WO2023184400A1 - 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

Info

Publication number
WO2023184400A1
WO2023184400A1 PCT/CN2022/084560 CN2022084560W WO2023184400A1 WO 2023184400 A1 WO2023184400 A1 WO 2023184400A1 CN 2022084560 W CN2022084560 W CN 2022084560W WO 2023184400 A1 WO2023184400 A1 WO 2023184400A1
Authority
WO
WIPO (PCT)
Prior art keywords
tab
housing
tabs
electrode assembly
electrochemical device
Prior art date
Application number
PCT/CN2022/084560
Other languages
English (en)
French (fr)
Inventor
林森
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.)
Filing date
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/CN2022/084560 priority Critical patent/WO2023184400A1/zh
Priority to CN202280010285.XA priority patent/CN116830371A/zh
Publication of WO2023184400A1 publication Critical patent/WO2023184400A1/zh

Links

Images

Classifications

    • 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
    • H01M50/289—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by spacing elements or positioning means within frames, racks or packs
    • 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 field of battery technology, and in particular to an electrochemical device and electronic equipment.
  • the series/parallel battery in the same bag includes a casing and multiple electrode assemblies arranged in the same casing.
  • the series-connected electrode assemblies need to be separated by separators to avoid high voltage.
  • the electrolyte decomposes under voltage, and parallel electrode assemblies are separated by separators to avoid mutual interference.
  • the inventor of this application found through research that when the tabs of multiple electrode assemblies protrude from the sealing edge on the same side of the case in the same bag of series/parallel batteries, the sealing edge will have insufficient packaging reliability. , there are security risks.
  • this application provides an electrochemical device and an electronic device to improve the packaging reliability of series/parallel batteries in the same bag.
  • the first aspect of this application provides an electrochemical device, including a housing, at least one separator, and at least two electrode assemblies.
  • the housing includes a first housing and a second housing.
  • the partition is disposed between the first housing and the second housing, so that the electrochemical device is provided with at least two cavities between the first housing and the second housing.
  • the electrode assembly includes a pole piece assembly and at least two tabs connected to the pole piece assembly. The pole piece assembly is received in the cavity.
  • the electrochemical device includes a first sealing part, the first sealing part includes a first sealing edge; along the thickness direction of the first sealing part, the maximum distance between the pole tabs located in the first sealing part at the first sealing edge is d, the thickness of the electrochemical device is D, and satisfies: d ⁇ 0.4D.
  • the surface flatness of the first sealing part can be improved, and the height difference between the tabs in the thickness direction of the first sealing part is too large, resulting in the case and the separator being at the first sealing part.
  • the side wall of the shell can provide appropriate strain for the package at the under-voltage point of the first sealing part, promoting the connection between the case and the partition at the under-voltage point. packaging, thereby improving the reliability of the packaging.
  • the electrochemical device meets at least one of the following conditions: (1) d ⁇ 0.15D; (2) d ⁇ 2mm.
  • the flatness of the position of the first sealing part can be further improved, thereby improving the uniformity of pressure everywhere when the housing and the partition are sealed at the first sealing part, thereby further improving the The packaging reliability of the first sealing part.
  • At least two tabs of at least one electrode assembly protrude from the first side end of the housing, and at least two tabs of at least one electrode assembly protrude from the second side of the housing.
  • the first side end is adjacent to or opposite to the second side end. Therefore, it can be avoided that multiple tabs of multiple electrode assemblies are on the same side of the housing and occupy too much space. At the same time, multiple tabs distributed on different sides of the housing can also meet different connection requirements.
  • At least two tabs of at least one electrode assembly protrude from the first side end and the second side end of the housing respectively. Therefore, electrode assemblies with at least two tabs extending from the first side end or the second side end can be conveniently connected in series through the two tabs of the electrode assembly.
  • the separator includes a first encapsulation layer, a second encapsulation layer and an intermediate layer, the intermediate layer being located between the first encapsulation layer and the second encapsulation.
  • the electrode assembly includes an adjacent first electrode assembly and a second electrode assembly
  • the separator includes a first separator located between the first electrode assembly and the second electrode assembly
  • the tabs of the first electrode assembly include first tabs
  • the tabs of the second electrode assembly include second tabs adjacent to the first tabs, along the length direction of the first sealing edge.
