Electrochemical devices and electrical equipment

Abstract

An electrochemical device (100) and an electrical equipment, wherein the electrochemical device (100) comprises a housing (10) and an electrode assembly (20). The electrode assembly (20) is arranged in the housing (10), and comprises a first pole piece (21), a second pole piece (22), and a diaphragm (23) arranged between the first pole piece (21) and the second pole piece (22). Along a first direction (X), the projection of the second pole piece (22) is located within the projection of the first pole piece (21), the projection of the first pole piece (21) is located within the projection of the diaphragm (23), and the projection of the diaphragm (23) is located within the projection of the cavity space (13). In a direction perpendicular to the first direction (X), the diaphragm (23) extends beyond the first pole piece (21), and the portion of the diaphragm (23) that extends beyond the first pole piece (21) and the shell (10) are enclosed to form a first area, thereby preventing the diaphragm (23) from entering the packaging area of ​​the shell (10), reducing the influence of the diaphragm (23) on the packaging of the shell (10), and improving the yield rate of the electrochemical device (100).

Description

Technical Field

[0001] The present application relates to the field of battery cell technology, and in particular to an electrochemical device and electrical equipment. Background Art

[0002] At present, in order to meet the safety requirements of electrode assemblies, the diaphragms in electrode assemblies are generally longer and extend beyond a certain distance. When the electrode assembly is placed in a shell for packaging, there is a risk that the ends of some diaphragms will enter the shell packaging area, which may lead to failure of the shell packaging. Summary of the invention

[0003] In view of the above situation, it is necessary to provide an electrochemical device to reduce the influence of the diaphragm on the shell packaging.

[0004] An embodiment of the present application provides an electrochemical device, including a shell and an electrode assembly. The shell includes a first shell and a second shell, and the first shell and the second shell are connected to each other to form a cavity space. The electrode assembly is arranged in the cavity space, and the electrode assembly includes a first pole piece, a second pole piece and a diaphragm arranged between the first pole piece and the second pole piece. The first pole piece, the diaphragm and the second pole piece are stacked and arranged in sequence along a first direction, and the first direction is the thickness direction of the shell. The first shell and the second shell are arranged relatively along the first direction. Along the first direction, the projection of the second pole piece is located within the projection of the first pole piece, the projection of the first pole piece is located within the projection of the diaphragm, and the projection of the diaphragm is located within the projection of the cavity space. In a direction perpendicular to the first direction, the diaphragm exceeds the first pole piece, and the portion of the diaphragm that exceeds the first pole piece is surrounded by the first shell and the second shell to form a first area.

[0005] The diaphragm of the electrochemical device is arranged in the cavity space of the shell, and the part of the diaphragm that protrudes beyond the first pole piece and the second pole piece is surrounded by the first shell and the second shell to form a first area, which can prevent the diaphragm from entering the connection area between the first shell and the second shell, reduce the influence of the diaphragm on the shell packaging, and improve the yield rate of the electrochemical device.

[0006] In some embodiments of the present application, along the first direction, the projection of the first region is located within the projection of the diaphragm, and the length of the first region (i.e., the maximum length of the first region in the first direction) is L1, and L1>0. Along the direction perpendicular to the first direction, the width of the first region (i.e., the maximum width of the first region in the direction perpendicular to the first direction) is W1, and W1>0.

[0007] In some embodiments of the present application, along the first direction, starting from the connection area between the first shell and the second shell, the width of the first area gradually decreases in the direction away from the connection area; along the direction perpendicular to the first direction, the maximum length of the diaphragm extending beyond the first pole piece is W, W>2*W1.

[0008] In some embodiments of the present application, along the first direction, the length of the cavity space is H, and H≥2*L1.

[0009] In some embodiments of the present application, along a direction perpendicular to the first direction, the minimum distance between the first region and the first pole piece is D, and D≥0.45 mm, which can reduce the risk of short circuit between the first pole piece and the second pole piece and improve the safety performance of the electrode assembly.

