WO2022032473A1 - 一种电化学装置及电子设备 - Google Patents

一种电化学装置及电子设备 Download PDF

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Publication number
WO2022032473A1
WO2022032473A1 PCT/CN2020/108396 CN2020108396W WO2022032473A1 WO 2022032473 A1 WO2022032473 A1 WO 2022032473A1 CN 2020108396 W CN2020108396 W CN 2020108396W WO 2022032473 A1 WO2022032473 A1 WO 2022032473A1
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WIPO (PCT)
Prior art keywords
wall surface
region
electrochemical device
area
stress
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PCT/CN2020/108396
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English (en)
French (fr)
Inventor
马聪
邓道林
周梦成
陈文�
Original Assignee
宁德新能源科技有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by 宁德新能源科技有限公司 filed Critical 宁德新能源科技有限公司
Priority to PCT/CN2020/108396 priority Critical patent/WO2022032473A1/zh
Priority to EP20948972.3A priority patent/EP4170803A4/en
Priority to CN202080013313.4A priority patent/CN113544890B/zh
Publication of WO2022032473A1 publication Critical patent/WO2022032473A1/zh
Priority to US18/108,268 priority patent/US20230198070A1/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/233—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by physical properties of casings or racks, e.g. dimensions
    • H01M50/242—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by physical properties of casings or racks, e.g. dimensions adapted for protecting batteries against vibrations, collision impact or swelling
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/14—Primary casings; Jackets or wrappings for protecting against damage caused by external factors
    • H01M50/143—Fireproof; Explosion-proof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/50—Current conducting connections for cells or batteries
    • H01M50/572—Means for preventing undesired use or discharge
    • H01M50/574—Devices or arrangements for the interruption of current
    • H01M50/578—Devices or arrangements for the interruption of current in response to pressure
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/102—Primary casings; Jackets or wrappings characterised by their shape or physical structure
    • H01M50/107—Primary casings; Jackets or wrappings characterised by their shape or physical structure having curved cross-section, e.g. round or elliptic
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/102—Primary casings; Jackets or wrappings characterised by their shape or physical structure
    • H01M50/109—Primary casings; Jackets or wrappings characterised by their shape or physical structure of button or coin shape
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present application relates to the technical field of energy storage devices, and in particular, to an electrochemical device and an electronic device.
  • a lithium ion battery is a rechargeable secondary battery.
  • lithium ions move between a positive electrode and a negative electrode, and are intercalated or deintercalated from the electrodes to generate electrical energy.
  • lithium ions are deintercalated from the positive electrode.
  • Lithium-ion batteries are prone to gas generation under short-circuit, high temperature, overcharge and other conditions, resulting in battery expansion, and when the generated gas cannot be discharged, the battery will fail, deform, or even explode, affecting the personal safety of users.
  • the present application provides an electrochemical device and an electronic device, which can improve the safety of the electrochemical device.
  • a first aspect of the present application provides an electrochemical device, the electrochemical device comprising:
  • a housing having a cavity, and the housing includes a wall;
  • the wall surface is provided with a stress weak area.
  • the stress weak zone is a continuous structure or a discontinuous structure.
  • the total length of the stress-weak regions disposed on the same wall surface is greater than or equal to 3 mm.
  • the depth H of the stress weak zone is 30% to 90% of the thickness of the wall surface.
  • the width W of the stress weak zone is 50% to 110% of the thickness of the wall surface.
  • the wall is provided with one or more stress weak areas.
  • the wall surface is the wall surface with the largest area in the housing.
  • At least one of the inner surface and the outer surface of the wall surface is provided with the stress weak area.
  • the elastic modulus of the wall surface is greater than or equal to 1000MPa.
  • the stress weak zone includes at least one of a score, a groove, and a region with a lower strength than the material in its surrounding region.
  • the wall has an outer end, and the curvature of the stress-weak region is the same as the curvature of the outer end which is closest to the stress-weak region.
  • the wall surface has an outer end and a first area, the first area has a first outer edge, the first outer edge coincides with the outer end; the stress weak area set in the first area;
  • the ratio of the area of the first region to the area of the wall surface is 30% to 50%.
  • the outer end is offset inward by a first distance L1 to form the first region
  • the first region is an annular structure
  • the first region has a first inner edge and a first an outer edge, the first outer edge coincides with the outer end.
  • the first region is an annular structure, and the first region has a first inner edge; the first inner edge is a normal line of each point on the first outer edge or In the direction of the vertical line, the circle formed by the line segments extending to the inside of the wall by the same first distance L1.
  • the first region is an annular structure, and the first region has a first inner edge; the first inner edge is: each point on the first outer edge is along its normal line Or the vertical direction extends to the inside of the wall by the same first distance L1 to form a line segment, wherein the line segment has a non-connection point, and the two line segments adjacent to the non-connection point are further formed according to the formation of the two line segments.
  • the first outer edge of the line segment extends with the same curvature to the circle connected by the intersection.
  • both the outer end and the first inner edge are arc-shaped
  • the distance between the first inner edge and the geometric center is R1, and the radius of the outer end is R, 0.7 ⁇ R1/R ⁇ 0.8.
  • the wall surface is circular, and the first region is circular;
  • the inner diameter of the first region is R1, and the outer diameter is R;
  • the wall surface is rectangular, and the first region is a rectangular ring;
  • the wall surface is an asymmetrical shape
  • the first region is an asymmetrical ring.
  • the wall surface is L-shaped, and the first region is an L-shaped ring;
  • the first region is an asymmetric L-shaped ring.
  • the wall surface has an outer end and a second area, and the stress weak area is set in the second area; the second area has a second outer edge; the second outer edge The edge is a circle formed by the connection of line segments formed by each point on the first outer edge extending to the inside of the wall by the same third distance L3 along its normal or vertical direction.
  • the wall surface has an outer end and a second area, and the stress weak area is set in the second area; the second area has a second outer edge; the second outer edge
  • the edge is: each point on the first outer edge extends to the inside of the wall by the same third distance L3 along its normal or vertical direction to form a line segment, wherein the line segment has a non-connecting point, which is different from the non-connecting point.
  • the two adjacent line segments at the connection are further extended to the circle formed by the intersection according to the same curvature of the first outer edge forming the two line segments; the ratio of the area of the second region to the area of the wall surface 10% to 22%.
  • the wall surface has an outer end, and the outer end is offset inward by a third distance L3 to form a second outer edge, and the second outer edge encloses the second area;
  • the ratio of the area of the second region to the area of the wall surface is 10% to 22%.
  • both the outer end and the second outer edge are arc-shaped
  • the distance between the second outer edge and the geometric center is R2, and the radius of the outer end is R, 0.3 ⁇ R2/R ⁇ 0.5.
  • both the wall surface and the second area are circular;
  • both the wall surface and the second area are rectangular;
  • both the wall surface and the second region are L-shaped
  • Another aspect of the present application provides an electronic device, the electronic device comprising:
  • the electrochemical device is the electrochemical device described above.
  • the stress weak area provided on the wall surface of the electrochemical device casing is the weak part of the casing.
  • the stress weak area can form an opening, which can connect the inner cavity of the casing with the external environment where the electrochemical device is located, so as to discharge the gas in the inner cavity of the casing and reduce the internal production of the electrochemical device.
  • the risk of expansion, deformation and even explosion of the electrochemical device caused by the gas improves the safety of the electrochemical device.
  • FIG. 1 is a schematic structural diagram of a wall surface and a stress weak area provided by the application in a first specific embodiment
  • FIG. 2 is a schematic structural diagram of the wall surface and the stress weak area provided by the application in a second specific embodiment
  • FIG. 3 is a schematic diagram of the first region and the second region of the stress-weak region provided by the application in the first specific embodiment
  • FIG. 4 is a schematic diagram of the first region and the second region of the stress-weak region provided by the present application in a second specific embodiment
  • FIG. 5 is a schematic diagram of the first region and the second region of the stress-weak region provided by the present application in a third specific embodiment
  • FIG. 6 is a schematic view of the size of the stress weak area in FIG. 1 in a specific embodiment
  • FIG. 9 is a schematic diagram of the shape of the stress weak area in the third solution.
  • An embodiment of the present application provides an electrochemical device, the electrochemical device includes a casing and an electrode assembly located inside the casing, wherein the electrode assembly includes a terminal, the terminal is used for exporting electrical energy generated by the electrode assembly, and the electrode assembly At least part of the is located in the cavity of the housing for protecting the electrode assembly.
  • the shell can be in various shapes such as circle, square, L shape, irregular shape, etc.
  • the wall surface of the shell surrounds the above shapes.
  • there is a wall surface 1 whose shape is It can be in various shapes such as circle, square, L shape, irregular shape, etc. As shown in FIG. 1 and FIG. 2 , the wall surface 1 is provided with a stress weak area 2 .
  • the stress weak area 2 disposed on the wall surface 1 of the electrochemical device shell is the weak part of the shell.
  • the stress weak area 2 can form an opening, and the opening can communicate the inner cavity of the casing with the external environment where the electrochemical device is located, so as to discharge the gas in the inner cavity of the casing and reduce the electricity consumption.
  • the stress-weak region 2 in the embodiment of the present application may include at least one of a score, a groove, and a region whose strength is lower than that of the material in the surrounding region.
  • the area with lower strength than the material in the surrounding area refers to: the strength of the material in the weak stress area 2 is lower than that of other areas of the wall 1, and when the wall 1 is stressed, the material in the weak stress area 2 is easily deformed , thereby forming an opening.
  • the grooves and the nicks are areas with low strength in the wall surface 1 , that is, the areas where the openings are easily broken when subjected to force.
  • the following description takes the stress weak area 2 as a groove or a notch as an example.
  • the wall surface 1 has an outer end 11 and a first area 12 , the outer end 11 is where the outer contour of the wall surface 1 is located, and the first area 12 has a first area 12 .
  • the outer edge 122 , the first outer edge 122 coincides with the outer end portion 11 ; the stress-weak region 2 is disposed in the first region 12 , that is, the first region 12 can be used for setting the stress-weak region 2 .