  • the distance between the first pole tab and the second pole tab at the first sealing edge is L
  • the thickness of the first separator is T
  • L/T ⁇ 15 L/T ⁇ 15.
  • the offset arrangement of the first and second poles compared to the overlapping arrangement of the first and second poles, can reduce the difference in seal thickness of the first seal part and improve the packaging reliability at the poles;
  • the bending degree of the separator between the tabs can be effectively reduced, so that the stress and strain suffered by it is smaller, and the separator at the side corner of the tab can fit better during sealing
  • Other components connected to it such as the housing are not easily peeled off when the tab is pulled by external stress, thereby further improving packaging reliability.
  • the electrochemical device meets at least one of the following conditions: (1) The thickness of the first tab is h 1 and L/h 1 ⁇ 10; (2) The thickness of the second tab is h 2 , L/h 2 ⁇ 10; at this time, the bending degree of the separator between the tabs can be further reduced, so that the stress and strain suffered by the separator is smaller, and the separation of the separator between the first tab and/or the second tab can be further improved.
  • the fit between the side corners of the tabs and other components further improves packaging reliability.
  • the electrochemical device satisfies at least one of: (3)L/(h 1 +T) ⁇ 5; (4)L/(h 2 +T) ⁇ 5; (5)h 1 ⁇ 0.2mm; ( 6)h 2 ⁇ 0.2mm.
  • the bending degree of the separator between the tabs can be further reduced, so that the stress and strain it is subjected to is smaller, and the separation between the separator and other components at the side corners of the first tab and/or the second tab can be further improved. fit, thereby further improving packaging reliability.
  • the pole piece assembly includes at least one of a wound structure or a lamination structure.
  • this application also provides an electronic device, including the above electrochemical device.
  • the electrochemical device provided by the present application uses the maximum distance d between the poles of the first sealing part along the thickness direction of the first sealing part at the first sealing edge. , and the thickness D of the electrochemical device satisfies d ⁇ 0.4D.
  • the flatness of the position of the first sealing part can be improved, and the height difference of the tab in the thickness direction of the first sealing part is too large, which may cause the case and the separator to be packaged at the first sealing part due to excessive local distortion.
  • Under-voltage leads to the risk of weak seal strength.
  • the side wall of the shell can provide appropriate strain for the package at the under-pressure point of the first sealing part, promoting the sealing between the case and the partition at the under-voltage point, thereby improving The packaging reliability of the first sealing part.
  • Figure 1 is a schematic structural diagram of an electrochemical device according to one embodiment of the present application.
  • Figure 2 is a schematic diagram cut along line MM' in Figure 1;
  • Figure 3 is a schematic diagram of the pole piece assembly in a wound structure in one embodiment
  • Figure 4 is a schematic diagram of another embodiment when the pole piece assembly is a laminated structure
  • Figure 5 is a schematic diagram cut along the XY plane in Figure 1;
  • Figure 6 is a front view of Figure 1;
  • Figure 7 is an enlarged view of part B of Figure 6;
  • Figure 8 is a schematic diagram of part of the structure in Figure 7;
  • Figure 9 is a partial structural schematic diagram of the electrochemical device in the right view of Figure 1;
  • FIG. 10 is a schematic structural diagram of an electrochemical device with multi-side output tabs in another embodiment.
  • an electrochemical device 100 provided by one embodiment of the present application includes a housing 10 , an electrode assembly 20 and a separator 30 .
  • the housing 10 includes a first housing 12 and a second housing 14.
  • the housing 10 is used to limit a closed space for accommodating the electrode assembly 20.
  • the partition 30 is located between the first housing 12 and the second housing 14.
  • the plate 30 serves to separate the interior space of the housing 10 , thereby increasing the number of independent cavities inside the housing 10 .
  • the electrochemical device 100 may include one partition 30 or multiple partitions 30 .
  • one partition 30 may separate the internal space of the housing 10 into two independent spaces. cavity.
  • the electrochemical device 100 includes a plurality of partitions 30, the plurality of partitions 30 can divide the internal space of the housing 10 into a plurality of independent cavities.
  • Two partitions 30 can divide the internal space of the housing 10 into three independent cavities; when the electrochemical device 100 includes three partitions 30, the three partitions 30 divide the internal space of the housing 10 into four. an independent cavity.