[0010] In some embodiments of the present application, the diaphragm is connected to the first shell and / or the second shell in a direction perpendicular to the first direction, which can reduce the risk of displacement of the electrode assembly relative to the shell and improve the seismic resistance of the electrochemical device.

[0011] In some embodiments of the present application, the electrochemical device further includes an adhesive, one end of the adhesive is connected to one end of the electrode assembly along the first direction, and the other end of the adhesive is connected to the other end of the electrode assembly along the first direction. The adhesive can be used to reinforce the electrode assembly, reduce the risk of relative displacement of the first pole piece, the second pole piece and the diaphragm, and improve the seismic performance of the electrochemical device. In a direction perpendicular to the first direction, the end of the diaphragm abuts the adhesive. In the first direction, the projection of the adhesive is located within the projection of the cavity space. The adhesive and the first shell and the second shell are surrounded to form a second area, and the second area is located in the first area, which can reduce the influence of the adhesive on the shell packaging and improve the yield rate of the electrochemical device.

[0012] In some embodiments of the present application, along a direction perpendicular to the first direction, the projection of the second area is located within the projection of the adhesive, and part of the adhesive abuts against the first shell and / or the second shell, which can reduce the risk of displacement of the electrode assembly relative to the shell and improve the seismic resistance of the electrochemical device.

[0013] In some embodiments of the present application, the number of the first pole piece, the diaphragm, and the second pole piece is multiple, and at least one diaphragm is provided between any adjacent first pole pieces and second pole pieces. Along the first direction, both ends of the electrode assembly are first pole pieces, and both ends of the adhesive are respectively connected to the first pole pieces at both ends of the electrode assembly. Both ends of the electrode assembly are first pole pieces, so that ions can penetrate at any position on the second pole piece, thereby improving the energy density of the electrochemical device.

[0014] The embodiment of the present application also provides an electrical device, comprising the electrochemical device described in any of the above embodiments. The diaphragm of the above electrochemical device is arranged in the cavity space of the shell, and the portion of the diaphragm that exceeds the first pole piece and the second pole piece is surrounded by the first shell and the second shell to form a first area, which can prevent the diaphragm from entering the connection area of ​​the first shell and the second shell, reduce the influence of the diaphragm on the shell packaging, improve the yield rate of the electrochemical device, and reduce the influence of the electrochemical device on the electrical device due to quality problems. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of the structure of an electrochemical device in one embodiment of the present application.

[0016] Figure 2 It is a schematic diagram of the structure of an electrode assembly in one embodiment of the present application.

[0017] Figure 3 yes Figure 1 Partial view of section II II II of the electrochemical device shown.

[0018] Figure 4 yes Figure 1 A schematic structural diagram of an expanded embodiment of the electrochemical device is shown.

[0019] Figure 5 yes Figure 1 A partial cutout of an expanded embodiment of the electrochemical device is shown.

[0020] Figure 6 It is a schematic structural diagram of an electrode assembly provided with an adhesive in one embodiment of the present application.

[0021] Figure 7 yes Figure 6 A partial structural cross-sectional view of an electrode assembly provided with an adhesive member encapsulated in a shell.

[0022] Figure 8 It is a schematic diagram of the structure of an electrical device in an embodiment of the present application.

[0023] Main component symbols

[0024] Electrochemical device 100

[0025] Housing 10

[0026] First housing 11

[0027] The first groove 111

[0028] First chamfer 112

[0029] Second housing 12

[0030] The second groove 121

[0031] Second chamfer 122

[0032] Cavity space 13

[0033] Connecting area 14

[0034] Injection hole 15

[0035] Electrode assembly 20

[0036] The first pole piece 21

[0037] The second pole piece 22

[0038] Diaphragm 23

[0039] First electrode terminal 24

[0040] Second electrode terminal 25

[0041] First output terminal 31

[0042] Second output terminal 32

[0043] First Area 40

[0044] Part 141

[0045] Part 242

[0046] Adhesive 50

[0047] Second area 60

[0048] Part 361

[0049] Part 462

[0050] Electrical equipment 200

[0051] First direction X

[0052] The following specific implementation methods will further illustrate the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0054] It should be noted that when an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be a centrally disposed element at the same time. When an element is considered to be "disposed on" another element, it may be directly disposed on the other element or there may be a centrally disposed element at the same time.