  • the wall surface 1 when the pressure in the casing increases due to gas production by the electrochemical device, the wall surface 1 is subjected to the pressure, and at the position close to the outer end 11 (the first region 12 ), the pressure on the wall surface 1 is relatively large, that is, the wall surface 1 is subjected to the pressure. Positions are more prone to fracture under pressure than other positions.
  • the weak stress area 2 when the weak stress area 2 is arranged in the first area 12, compared with other positions where the weak stress area 2 is arranged on the wall surface 1, the pressure of the weak stress area 2 under the action of the gas produced in the shell is larger , that is, the stress weak area 2 at this position is easy to form an opening, and it is easier to discharge the gas in the casing, thereby further reducing the risk of expansion and deformation of the electrochemical device, or even explosion.
  • the ratio of the area of the first region 12 to the area of the wall surface 1 is 30% to 50%. In a specific embodiment, the ratio of the area of the first region 12 to the area of the wall surface 1 is 45%. In this case, the stress weak region 2 is arranged in the first region 12 to well meet the pressure relief requirements.
  • the first region 12 is an annular structure, and the first region 12 has a first inner edge 121 ; Each point along its normal or vertical direction extends to the inside of the wall surface 1 by the same first distance L1 to form a circle connected by line segments.
  • first distance L1 the first distance
  • the first inner edge 121 can also be formed in the following manner: each point on the first outer edge 122 extends a first distance toward the interior of the wall surface 1 along the direction of its normal or vertical line After L1, among the plurality of line segments formed, at least two line segments are not connected, that is, they have non-connected points (that is, the closed first outer edge 122 extends inward by the first distance L1 to form an unclosed structure), which is different from the non-connected part.
  • the two adjacent line segments at the connection are further extended to intersect, so that the first outer edge 122 extends inward by the first distance L1 to form a closed circle.
  • the extended curvature of the two line segments and the curvature of the first outer edge 122 Likewise, the closed circle is the above-mentioned first inner edge 121 .
  • the first inner edge 121 formed after extension has the same curvature and shape as the first outer edge 122 .
  • the wall surface 1 can be an asymmetrical shape, and the first region 12 is an asymmetrical ring.
  • the first area 12 when the first outer edge 122 of the first area 12 is overlapped with the outer end 11 of the wall surface 1 , the first area 12 may be an area where the outer end 11 of the wall surface 1 faces toward the outer end 11 of the wall surface 1 . Therefore, when the outer end portion 11 of the wall surface 1 is a closed structure, the first region 12 is a closed annular structure, and all parts of the first inner edge 121 are connected to the wall surface 1 The distances between the outer ends 11 of the 12 are equal, and the distance is the width of the first region 12 (the vertical distance between the first inner edge 121 and the first outer edge 122 ).
  • the stress-weak region 2 can be arranged in the annular first region 12 and between the first inner edge 121 and the first outer edge 122.
  • the stress-weak region 2 can also be arranged in the first inner edge 121 and the first outer edge 122. on an outer edge 122.
  • the second distance L2 between the outer end 11 and the geometric center of the wall surface 1 , and the first distance L1 (the distance between the first outer edge 122 and the first inner edge 121 )
  • the vertical distance) and the second distance L2 satisfy: 0.1 ⁇ L1/L2 ⁇ 0.4, for example, the ratio of the two may be 0.1, 0.2, 0.25, 0.3, 0.4, etc.
  • the ratio of the first distance L1 to the second distance L2 satisfies the above relationship
  • the ratio of the area of the first region 12 to the area of the wall surface 1 is 30% to 50%
  • the stress is weak
  • the region 2 is disposed in the first region 12 , and when gas is produced inside the electrochemical device, the stress weak region 2 can quickly form an opening to discharge the gas inside the electrochemical device, thereby improving the safety of the electrochemical device.
  • both the outer end 11 and the first inner edge 121 of the wall surface 1 may be arc-shaped, and the central angle of the outer end 11 may be 360°, or may be smaller than 360°, that is, at least part of the wall surface 1 can be arc-shaped, at this time, the distance between the first inner edge 121 and the geometric center of the wall surface 1 is R1, and the radius of the outer end 11 is R, satisfying: 0.7 ⁇ R1/R ⁇ 0.8, for example, the ratio of R1 to R may be: 0.71, 0.75, 0.8, etc.
  • R1 represents the distance between the first inner edge 121 of the first region 12 and the center of the wall surface 1 .
  • the width of the first region 12 is: R-R1, when 0.7 ⁇ R1 When /R ⁇ 0.8, 0.2R ⁇ R-R1 ⁇ 0.3R, that is, the ratio of the width of the first region 12 to the radius R of the outer end portion 11 satisfies: 0.2 ⁇ (R-R1)/R ⁇ 0.3, at this time,
  • the width of the first region 12 can satisfy the ratio of the area of the first region 12 to the area of the wall surface 1 of 30% to 50%.
  • the wall surface 1 is a circular surface, that is, the outer end 11 of the wall surface 1 is surrounded by a circular wire frame.
  • the first region 12 is a circular ring, and the first The inner diameter of the region 12 is R1 and the outer diameter is R, where,
  • the first region 12 for setting the stress weak region 2 is a regular annular structure, so as to facilitate the determination of the setting position of the stress weak region 2 .
  • the wall surface 1 is a rectangular surface, that is, the outer end 11 of the wall surface 1 is surrounded by a rectangular wire frame.
  • the first area 12 is a rectangular ring, and the wall surface 1
  • L1 can be 6mm.
  • S1/S 0.44.
  • the first region 12 for setting the stress weak region 2 is a regular rectangular structure, so as to facilitate the determination of the location of the stress weak region 2 .
  • the wall surface 1 is an L-shaped surface, that is, the outer end 11 of the wall surface 1 encloses an L-shaped wire frame, and at this time, the first area 12 is an L-shaped ring,
  • the wall surface 1 may also have a second area 13 for setting the stress weak area 2 , the second area 13 has a second outer edge 131 , and the second outer edge 131 is A closed wire frame formed by the outer contour of the second region 13 .
  • the second outer edge 131 is the same third outer edge 131 that each point on the first outer edge 122 extends to the inside of the wall surface 1 along its normal or vertical direction.
  • the second outer edge 131 can also be formed by the following method: each point on the first outer edge 122 extends a third distance L3 to the inside of the wall surface 1 along its normal or vertical direction, and then forms Among the plurality of line segments, at least two line segments are discontinuous, that is, have a non-connection (that is, the closed first outer edge 122 extends inward for a third distance L3 to form a non-closed structure), and is adjacent to the non-connection The two line segments extending further to intersect, so that the first outer edge 122 extends inward for a third distance L3 to form a closed circle.
  • the circle is the above-mentioned second outer edge 131 .
  • the outer end portion 11 of the wall surface 1 is shifted toward the interior of the wall surface 1 by a third distance L3 to form a second outer edge 131 , and the area enclosed by the second outer edge 131 is the Therefore, the second area 13 is a closed area surrounded by the second outer edge 131 . And because the second area 13 is an area formed by the outer end 11 offsetting toward the interior of the wall surface 1 , that is, the second area 13 is close to the geometric center of the wall surface 1 .
  • the wall surface 1 When the pressure in the casing increases due to gas production from the electrochemical device, the wall surface 1 is subjected to the pressure, and under the action of the pressure, the wall surface 1 is deformed to a certain extent, and the deformation of the wall surface 1 in the second region 13 is larger than that of the wall surface 1 . That is to say, this position is more likely to be broken under the action of pressure to form an opening after being subjected to pressure than other positions. Therefore, when the stress weak area 2 is set in the second area 13, the stress weak area 2 is set on the wall surface 1.
  • the deformation amount of the weak stress area 2 under the pressure of gas production in the shell is larger, that is, the weak stress area 2 at this position is easy to form an opening, and it is easier to discharge the gas in the shell, thereby further reducing the electrochemical performance. Risk of device expansion and deformation, or even explosion.
  • the ratio of the area of the second region 13 to the area of the wall surface 1 is 10% to 22%.
  • the area ratio of the two may be 10%, 15%, 20%, 22%, and the like.
  • the ratio of the area of the second area 13 to the area of the wall surface 1 may be 20%.
  • the stress weak area 2 is arranged in the second area 13 to well satisfy the pressure relief requirement. .
  • the third distance L3 is the vertical distance between the first edge 122 and the outer end 11 , at this time, the third distance L3 and the second distance L2 satisfy: 0.2 ⁇ L3/L2 ⁇ 0.5.
  • the ratio of the area of the second region 13 to the area of the wall surface 1 is 10% to 22%.
  • the stress is weak
  • the area 2 is arranged in the second area 13, and when gas is produced inside the electrochemical device, the deformation of the wall surface 1 at the position of the stress weak area 2 is relatively large, so that the stress weak area 2 can quickly form an opening so as to release the gas inside the electrochemical device. discharge to improve the safety of electrochemical devices.
  • the outer end portion 11 and the second outer edge 131 are both arc-shaped, and the central angle of the outer end portion 11 may be 360° or less than 360°, that is, At least part of the wall surface 1 may be arc-shaped.
  • the distance between the second outer edge 131 and the geometric center of the wall surface 1 is R2
  • the radius of the outer end 11 is R, 0.3 ⁇ R2/R ⁇ 0.5
  • the ratio of R2 to R may specifically be: 0.3, 0.35, 0.4, 0.45.
  • the ratio of the area of the second region 13 to the area of the wall surface 1 may be 10% to 22%.
  • the wall surface 1 is a circular surface, that is, the outer end 11 of the wall surface 1 is surrounded by a circular wire frame.
  • the second area 13 is a circular area, and the second area The radius of 13 is R2, where,
  • the second region 13 for setting the stress weak area 2 is a regular circular structure, so as to facilitate the determination of the setting position of the stress weak area 2 .
  • r in the table represents the distance between the groove and the geometric center of the wall surface 1, that is, the radius of the position where the groove is located, and r can characterize the position of the groove.
  • R2 may be 1.34mm.
  • the upper and lower limits of the battery pressure are required to be (0.1MPa, 4MPa).
  • the second area 13 for setting the stress weak area 2 is a regular rectangular structure, so as to facilitate the determination of the setting position of the stress weak area 2 .
  • D in the table represents the shortest vertical distance between the groove and the outer end 11 of the wall surface 1, and D can represent the position of the groove.