  • the electrochemical device 100 includes one separator 30 .
  • a partition 30 divides the internal space of the housing 100 into two independent cavities, which are respectively called the first cavity 101 and the second cavity 102 .
  • the electrochemical device 100 may include two electrode assemblies 20 or may include three or more electrode assemblies 20 .
  • the electrochemical device 100 includes two electrode assemblies 20 as an example.
  • the two electrode assemblies 20 are a first electrode assembly 20a and a second electrode assembly 20b respectively.
  • the electrochemical device 100 has a separator 30, and the separator 30 separates two independent cavities, the first electrode assembly 20a is disposed in the aforementioned first cavity 101, and the second electrode assembly 20b is disposed in the aforementioned first cavity 101.
  • the first electrode assembly 20a, the separator 30, and the second electrode assembly 20b are distributed along the first direction Z, and the first direction Z is the same as the thickness direction of the separator 30.
  • the electrode assembly 20 includes a pole piece assembly 21 and a pole tab 22 connected to the pole piece assembly 21 .
  • the number of pole tabs 22 is at least two, and at least two pole tabs 22 have a gap between them.
  • the pole piece assembly 21 includes a first pole piece 211, a second pole piece 212, and an isolation film 213.
  • the isolation film 213 is disposed between the first pole piece 211 and the second pole piece 212.
  • the first pole piece The polarity of 211 is opposite to that of the second pole piece 212, and the isolation film 213 is used to reduce the risk of short circuit between the first pole piece 211 and the second pole piece 212.
  • the plurality of tabs 22 of the electrode assembly 20 may all protrude from the first side end of the housing 10 .
  • the plurality of tabs 22 of the electrode assembly 20 can also protrude from different side ends of the housing 10 , that is, at least two tabs 22 of one electrode assembly 20 extend from the first side end of the housing 10 . Extending, at least two tabs 22 of the other electrode assembly 20 extend from the second side end of the housing.
  • the first side end of the housing 10 and the second side end of the housing 10 are opposite ends.
  • the first side end of the housing 10 and the second side end of the housing 10 are opposite ends. The second side ends are two adjacent ends.
  • the pole piece assembly 21 may be a rolled structure, that is, the first pole piece 211 , the second pole piece 212 and the isolation film 213 are stacked and rolled.
  • the pole piece assembly 21 may have a laminated structure. In this case, the number of the first pole piece 211 , the second pole piece 212 and the isolation film 213 is multiple.
  • the isolation film 213 is located at Between an adjacent first pole piece 211 and a second pole piece 212, the first pole piece 211, the isolation film 213 and the second pole piece 212 are stacked along one direction, which direction is the first pole piece 211, the isolation film 213 and the second pole piece 212.
  • the thickness direction of the isolation film 213 or the second pole piece 212 is a rolled structure, that is, the first pole piece 211 , the second pole piece 212 and the isolation film 213 are stacked and rolled.
  • the pole piece assembly 21 may have a laminated structure. In this case, the number of the first pole piece 211 , the second pole piece
  • the structure of the pole piece assembly of the first electrode assembly 20a and the pole piece assembly of the second electrode assembly 20b can be the same, that is, the pole piece assembly of the first electrode assembly 20a and the pole piece assembly of the second electrode assembly 20b can both be It is a winding structure or a laminated structure.
  • the structure of the pole piece assembly of the first electrode assembly 20a and the pole piece assembly of the second electrode assembly 20b can also be different, that is, one of the pole piece assembly of the first electrode assembly 20a and the pole piece assembly of the electrode assembly 20b is a coiled structure, and the other may be a coiled structure.
  • one of the tabs of the first electrode assembly 20a is called the first tab 221.
  • the first tab 221 may be a positive tab or a negative tab.
  • one of the tabs of the second electrode assembly 20b is called the second tab 222.
  • the second tab 222 may be a positive tab or a negative tab.
  • the polarities of the first tab 221 and the second tab 222 may be the same or different.
  • the first tab 221 and the second tab 222 may or may not be electrically connected to each other.
  • the separator 30 includes a first sealing area 31 .
  • the portion of the separator 30 located in the first sealing area 31 is sealed with other components. That is, the separator 30 is fixedly connected to other components in the first sealing area 31 (which may be hot-melt connection or bonding).