[0055] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which the present application belongs. The terms used herein in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0056] An embodiment of the present application provides an electrochemical device, including a shell and an electrode assembly. The shell includes a first shell and a second shell, and the first shell and the second shell are connected to each other to form a cavity space. The electrode assembly is arranged in the cavity space, and the electrode assembly includes a first pole piece, a second pole piece and a diaphragm arranged between the first pole piece and the second pole piece. The first pole piece, the diaphragm and the second pole piece are stacked and arranged in sequence along a first direction, and the first direction is the thickness direction of the shell. The first shell and the second shell are arranged relatively along the first direction. Along the first direction, the projection of the second pole piece is located within the projection of the first pole piece, the projection of the first pole piece is located within the projection of the diaphragm, and the projection of the diaphragm is located within the projection of the cavity space. In a direction perpendicular to the first direction, the diaphragm exceeds the first pole piece, and the portion of the diaphragm that exceeds the first pole piece is surrounded by the first shell and the second shell to form a first area.

[0057] The diaphragm of the electrochemical device is arranged in the cavity space of the shell, and the part of the diaphragm that protrudes beyond the first pole piece and the second pole piece is surrounded by the first shell and the second shell to form a first area, which can prevent the diaphragm from entering the connection area between the first shell and the second shell, reduce the influence of the diaphragm on the shell packaging, and improve the yield rate of the electrochemical device.

[0058] The embodiments of the present application are further described below in conjunction with the accompanying drawings.

[0059] like Figure 1 , Figure 2 and Figure 3 As shown, an embodiment of the present application provides an electrochemical device 100, including a housing 10 and an electrode assembly 20, wherein the electrode assembly 20 is disposed in the housing 10. The electrode assembly 20 includes a first electrode sheet 21, a second electrode sheet 22, a diaphragm 23, a first electrode terminal 24, and a second electrode terminal 25, wherein the diaphragm 23 is disposed between the first electrode sheet 21 and the second electrode sheet 22, and the first electrode sheet 21, the diaphragm 23, and the second electrode sheet 22 are stacked in sequence along a first direction X, wherein the first direction X is the thickness direction of the housing 10. The first electrode terminal 24 is electrically connected to the first electrode sheet 21, and the second electrode terminal 25 is electrically connected to the second electrode sheet 22, and the first electrode terminal 24 and the second electrode terminal 25 are used to electrically connect an external device so that the electrochemical device 100 can be charged and discharged.

[0060] In one embodiment, a liquid injection hole 15 is provided on the shell 10 , and the liquid injection hole 15 is used to inject electrolyte into the shell 10 after the electrode assembly 20 is encapsulated in the shell 10 .

[0061] In one embodiment, the electrochemical device 100 further includes a first output terminal 31 and a second output terminal 32, wherein the first output terminal 31 is electrically connected to the first electrode terminal 24 and exposed from the shell 10, and the second output terminal 32 is electrically connected to the second electrode terminal 25 and exposed from the shell 10, and the first output terminal 31 and the second output terminal 32 are used to electrically connect to an external device so that the electrochemical device 100 can be charged and discharged.

[0062] In one embodiment, the electrochemical device 100 is a soft pack battery, and optionally, the housing 10 includes an aluminum plastic film. In one embodiment, the electrochemical device 100 is a hard shell battery, and optionally, the housing 10 includes a steel shell. As an example, the electrochemical device 100 is a hard shell battery, and the housing 10 includes a steel shell as an example for further description.

[0063] In one embodiment, the first output terminal 31 is located on the outer surface of the housing 10 and is electrically connected to the housing 10, and the first electrode terminal 24 is electrically connected to the housing 10 and thus electrically connected to the first output terminal 31. In one embodiment, the first output terminal 31 is welded to the outer surface of the housing 10. In one embodiment, the first electrode terminal 24 is welded to the inner surface of the housing 10. In one embodiment, the first output terminal 31 is a nickel sheet.

