, battery module, battery pack and vehicle," filed on May 12, 2022 by BYD Co., Ltd., which is incorporated herein by reference in its entirety.

[0002] The present disclosure relates to the technical field of batteries, and in particular to batteries, battery modules, battery packs, and vehicles. [Background technology]

[0003] In the related art, the explosion-proof valve of a battery (such as a lithium-ion battery) is designed so that when the battery is used improperly and the gas pressure inside the battery increases, the explosion-proof valve can be opened in a timely manner to release the pressure, thereby protecting the battery from fire, explosion, and other safety problems. However, in actual use, there are problems such as fire, explosion, and other safety accidents caused by the battery's untimely or insufficient pressure release speed. Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure aims to solve at least one of the technical problems in the related art. To this end, it is an object of the present disclosure to provide a battery with improved safety during use.

[0005] Another object of the present disclosure is to provide a battery module containing a battery.

[0006] Another object of the present disclosure is to provide a battery pack including a battery or a battery module.

[0007] Another object of the present disclosure is to provide a vehicle including a battery or battery pack. [Means for solving the problem]

[0008] A battery according to an embodiment of the first aspect of the present disclosure includes a battery shell and an explosion-proof valve. The explosion-proof valve is disposed in the battery shell. The battery is 3 The explosion-proof valve has a volume V in units of mm. The explosion-proof valve is provided with a scored groove, and the explosion-proof valve has an opening area. In the depth direction of the scored groove, the outer edge of the orthogonal projection of the opening area is a predetermined opening boundary, and the orthogonal projection of the opening area has an area of ​​mm 2 The unit is S, and S and V are 0.3 mm. -1 Satisfy ≦(5000×S) / V.

[0009] According to the explosion-proof valve according to the embodiment of the present disclosure, by controlling the ratio of the area S of the opening region to the volume V of the battery, the pressure relief rate of the battery can be effectively improved, and the pressure inside the battery can be timely and quickly released, thus improving the protection of the battery. Moreover, the explosion-proof valve has high structural strength, which can ensure the safe use of the battery.

[0010] According to some example embodiments of the present disclosure, S and V are (5000×S) / V≦6 mm -1 Meet the following.

[0011] According to some example embodiments of the present disclosure, when the battery positive electrode material is a compound having an olivine structure, S and V are within 0.3 mm -1 ≦5000×S / V≦5mm -1 If the battery positive electrode material contains a layered compound, S and V are 0.5 mm -1 ≦5000×S / V≦6mm -1 Further satisfy.

[0012] According to some example embodiments of the present disclosure, S is 80 mm 2 ≦S≦1600mm 2 Meet the following.

[0013] According to some example embodiments of the present disclosure, V is 40000 mm 3 ≦V≦3500000mm 3 Meet the following.

[0014] According to some example embodiments of the present disclosure, the notch groove includes two oppositely arranged first circular arc segments, a first straight line segment, and two spaced apart second straight line segments. The first straight line segment is arranged parallel to the second straight line segment, and two ends of the first straight line segment are respectively connected to the two first circular arc segments, and each second straight line segment is connected to a corresponding first circular arc segment. In the depth direction of the notch groove, two free ends of an outer edge of an orthogonal projection of the notch groove are connected to form a connecting line, and the connecting line and the outer edge of the orthogonal projection of the notch groove together form a predetermined opening boundary.

[0015] According to some exemplary embodiments of the present disclosure, a first reinforcing groove is disposed in the opening region. The first reinforcing groove includes two fourth arc segments. The two fourth arc segments are symmetrically disposed along the width direction of the explosion-proof valve, and the vertices of the two fourth arc segments coincide. Two ends of one fourth arc segment extend to the second straight line segment, and two ends of the other fourth arc segment extend to the first straight line segment, respectively.

[0016] According to some example embodiments of the present disclosure, in a depth direction of the score groove, the depth of the first reinforcing groove is less than the depth of the score groove.

[0017] According to some example embodiments of the present disclosure, the score groove includes two oppositely disposed second arc segments and two parallelly disposed third straight line segments. Two ends of each third straight line segment are connected to two second arc segments respectively, and the two third straight line segments and the two second arc segments form a closed loop structure. In the depth direction of the score groove, an outer edge of the orthogonal projection of the score groove forms a predetermined opening boundary.

[0018] According to some example embodiments of the present disclosure, a second reinforcing groove is disposed in the opening region. The second reinforcing groove includes two eighth straight segments and one ninth straight segment. One end of each of the two eighth straight segments is connected to the ninth straight segment, an included angle is formed between the two eighth straight segments, the other ends of the two eighth straight segments extend to two third straight segments, respectively, and the other end of the ninth straight segment is connected to the second arc segment.

[0019] According to some example embodiments of the present disclosure, the score groove includes a fourth straight segment and four fifth straight segments. Two ends of the fourth straight segment are respectively connected to two fifth straight segments arranged at a preset included angle. In the depth direction of the score groove, an arc-shaped segment is defined between free ends of orthogonal projections of the two fifth straight segments arranged at the same end of the fourth straight segment. The arc-shaped segment has a vertex of the preset included angle as the center of a circle. A sixth straight segment is defined between free ends of orthogonal projections of the two fifth straight segments arranged at the same side of the fourth straight segment. The two arc-shaped segments and the two sixth straight segments together form a predetermined opening boundary.

[0020] According to some example embodiments of the present disclosure, an explosion-proof valve includes a connection segment, a support segment, and a buffer segment. The connection segment is connected to an outer periphery of the support segment, and the support segment and the connection segment are spaced apart along a thickness direction of the support segment. The buffer segment is connected between the connection segment and the support segment, and an opening region is disposed in the support segment.