  • both side walls of the first sealing area 31 of the separator 30 are connected to the housing 10 .
  • the electrochemical device 100 has two separators 30
  • one side wall of the first sealing area 31 of one separator 30 is connected to the other separator 30
  • the other side wall is connected to the housing 10 .
  • the number of partitions 30 is three or more, both side walls of the first sealing area 31 of the middle partition 30 are connected to other partitions 30 located on both sides of the partition 30 .
  • the first sealing area 31 can be in the shape of a "back", and the first sealing area 31 can extend to the outer edge of the partition 30 , and the first sealing area 31 can also be spaced a certain distance from the outer edge of the partition 30 .
  • the separator 30 includes a first encapsulation layer, a second encapsulation layer, and an intermediate layer located between the first encapsulation layer and the second encapsulation layer.
  • the first encapsulation layer and the second encapsulation layer are both made of heat-fusible material, such as PP material.
  • the electrochemical device 100 includes a first sealing part 103 .
  • the housing 10 and the separator 30 are sealed at the first sealing part 103 . That is, the housing is sealed at the first sealing part 103 .
  • 10 is fixedly connected to the partition 30 (it can be hot-melt connection or bonding).
  • the first sealing part 103 includes a first sealing edge 1031 , and the first sealing edge 1031 is the side of the first sealing part 103 away from the cavity space of the housing 10 .
  • the first sealing part 103 may be in the shape of a "return", that is, the four sides of the housing 10 are used to be connected and fixed with the partition. In this case, the housing 10 is two parts that can be separated relatively.
  • first sealing part 103 may also be in a "concave" shape, that is, the housing 10 is two parts integrally connected, and each part has a concave cavity space. The two parts can be interlocked and connected with each other. The partition connection is fixed.
  • the housing 10 is formed by two parts that are relatively separable and are fixedly connected.
  • the thickness direction of the first sealing part 103 that is, along the first direction Z, between the tabs 22 of the first sealing part 103 at the third
  • the maximum distance at the seal edge 1031 is d
  • the thickness of the electrochemical device is D
  • d ⁇ 0.4D is satisfied.
  • the maximum distance d is the distance between the two farthest surfaces of the two tabs along the thickness direction of the first sealing part 103 .
  • the first tab 221 and the second tab 222 both extend out of the housing 10 at the first sealing edge 1031 .
  • the maximum distance between the tabs 22 located in the first sealing part at the first sealing edge 1031 may be At the sealing edge 1031 , the distance between the first pole tab 221 and the second pole tab 222 in the thickness direction of the first sealing part 103 .
  • d/D can be 0.1, 0.2, 0.3 or 0.4, etc. In a specific example, when D is 3.3mm, d ⁇ 1.32mm.
  • the inventor of the present application found that since parts of the first tab 221 and the second tab 222 extend out of the housing 10 from the first sealing portion 103 for connection with the outside, the first tab 221 and the second tab
  • the area of the ear 222 located at the first sealing portion 103 has a thickness, which will affect the sealing effect of the first sealing portion 103 .
  • at least some of the tabs of multiple electrode assemblies in different cavities need to protrude out of the housing 10 , and the thickness of the multiple tabs is continuously accumulated, further affecting the reliability of the seal of the first sealing part 103 .
  • the inventor of the present application found through research that along the thickness direction of the first sealing part 103, the maximum distance d between the first tab 221 and the second tab 222 at the first sealing edge 1031 satisfies d ⁇ 0.4D , the first sealing part 103 can have higher packaging reliability. This is because satisfying the above relationship is conducive to the appropriate flatness of the packaging plane of the first sealing part 103.
  • the side wall of the housing 10 can provide appropriate strain for the packaging at the undervoltage point of the first sealing part 103, promoting undervoltage. The sealing between the housing 10 and the partition 30 is carried out, thereby improving the sealing reliability of the first sealing part 103.
  • At least one of the following relationships is satisfied: (1) d ⁇ 0.15D; (2) d ⁇ 2mm.
  • the flatness of the surface of the first sealing part can be further improved, thereby improving the uniformity of pressure everywhere when the housing and the partition are sealed at the first sealing part, thereby further improving the The packaging reliability of the first sealing part 103.
  • both the first tab 221 and the second tab 222 extend out of the housing 10 from the first sealing edge 1031 .