[0064] In one embodiment, part of the second output terminal 32 is located inside the housing 10 and connected to the second electrode terminal 25, and part of the second output terminal 32 is located outside the housing 10. The part of the second output terminal 32 located outside the housing 10 is used to connect an external device. The electrochemical device 100 also includes a second seal (not shown), which connects the second output terminal 32 and the housing 10. The second seal can prevent the second output terminal 32 from contacting the housing 10, reducing the risk of short circuit caused by the electrical connection between the second output terminal 32 and the housing 10. In one embodiment, the second output terminal 32 is a pole.

[0065] Please combine Figure 2 and Figure 4 In one embodiment, part of the first output terminal 31 is located inside the housing 10 and connected to the first electrode terminal 24, and part of the first output terminal 31 is located outside the housing 10. The first output terminal 31 located outside the housing 10 is used to connect an external device. The electrochemical device 100 further includes a first seal (not shown), which connects the first output terminal 31 and the housing 10. The first seal can prevent the first output terminal 31 from contacting the housing 10, thereby reducing the risk of short circuit caused by the electrical connection between the first output terminal 31 and the housing 10. In one embodiment, the first output terminal 31 is a pole.

[0066] As an example, the following further describes the first output terminal 31 as a nickel sheet and the second output terminal 32 as a pole.

[0067] Please combine Figure 1 and Figure 3 In one embodiment, one of the first electrode 21 and the second electrode 22 is a positive electrode, and the other is a negative electrode. As an example, the first electrode 21 is a negative electrode, and the second electrode 22 is a positive electrode for further description.

[0068] In one embodiment, the first pole piece 21 includes a first current collector and a first active material layer, and the first active material layer is disposed on the surface of the first current collector. Optionally, the first current collector is made of copper foil. Optionally, the first active material layer is made of graphite.

[0069] In one embodiment, the second electrode 22 includes a second current collector and a second active material layer, and the second active material layer is disposed on the surface of the second current collector. Optionally, the second current collector is made of aluminum foil. Optionally, the second active material layer is made of lithium cobalt oxide.

[0070] The shell 10 includes a first shell 11 and a second shell 12 . The first shell 11 and the second shell 12 are arranged opposite to each other along a first direction X. The first shell 11 and the second shell 12 are connected to each other to form a cavity space 13 . The electrode assembly 20 is arranged in the cavity space 13 .

[0071] In one embodiment, there are multiple first pole pieces 21, diaphragms 23 and second pole pieces 22, a diaphragm 23 is provided between any adjacent first pole pieces 21 and second pole pieces 22, and all first pole pieces 21, diaphragms 23 and second pole pieces 22 are stacked.

[0072] In one embodiment, along the first direction X, the outermost pole piece is the first pole piece 21 , and the first current collector of the outermost first pole piece 21 contacts the inner surface of the connection housing 10 .

[0073] In one embodiment, the first electrode terminal 24 connects all the first electrode sheets 21 . In one embodiment, the second electrode terminal 25 connects all the second electrode sheets 22 .

[0074] Along the first direction X, the projection of the second pole piece 22 is located within the projection of the first pole piece 21 , which can reduce the risk of lithium deposition.

[0075] Along the first direction X, the projection of the first pole piece 21 is located within the projection of the diaphragm 23, and along the direction perpendicular to the first direction X, the diaphragm 23 is beyond the first pole piece 21, which can reduce the risk of short circuit between the first pole piece 21 and the adjacent second pole piece 22. In the present application, the direction perpendicular to the first direction X refers to all directions on the plane perpendicular to the thickness direction of the housing 10.