[0021] According to some example embodiments of the present disclosure, a recess is formed in the explosion-proof valve, and a notched groove is formed in the bottom wall of the recess.

[0022] According to some example embodiments of the present disclosure, in the depth direction of the score groove, an outer edge of an orthogonal projection of the recess has an area superimposed with an outer edge of an orthogonal projection of the score groove.

[0023] According to some example embodiments of the present disclosure, the explosion-proof valve has an oval or racetrack shape.

[0024] According to some example embodiments of the present disclosure, the explosion-proof valve has a plate-like structure.

[0025] According to some example embodiments of the present disclosure, the energy density of the battery is ED, where ED satisfies 200wh / kg≦ED≦280wh / kg.

[0026] A battery module according to an embodiment of the second aspect of the present disclosure includes a battery according to an embodiment of the first aspect of the present disclosure.

[0027] A battery pack according to an embodiment of the third aspect of the present disclosure includes a battery according to an embodiment of the first aspect of the present disclosure or a battery module according to an embodiment of the second aspect of the present disclosure.

[0028] A vehicle according to an embodiment of the fourth aspect of the present disclosure includes a battery according to an embodiment of the first aspect, or includes a battery pack according to an embodiment of the third aspect of the present disclosure.

[0029] Additional aspects and advantages of the disclosure will be set forth in part in the description which follows, and in part will be apparent from the description, or may be learned by practice of the disclosure.

[0030] The foregoing and / or other additional aspects and advantages of the present disclosure will become apparent and understandable from the following description of the embodiments in conjunction with the accompanying drawings. [Brief description of the drawings]

[0031] [Figure 1] FIG. 1 is a schematic diagram illustrating a battery according to an embodiment of the present disclosure. [Diagram 2] 1 is a schematic cross-sectional view of an explosion-proof valve according to an embodiment of the present disclosure. [Diagram 3] FIG. 1 is a schematic diagram illustrating an explosion-proof valve according to an embodiment of the present disclosure. [Figure 4] FIG. 2 is a schematic diagram illustrating an explosion-proof valve according to another embodiment of the present disclosure. [Diagram 5] FIG. 2 is a schematic diagram illustrating an explosion-proof valve according to another embodiment of the present disclosure. [Figure 6] FIG. 2 is a schematic diagram illustrating an explosion-proof valve according to another embodiment of the present disclosure. [Figure 7] FIG. 2 is a diagram for roughly comparing the pressure release speed of the batteries in Comparative Example 1 and Examples 1 to 3 according to the present disclosure. [Figure 8] FIG. 1 is a diagram for roughly comparing the pressure release speed of the batteries in Comparative Example 1 and Examples 4 to 6 according to the present disclosure. [Figure 9] FIG. 13 is a diagram for roughly comparing the pressure release speed of the batteries in Comparative Example 2 and Examples 7 to 9 according to the present disclosure. [Figure 10] FIG. 13 is a diagram for roughly comparing the pressure release speed of the batteries in Comparative Example 2 and Examples 10 to 12 according to the present disclosure. [Figure 11] 1 is a schematic diagram of an explosion-proof valve having a plate-like structure according to an embodiment of the present disclosure. FIG. [Figure 12]1 is a schematic cross-sectional view of an explosion-proof valve having a plate-like structure according to an embodiment of the present disclosure. FIG. [Figure 13] 1 is a schematic diagram of a vehicle according to the present disclosure. [Figure 14] FIG. 2 is a schematic diagram illustrating a vehicle according to another embodiment of the present disclosure. [Figure 15] FIG. 2 is a schematic diagram illustrating a vehicle according to another embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] DETAILED DESCRIPTION OF THE DRAWINGS The embodiments of the present disclosure are described in detail below, and the embodiments described with reference to the accompanying drawings are exemplary. In the following, a battery 100 according to an embodiment of the first aspect of the present disclosure is described with reference to FIGS.

[0033] As shown in FIGS. 1-12, a battery 100 according to an embodiment of the first aspect of the present disclosure includes a battery shell 10 and an explosion-proof valve 20.

[0034] In particular, the battery 100 has a volume of V, where V is mm 3 The explosion-proof valve 20 is provided with a notched groove 25, and the explosion-proof valve 20 has an opening area 24. In the depth direction of the notched groove 25 (i.e., in the direction from the groove top to the groove bottom of the notched groove 25), the outer edge of the orthogonal projection of the opening area 24 is the predetermined opening boundary. The orthogonal projection of the opening area 24 has an area S, where S is in mm 2 The units are S and V: 0.3 mm -1≦(5000×S) / V. In the above formula, the area S of the orthogonal projection of the opening area 24 is expressed in square millimeters, and the volume V of the battery 100 is expressed in cubic millimeters. When the pressure inside the battery 100 is too high, the gas inside the battery 100 can be smoothly released from the opening area 24 of the explosion-proof valve 20, so as to ensure the safe use of the battery 100. Therefore, by controlling the ratio of the area S of the orthogonal projection of the opening area 24 to the volume V of the battery 100 to be within a suitable range, the pressure release speed of the battery 100 can be effectively improved, and the pressure inside the battery 100 can be timely and quickly released from the opening area 24 of the explosion-proof valve 20, thus improving the protection of the battery 100, and the explosion-proof valve 20 has a high structural strength that can ensure the safe use of the battery 100.