  • L3 may be 13mm.
  • the upper and lower limits of the battery pressure are required to be (0.06MPa, 2.4MPa).
  • the wall surface 1 is an L-shaped surface, that is, the outer end 11 of the wall surface 1 encloses an L-shaped wire frame.
  • the first area 12 is an L-shaped ring.
  • D in the table represents the shortest vertical distance between the groove and the outer end 11 of the wall surface 1, that is, the radius of the position where the groove is located, and D can represent the position of the groove.
  • the third distance L3 may be 7.67mm.
  • the upper and lower limits of the battery pressure are required to be (0.04MPa, 1.8MPa). It can be seen from the test results that when 5mm ⁇ D ⁇ 8.63mm, it is not within the range of the above-mentioned first area 12 and second area 13, and the groove does not open. To the effect of effective pressure relief, the average pressure relief pressure is close to or even higher than the upper limit requirement, and most of the batteries explode. When the grooves are located in the first area 12 and the second area 13 (D ⁇ 8.63mm or D ⁇ 5mm), the grooves can effectively relieve pressure and prevent the battery from exploding.
  • both the above-mentioned first region 12 and the second region 13 may be provided with a stress weak region 2 .
  • the first region 12 Both the area with the larger deformation (the second area 13) are provided with the weak stress area 2.
  • the weak stress area 2 located in the first area 12 is affected.
  • the larger stress results in fractures to form openings, and the position of the second region 13 in the wall surface 1 is deformed by a large amount, so that the stress weak region 2 at this position is fractured to form openings, and the gas inside the electrochemical device is discharged through the above two openings.
  • the shape of the stress weak area 2 can be various shapes such as circular arc, straight line, broken line, and curved shape. Taking the three schemes shown in FIGS. 7 to 9 as examples, 2 (Take the groove as an example) to verify the shape of the battery. The upper and lower pressure limits of the battery are required to be (0.1MPa, 4MPa). During the test, the location, length, width, depth and other parameters of the stress weak area are the same. The test results The following table:
  • the curvature of the stress-weak region 2 is the same as the curvature of the outer end portion 11 closest to the stress-weak region 2 .
  • the shape of the stress-weak area 2 is arc-shaped as shown in FIG. 9 .
  • the shape of the stress-weak area 2 is linear.
  • the shape of the stress-weak region 2 is a zigzag shape, so the curvature of the stress-weak region 2 and the curvature of the outer end portion 11 closest to the stress-weak region 2 may be the same.
  • the stress weak zone 2 may be a continuous structure or a discontinuous structure. As shown in FIG. 1 and FIG. 2 , the stress-weak region 2 is a discontinuous structure, that is, a plurality of spaced-distributed breakpoints form the stress-weak region 2 .
  • the wall surface 1 may be provided with one or more stress-weak regions 2, and each stress-weak region 2 may be a continuous structure or a discontinuous structure.
  • the total length of the stress-weak regions 2 disposed on the same wall 1 is greater than or equal to 3 mm.
  • the total length is the length of the stress-weak regions 2.
  • the total length is the sum of the lengths of the discontinuous structures. When there are multiple stress weak areas 2 on the wall 1, the total length is The sum of the lengths of the strip stress weak zone 2.
  • the strength of the wall 1 will be low, resulting in a low structural strength of the battery and reducing the service life of the battery; if the stress on the same wall 1 If the total length of the weak area 2 is too small, when the pressure inside the battery is too high due to gas production, the area of the opening formed by the rupture of the weak area 2 is small, and it takes a long time for the gas inside the battery to be discharged, and the pressure cannot be released quickly. , resulting in lower battery safety.
  • the total length of the stress-weak regions 2 on the same wall 1 is greater than or equal to 3 mm, the casing of the battery has high strength and service life. At the same time, the opening area formed by the rupture of the stress-weak regions 2 It can quickly discharge the gas inside the battery, thereby reducing the risk of battery expansion and deformation, or even explosion, and improving the safety of the battery.
  • a verification test is carried out on the total length of the stress weak area 2.
  • the upper and lower pressure limits of the battery are required to be (0.1MPa, 4MPa), and the location of the stress weak area during the test is set. , shape, width, depth and other parameters are the same, the test results are as follows:
  • the depth H of the stress-weak region 2 is 30% to 90% of the thickness of the wall surface 1.
  • the ratio of the depth of the stress-weak region 2 to the thickness of the wall surface 1 may be : 30%, 50%, 60%, 80%, 90%, etc.
  • the depth H of the stress-weak region 2 is too large (for example, greater than 90% of the thickness of the wall surface 1), when the battery does not produce gas during normal operation, the structural strength of the casing at the stress-weak region 2 is low and is easily damaged. It will lead to battery failure, reduce the service life of the battery, and there is a risk of liquid leakage from the position of the stress weak area 2; , the pressure required for the fracture of the stress weak region 2 at the depth H is relatively large, that is, only when the pressure inside the battery reaches a large value, the stress weak region 2 can form an opening, resulting in that the gas inside the battery cannot be quickly discharged.
  • the weak stress region 2 when the depth H of the weak stress region 2 is 30% to 90% of the thickness of the wall surface 1, and the battery is working normally, the weak stress region 2 will not significantly reduce the structural strength of the casing, thereby reducing the risk of battery damage.
  • the stress weak area 2 of this depth can be quickly broken to form an opening when gas is generated inside the battery, so that the gas inside the battery can be quickly discharged, thereby reducing the risk of battery expansion and deformation, or even explosion, and improving the battery life. safety.
  • a verification test is carried out on the depth H of the stress weak area 2.
  • the upper and lower pressure limits of the battery are required to be (0.1MPa, 4MPa), and the setting position of the stress weak area during the test. , shape, length, width and other parameters are the same, the test results are as follows:
  • the width W of the stress weak area 2 is 50% to 110% of the thickness of the wall surface 1 .
  • the ratio of the width W of the stress weak region 2 to the thickness of the wall surface 1 may be: 50%, 60%, 90%, 100%, 110%, and so on. It can be understood that, the larger the width W of the stress-weak region 2 is, the larger the area of the stress-weak region 2 is.
  • the width W of the weak stress region 2 is too large (for example, greater than 110% of the thickness of the wall surface 1), the area of the wall surface 1 occupied by the weak stress region 2 is relatively large.
  • the structural strength at the position of the weak stress area 2 is low and easy to be damaged, which leads to battery failure and reduces the service life of the battery;
  • the width W of the weak stress area 2 is too small (for example, less than 50% of the thickness of the wall 1), the weak area of stress The area of the wall surface 1 occupied by 2 is too small.
  • the opening formed by the fracture of the weak stress region 2 is too small, so that the gas inside the battery cannot be quickly discharged.
  • the weak stress region 2 when the width W of the weak stress region 2 is 50% to 110% of the thickness of the wall surface 1, and the battery is working normally, the weak stress region 2 will not significantly reduce the structural strength of the casing, thereby reducing the damage to the battery.
  • the stress weak area 2 of this width W has a large opening when gas is generated inside the battery, which can quickly discharge the gas inside the battery, thereby reducing the risk of battery expansion and deformation, or even explosion, and improving the battery security.
  • a verification test is performed on the width W of the stress weak area 2.
  • the upper and lower pressure limits of the battery are required to be (0.1MPa, 4MPa), and the setting position of the stress weak area during the test. , shape, length, depth and other parameters are the same, the test results are as follows:
  • the wall surface 1 is the wall surface with the largest area in the housing, or the wall surface with the second largest area, that is to say, the stress weak area 2 in the embodiment of the present application is set on the wall surface with the larger area in the housing , the area of the wall surface is larger, so that there is a larger space for setting the stress weak area 2 .
  • the stress-weak region 2 may be disposed on at least one of the inner surface and the outer surface of the wall surface 1 , and parameters such as the position, size and shape of the stress-weak region 2 are defined by the foregoing embodiments.
  • the elastic modulus of the wall surface 1 is greater than or equal to 1000Mpa, that is, the stress weak area 2 is set on the wall surface with higher hardness, and the wall surface 1 with this hardness is not easily elastically deformed under the action of pressure, so that the shell is not easily deformed. Under the action of the pressure of the internal gas production, the stress weak area 2 is fractured to generate an opening, so that the gas inside the shell is discharged.
  • the material of the wall surface 1 may include one or more of PC material, aluminum-plastic film, and metal.
  • the processing method of the weak stress region 2 may be laser cutting, which has the advantages of high processing accuracy, high efficiency, and little damage to other parts of the casing.
  • the electrochemical device of the present application includes any device in which an electrochemical reaction occurs, and specific examples thereof include all kinds of primary batteries, secondary batteries, fuel cells, solar cells, or capacitors.
  • the electrochemical device is a lithium secondary battery, including a lithium metal secondary battery, a lithium ion secondary battery, a lithium polymer secondary battery, or a lithium ion polymer secondary battery.
  • the electrochemical devices in the embodiments of the present application can be used in various fields, and as long as the devices that can be powered by the electrochemical devices can be used, the electrochemical devices in the embodiments of the present application can be used.
  • the electrochemical device can be used in components such as electrochemical device packages for electric vehicles and electronic devices, and the electronic devices can be mobile phones, tablet computers, desktop computers, laptop computers, handheld computers, notebook computers, and ultra-mobile personal computers.
  • UMPC ultra-mobile personal computer
  • PDA personal digital assistants
  • AR augmented reality
  • VR virtual reality
  • AI artificial intelligence
  • wearable devices wearable devices
  • vehicle-mounted devices smart home devices
  • smart city devices smart city devices
  • specific types of the electronic devices are not particularly limited in this embodiment of the present application.
  • the electronic device may include components such as a casing, a screen, a circuit board, and an electrochemical device, wherein the screen, the circuit board, and the electrochemical device are all mounted on the casing, and the electrochemical device is described in any of the above embodiments.
  • Electrochemical device may include components such as a casing, a screen, a circuit board, and an electrochemical device, wherein the screen, the circuit board, and the electrochemical device are all mounted on the casing, and the electrochemical device is described in any of the above embodiments. Electrochemical device.