[0076] Along the first direction X, the projection of the diaphragm 23 is located within the projection of the cavity space 13. Along the direction perpendicular to the first direction X, the portion of the multilayer diaphragm 23 that exceeds the first pole piece 21 is surrounded by the first shell 11 and the second shell 12 to form a first region 40. The presence of the first region 40 can reduce the risk of the diaphragm 23 entering the connection region 14 of the first shell 11 and the second shell 12, reduce the impact of the diaphragm 23 on the packaging of the shell 10, and improve the yield rate of the electrochemical device 100. In the present application, the connection region 14 of the first shell 11 and the second shell 12 refers to the region where the first shell 11 and the second shell 12 contact each other. When the shell 10 is packaged, the first shell 11 and the second shell 12 are usually sealed and connected in the connection region 14 of the first shell 11 and the second shell 12. If part of the diaphragm 23 enters the sealed connection region of the first shell 11 and the second shell 12, it may cause the sealing failure of the shell 10, thereby scrapping the electrochemical device 100.

[0077] In one embodiment, the first region 40 includes a first portion 41 and a second portion 42 . Along the first direction X, a projection of the first portion 41 is located inside a projection of the diaphragm 23 , and a projection of the second portion 42 is located outside the projection of the diaphragm 23 .

[0078] In one embodiment, taking the electrode assembly 20 as an object, along the direction perpendicular to the first direction X, the first portion 41 is formed by the end of the multilayer diaphragm 23 being recessed in a direction close to the first pole piece 21 and the second pole piece 22. In one embodiment, the first portion 41 is formed by shaping a portion of the diaphragm 23. Specifically, after all the first pole pieces 21, the diaphragms 23 and the second pole pieces 22 are stacked, a shaping process is used to form a recessed notch at the end of a portion of the diaphragm 23 to form the first portion 41. In one embodiment, the shaping process for the diaphragm 23 includes but is not limited to hot stamping, laser cutting, and mechanical cutting.

[0079] In one embodiment, the second part 42 is formed at the chamfered portion of the first shell 11 and / or the second shell 12. Along the direction perpendicular to the first direction X, one side of the second part 42 is the first part 41, and the other side of the second part 42 is the connection area 14 between the first shell 11 and the second shell 12.

[0080] In one embodiment, along the first direction X, the length of the first region 40 is L1 (i.e., the maximum length of the first region in the first direction), and L1>0. Along the direction perpendicular to the first direction X, the width of the first region 40 is W1 (i.e., the maximum width of the first region in the direction perpendicular to the first direction), and W1>0.

[0081] In one embodiment, along the first direction X, the maximum width of the first region 40 is located at the connection region 14 of the first shell 11 and the second shell 12, which can further reduce the risk of the diaphragm 23 entering the connection region 14. In addition, along the first direction X, starting from the connection region 14 of the first shell 11 and the second shell 12, the width of the first region 40 gradually decreases in the direction away from the connection region 14 until it becomes zero, so that the end of part of the diaphragm 23 can abut against the first shell 11 and / or the second shell 12, reducing the risk of relative displacement between the electrode assembly 20 and the shell 10, and improving the anti-seismic performance of the electrochemical device 100.

[0082] In one embodiment, along the first direction X, the length of the cavity space 13 is H, H ≥ 2*L1, so that more diaphragms 23 can be abutted against the first shell 11 and / or the second shell 12, reducing the risk of relative displacement between the electrode assembly 20 and the shell 10, and improving the anti-seismic performance of the electrochemical device 100. In one embodiment, H / 3 ≤ L1 ≤ H / 2. Optionally, L1 = H / 3.

[0083] In one embodiment, along the direction perpendicular to the first direction X, the minimum distance D between the first portion 41 and the first pole piece 21 is D, and D ≥ 0.45 mm, so that the portion of the diaphragm 23 extending beyond the first pole piece 21 can be isolated, thereby reducing the risk of short circuit between the first pole piece 21 and the adjacent second pole piece 22. In one embodiment, the minimum distance D between the first portion 41 and the first pole piece 21 is a safe length of the diaphragm 23 extending beyond the first pole piece 21. Optionally, the value of D is one of 0.45 mm, 0.5 mm, and 0.55 mm.

[0084] In one embodiment, along a direction perpendicular to the first direction X, the maximum length of the diaphragm 23 extending beyond the first pole piece 21 is W, W>D, W>2*W1, which can reduce the influence of the first region 40 on the safe length of the diaphragm 23 extending beyond the first pole piece 21.