[0035] According to the battery 100 according to the embodiment of the present disclosure, by controlling the ratio of the area S of the orthogonal projection of the opening area 24 to the volume V of the battery 100, the pressure release speed of the battery 100 can be effectively improved, and the pressure inside the battery 100 can be timely and quickly released, thus improving the protection of the battery 100. In addition, the explosion-proof valve 20 has high structural strength, which can ensure the safe use of the battery 100.

[0036] According to some example embodiments of the present disclosure, S and V are 5000×S / V≦6 mm -1 Therefore, by controlling the ratio of the area S of the orthogonal projection of the opening area 24 to the volume V of the battery 100 to be within a suitable range, the pressure release speed of the battery 100 can be effectively improved, and the internal pressure of the battery 100 can be timely and quickly released, thus improving the protection of the battery 100, and the explosion-proof valve 20 has high structural strength to ensure the safe use of the battery 100.

[0037] According to some embodiments of the present disclosure, when the positive electrode material of the battery 100 is a compound having an olivine structure, S and V are 0.3 mm-1 ≦5000×S / V≦5mm -1 Such a configuration allows the battery 100 to have excellent electrochemical performance, for example, the battery 100 has a high capacity by using a compound having an olivine structure as the positive electrode material of the battery 100. The S / V ratio multiplied by 5000 is 0.3 mm -1 If the S / V ratio is less than 5 mm, the opening area 24 has a small area, which may cause the battery 100 to be unable to timely release the gas inside the battery 100. -1 If it is larger, the opening area 24 will have a large area, which may reduce the structural strength of the explosion-proof valve 20 and affect the safe use of the battery 100. Therefore, the 0.3 mm -1 ≦5000×S / V≦5mm -1 By setting S and V to satisfy, the ratio of the open area 24 to the volume of the battery 100 is appropriate, so that the pressure inside the battery 100 can be ensured to be released timely and quickly while the battery 100 has excellent electrochemical performance, thus improving the safety performance of the battery 100. The compound having an olivine structure may be, but is not limited to, lithium iron phosphate, lithium manganese iron phosphate, or a mixture of lithium iron phosphate and lithium manganese iron phosphate.

[0038] According to some other embodiments of the present disclosure, when the positive electrode material of the battery 100 comprises a layered compound, S and V are 0.5 mm -1 ≦5000×S / V≦6mm -1The layered lithium nickel-cobalt-manganese oxide ternary material has high activity. By using a highly active material such as a layered lithium nickel-cobalt-manganese oxide ternary material, a combination of lithium iron phosphate and a layered lithium nickel-cobalt-manganese oxide ternary material, or a combination of lithium iron manganese and a layered lithium nickel-cobalt-manganese oxide ternary material as the positive electrode material of the battery 100, the ratio of active materials in the battery 100 is relatively large, so that the energy of the battery 100 is larger and the electrochemical performance of the battery 100 is better, for example, the battery 100 has a higher capacity. Therefore, the battery 100 has a higher requirement for the pressure release speed of the explosion-proof valve 20. The S / V ratio multiplied by 5000 is 0.5 mm -1 If the S / V ratio is less than 6 mm, the opening area 24 has a small area, which may cause the battery 100 to be unable to release the gas inside the battery 100 as quickly as possible. -1 If it is larger than 0.5 mm, the opening area 24 will have a large area, which will reduce the safety performance of the battery 100. -1 ≦5000×S / V≦6mm -1 By setting S and V to satisfy the above, the ratio of the opening area 24 to the volume of the battery 100 is appropriate, so that the battery 100 has excellent charging and discharging performance, while ensuring that the internal pressure of the battery 100 is released in a timely and rapid manner, and the safe use of the battery 100 can be ensured.

[0039] In the following, description will be made with reference to comparative embodiments 1-2 (i.e., related art) and embodiments 1-12 (i.e., embodiments of the present disclosure). The battery 100 in comparative embodiments 1-2 and the battery 100 in embodiments 1-12 are tested by the method specified in GB / T 31485-2015, and the pressure release rate curves of the corresponding battery 100 are recorded. The battery in the related art is basically the same as the battery 100 in the embodiments of the present disclosure, but the values ​​of S and V are different.

[0040] When the positive electrode material of the battery 100 is lithium iron phosphate, the area S of the opening region 24 of the battery in Comparative Example 1 and the volume V of the battery 100, as well as the area S of the orthogonal projection of the opening region 24 of the battery 100 in Examples 1 to 6 and the volume V of the battery 100 are selected from Table 1 below. The test results of the pressure release speed are shown in Figures 7 and 8.

[0041] [Table 1]

[0042] Referring to Table 1, Figure 7, and Figure 8, Figure 7 is a curve showing the change in the gas pressure inside the battery in the embodiments 1 to 3 and the comparative embodiment 1 when the elevated pressure inside the battery is released, and Figure 8 is a curve showing the change in the gas pressure inside the battery in the embodiments 4 to 6 and the comparative embodiment 1 when the elevated pressure inside the battery is released. It can be understood from the curves that the gas pressure drop of the battery 100 in the embodiments 1 to 6 per unit time is larger than the gas pressure drop of the battery 100 in the comparative embodiment 1.

[0043] When the positive electrode material of the battery 100 is a layered lithium nickel cobalt manganese oxide ternary material, the area S of the orthogonal projection of the opening region 24 of the battery 100 in the comparative embodiment 2 and the volume V of the battery 100 in the embodiments 7 to 12 are selected from Table 2 below. The test results of the pressure release rate are shown in Figures 9 and 10.