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Abstract

本申请涉及一种电化学装置及电子设备，所述电化学装置包括：壳体，具有腔体，且所述壳体包括壁面；其中，所述壁面设置有应力薄弱区。本申请中，设置于电化学装置壳体壁面的应力薄弱区为该壳体的薄弱部，当电化学装置在短路、高温、过充等条件下产生气体时，壳体内部的压力增大，在该压力作用下，应力薄弱区能够形成开口，该开口能够将壳体的内腔与电化学装置所处的外部环境连通，从而将壳体内腔内的气体排出，降低电化学装置内部产气导致的电化学装置膨胀变形、甚至爆炸的风险，提高电化学装置的安全性。

Description

一种电化学装置及电子设备 技术领域
本申请涉及储能器件技术领域，尤其涉及一种电化学装置及电子设备。
背景技术
锂离子电池是一种可充电的二次电池，工作时，锂离子在正极和负极之间移动，并嵌入电极或从电极上脱嵌来产生电能，具体地，充电时，锂离子从正极脱嵌，经过电解质嵌入负极，放电时，锂离子从负极脱嵌，经过电解质嵌入正极。锂离子电池在短路、高温、过充等条件下容易产生气体，导致电池膨胀，且产生的气体无法排出时会导致电池故障变形，甚至爆炸，影响用户的人身安全。
申请内容
本申请提供了一种电化学装置及电子设备，能够提高电化学装置的安全性。
本申请第一方面提供一种电化学装置，所述电化学装置包括：
壳体，具有腔体，且所述壳体包括壁面；
其中，所述壁面设置有应力薄弱区。
在一种可能的设计中，所述应力薄弱区为连续结构或非连续结构。
在一种可能的设计中，设置于同一所述壁面的所述应力薄弱区的总长度大于或等于3mm。
在一种可能的设计中，所述应力薄弱区的深度H为所述壁面的厚度的30％～90％。
在一种可能的设计中，所述应力薄弱区的宽度W为所述壁面的厚度的 50％～110％。
在一种可能的设计中，所述壁面设置有一个或多个应力薄弱区。
在一种可能的设计中，所述壁面为所述壳体中面积最大的壁面。
在一种可能的设计中，所述壁面的内表面、外表面中的至少一者设置有所述应力薄弱区。
在一种可能的设计中，所述壁面的弹性模量大于或等于1000MPa。
在一种可能的设计中，所述应力薄弱区包括刻痕、凹槽、强度低于其周围区域材料的区域中的至少一种。
在一种可能的设计中，所述壁面具有外端部，所述应力薄弱区的曲率和与所述应力薄弱区距离最近的所述外端部的曲率相同。
在一种可能的设计中，所述壁面具有外端部和第一区域，所述第一区域具有第一外边缘，所述第一外边缘与所述外端部重合；所述应力薄弱区设置于所述第一区域；
所述第一区域的面积与所述壁面的面积之比为30％～50％。
在一种可能的设计中，所述外端部向内偏移第一距离L1形成所述第一区域，所述第一区域为环形结构，所述第一区域具有第一内边缘和第一外边缘，所述第一外边缘与所述外端部重合。
在一种可能的设计中，所述第一区域为环形结构，所述第一区域具有第一内边缘；所述第一内边缘为所述第一外边缘上的各点沿其法线或垂线方向，向所述壁面内部延伸相同的第一距离L1形成的线段所连接成的圈。
在一种可能的设计中，所述第一区域为环形结构，所述第一区域具有第一内边缘；所述第一内边缘为：所述第一外边缘上的各点沿其法线或垂线方向向所述壁面内部延伸相同的第一距离L1形成线段，其中，所述线段具有非连接处，与所述非连接处相邻的两条所述线段进一步根据形成所述两条线段的第一外边缘相同曲率进行延伸至相交所连接成的圈。
在一种可能的设计中，所述外端部与所述壁面的几何中心之间具有第二距离L2，所述第一距离L1与所述第二距离L2满足：0.1≤L1/L2≤0.4。
在一种可能的设计中，所述外端部和所述第一内边缘均为圆弧形；
所述第一内边缘与所述几何中心之间的距离为R1，所述外端部的半径为R，0.7≤R1/R≤0.8。
在一种可能的设计中，所述壁面为圆形，所述第一区域为圆环形；
所述第一区域的内径为R1，外径为R；
其中，
Figure PCTCN2020108396-appb-000001
在一种可能的设计中，所述壁面为矩形，所述第一区域为矩形环；
所述壁面的边长分别为t1、t2时，所述第一距离L1、t1、t2满足关系(t1-2L1)×(t2-2L1)＝0.55t1×t2。
在一种可能的设计中，所述壁面为不对称形状，所述第一区域为不对称环。
在一种可能的设计中，所述壁面为L形，所述第一区域为L形环；
所述壁面的各边长分别为t1、t2、t3、t4、t5、t6，当t2＝t4+t6、t3＝t1+t5时，所述第一距离L1、t1、t2、t3、t4、t5、t6满足关系：0.45×(t2×t3-t5×t6)＝(t2×t3-(t2-2L1)×(t3-2L1))。
在一种可能的设计中，所述第一区域为不对称L形环。
在一种可能的设计中，所述壁面具有外端部和第二区域，且所述应力薄弱区设置于所述第二区域；所述第二区域具有第二外边缘；所述第二外边缘为所述第一外边缘上的各点沿其法线或垂线方向，向所述壁面内部延伸相同的第三距离L3形成的线段所连接成的圈。
在一种可能的设计中，所述壁面具有外端部和第二区域，且所述应力薄弱区设置于所述第二区域；所述第二区域具有第二外边缘；所述第二外边缘为：所述第一外边缘上的各点沿其法线或垂线方向向所述壁面内部延伸相同 的第三距离L3形成线段，其中，所述线段具有非连接处，与所述非连接处相邻的两条所述线段进一步根据形成所述两条线段的第一外边缘相同曲率进行延伸至相交所连接成的圈；所述第二区域的面积与所述壁面的面积之比为10％～22％。
在一种可能的设计中，所述壁面具有外端部，所述外端部向内偏移第三距离L3形成第二外边缘，所述第二外边缘围成第二区域；
所述第二区域的面积与所述壁面的面积之比为10％～22％。
在一种可能的设计中，所述外端部与所述壁面的几何中心之间具有第二距离L2，所述第三距离L3与所述第二距离L2满足：0.2≤L3/L2≤0.5。
在一种可能的设计中，所述外端部和所述第二外边缘均为圆弧形；
所述第二外边缘与所述几何中心之间的距离为R2，所述外端部的半径为R，0.3≤R2/R≤0.5。
在一种可能的设计中，所述壁面和所述第二区域均为圆形；
其中，
Figure PCTCN2020108396-appb-000002
在一种可能的设计中，所述壁面和所述第二区域均为矩形；
所述壁面的边长分别为t1、t2时，所述第三距离L3、t1、t2满足关系(t1-2L3)×(t2-2L3)＝0.2t1×t2。
在一种可能的设计中，所述壁面和所述第二区域均为L形；
所述壁面的各边长分别为t1、t2、t3、t4、t5、t6，且t2＝t4+t6、t3＝t1+t5时，所述第三距离L3、t1、t2、t3、t4、t5、t6满足关系：(t3-2L3)×(t4-2L3)+t6×(t1-2L3)＝0.2×(t2×t3-t5×t6)。
本申请另一方面提供一种电子设备，所述电子设备包括：
外壳；
屏幕，安装于所述外壳；
电化学装置，位于所述外壳的内腔；
其中，所述电化学装置为以上所述的电化学装置。
本申请中，设置于电化学装置壳体的壁面的应力薄弱区为该壳体的薄弱部，当电化学装置在短路、高温、过充等条件下产生气体时，壳体内部的压力增大，在该压力作用下，应力薄弱区能够形成开口，该开口能够将壳体的内腔与电化学装置所处的外部环境连通，从而将壳体内腔内的气体排出，降低电化学装置内部产气导致的电化学装置膨胀变形、甚至爆炸的风险，提高电化学装置的安全性。
应当理解的是，以上的一般描述和后文的细节描述仅是示例性的，并不能限制本申请。
附图说明
图1为本申请所提供壁面和应力薄弱区在第一种具体实施例中的结构示意图；
图2为本申请所提供壁面和应力薄弱区在第二种具体实施例中的结构示意图；
图3为本申请所提供应力薄弱区的第一区域和第二区域在第一种具体实施例中的示意图；
图4为本申请所提供应力薄弱区的第一区域和第二区域在第二种具体实施例中的示意图；
图5为本申请所提供应力薄弱区的第一区域和第二区域在第三种具体实施例中的示意图；
图6为图1中的应力薄弱区在一种具体实施例中的尺寸示意图；
图7为应力薄弱区在第一种方案中的形状示意图；
图8为应力薄弱区在第二种方案中的形状示意图；
图9为应力薄弱区在第三种方案中的形状示意图。
附图标记：
1-壁面；
11-外端部；
12-第一区域；
121-第一内边缘；
122-第一外边缘；
13-第二区域；
131-第二外边缘；
2-应力薄弱区。
此处的附图被并入说明书中并构成本说明书的一部分，示出了符合本申请的实施例，并与说明书一起用于解释本申请的原理。
具体实施方式
为了更好的理解本申请的技术方案，下面结合附图对本申请实施例进行详细描述。
应当明确，所描述的实施例仅仅是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员所获得的所有其它实施例，都属于本申请保护的范围。
在本申请实施例中使用的术语是仅仅出于描述特定实施例的目的，而非旨在限制本申请。在本申请实施例和所附权利要求书中所使用的单数形式的“一种”、“所述”和“该”也旨在包括多数形式，除非上下文清楚地表示其他含义。
应当理解，本文中使用的术语“和/或”仅仅是一种描述关联对象的关联关系，表示可以存在三种关系，例如，A和/或B，可以表示：单独存在A，同时存在A和B，单独存在B这三种情况。另外，本文中字符“/”，一般表示前 后关联对象是一种“或”的关系。
需要注意的是，本申请实施例所描述的“上”、“下”、“左”、“右”等方位词是以附图所示的角度来进行描述的，不应理解为对本申请实施例的限定。此外，在上下文中，还需要理解的是，当提到一个元件连接在另一个元件“上”或者“下”时，其不仅能够直接连接在另一个元件“上”或者“下”，也可以通过中间元件间接连接在另一个元件“上”或者“下”。