[0085] In one embodiment, the second shell 12 has a second groove 121, and the first shell 11 covers the second shell 12, so that the second groove 121 forms a cavity space 13. Along the direction perpendicular to the first direction X, the projection of the cavity space 13 and the first area 40 is located within the projection of the second shell 12, and the end of part of the diaphragm 23 abuts against the second shell 12. In one embodiment, the portion of the second shell 12 between the cavity space 13 and the connection area 14 has a second chamfer 122, and along the first direction X, the second portion 42 is located between the second chamfer 122 and the first shell 11. In one embodiment, the second chamfer 122 is a rounded corner, which can reduce the impact of the second chamfer 122 on the diaphragm 23 and reduce the risk of the second chamfer 122 puncturing the diaphragm 23.

[0086] like Figure 5 As shown, in one embodiment, the first shell 11 has a first groove 111, the second shell 12 has a second groove 121, and the first shell 11 and the second shell 12 are buckled together to form a cavity space 13. Along the direction perpendicular to the first direction X, a portion of the cavity space 13 is projected within the projection of the first shell 11, and another portion is projected within the projection of the second shell 12, and a portion of the first area 40 is projected within the projection of the first shell 11, and another portion is projected within the projection of the second shell 12. In one embodiment, the first shell 11 has a first chamfer 112 at a location between the first groove 111 and the connection area 14, and the second shell 12 has a second chamfer 122 at a location between the second groove 121 and the connection area 14. Along the first direction X, the second portion 42 is located between the first chamfer 112 and the second chamfer 122.

[0087] In one embodiment, the first chamfer 112 is a rounded corner, which can reduce the impact of the first chamfer 112 on the diaphragm 23 and reduce the risk of the first chamfer 112 puncturing the diaphragm 23. In one embodiment, the second chamfer 122 is a rounded corner, which can reduce the impact of the second chamfer 122 on the diaphragm 23 and reduce the risk of the second chamfer 122 puncturing the diaphragm 23.

[0088] As an example, the following further describes the example in which the first shell 11 covers the second shell 12 and the second groove 121 forms the cavity space 13 .

[0089] Please continue reading Figure 3 In one embodiment, along a direction perpendicular to the first direction X, the diaphragm 23 abutting against the second shell 12 is in a squeezed and deformed state, which can further improve the stability of the electrode assembly 20 connected to the shell 10, reduce the risk of displacement of the electrode assembly 20 relative to the shell 10, and improve the seismic resistance of the electrochemical device 100.

[0090] In one embodiment, along the first direction X, the portions of the diaphragm 23 that are squeezed and deformed by the second shell 12 are bent toward the second portion 42, and along the direction perpendicular to the first direction X, the multiple diaphragms 23 in the bending area are stacked in sequence, which can reduce the risk of the ends of the first pole piece 21 and the second pole piece 22 puncturing part of the diaphragm 23 and then contacting the shell 10 to cause a short circuit, thereby improving the safety performance of the electrochemical device 100.

[0091] like Figure 6 and Figure 7As shown, in one embodiment, the electrochemical device 100 further includes an adhesive 50, one end of the adhesive 50 is connected to one end of the electrode assembly 20 along the first direction X, and the other end of the adhesive 50 is connected to the other end of the electrode assembly 20 along the first direction X. The adhesive 50 can improve the connection tightness of the electrode assembly 20 along the first direction X, reduce the risk of relative displacement between the first pole piece 21, the diaphragm 23 and the second pole piece 22, improve the seismic resistance of the electrode assembly 20, and improve the seismic resistance of the electrochemical device 100. Optionally, the adhesive 50 is an insulating tape.

[0092] In one embodiment, there are multiple adhesives 50, which are spaced apart from each other along the circumference of the electrode assembly 20, and can fasten the electrode assembly 20 at multiple locations, further improving the seismic resistance of the electrode assembly 20 and the seismic resistance of the electrochemical device 100.