[0044] [Table 2]

[0045] Referring to Table 2, Fig. 9, and Fig. 10, Fig. 9 is a curve showing the change in the gas pressure inside the battery 100 in the embodiments 7 to 9 and the comparative embodiment 2 when the elevated pressure inside the battery is released. Fig. 10 is a curve showing the change in the gas pressure inside the battery 100 in the embodiments 10 to 12 and the comparative embodiment 2 when the elevated pressure inside the battery is released. It can be understood from the curve that the gas pressure drop of the battery 100 in the embodiments 7 to 12 per unit time is larger than the gas pressure drop of the battery 100 in the comparative embodiment 2.

[0046] Therefore, as shown in embodiments 1 to 12, the range of values ​​of 5000×S / V claimed in the practice of the present disclosure can effectively increase the area of ​​the opening region 10, improve the amount of exhaust passing through the explosion-proof valve 20 per unit time, and enhance the safety performance of the battery 100 using the explosion-proof valve 20 of the present disclosure.

[0047] In some embodiments, S is 80 mm 2 ≦S≦1600mm 2 The area of ​​the orthogonal projection of the opening region 24 is 80 mm 2 If the area of ​​the orthogonal projection of the opening region 24 is less than 1600 mm , the opening region 24 has a small area, which may cause the battery 100 to be unable to release the gas inside the battery 100 as quickly as possible.2 If it is larger, the open area 24 will have a large area which may reduce the structural strength of the explosion-proof valve 20 .

[0048] In some embodiments, V is 40000 mm 3 ≦V≦3500000mm 3 The volume of the battery 100 is 40000 mm 3 If the volume of the battery 100 is less than 3.5 million mm, the volume of the battery 100 is small and the chemical performance of the battery 100 is insufficient. 3 If it is larger, the volume of the battery 100 will be large, which may reduce the structural strength of the explosion-proof valve 20 and cause the safety performance of the battery 100 to be reduced.

[0049] Therefore, S and V are 80 mm 2 ≦S≦1600mm 2 and 40000mm 3 ≦V≦3500000mm 3 Therefore, the opening area 24 has an appropriate area, and improves the pressure release speed of the explosion-proof valve 20 while ensuring the structural strength of the explosion-proof valve 20. In addition, the battery 100 has an appropriate volume, and therefore it is ensured that the built-up pressure inside the battery 100 is released in a timely and rapid manner while the battery 100 has excellent charging and discharging performance, and the safe use of the battery 100 can be ensured.

[0050] According to some embodiments of the present disclosure, the notch groove 25 is a C-shaped notch groove or two Y-shaped notch grooves. The pattern of the notch groove 25 is not limited to the above shapes, and any shape of the notch groove 25 can be used. The notch groove 25 can be designed to meet various usage occasions as needed.

[0051] According to some specific embodiments of the present disclosure, referring to Figs. 3 and 4, the notch groove 25 is a C-shaped notch groove. The notch groove 25 includes two oppositely arranged first arc segments 251, a first straight line segment 252, and two spaced apart second straight line segments 253. The first straight line segment 252 is arranged parallel to the second straight line segment 253, and two ends of the first straight line segment 252 are respectively connected to the two first arc segments 251. Each second straight line segment 253 is connected to a corresponding first arc segment 251. In other words, the first straight line segment 252 connects one end of the two first arc segments 251, and the other ends of the two first arc segments 251 are respectively connected to one second straight line segment 253, and the two second straight line segments 253 are arranged spaced apart. In the depth direction of the notched groove 25, the two free ends of the outer edge of the orthogonal projection of the notched groove 25 are connected to form a connecting line 263. That is, the connecting line between the edges of the two second straight line segments 253 on the side away from the center of the explosion-proof valve is the connecting line 263. The connecting line 263 and the outer edge of the orthogonal projection of the notched groove 25 together form a predetermined opening boundary. In this case, the area of ​​the region defined by the predetermined opening boundary (i.e., the area of ​​the orthogonal projection of the opening region 24 in the depth direction of the notched groove 25) is S c And S c = a1 × b1 + π × b1 2 / 4, and the total length of the notched groove 25 is L c And L c =2a1-c1+πb1, where a1 represents the length of the first straight line segment 252, b1 represents the distance between the outside of the first straight line segment 252 and the outside of the second straight line segment 253, and c1 represents the distance between the two second straight line segments 253, i.e., the length of the connecting line 263.

[0052] Furthermore, the cross section of the knurled groove 25 may be rectangular or inverted trapezoid. The "cross section" in this specification is a plane parallel to the depth direction of the knurled groove 25. When the cross section of the knurled groove 25 is an inverted trapezoid, the width of the knurled groove 25 gradually decreases toward the groove bottom of the knurled groove 25. In this case, a1 can be understood as the length of the outer edge of the first straight line segment 252 at the groove top or opening, and b1 can be understood as the diameter of the outer edge of the first arc segment 251 at the groove top or opening. In other words, in the depth direction of the knurled groove 25 (i.e., the direction from the groove opening to the groove bottom of the knurled groove 25), the outer edge of the orthogonal projection of the knurled groove 25 includes two opposing semicircles, b1 can be understood as the diameter of the semicircles, and a1 can be understood as the distance between the centers of the two semicircles.