本申请实施例提供一种电化学装置，该电化学装置包括壳体和位于壳体内部的电极组件，其中，该电极组件包括端子，该端子用于将电极组件产生的电能导出，该电极组件的至少部分位于壳体的腔体内，该壳体用于保护电极组件。其中，壳体可以为圆形、方形、L形、不规则形等多种形状，壳体的壁面围成上述各形状，该壳体的多个壁面中，具有壁面1，该壁面1的形状可以为圆形、方形、L形、不规则形等多种形状，如图1和图2所示，该壁面1设置有应力薄弱区2。
本实施例中，设置于电化学装置壳体的壁面1的应力薄弱区2为该壳体的薄弱部，当电化学装置在短路、高温、过充等条件下产生气体时，壳体内部的压力增大，在该压力作用下，应力薄弱区2能够形成开口，该开口能够将壳体的内腔与电化学装置所处的外部环境连通，从而将壳体内腔内的气体排出，降低电化学装置内部产气导致的电化学装置膨胀变形、甚至爆炸的风险，提高电化学装置的安全性。
具体地，本申请实施例中的应力薄弱区2可以包括刻痕、凹槽、强度低于其周围区域材料的区域中的至少一种。其中，强度低于其周围区域材料的区域指的是：该应力薄弱区2的材料的强度低于该壁面1的其他区域的强度，当壁面1受力时，应力薄弱区2的材料容易变形，从而形成开口。同时，凹槽和刻痕均为该壁面1中强度较低的区域，即受力时容易断裂开口的区域。以下以应力薄弱区2为凹槽或刻痕为例描述。
具体地，如图3～5所示，该壁面1具有外端部11和第一区域12，该外端部 11为该壁面1的外轮廓所在的位置，所述第一区域12具有第一外边缘122，所述第一外边缘122与所述外端部11重合；应力薄弱区2设置于第一区域12，即该第一区域12为可以用于设置应力薄弱区2的区域。
本实施例中，电化学装置产气导致壳体内的压力增大时，该壁面1受到该压力，且靠近外端部11的位置(第一区域12)，壁面1的压强较大，即该位置相较于其他位置更加容易在压强的作用下断裂。因此，将应力薄弱区2设置于该第一区域12时，与应力薄弱区2设置于壁面1的其他位置相比，应力薄弱区2在壳体内产气的压力作用下所受到的压强较大，即该位置的应力薄弱区2容易形成开口，更加容易将壳体内的气体排出，从而进一步降低电化学装置膨胀变形、甚至爆炸的风险。
另外，该第一区域12的面积与壁面1的面积之比为30％～50％，例如，二者的面积之比可以为30％、35％、38％、45％、50％等。在一种具体实施例中，该第一区域12的面积与壁面1的面积之比为45％，此时，该第一区域12内设置该应力薄弱区2能够很好的满足泄压要求。
更具体地，如图3～4所示，该第一区域12为环形结构，该第一区域12具有第一内边缘121；所述第一内边缘121为所述第一外边缘122上的各点沿其法线或垂线方向，向所述壁面1内部延伸相同的第一距离L1形成的线段所连接成的圈。或者，如图5所示，该第一内边缘121还可以通过下述方式形成：该第一外边缘122上的各点沿其法线或垂线的方向向壁面1的内部延伸第一距离L1后，形成的多条线段中，至少两条线段不连接，即具有非连接处(即该封闭的第一外边缘122向内延伸第一距离L1后形成不封闭的结构)，与该非连接处相邻的两条线段进一步延伸从而相交，使得第一外边缘122向内延伸第一距离L1后形成封闭的圈，此时，两条线段延伸后的曲率与第一外边缘122的曲率相同，该封闭的圈即为上述第一内边缘121。
因此，如图5所示，延伸后形成的第一内边缘121的曲率和形状与第一外边缘122相同。
在一些实施例中，所述壁面1可为不对称形状，所述第一区域12为不对称环。
本实施例中，如图3～5所示，当第一区域12的第一外边缘122与壁面1的外端部11重合时，该第一区域12可以为壁面1的外端部11向内偏移第一距离L1形成的环形结构，因此，当壁面1的外端部11为封闭形结构时，该第一区域12为封闭环形结构，且第一内边缘121的各处与壁面1的外端部11之间的距离相等，该距离为第一区域12的宽度(第一内边缘121与第一外边缘122之间的垂直距离)。应力薄弱区2可以设置于该环形的第一区域12内，并位于第一内边缘121与第一外边缘122之间，当然，该应力薄弱区2也可以设置于第一内边缘121和第一外边缘122上。
进一步地，如图3～5所示，该外端部11与壁面1的几何中心之间具有第二距离L2，上述第一距离L1(第一外边缘122与第一内边缘121之间的垂直距离)与该第二距离L2满足：0.1≤L1/L2≤0.4，例如，二者的比例可以为0.1、0.2、0.25、0.3、0.4等。
本实施例中，当第一距离L1与第二距离L2的比值满足上述关系时，使得该第一区域12的面积与壁面1的面积之比为30％～50％，此时，该应力薄弱区2设置于该第一区域12，且电化学装置内部产气时，应力薄弱区2能够快速形成开口从而将电化学装置内部的气体排出，提高电化学装置的安全性。
在一种具体实施例中，如图3所示，壁面1的外端部11和第一内边缘121均可以为圆弧形，该外端部11的圆心角可以为360°，也可以小于360°，即该壁面1的至少部分可以为圆弧形，此时，第一内边缘121与壁面1的几何中心之间的距离为R1，外端部11的半径为R，满足：0.7≤R1/R≤0.8，例如，R1与R之比可以为：0.71、0.75、0.8等。
本实施例中，如图3所示，R1表示第一区域12的第一内边缘121距离壁面1的中心的距离，此时，第一区域12的宽度为：R-R1，当0.7≤R1/R≤0.8时，0.2R≤R-R1≤0.3R，即第一区域12的宽度与外端部11的半径R之比满足：0.2 ≤(R-R1)/R≤0.3，此时，该宽度的第一区域12能够满足第一区域12的面积与壁面1的面积之比为30％～50％。
具体地，如图3所示，该壁面1为圆形面，即该壁面1的外端部11围成圆形线框，此时，该第一区域12为圆环形，且该第一区域12的内径为R1，外径为R，其中，
Figure PCTCN2020108396-appb-000003
本实施例中，第一区域12的面积S1＝πR 2-πR1 2＝0.45πR 2，此时，第一区域12的面积S1与壁面1的面积S之比满足：S1/S＝0.45。
本实施例中，当壁面1为规则的圆形面时，用于设置应力薄弱区2的第一区域12为规则的圆环形结构，从而便于判定应力薄弱区2的设置位置。
例如，当R＝3mm时，R1可以为2.22mm，此时，第一区域12的内径为R1＝2.22mm，外径为R＝3mm，S1/S＝0.4524。
在另一种具体实施例中，如图4所示，壁面1为矩形面，即该壁面1的外端部11围成矩形线框，此时，第一区域12为矩形环，且壁面1的边长分别为t1、t2(矩形线框的长度和宽度)时，上述第一距离L1、t1、t2满足关系(t1-2L1)×(t2-2L1)＝0.55t1×t2。
本实施例中，壁面1的面积S满足：S＝t1×t2，第一区域12的面积S1满足:S1＝S-(t1-2L1)×(t2-2L1)＝0.45t1×t2，因此，第一区域12的面积与壁面1的面积之比满足S1/S＝0.45。
例如，当t1＝60mm，t2＝40mm时，L1可以为6mm，此时，第一区域12的面积为S1＝1056mm 2，壁面1的面积为S＝2400mm 2，S1/S＝0.44。
本实施例中，当壁面1为规则的矩形面时，用于设置应力薄弱区2的第一区域12为规则的矩形结构，从而便于判定应力薄弱区2的设置位置。
在又一种具体实施例中，如图5所示，壁面1为L形面，即该壁面1的外端部11围成L形线框，此时，第一区域12为L形环，当壁面1的各边长分别为t1、t2、t3、t4、t5、t6，且当t2＝t4+t6、t3＝t1+t5时，第一距离L1、t1、t2、t3、t4、t5、t6满足关系：0.45×(t2×t3-t5×t6)＝(t2×t3-(t2-2L1)×(t3-2L1))。
本实施例中，壁面1的面积S满足：S＝t2×t3-t5×t6，第一区域12的面积S1满足：S1＝t2×t3-(t2-2L1)(t3-2L1)，因此，第一区域12的面积与壁面1的面积之比满足S1/S＝0.45。
例如，t1＝25mm、t2＝60mm、t3＝50mm、t4＝20mm、t5＝25mm、t6＝40mm时，第一距离L1可以为4.32mm，此时，第一区域12的面积为S1＝875.75mm 2，壁面1的面积为S＝2000mm 2，S1/S＝0.438。
另一方面，如图3～5所示，该壁面1还可以具有用于设置应力薄弱区2的第二区域13，该第二区域13具有第二外边缘131，该第二外边缘131为第二区域13的外轮廓形成的封闭线框。
具体地，如图3～4所示，所述第二外边缘131为所述第一外边缘122上的各点沿其法线或垂线方向，向所述壁面1内部延伸相同的第三距离L3形成的线段所连接成的圈。或者，如图5所示，该第二外边缘131还可以通过下述方式形成：第一外边缘122上的各点沿其法线或垂线方向向壁面1内部延伸第三距离L3后形成的多条线段中，至少两条线段不连续，即具有非连接处(即该封闭的第一外边缘122向内延伸第三距离L3后形成不封闭的结构)，与该非连接处相邻的两条线段进一步延伸从而相交，使得第一外边缘122向内延伸第三距离L3后形成封闭的圈，此时，两条线段延伸后的曲率与第一外边缘122的曲率相同，该封闭的圈即为上述第二外边缘131。
本实施例中，如图3～5所示，壁面1的外端部11朝向壁面1的内部偏移第三 距离L3后形成第二外边缘131，该第二外边缘131围成的区域即为该第二区域13，因此，该第二区域13为由第二外边缘131围成的封闭形区域。且由于该第二区域13为外端部11朝向壁面1的内部偏移形成的区域，即该第二区域13靠近壁面1的几何中心。
当电化学装置产气导致壳体内的压力增大时，该壁面1受到该压力，在该压力作用下，壁面1发生一定程度的变形，且该第二区域13内的壁面1的变形量较大，即该位置受压力后相较于其他位置更加容易在压强的作用下断裂形成开口，因此，将应力薄弱区2设置于该第二区域13时，与应力薄弱区2设置于壁面1的其他位置相比，应力薄弱区2在壳体内产气的压力作用下的变形量较大，即该位置的应力薄弱区2容易形成开口，更加容易将壳体内的气体排出，从而进一步降低电化学装置膨胀变形、甚至爆炸的风险。