[0093] In one embodiment, along a direction perpendicular to the first direction X, the end of the diaphragm 23 abuts against the adhesive 50 to prevent the adhesive 50 from loosening, thereby reducing the risk of relative displacement between the first pole piece 21, the diaphragm 23 and the second pole piece 22.

[0094] Please combine Figure 3 and Figure 6 In one embodiment, along the first direction X, the projection of the adhesive 50 is located within the projection of the cavity space 13. The adhesive 50, the first shell 11, and the second shell 12 are surrounded to form a second area 60, wherein the second area 60 is located within the first area 40, which can reduce the risk of the adhesive 50 entering the connection area 14, reduce the impact of the adhesive 50 on the packaging of the shell 10, and improve the yield rate of the electrochemical device 100.

[0095] In one embodiment, the second region 60 includes a third portion 61 and a fourth portion 62, wherein the third portion 61 constitutes part of the first portion 41, and the fourth portion 62 is the same as the second portion 42. Along the first direction X, the projection of the third portion 61 is located within the projection of the adhesive 50, and the projection of the fourth portion 62 is located outside the projection of the adhesive 50.

[0096] In one embodiment, after all the first electrode sheets 21, diaphragms 23, and second electrode sheets 22 are stacked, a shaping process is used to form a concave notch at the end of part of the diaphragm 23. After the electrode assembly 20 is placed in the shell 10, the concave notch formed at the end of the diaphragm 23 forms a first part 41. After the adhesive 50 is attached to the electrode assembly 20, a third part 61 is formed in the first part 41.

[0097] The fourth portion 62 is the same as the second portion 42 and will not be described again herein.

[0098] In one embodiment, along the first direction X, the length of the second region 60 is L2, where L2>0. Along a direction perpendicular to the first direction X, the width of the second region 60 is W2, where W2>0.

[0099] In one embodiment, along the first direction X, the maximum width of the second region 60 is located at the connection region 14 of the first shell 11 and the second shell 12, which can further reduce the risk of the diaphragm 23 and / or the adhesive member 50 entering the connection region 14. In addition, along the first direction X, starting from the connection region 14 of the first shell 11 and the second shell 12, the width of the second region 60 gradually decreases in the direction away from the connection region 14 until it becomes zero, so that the end of part of the adhesive member 50 can abut against the second shell 12, reduce the risk of relative displacement between the electrode assembly 20 and the shell 10, and improve the anti-seismic performance of the electrochemical device 100.

[0100] In one embodiment, L2≤H / 2, so that more adhesives 50 can be in contact with the second housing 12, reducing the risk of relative displacement between the electrode assembly 20 and the housing 10, and improving the anti-seismic performance of the electrochemical device 100. In one embodiment, H / 3≤L2≤H / 2. Optionally, L2=H / 3.

[0101] In one embodiment, along a direction perpendicular to the first direction X, the diaphragm 23 abutting against the adhesive 50 is in a state of being squeezed and deformed, which can further improve the connection stability of the first pole piece 21, the diaphragm 23 and the second pole piece 22, reduce the risk of relative displacement of the first pole piece 21, the diaphragm 23 and the second pole piece 22, improve the seismic resistance of the electrode assembly 20, and improve the seismic resistance of the electrochemical device 100.

[0102] In one embodiment, along the first direction X, the portions of the diaphragm 23 that are squeezed and deformed by the adhesive 50 are bent toward the fourth portion 62, and the multiple diaphragms 23 in the bending area are stacked in sequence along the direction perpendicular to the first direction X, which can reduce the risk of the ends of the first pole piece 21 and the second pole piece 22 puncturing part of the diaphragm 23 and the adhesive 50 and then contacting the shell 10 to cause a short circuit, thereby improving the safety performance of the electrochemical device 100.

[0103] In summary, the diaphragm 23 of the electrochemical device 100 of the present application is arranged in the cavity space 13 of the shell 10, and the portion of the diaphragm 23 that extends beyond the first pole piece 21 and the second pole piece 22 is surrounded by the first shell 11 and the second shell 12 to form a first area 40, which can prevent the diaphragm 23 from entering the connection area 14 of the first shell 11 and the second shell 12, reduce the impact of the diaphragm 23 on the packaging of the shell 10, and improve the yield rate of the electrochemical device 100.