[0053] In some embodiments, as shown in FIG. 4, the notch groove 25 is a C-shaped notch groove. A first reinforcing groove 29 having a structural reinforcing effect is further disposed in the opening region 24. The first reinforcing groove 29 is X-shaped. The first reinforcing groove 29 includes two fourth arc segments 260. The two fourth arc segments 260 are symmetrically disposed in the width direction of the explosion-proof valve (e.g., the vertical direction in FIG. 4), and the vertices of the two fourth arc segments 260 coincide. Two ends of one fourth arc segment 260 extend and contact the second straight segment 253, and two ends of the other fourth arc segment 260 extend and contact the first straight segment 252, respectively. In the depth direction of the notch groove 25, the depth of the first reinforcing groove 29 is smaller than the depth of the notch groove 25. In this case, the area of ​​the region defined by the predetermined opening boundary (i.e., the area of ​​the orthogonal projection of the opening region 24 in the depth direction of the notched groove 25) is S x And S x =S c =a2×b2+π×b2 2 / 4, and the total length of the notched groove 25 is L x And L x =L c=2a2-c2+πb2, where a2 represents the length of the first straight line segment 252, b2 represents the distance between the outside of the first straight line segment 252 and the outside of the second straight line segment 253, and c2 represents the distance between the two second straight line segments 253.

[0054] Furthermore, the cross section of the knurled groove 25 may be rectangular or inverted trapezoid. The "cross section" in this specification is a plane parallel to the depth direction of the knurled groove 25. When the cross section of the knurled groove 25 is an inverted trapezoid, the width of the knurled groove 25 gradually decreases toward the groove bottom of the knurled groove 25. In this case, a2 can be understood as the length of the outer edge of the first straight line segment 252 at the groove top or opening, and b2 can be understood as the diameter of the outer edge of the first arc segment 251 at the groove top or opening. In other words, in the depth direction of the knurled groove 25 (i.e., the direction from the groove opening to the groove bottom of the knurled groove 25), the outer edge of the orthogonal projection of the knurled groove 25 includes two opposing semicircles, b2 can be understood as the diameter of the semicircles, and a2 can be understood as the distance between the centers of the two semicircles.

[0055] According to some specific embodiments of the present disclosure, as shown in FIG. 5, the notch groove 25 is a looped notch groove. A second reinforcing groove 290 having a structural reinforcing effect is further disposed in the opening region 24. The second reinforcing groove 290 is Y-shaped. The second reinforcing groove 290 is disposed inside the looped notch groove and connected to the looped notch groove. For example, the looped notch groove includes two oppositely disposed second circular arc segments 254 and two parallel disposed third straight line segments 255. The two ends of each third straight line segment 255 are respectively connected to the two first circular arc segments 254. The two third straight line segments 255 and the two second circular arc segments 254 form a closed loop structure. In the depth direction of the notch groove 25, the outer edge of the orthogonal projection of the notch groove 25 forms a predetermined opening boundary. The predefined opening boundary may be formed by the edges of the two third straight line segments 255 and the two second arc segments 254 on the side away from the center of the explosion-proof valve.

[0056] The second reinforcing groove 290 includes two eighth straight segments 261 and one ninth straight segment 262. One end of each of the two eighth straight segments 261 is connected to the ninth straight segment 262, and an included angle α is formed between the two eighth straight segments 261, and the other end of each of the two eighth straight segments 261 is connected to one third straight segment 255. The other end of the ninth straight segment 262 may be connected to the second arc segment 254. The corresponding thickness of the second reinforcing groove 290 in the opening region 24 may be smaller than the corresponding thickness of the loop-shaped notched groove. That is, the depth of the second reinforcing groove 290 is smaller than the depth of the notched groove. With such a configuration, when the pressure inside the battery 100 increases, the opening region 24 protrudes outward under the internal pressure of the battery 100. The second reinforcing groove 290 deforms to resist deformation of the opening region 24, thereby improving the structural strength and deformation resistance of the opening region 24, and effectively preventing improper opening of the explosion-proof valve 20. In this case, the area of ​​the region defined by the predetermined opening boundary (i.e., the area of ​​the orthogonal projection of the opening region 24 in the depth direction of the notched groove 25) is S y And S y =a3×b3+π×b3 2 / 4, and the total length of the notched groove 25 is L y And L y = 2c3 + d3, where a3 is the length of the third straight segment 255, b3 is the distance between the outsides of the two third straight segments 255, c3 is the length of the eighth straight segment 261, and d3 is the length of the ninth straight segment 262.

[0057] Furthermore, the cross section of the knurled groove 25 may be rectangular or inverted trapezoid. The "cross section" in this specification is a plane parallel to the depth direction of the knurled groove 25. When the cross section of the knurled groove 25 is an inverted trapezoid, the width of the knurled groove 25 gradually decreases toward the groove bottom of the knurled groove 25. In this case, a3 can be understood as the length of the outer edge of the third straight line segment 255 at the groove top or opening, and b3 can be understood as the diameter of the outer edge of the second arc segment 254 at the groove top or opening. In other words, in the depth direction of the knurled groove 25 (i.e., the direction from the groove opening to the groove bottom of the knurled groove 25), the outer edge of the orthogonal projection of the knurled groove 25 includes two opposing semicircles, b3 can be understood as the diameter of the semicircles, and a3 can be understood as the distance between the centers of the two semicircles.