另外，该第二区域13的面积与壁面1的面积之比为10％～22％。例如，二者的面积之比可以为10％、15％、20％、22％等。在一种具体实施例中，该第二区域13的面积与壁面1的面积之比可以为20％，此时，该第二区域13内设置该应力薄弱区2能够很好的满足泄压要求。
具体地，如图3～5所示，该外端部11与壁面1的几何中心之间具有第二距离L2，上述第三距离L3为第一边缘122与外端部11之间的垂直距离，此时，第三距离L3与第二距离L2满足：0.2≤L3/L2≤0.5。
本实施例中，当第三距离L3与第二距离L2的比值满足上述关系时，使得该第二区域13的面积与壁面1的面积之比为10％～22％，此时，该应力薄弱区2设置于该第二区域13，且电化学装置内部产气时，应力薄弱区2所在位置的壁面1变形量较大，使得应力薄弱区2能够快速形成开口从而将电化学装置内部的气体排出，提高电化学装置的安全性。
在一种具体实施例中，如图3所示，外端部11和第二外边缘131均为圆弧形，该外端部11的圆心角可以为360°，也可以小于360°，即该壁面1的至少部分可以为圆弧形，此时，第二外边缘131与壁面1的几何中心之间的距离为 R2，外端部11的半径为R，0.3≤R2/R≤0.5，例如，R2与R之比具体可以为：0.3、0.35、0.4、0.45。
本实施例中，当0.3≤R2/R≤0.5时，第二区域13的面积与壁面1的面积之比可以为10％～22％。
具体地，如图3所示，该壁面1为圆形面，即该壁面1的外端部11围成圆形线框，此时，第二区域13为圆形区域，且该第二区域13的半径为R2，其中，
Figure PCTCN2020108396-appb-000004
本实施例中，第二区域13的面积S2＝πR2 2＝0.2πR 2，此时，第二区域13的面积S2与壁面1的面积S之比满足S2/S＝0.2。
本实施例中，当壁面1为规则的圆形面时，用于设置应力薄弱区2的第二区域13为规则的圆形结构，从而便于判定应力薄弱区2的设置位置。
为了验证壁面1设置应力薄弱区2(以凹槽为例)后的泄压效果，进行泄压对比试验，其中，应力薄弱区2设置为如图3所示的实施例，且实验过程中壳体的形状、厚度、材料等参数均相同，区别仅在于是否设置应力薄弱区2以及应力薄弱区2的设置位置不同。实验结果如下表：
r/mm r2/R2 试验数量 平均泄压压强/MPa 爆炸数量
2.6 0.751 10 0.37 0
2.4 0.64 10 1.62 0
2.22 0.5476 10 2.5 0
2.12 0.50 10 3.77 1
1.9 0.40 10 3.85 3
1.6 0.284 10 4.25 6
1.34 0.200 10 3.29 1
0.7 0.054 10 2.71 0
0 0 10 0.89 0
无凹槽 / 10 6.2 10
其中，该表中的r表示凹槽与壁面1的几何中心之间的距离，即凹槽所在位置的半径，r能够表征凹槽的位置。例如，当R＝3mm时，R2可以为1.34mm。 试验中r＝2.12mm时凹槽位于第一区域12的第一外边缘121，r＝1.34mm时凹槽位于第二区域13的第二外边缘131。该电池压强上下限要求为(0.1MPa，4MPa)，从试验结果可以看出，当r＝1.6时，即凹槽不在上述第一区域12和第二区域13的范围内，凹槽未起到有效泄压的作用，平均泄压压强高于上限要求，大部分电池发生爆炸。而当凹槽位于第一区域12和第二区域13内(r≥2.12mm或r≤1.34mm)时，该凹槽2能够有效泄压，防止电池发生爆炸。进一步地，当凹槽位于第一区域12的面积S1与壁面1的面积S之比为45％的区域内时(即r≥2.22mm)，平均泄压压强进一步降低，没有电池发生爆炸。
在另一种具体实施例中，壁面1为矩形面，即该壁面1的外端部11围成矩形线框，此时，第一区域12为矩形环，且壁面1的边长分别为t1、t2(矩形线框的长度和宽度)时，上述第一距离L1、t1、t2满足关系S1＝t1×t2-(t1-2L1)×(t2-2L1)＝0.5t1×t2。
本实施例中，壁面1的面积S满足：S＝t1×t2，第二区域13的面积S2满足：S2＝(t1-2L1)×(t2-2L1)＝0.2t1×t2，因此，第二区域13的面积S2与壁面1的面积之比满足S2/S＝0.2。
本实施例中，如图4所示，当壁面1为规则的矩形面时，用于设置应力薄弱区2的第二区域13为规则的矩形结构，从而便于判定应力薄弱区2的设置位置。
为了验证壁面1设置应力薄弱区2(以凹槽为例)后的泄压效果，进行泄压对比试验，其中，应力薄弱区2设置为如图4所示的实施例，且实验过程中壳体的形状、厚度、材料等参数均相同，区别仅在于是否设置应力薄弱区2以及应力薄弱区2的设置位置不同。实验结果如下表：
Figure PCTCN2020108396-appb-000005
Figure PCTCN2020108396-appb-000006
其中，该表中的D表示凹槽与壁面1外端部11的最短垂直距离，D能够表征凹槽的位置。例如，当t1＝60mm，t2＝40mm时，L3可以为13mm。试验中D＝6mm时，凹槽位于上述第一区域12的第一内边缘121，D＝13mm时，凹槽位于上述第二区域13的第二外边缘131。该电池压强上下限要求为(0.06MPa，2.4MPa)，从试验结果可以看出，当8mm≤D<13mm时，不在上述第一区域12和第二区域13的范围内，凹槽未起到有效泄压的作用，平均泄压压强接近甚至高于上限要求，大部分电池发生爆炸。而当凹槽位于第一区域12和第二区域13内(D≥13mm或D<8mm)时，该凹槽能够有效泄压，防止电池发生爆炸。
在又一种具体实施例中，如图5所示，壁面1为L形面，即该壁面1的外端部11围成L形线框，此时，第一区域12均L形环，当壁面1的各边长分别为t1、t2、t3、t4、t5、t6，且t2＝t4+t6、t3＝t1+t5时，上述第三距离L1、t1、t2、t3、t4、t5、t6满足关系：0.45×(t2×t3-t5×t6)＝(t2×t3-(t2-2L1)×(t3-2L1))。
本实施例中，壁面1的面积S满足：S＝t2×t3-t5×t6，第二区域13的面积S2满足：S2＝(t3-2L3)×(t4-2L3)+t6×(t1-2L3)，因此，第二区域13的面积与壁面1的面积之比满足S2/S＝0.2。
为了验证壁面1设置应力薄弱区2(以凹槽为例)后的泄压效果，进行泄压对比试验，其中，应力薄弱区2设置为如图5所示的实施例，且实验过程中 壳体的形状、厚度、材料等参数均相同，区别仅在于是否设置应力薄弱区2以及应力薄弱区2的设置位置不同。实验结果如下表：
D/mm (t2×t3-(t2-2D)×(t3-2D))/(t2×t3-t5×t6) 试验数量 平均泄压压强/MPa 爆炸数量
1 0.108 10 0.16 0
2 0.212 10 0.41 0
3 0.312 10 1.07 0
3.75 0.384 10 1.44 0
4.32 0.438 10 1.65 1
5 0.5 10 1.77 3
6 0.588 10 3.2 8
7 0.672 10 2.06 5
7.67 0.726 10 1.76 4
8.63 0.8 10 1.71 1
9 0.828 10 1.4 0
10 0.9 10 0.68 0
无凹槽 / 10 3.1 10
其中，该表中的D表示凹槽与壁面1外端部11的最短垂直距离，即凹槽所在位置的半径，D能够表征凹槽的位置。例如，t1＝25mm、t2＝60mm、t3＝50mm、t4＝20mm、t5＝25mm、t6＝40mm时，第三距离L3可以为7.67mm。试验中D＝5mm时，凹槽位于上述第一区域12的第一内边缘121，D＝8.63mm时，凹槽位于上述第二区域13的第二外边缘131。该电池压强上下限要求为(0.04MPa，1.8MPa)，从试验结果可以看出，当5mm<D<8.63mm时，不在上述第一区域12和第二区域13的范围内，凹槽未起到有效泄压的作用，平均泄压压强接近甚至高于上限要求，大部分电池发生爆炸。而当凹槽位于第一区域12和第二区域13内(D≥8.63mm或D≤5mm)时，该凹槽能够有效泄压，防止电池发生爆炸。
在一种具体实施例中，如图3～5所示，上述第一区域12和第二区域13均可以设置有应力薄弱区2，此时，在应力较大的区域(第一区域12)和变形量较大的区域(第二区域13)均设置有应力薄弱区2，当电化学装置内部产气导致压力增大时，在压力作用下，位于第一区域12的应力薄弱区2受到较大的应力从而断裂形成开口，壁面1中第二区域13的位置变形量较大，从而使得该位置 的应力薄弱区2断裂形成开口，通过上述两种开口将电化学装置内部的气体排出。
以上各实施例中，应力薄弱区2的形状可以为圆弧形、直线型、折线形、曲线型等多种形状，以如图7～9所示的三种方案为例，对应力薄弱区2(以凹槽为例)的形状进行验证试验，该电池的压强上下限要求为(0.1MPa，4MPa)，试验过程中应力薄弱区的设置位置、长度、宽度、深度等参数相同，试验结果如下表：
应力薄弱区形状 试验数量 平均泄压压强/MPa 爆炸数量
1 10 2.33 0
2 10 2.59 0
3 10 0.56 0
无凹槽 10 6.2 10
虽然图7～9所示的三种方案电池均未发生爆炸，但方案3中圆弧形结构的凹槽能够在要求压强区间内更早的完成泄压，更好的降低爆炸风险。
基于此，以上各实施例中，应力薄弱区2的曲率和与应力薄弱区2距离最近的外端部11的曲率相同，例如，如图1和图2所示，当外端部11的形状为圆弧形时，该应力薄弱区2的形状为如图9所示的圆弧形，当外端部11的形状为直线形时，该应力薄弱区2的形状为直线形，当外端部11的形状为折线形时，该应力薄弱区2的形状为折线形，因此，只要满足应力薄弱区2的曲率和与应力薄弱区2距离最近的外端部11的曲率相同即可。
在一种具体实施例中，该应力薄弱区2可以为连续结构或非连续结构。如图1和图2所示，该应力薄弱区2为非连续形结构，即多个间隔分布的断点形成该应力薄弱区2。