[0104] like Figure 8As shown, an embodiment of the present application further provides an electrical device 200 , comprising the electrochemical device 100 described in any of the above embodiments, and the electrochemical device 100 can provide electrical energy to the electrical device 200 .

[0105] In one embodiment, the power-consuming device 200 includes but is not limited to a mobile phone, a computer, a tablet computer, a digital camera, a drone, and a new energy vehicle.

[0106] The electrical equipment 200 of the present application adopts the electrochemical device 100 described in any of the above embodiments, which can reduce the impact of the electrochemical device 100 on the electrical equipment 200 due to quality problems.

[0107] In addition, those skilled in the art may also make other changes within the spirit of the present application. Of course, these changes made according to the spirit of the present application should be included in the scope disclosed in the present application.

Claims

1. An electrochemical device, characterized in that include: The housing comprises a first housing and a second housing, wherein the first housing and the second housing are connected to each other to form a cavity space; an electrode assembly, disposed in the cavity space, the electrode assembly comprising a first electrode piece, a second electrode piece, and a diaphragm disposed between the first electrode piece and the second electrode piece, the first electrode piece, the diaphragm, and the second electrode piece are stacked in sequence along a first direction, the first direction is a thickness direction of the shell, and the first shell and the second shell are disposed opposite to each other along the first direction; Along the first direction, the projection of the second pole piece is located within the projection of the first pole piece, the projection of the first pole piece is located within the projection of the diaphragm, and the projection of the diaphragm is located within the projection of the cavity space; In a direction perpendicular to the first direction, the diaphragm extends beyond the first pole piece, and a portion of the diaphragm extending beyond the first pole piece is surrounded by the first shell and the second shell to form a first region; The width of the first region is W1. Along the first direction, starting from the connection region between the first shell and the second shell, the width W1 of the first region gradually decreases in a direction away from the connection region.

2. The electrochemical device according to claim 1, characterized in that Along the first direction, at least a portion of the projection of the first region is located within the projection of the diaphragm, and a length of the first region is L1, where L1>0; In a direction perpendicular to the first direction, W1>0.

3. The electrochemical device according to claim 2, characterized in that Along a direction perpendicular to the first direction, the maximum length of the diaphragm extending beyond the first pole piece is W, where W>2*W1.

4. The electrochemical device according to claim 2, characterized in that Along the first direction, the length of the cavity space is H, and H≥2*L1.

5. The electrochemical device according to claim 1, characterized in that Along a direction perpendicular to the first direction, a minimum distance between the first region and the first pole piece is D, and D≥0.45 mm.

6. The electrochemical device according to claim 1, wherein: The diaphragm is connected to the first shell and / or the second shell along a direction perpendicular to the first direction.

7. The electrochemical device according to claim 1, characterized in that Also included is an adhesive member, one end of the adhesive member is connected to one end of the electrode assembly along the first direction, and the other end of the adhesive member opposite to the other end of the electrode assembly along the first direction; Along a direction perpendicular to the first direction, an end of the diaphragm abuts against the adhesive member; Along the first direction, the projection of the adhesive is located within the projection of the cavity space; The adhesive component, the first shell and the second shell are arranged to form a second area, and the second area is located in the first area.

8. The electrochemical device according to claim 7, characterized in that Along a direction perpendicular to the first direction, a projection of the second area is located within a projection of the adhesive member, and a portion of the adhesive member abuts against the first shell and / or the second shell.

9. The electrochemical device according to claim 7, characterized in that There are multiple first pole pieces, multiple diaphragms and multiple second pole pieces, and at least one diaphragm is provided between any adjacent first pole pieces and second pole pieces; Along the first direction, both ends of the electrode assembly are the first pole pieces, and both ends of the adhesive are respectively connected to the first pole pieces at both ends of the electrode assembly.

10. An electrical device, characterized in that: Comprising the electrochemical device according to any one of claims 1 to 9.

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