[0058] According to some specific embodiments of the present disclosure, referring to FIG. 6, the notch groove 25 is two Y-shaped notch grooves. When the pressure inside the battery 100 increases and needs to be released, the internal pressure can be released from the two Y-shaped notch grooves, so that the opening area 24 is inverted to realize pressure release. For example, the two Y-shaped notch grooves include a fourth straight segment 256 and four fifth straight segments 257. The two ends of the fourth straight segment 256 are respectively connected to the two fifth straight segments 257 arranged at a preset included angle. In the depth direction of the notch groove 25, a circular arc segment 259 is defined between the free ends of the orthogonal projections of the two fifth straight segments 257 arranged at the same end of the fourth straight segment 256. The circular arc segment 259 has the apex of the included angle preset between the two fifth straight segments 257 as the center of a circle. A sixth straight line segment 258 is defined between the free ends of the orthogonal projections of the two fifth straight line segments 257 located on the same side of the fourth straight line segment 256. The two arc-shaped segments 259 and the two sixth straight line segments 258 together form a predefined aperture boundary. It should be understood that the arc-shaped segment 259 and the sixth straight line segment 258 approximately intersect at one point, since the widths of the fourth straight line segment 256 and the fifth straight line segment 257 are relatively small and can be neglected. The arc-shaped segment 259 can be understood as being defined by the free ends of the orthogonal projections of the two fifth straight line segments 257 on the same end of the fourth straight line segment 256 that are close to each other. The sixth straight line segment 258 can be understood as being defined by the free ends of the orthogonal projections of the two fifth straight line segments 257 on the same side of the fourth straight line segment 256 that are close to each other.

[0059] In this case, the area of ​​the region defined by the predetermined opening boundary (i.e., the area of ​​the orthogonal projection of the opening region 24 in the depth direction of the notched groove 25) is S two-y and

[0060]

number

[0061] Therefore, the structural strength of the opening area 24 can be changed by different shapes of the notch groove 25. According to different design standards, a suitable notch groove 25 can be selected, thus reducing the difficulty of the process of the explosion-proof valve 20, improving the pressure release speed of the explosion-proof valve 20, and improving the safety performance of the battery 100.

[0062] Furthermore, the cross section of the notched groove 25 may be rectangular or inverted trapezoid. The "cross section" in this specification is a plane parallel to the depth direction of the notched groove 25. When the cross section of the notched groove 25 is an inverted trapezoid, the width of the notched groove 25 gradually decreases toward the groove bottom of the notched groove 25. In this case, a4 can be understood as the length of the outer edge of the fourth straight segment 256 at the groove top or opening, b4 is the distance between the free ends F of the two fifth straight segments 257 arranged on the same side of the fourth straight segment 256 at the groove top or opening, and c4 is the length of the outer edge of the fifth straight segment 257 at the groove top or opening.

[0063] According to some specific embodiments of the present disclosure, as shown in FIG. 2, the explosion-proof valve 20 includes a connection segment 21, a support segment 22, and a buffer segment 23. The explosion-proof valve 20 is connected to the battery shell 10 by the connection segment 21. The connection segment 21 is connected to the outer periphery of the support segment 22, and the support segment 22 and the connection segment 21 are spaced apart along the thickness direction of the support segment 22. The buffer segment 23 is connected between the connection segment 21 and the support segment 22, and the opening area 24 is disposed in the support segment 22. Therefore, the connection segment 21 allows the explosion-proof valve 20 to be fixedly connected to the battery shell 10, and the support segment 22 can increase the structural strength of the opening area 24 and prevent the torsional deformation of the opening area 24 caused by external force. In addition, by disposing the buffer segment 23 between the connection segment 21 and the support segment 22, the buffer segment 23 can absorb the thermal stress generated when the opening area 24 is welded to the support segment 22, so as to improve the reliability and safety of the explosion-proof valve 20.

[0064] Optionally, the support segment 22 is disposed on a side of the connection segment 21 adjacent to the center of the battery shell 10 so that the explosion-proof valve 20 is normally retracted toward the inside of the battery 100. This can effectively prevent improper opening of the opening area 24 caused by the impact of the opening area 24 by an external force.

[0065] According to some specific embodiments of the present disclosure, as shown in Fig. 2, a recess 221 is formed in the support segment 22, and a notch groove 25 is formed on the bottom wall of the recess 221. Therefore, the support segment 22 can further provide protection for the open area 24. Meanwhile, when the pressure inside the explosion-proof valve 20 increases and needs to be released, the open area 24 is thinned to promote the normal opening of the open area 24, thus preventing the failure of the explosion-proof valve 20.

[0066] Furthermore, the thickness of the open area 24 may vary in the depth direction of the notched groove 25. For example, the thickness of the middle area of ​​the open area 24 is smaller than the thickness of the edge, thereby ensuring the strength of the connection of the open area 24 with the support segment 22 and reducing the manufacturing cost of the open area 24.

[0067] According to some specific embodiments of the present disclosure, in the depth direction of the notched groove 25, the outer edge of the orthogonal projection of the recess 221 has an area overlapped with the outer edge of the orthogonal projection of the notched groove 25. That is, the notched groove 25 is provided on the outer edge of the bottom wall of the recess 221. Therefore, the area of ​​the orthogonal projection of the opening region 24 is maximized, thereby improving the pressure release capability of the explosion-proof valve 20.

[0068] According to some optional embodiments of the present disclosure, the explosion-proof valve 20 may have an elliptical or racetrack shape. With such a configuration, the explosion-proof valve 20 can be well adapted to the battery shell 10, for example, to the shape of the cover plate of the battery shell 10. When the explosion-proof valve 20 used has an elliptical or racetrack shape, the exhaust volume through the explosion-proof valve 20 in a unit time is larger, and the pressure release speed is better.