  • the thickness of the partition 30 is T, that is, along the first direction Z in FIG. 7
  • the thickness of the partition 30 is T.
  • the minimum distance between the first pole tab 221 and the second pole tab 222 at the first sealing edge 1031 is L, and L/T ⁇ 15.
  • L/T may be 15, 20, 25, 30, or 100, etc.
  • T is 0.2mm
  • L ⁇ 3mm when T is 0.2mm, L ⁇ 3mm.
  • the inventor of the present application found that since the first tab 221 and the second tab 222 are located on both sides of the separator 30, on the one hand, the arrangement of the tabs will have a greater impact on the reliability of the package. Compared with the first tab, The pole tabs 221 and the second pole tabs 222 are overlapped, and the first pole tabs 221 and the second pole tabs 222 are arranged in an offset manner, which can reduce the seal thickness difference at the first sealing part 103 and improve the packaging reliability at the pole tabs; another On the other hand, when the first pole tab 221 and the second pole tab 222 are disposed in an offset manner, the portion of the separator 30 between the first pole tab 221 and the second pole tab 222 is bent along the length direction of the first sealing edge 1031 , the packaging reliability here is affected.
  • the inventor of the present application found through research that when the minimum distance L between the first tab 221 and the second tab 222 at the first sealing edge 1031 and the thickness T of the separator 30 satisfy L/T ⁇ 15, the electrical The chemical device 100 has high packaging reliability. This is because satisfying the above relationship can effectively reduce the bending degree of the separator 30 between the tabs, so that the stress and strain suffered by the separator 30 is smaller, and the separator 30 between the first tab 221 and the second tab 222 can The part can better fit other components connected to it during sealing, and will not be easily peeled off when the separator is pulled by external stress, thereby further improving packaging reliability.
  • the thickness dimension of the first pole tab 221 and the second pole tab 222 along the first direction Z and the distance between the first pole tab 221 and the second pole tab 222 along the second direction Y satisfy a certain requirement.
  • the relationship can further improve the fit of the portion of the separator 30 between the first tab 221 and the second tab 222 with other components during sealing.
  • the electrochemical device 100 can satisfy at least one of the following relationships: (3) The thickness of the first tab 221 is h 1 , and L/h 1 ⁇ 10 ; (4) The thickness of the second tab 222 is h 2 , and L/h 2 ⁇ 10.
  • the bending degree of the portion of the separator 30 located between the first tab 221 and the second tab 222 can be further reduced, so that the stress and strain suffered by the separator 30 is smaller, and the bending degree of the separator 30 between the first tab 221 can be further improved.
  • the part between the second tab 222 and other components further improves packaging reliability.
  • L/h 1 ⁇ 10 under the premise of L/T ⁇ 15, L/h 1 ⁇ 10 can also be made. Or in another embodiment, on the premise that L/T ⁇ 15, L/h 2 is also set to ⁇ 10. Or in another embodiment, under the premise of L/T ⁇ 15, L/h 1 ⁇ 10 and L/h 2 ⁇ 10 are also set.
  • the thickness T of the partition 30 is 0.2mm, h 1 is 0.1mm, and h 2 is 0.1mm, under the condition of L/T ⁇ 15, the minimum value of L is 3mm; L/h 1 Under the condition of ⁇ 10, the minimum value of L is 1mm; under the condition of L/h 2 ⁇ 10, the minimum value of L is 1mm. It can be concluded that the final minimum value of L is 3mm.
  • L/h 1 ⁇ 10 and/or L/h 2 ⁇ 10 is used to define the distance between the first tab 221 and the second tab 222 along the second direction Y, the packaging reliability of the electrochemical device 100 can be further ensured. .
  • the electrochemical device 100 can also satisfy at least one of the following characteristics: (5) L/(h 1 +T) ⁇ 5; (6) L/(h 2 +T) ⁇ 5; this When , the bending degree of the portion of the separator 30 located between the first tab 221 and the second tab 222 can be further reduced, so that the stress and strain suffered by the separator 30 is smaller, and the connection between the first tab 221 and the second tab 222 of the separator is further improved.
  • the part between the diode lugs 222 is in good fit with other components, thereby further improving packaging reliability.
  • the electrochemical device 100 satisfies conditions (5) and (6) at the same time.