在一种具体实施例中，该壁面1可以设置有一条或多条应力薄弱区2，且各条应力薄弱区2可以为连续形结构或非连续形结构。
在又一种具体实施例中，设置于同一壁面1的应力薄弱区2的总长度大于 或等于3mm，对于连续形结构的应力薄弱区2，该总长度即为应力薄弱区2的长度，对于图1和图2所示的非连续形结构的应力薄弱区2，该总长度为各非连续形结构的长度之和，当壁面1设置有多条应力薄弱区2时，该总长度为各条应力薄弱区2的长度之和。
本实施例中，若同一壁面1的应力薄弱区2的总长度过大，则该壁面1的强度较低，从而导致电池的结构强度较低，降低电池的使用寿命；若同一壁面1的应力薄弱区2的总长度过小，则当电池内部产气导致压力过大时，该应力薄弱区2破裂形成的开口面积较小，电池内部的气体排出所需要的时间较长，无法快速泄压，导致电池的安全性较低。本实施例中，当同一壁面1的应力薄弱区2的总长度大于或等于3mm时，使得该电池的壳体具有较高的强度和使用寿命，同时，应力薄弱区2破裂后形成的开口面积较大，能够快速将电池内部的气体排出，从而降低电池膨胀变形、甚至爆炸的风险，提高电池的安全性。
以图1和图2所示的实施例为例，对应力薄弱区2的总长度进行验证试验，该电池的压强上下限要求为(0.1MPa，4MPa)，试验过程中应力薄弱区的设置位置、形状、宽度、深度等参数相同，试验结果如下表：
Group 应力薄弱区半径R/mm 应力薄弱区长度/mm 数量 平均泄压压强/MPa 爆炸数量
6 1 1.57 10 5.62 10
7 1 3.14 10 3.36 0
8 2.5 3.925 10 2.02 0
9 2.5 7.85 10 0.56 0
10 2.5 15.7 10 0.18 0
从试验结果可知，应力薄弱区2的总长度小于3mm时，应力薄弱区2未起泄压作用，全部电池发生爆炸；当应力薄弱区2的总长度大于3mm时，电池在规定要求内泄压，有效避免电池爆炸。
在一种具体实施例，如图6所示，应力薄弱区2的深度H为壁面1的厚度的30％～90％，例如，该应力薄弱区2的深度与壁面1的厚度之比可以为：30％、50％、60％、80％、90％等。
具体地，若应力薄弱区2的深度H过大(例如大于壁面1厚度的90％)，当电池正常工作未产气时，壳体在应力薄弱区2位置的结构强度较低，容易损坏，导致电池失效，降低电池的使用寿命，且存在从应力薄弱区2的位置漏液的风险；若应力薄弱区2的深度H过小(例如小于壁面1厚度的30％)，当电池内部产气时，该深度H的应力薄弱区2断裂所需的压力较大，即只有当电池内部的压力达到较大的值时，应力薄弱区2才能形成开口，导致电池内部的气体无法快速排出。
本实施例中，当应力薄弱区2的深度H为壁面1的厚度的30％～90％，电池正常工作时，该应力薄弱区2不会明显降低壳体的结构强度，从而降低电池损坏的风险，提高使用寿命，同时，该深度的应力薄弱区2能够在电池内部产气时迅速断裂形成开口，从而迅速将电池内部的气体排出，从而降低电池膨胀变形、甚至爆炸的风险，提高电池的安全性。
以图1和图2所示的实施例为例，对应力薄弱区2的深度H进行验证试验，该电池的压强上下限要求为(0.1MPa，4MPa)，试验过程中应力薄弱区的设置位置、形状、长度、宽度等参数相同，试验结果如下表：
Group 应力薄弱区深度/壳体原厚度 试验数量 平均泄压压强/MPa 爆炸数量
1 90％ 10 0.094 0
2 70％ 10 0.16 0
3 50％ 10 0.56 0
4 30％ 10 2.29 0
5 10％ 10 3.85 4
6 无应力薄弱区 10 6.2 10
从试验结果可以看到，应力薄弱区2的深度H大于70％时泄压压强不能稳定控制在泄压下限以上，在日常使用中有发生漏液的风险；应力薄弱区2的深度H小于30％时，泄压压力无法稳定控制在泄压上限以下，有4个电池发生爆炸。所以本实施例中应力薄弱区2的深度H为壁面1的厚度的30％～70％时具有更好的安全性能。
同时，如图6所示，该应力薄弱区2的宽度W为壁面1的厚度的50％～110％。例如，应力薄弱区2的宽度W与壁面1的厚度之比可以为：50％、60％、90％、100％、110％等。可以理解，应力薄弱区2的宽度W越大，该应力薄弱区2的面积越大。
具体地，若应力薄弱区2的宽度W过大(例如大于壁面1厚度的110％)，则应力薄弱区2所占据的壁面1的面积较大，当电池正常工作未产气时，壳体在应力薄弱区2位置的结构强度较低，容易损坏，导致电池失效，降低电池的使用寿命；若应力薄弱区2的宽度W过小(例如小于壁面1厚度的50％)，该应力薄弱区2所占据的壁面1的面积过小，当电池内部产气时，应力薄弱区2断裂形成的开口过小，导致电池内部的气体无法快速排出。
本实施例中，当应力薄弱区2的宽度W为壁面1的厚度的50％～110％，电池正常工作时，该应力薄弱区2不会明显降低壳体的结构强度，从而降低电池损坏的风险，提高使用寿命，同时，该宽度W的应力薄弱区2在电池内部产气时形成的开口较大，能够迅速将电池内部的气体排出，从而降低电池膨胀变形、甚至爆炸的风险，提高电池的安全性。
以图1和图2所示的实施例为例，对应力薄弱区2的宽度W进行验证试验，该电池的压强上下限要求为(0.1MPa，4MPa)，试验过程中应力薄弱区的设置位置、形状、长度、深度等参数相同，试验结果如下表：
Group 应力薄弱区宽度/壳体原厚度 试验数量 平均泄压压强/MPa 爆炸数量
1 140％ 10 0.058 -
2 110％ 10 0.19 0
3 80％ 10 0.33 0
4 50％ 10 0.56 0
5 20％ 10 4.96 6
6 无应力薄弱区 10 6.2 10
从试验结果可以看到，应力薄弱区2的宽度W小于壁面1厚度的50％时电池压强不能稳定在上限压强要求以下，且有6个电池发生爆炸；应力薄弱区2的宽度W大于壁面1厚度的110％时，电池泄压压强不能稳定控制在下限要求以上； 该应力薄弱区2的宽度W在壁面1的厚度的50％～110％之间时，能够稳定控制泄压压强在安全范围，电池无爆炸。
以上各实施例中，该壁面1为壳体中面积最大的壁面，或者为面积次大的壁面，也就是说，本申请实施例中的应力薄弱区2设置于壳体中面积较大的壁面，该壁面的面积较大，从而具有较大的空间设置应力薄弱区2。
具体地，上述应力薄弱区2可以设置于壁面1的内表面、外表面中的至少一者，且应力薄弱区2的位置、尺寸和形状等参数由上述各实施例限定。
以上各实施例中，壁面1的弹性模量大于或等于1000Mpa，即该应力薄弱区2设置于硬度较大的壁面，该硬度的壁面1在压力作用下不易发生弹性变形，从而使得在壳体内部产气的压力作用下，应力薄弱区2发生断裂产生开口，从而将壳体内部的气体排出。
具体地，该壁面1的材质可以包括PC材质、铝塑膜、金属中的一种或多种。
本申请实施例中应力薄弱区2加工方式可以为激光切割，具有加工准确度高，效率高，对壳体其他部位损伤小的优点。
本申请的电化学装置包括发生电化学反应的任何装置，它的具体实例包括所有种类的一次电池、二次电池、燃料电池、太阳能电池或电容。特别地，该电化学装置是锂二次电池，包括锂金属二次电池、锂离子二次电池、锂聚合物二次电池或锂离子聚合物二次电池。
本申请实施例中的电化学装置可以用于多种领域，只要能够采用电化学装置供电的设备，均可采用本申请实施例中的电化学装置。例如，该电化学装置可以用于电动车的电化学装置包和电子设备等部件，电子设备可以为手机、平板电脑、桌面型计算机、膝上型计算机、手持计算机、笔记本电脑、超级移动个人计算机(ultra-mobile personal computer，UMPC)、上网本，以及蜂窝电话、个人数字助理(personal digital assistant，PDA)、增强现实(augmented reality，AR)设备、虚拟现实(virtual reality，VR)设备、人工智能(artificial intelligence,AI)设备、可穿戴式设备、车载 设备、智能家居设备和/或智慧城市设备，本申请实施例对该电子设备的具体类型不作特殊限制。
具体地，该电子设备可以包括外壳、屏幕、电路板和电化学装置等部件，其中，屏幕、电路板和电化学装置均安装于外壳，该电化学装置为以上任一实施例中所述的电化学装置。
以上所述仅为本申请的优选实施例而已，并不用于限制本申请，对于本领域的技术人员来说，本申请可以有各种更改和变化。凡在本申请的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本申请的保护范围之内。

Claims (29)

  1. 一种电化学装置，其特征在于，所述电化学装置包括：
    壳体，具有腔体，且所述壳体包括壁面(1)；
    其中，所述壁面(1)设置有应力薄弱区(2)。
  2. 根据权利要求1所述的电化学装置，其特征在于，所述应力薄弱区(2)为连续结构或非连续结构。
  3. 根据权利要求1所述的电化学装置，其特征在于，设置于同一所述壁面(1)的所述应力薄弱区(2)的总长度大于或等于3mm。
  4. 根据权利要求1所述的电化学装置，其特征在于，所述应力薄弱区(2)的深度H为所述壁面(1)的厚度的30％～90％。
  5. 根据权利要求1所述的电化学装置，其特征在于，所述应力薄弱区(2)的宽度W为所述壁面(1)的厚度的50％～110％。
  6. 根据权利要求1所述的电化学装置，其特征在于，所述壁面(1)设置有一个或多个应力薄弱区(2)。
  7. 根据权利要求1所述的电化学装置，其特征在于，所述壁面(1)为所述壳体中面积最大的壁面。
  8. 根据权利要求1所述的电化学装置，其特征在于，所述壁面(1)的内表面、外表面中的至少一者设置有所述应力薄弱区(2)。
  9. 根据权利要求1所述的电化学装置，其特征在于，所述壁面(1)的弹性模量大于或等于1000MPa。
  10. 根据权利要求1所述的电化学装置，其特征在于，所述应力薄弱区(2)包括刻痕、凹槽、强度低于其周围区域材料的区域中的至少一种。