[0069] As shown in Figs. 11-12, according to some embodiments of the present disclosure, the explosion-proof valve 20 has a plate-like structure. The recess 221 is formed on the plate-like structure, and the notch groove 25 is provided on the outer edge of the bottom wall of the recess 221. With such a configuration, when the pressure inside the battery 100 increases and needs to be released, the explosion-proof valve 20 having the plate-like structure is easy to deform, and the gas inside the battery 100 can be released along the opening area 24 defined along the notch groove 25, so that the explosion-proof valve 20 can be well fitted to the battery shell 10 and realize rapid pressure release.

[0070] Optionally, the energy density of the battery 100 is ED, and ED satisfies 200wh / kg≦ED≦280wh / kg. With such a configuration, the energy density of the battery 100 is large, and the battery 100 has more active materials or more highly active materials. Therefore, in order to ensure that the explosion-proof valve 20 can be opened in a timely manner under extreme conditions while the battery 100 has better electrochemical performance, and to prevent the explosion-proof valve 20 from being inappropriately opened, the exhaust volume through the explosion-proof valve 20 in the battery 100 needs to be more accurately designed.

[0071] 13 and 14, a battery module 200 according to an embodiment in the second aspect of the present disclosure includes a battery 100 according to an embodiment in the first aspect. The battery module 200 includes a plurality of batteries 100 arranged side by side. The plurality of batteries 100 are connected in series or parallel. In the description of the present disclosure, "plurality" means two or more. Thus, by using the batteries 100 as described above in the battery module 200, the safety performance of the battery module 200 can be improved. The battery module 200 may further include two end plates (not shown) and two side plates (not shown). The two end plates are distributed on two ends of the plurality of batteries 100 along a first direction, and the two side plates are distributed on two sides of the plurality of batteries 100 along a second direction. The end plates and the side plates are connected to fix the battery 100, and the first direction is perpendicular to the second direction. Indeed, in other embodiments, the battery module 200 may further include two end plates and straps (not shown), which are distributed at two ends of the plurality of batteries 100 and secured by the straps.

[0072] According to the battery module 200 according to the embodiment of the present disclosure, the battery module 200 has high safety performance and long service life.

[0073] 13 and 14, a battery pack 300 according to an embodiment of the third aspect of the present disclosure includes the battery 100 according to the embodiment of the first aspect of the present disclosure or the battery module 200 according to the embodiment of the second aspect of the present disclosure. The battery pack 300 includes a tray (not shown). The battery 100 or the battery module 200 is fixed to the tray, and the tray is configured to fix the battery pack 300 to a vehicle 400. The battery 100 according to the above embodiments can be placed directly on the tray, or the battery module 200 according to the above embodiments is fixed to the tray.

[0074] According to the battery pack 300 according to the embodiment of the present disclosure, the explosion-proof valve 20 of the battery 100 in the battery module 200 can be disposed near the bottom of the battery module 200, so that the gas flow can be prevented from rushing into the inside of the vehicle body during the pressure release of the heated battery 100, and secondary danger can be prevented. Therefore, the stability when the battery pack 300 is used is improved.

[0075] 13-15, a vehicle 400 according to an embodiment in the fourth aspect of the present disclosure includes the battery 100 according to the embodiment in the first aspect described above, or includes the battery pack 300 according to the embodiment in the third aspect of the present disclosure. Thus, the possibility of explosion and combustion of the vehicle 400 is reduced, thereby improving the safety performance of the vehicle 400. For example, in some embodiments, the battery 100 may be directly attached to the vehicle 400. In some other embodiments, the battery 100 is assembled into the battery pack 300, and the battery pack 300 is attached to the vehicle 400.

[0076] In the description herein, references to terms such as "embodiments," "some embodiments," "example embodiments," "examples," "particular examples," or "some examples" mean that the particular feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of the disclosure. In the description herein, exemplary references to such terms do not necessarily refer to the same embodiment or example.

[0077] In the present disclosure, a "first feature" and a "second feature" may include one or more features. In the present disclosure, "multiple" means two or more. In the present disclosure, a first feature being "on" or "under" a second feature may include the first and second features being in direct contact, or the first and second features not in direct contact but in contact with other features between them. In the present disclosure, a first feature being "on", "above", or "over" a second feature may include the first feature being directly above or diagonally above the first feature, or may simply indicate that the height of the first feature is greater than the height of the second feature.

[0078] 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 can be made to the embodiments without departing from the principles and spirit of the present disclosure, the scope of which is as defined by the appended claims and their equivalents. [Explanation of symbols]

[0079] 100 Battery 10 Battery Shell 20 Explosion-proof valve 21 Connection Segments 22 Support Segments 23 Buffer Segment 221 Recess 24 Opening area 25 Notched groove 251 First Arc Segment 252 First Line Segment 253 Second Line Segment 254 Second Arc Segment 255 third line segment 256 Fourth Line Segment 257 Fifth Line Segment 258 Sixth Line Segment 259 Circular Segment 260 Fourth Arc Segment 261 8th straight line segment 262 9th straight segment 263 Connecting Line 27 Seventh straight segment 28 Third Arc Segment 29 First Reinforcement Groove 290 Second Reinforcement Groove 200 Battery Module 300 Battery Pack 400 vehicles

Claims

1. A battery shell (10); A battery (100) comprising an explosion-proof valve (20), the explosion-proof valve (20) being disposed in the battery shell (10), and the battery (100) being rated at 100 / mm ３ The explosion-proof valve (20) has a volume V in units of mm, the explosion-proof valve (20) is provided with a notched groove (25), the explosion-proof valve (20) has an opening region (24), and in the depth direction of the notched groove (25), the outer edge of the orthogonal projection of the opening region (24) is a predetermined opening boundary, and the area of ​​the orthogonal projection of the opening region (24) is mm ２ The unit is S, and S and V are 0.3 mm －１ A battery (100) that satisfies ≦(5000×S) / V.