  11. 根据权利要求1所述的电化学装置，其特征在于，所述壁面(1)具有外端部(11)，所述应力薄弱区(2)的曲率和与所述应力薄弱区(2)距 离最近的所述外端部(11)的曲率相同。
  12. 根据权利要求1所述的电化学装置，所述壁面(1)具有外端部(11)和第一区域(12)，所述第一区域(12)具有第一外边缘(122)，所述第一外边缘(122)与所述外端部(11)重合；所述应力薄弱区(2)设置于所述第一区域(12)；
    所述第一区域(12)的面积与所述壁面(1)的面积之比为30％～50％。
  13. 根据权利要求12所述的电化学装置，其特征在于，所述第一区域(12)为环形结构，所述第一区域(12)具有第一内边缘(121)；所述第一内边缘(121)为所述第一外边缘(122)上的各点沿其法线或垂线方向，向所述壁面(1)内部延伸相同的第一距离L1形成的线段所连接成的圈。
  14. 根据权利要求12所述的电化学装置，其特征在于，所述第一区域(12)为环形结构，所述第一区域(12)具有第一内边缘(121)；所述第一内边缘(121)为：所述第一外边缘(122)上的各点沿其法线或垂线方向向所述壁面(1)内部延伸相同的第一距离L1形成线段，其中，所述线段具有非连接处，与所述非连接处相邻的两条所述线段进一步根据形成所述两条线段的第一外边缘(122)相同曲率进行延伸至相交所连接成的圈。
  15. 根据权利要求13所述的电化学装置，其特征在于，所述外端部(11)与所述壁面(1)的几何中心之间具有第二距离L2，所述第一距离L1与所述第二距离L2满足：0.1≤L1/L2≤0.4。
  16. 根据权利要求13所述的电化学装置，其特征在于，所述外端部(11)和所述第一内边缘(121)均为圆弧形；
    所述第一内边缘(121)与所述几何中心之间的距离为R1，所述外端部(11)的半径为R，0.7≤R1/R≤0.8。
  17. 根据权利要求16所述的电化学装置，其特征在于，所述壁面(1)为圆形，所述第一区域(12)为圆环形；
    所述第一区域(12)的内径为R1，外径为R；
    其中，
    Figure PCTCN2020108396-appb-100001
  18. 根据权利要求13所述的电化学装置，其特征在于，所述壁面(1)为矩形，所述第一区域(12)为矩形环；
    所述壁面(1)的边长分别为t1、t2时，所述第一距离L1、t1、t2满足关系(t1-2L1)×(t2-2L1)＝0.55t1×t2。
  19. 根据权利要求14所述的电化学装置，其特征在于，所述壁面(1)为不对称形状，所述第一区域(12)为不对称环。
  20. 根据权利要求14所述的电化学装置，其特征在于，所述壁面(1)为L形，所述第一区域(12)为L形环；
    所述壁面(1)的各边长分别为t1、t2、t3、t4、t5、t6，当t2＝t4+t6、t3＝t1+t5时，所述第一距离L1、t1、t2、t3、t4、t5、t6满足关系：0.45×(t2×t3-t5×t6)＝(t2×t3-(t2-2L1)×(t3-2L1))。
  21. 根据权利要求20所述的电化学装置，其特征在于，所述第一区域(12)为不对称L形环。
  22. 根据权利要求1所述的电化学装置，其特征在于，所述壁面(1)具有外端部(11)和第二区域(13)，且所述应力薄弱区(2)设置于所述第二区域(13)；所述第二区域(13)具有第二外边缘(131)；所述第二外边缘(131)为所述第一外边缘(122)上的各点沿其法线或垂线方向，向所述壁面(1)内部延伸相同的第三距离L3形成的线段所连接成的圈；
    所述第二区域(13)的面积与所述壁面(1)的面积之比为10％～22％。
  23. 根据权利要求1所述的电化学装置，其特征在于，所述壁面(1)具有外端部(11)和第二区域(13)，且所述应力薄弱区(2)设置于所述第二区域(13)；所述第二区域(13)具有第二外边缘(131)；所述第二外边缘(131)为：所述第一外边缘(122)上的各点沿其法线或垂线方向向所述壁面(1)内部延伸相同的第三距离L3形成线段，其中，所述线段具有非连接处， 与所述非连接处相邻的两条所述线段进一步根据形成所述两条线段的第一外边缘(122)相同曲率进行延伸至相交所连接成的圈；
    所述第二区域(13)的面积与所述壁面(1)的面积之比为10％～22％。
  24. 根据权利要求22所述的电化学装置，其特征在于，所述外端部(11)与所述壁面(1)的几何中心之间具有第二距离L2，所述第三距离L3与所述第二距离L2满足：0.2≤L3/L2≤0.5。
  25. 根据权利要求24所述的电化学装置，其特征在于，所述外端部(11)和所述第二外边缘(131)均为圆弧形；
    所述第二外边缘(131)与所述几何中心之间的距离为R2，所述外端部(11)的半径为R，0.3≤R2/R≤0.5。
  26. 根据权利要求25所述的电化学装置，其特征在于，所述壁面(1)和所述第二区域(13)均为圆形；
    其中，
    Figure PCTCN2020108396-appb-100002
  27. 根据权利要求22所述的电化学装置，其特征在于，所述壁面(1)和所述第二区域(13)均为矩形；
    所述壁面(1)的边长分别为t1、t2时，所述第三距离L3、t1、t2满足关系(t1-2L3)×(t2-2L3)＝0.2t1×t2。
  28. 根据权利要求23所述的电化学装置，其特征在于，所述壁面(1)和所述第二区域(13)均为L形；
    所述壁面(1)的各边长分别为t1、t2、t3、t4、t5、t6，且t2＝t4+t6、t3＝t1+t5时，所述第三距离L3、t1、t2、t3、t4、t5、t6满足关系：(t3-2L3)×(t4-2L3)+t6×(t1-2L3)＝0.2×(t2×t3-t5×t6)。
  29. 一种电子设备，其特征在于，所述电子设备包括：
    外壳；
    屏幕，安装于所述外壳；
    电化学装置，位于所述外壳的内腔；
    其中，所述电化学装置为权利要求1～28中任一项所述的电化学装置。
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CN216980796U (zh) * 2022-05-12 2022-07-15 比亚迪股份有限公司 防爆阀、电池、电池模组、电池包以及车辆
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20020071178A (ko) * 2001-03-05 2002-09-12 삼성에스디아이 주식회사 안전수단을 포함하는 전지
CN101944632A (zh) * 2009-07-06 2011-01-12 Sb锂摩托有限公司 锂离子电池
KR20120094693A (ko) * 2011-02-17 2012-08-27 주식회사 엘지화학 안전판이 구비된 각형 이차전지
CN202585583U (zh) * 2012-03-19 2012-12-05 宁德新能源科技有限公司 一种电池
CN203707194U (zh) * 2014-01-16 2014-07-09 深圳市豪鹏科技有限公司 二次电池
CN208014752U (zh) * 2018-04-27 2018-10-26 深圳市比克动力电池有限公司 一种圆柱锂离子电池防爆外壳及其成型模具
CN209401714U (zh) * 2019-04-09 2019-09-17 江苏塔菲尔新能源科技股份有限公司 一种具有防爆设计的锂离子电池

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7195839B2 (en) * 2003-02-11 2007-03-27 Eveready Battery Company, Inc. Battery cell with improved pressure relief vent
JP6536354B2 (ja) * 2015-11-02 2019-07-03 株式会社村田製作所 電池、電池パック、電子機器、電動車両、蓄電装置および電力システム
CN207572408U (zh) * 2017-12-13 2018-07-03 宁德新能源科技有限公司 电化学装置壳体以及电化学装置

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20020071178A (ko) * 2001-03-05 2002-09-12 삼성에스디아이 주식회사 안전수단을 포함하는 전지
CN101944632A (zh) * 2009-07-06 2011-01-12 Sb锂摩托有限公司 锂离子电池
KR20120094693A (ko) * 2011-02-17 2012-08-27 주식회사 엘지화학 안전판이 구비된 각형 이차전지
CN202585583U (zh) * 2012-03-19 2012-12-05 宁德新能源科技有限公司 一种电池
CN203707194U (zh) * 2014-01-16 2014-07-09 深圳市豪鹏科技有限公司 二次电池
CN208014752U (zh) * 2018-04-27 2018-10-26 深圳市比克动力电池有限公司 一种圆柱锂离子电池防爆外壳及其成型模具
CN209401714U (zh) * 2019-04-09 2019-09-17 江苏塔菲尔新能源科技股份有限公司 一种具有防爆设计的锂离子电池

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4170803A4 *

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