2. S and V are (5000 x S) / V≦6 mm －１ The battery (100) of claim 1 ,

3. When the positive electrode material of the battery (100) is a compound having an olivine structure, S and V are 0.3 mm －１ ≦(5000×S) / V≦5mm －１ Further satisfying When the positive electrode material of the battery (100) comprises a layered compound, S and V are 0.5 mm －１ ≦(5000×S) / V≦6 mm －１ The battery (100) of claim 1 or 2, further comprising:

4. S is 80mm ２ ≦S≦1600mm ２ The battery (100) of any one of claims 1 to 3, wherein

5. V is 40,000 mm ３ ≦V≦3500000 mm ３ The battery (100) of any one of claims 1 to 4, wherein

6. the notched groove (25) comprises two oppositely disposed first circular arc segments (251), a first straight line segment (252) and two spaced apart second straight line segments (253), the first straight line segment (252) is disposed parallel to the second straight line segment (253), two ends of the first straight line segment (252) are connected to the two first circular arc segments (251), respectively, and each second straight line segment (253) is connected to a corresponding first circular arc segment (251); 6. The battery (100) according to claim 1, wherein in the depth direction of the notched groove (25), two free ends of an outer edge of the orthogonal projection of the notched groove (25) are connected to form a connection line (263), and the connection line (263) and the outer edge of the orthogonal projection of the notched groove (25) together form a predetermined opening boundary.

7. 7. The battery (100) of claim 6, wherein a first reinforcing groove (29) is disposed in the opening region (24), the first reinforcing groove (29) comprises two fourth arc segments (260), the two fourth arc segments (260) are disposed symmetrically along a width direction of the explosion-proof valve (20), the vertices of the two fourth arc segments (260) coincide, and two ends of one fourth arc segment (260) extend to the second straight segment (253), and two ends of the other fourth arc segment (260) extend to the first straight segment (252).

8. 8. The battery (100) of claim 7, wherein in the depth direction of the notched groove (25), the depth of the first reinforcing groove (29) is smaller than the depth of the notched groove (25).

9. the notched groove (25) comprises two oppositely disposed second circular arc segments (254) and two parallel disposed third straight line segments (255), two ends of each third straight line segment (255) are respectively connected to the two first circular arc segments (254), and the two third straight line segments (255) and the two second circular arc segments (254) form a closed loop structure; 6. The battery (100) according to claim 1, wherein in the depth direction of the notched groove (25), the outer edge of the orthogonal projection of the notched groove (25) forms the predetermined opening boundary.

10. 10. The battery of claim 9, wherein a second reinforcing groove (290) is disposed in the opening region (24), the second reinforcing groove (290) comprising two eighth straight segments (261) and one ninth straight segment (262), one end of each of the two eighth straight segments (261) being connected to the ninth straight segment (262), an included angle being formed between the two eighth straight segments (261), the other ends of the two eighth straight segments (261) extending to the two third straight segments (255), respectively, and the other end of the ninth straight segment (262) being connected to the second arc segment (254).

11. the notched groove (25) comprises a fourth straight segment (256) and four fifth straight segments (257), two ends of the fourth straight segment (256) being connected to two fifth straight segments (257) respectively, the fifth straight segments (257) being arranged at a preset included angle; 6. The battery (100) according to claim 1, wherein in the depth direction of the notched groove (25), an arc-shaped segment (259) is defined between free ends of an orthogonal projection of two fifth straight line segments (257) arranged on the same end of the fourth straight line segment (256), the arc-shaped segment (259) having a vertex of the preset included angle as a center of a circle, and a sixth straight line segment (258) is defined between free ends of an orthogonal projection of two fifth straight line segments (257) arranged on the same side of the fourth straight line segment (256), the two arc-shaped segments (259) and the two sixth straight line segments (258) together forming the predetermined opening boundary.

12. 12. The battery (100) according to claim 1, wherein the explosion-proof valve (20) comprises a connection segment (21), a support segment (22), and a buffer segment (23), the connection segment (21) is connected to an outer circumferential side of the support segment (22), the support segment (22) and the connection segment (21) are arranged at intervals along the thickness direction of the support segment (22), the buffer segment (23) is connected between the connection segment (21) and the support segment (22), and the opening area (24) is arranged in the support segment (22).

13. 13. The battery (100) according to any one of claims 1 to 12, wherein the explosion-proof valve (20) is formed with a recess (221), and the notched groove (25) is formed in a bottom wall of the recess (221).

14. 14. The battery (100) of claim 13, wherein in the depth direction of the notched groove (25), an outer edge of an orthogonal projection of the recess (221) has an area superimposed with the outer edge of the orthogonal projection of the notched groove (25).

15. 15. The battery (100) of any one of claims 1 to 14, wherein the explosion-proof valve (20) has an oval or racetrack shape.

16. 16. The battery (100) of any one of claims 1 to 15, wherein the anti-explosion valve (20) has a plate-like structure.

17. 17. The battery (100) of claim 1, wherein the energy density of the battery (100) is ED, where ED satisfies 200wh / kg≦ED≦280wh / kg.

18. A battery module (200) comprising the battery (100) according to any one of claims 1 to 17.

19. A battery pack (300) comprising the battery (100) according to any one of claims 1 to 17 or the battery module (200) according to claim 18.

20. A vehicle (400) comprising the battery (100) of any one of claims 1 to 17 or the battery pack (300) of claim 19.

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