  • T is 0.2mm
  • h 1 is 0.2mm
  • h 2 is 0.2mm
  • the minimum value of L is 3mm
  • the minimum value of L is 2mm
  • the minimum value of L is 2mm.
  • the final minimum value of L is 3mm.
  • L ⁇ 3mm; and/or T ⁇ 0.3mm L ⁇ 3mm; and/or T ⁇ 0.3mm.
  • T ⁇ 0.3 mm the thickness of the separator 30 can be prevented from being too large, and the separator 30 can be reduced from occupying too much space in the electrochemical device 100 , thereby reducing the energy density of the electrochemical device 10 .
  • the electronic device 200 of the present application is not particularly limited and may be any electronic device known in the art.
  • the electronic device 200 includes, but is not limited to, a notebook computer, a pen input computer, a mobile computer, an e-book player, a portable telephone, a portable fax machine, a portable copy machine, a portable printer, a stereo headset, a video recorder, an LCD television, a portable Cleaner, portable CD player, mini CD, transceiver, electronic notepad, calculator, memory card, portable recorder, radio, backup power supply, motor, automobile, motorcycle, power-assisted bicycle, bicycle, lighting equipment, toys, games Machines, clocks, power tools, flashlights, cameras, large household batteries and lithium-ion capacitors, etc.
  • the method of preparing the electrochemical device of the present application is not particularly limited, and any method known in the art can be used.
  • the present application can be prepared by the following preparation method:
  • Preparation of negative electrode sheet Prepare the negative active material, binder and solvent into a slurry, and stir evenly. The slurry is evenly coated on the negative electrode current collector and dried to obtain a single-sided coated negative electrode piece. Repeat the above steps on the other surface of the negative electrode current collector to obtain a double-sided coated negative electrode piece. Then, it is cold pressed, cut and ready for use.
  • the structure of the electrode assembly can be a winding structure or a laminated structure, in which multiple negative electrode pieces, separators, and positive electrode pieces are stacked and fixed in sequence to form an electrode assembly with a laminated structure; Negative electrode pieces, separators, and positive electrode pieces are stacked and rolled in sequence to form an electrode assembly with a rolled structure; each electrode assembly includes a positive electrode tab and a negative electrode tab; repeating the above steps can obtain multiple electrode assemblies.
  • Partitions Any partitions known in the art can be used.
  • Electrode assembly assembly Place the packaging shell in the assembly fixture, then set the electrode assembly and the separator at intervals, and lead all the tabs of the electrode assembly out of the packaging shell for subsequent processing, and finally perform top sealing and side sealing. Seal it and leave the filling port.
  • Liquid injection packaging Inject electrolyte into multiple cavities respectively, and seal after hot pressing, chemical formation, and degassing.
  • the electrochemical device provided by this application may contain two electrode assemblies, or may contain more than three electrode assemblies.
  • the preparation method of an electrochemical device containing two electrode assemblies or three or more electrode assemblies can refer to the above-mentioned preparation method of an electrochemical device.
  • the separator, negative electrode piece, separator, and positive electrode piece are stacked in sequence to form a laminate structure, and then the four corners of the entire laminate structure are fixed for use.
  • Each electrode assembly contains a positive tab and a negative tab.
  • the positive tab is aluminum (Al) and the negative tab is nickel (Ni).
  • the two tabs are arranged side by side.
  • the thickness h of the positive and negative tabs is 0.2mm, the width of the tab is 5mm; the diaphragm is made of polyethylene (PE) film with a thickness of 15 ⁇ m.
  • Preparation of separators Evenly disperse the encapsulation layer material polypropylene (PP, melting point: 140°C) into the dispersant N-methylpyrrolidone (NMP) to prepare a PP suspension; use a glue coater to The aluminum layer with a thickness of 50 ⁇ m is coated with PP suspension on both sides, and then dried at 130°C. The thickness of the PP encapsulation layer on one side of the aluminum layer is 25 ⁇ m, and the total thickness T of the separator is 100 ⁇ m.
  • PP polypropylene
  • NMP N-methylpyrrolidone
  • Electrode assembly assembly Place the punched aluminum-plastic film (thickness 150 ⁇ m) in the assembly fixture, with the pit facing upward, place the first electrode assembly in the pit, and place the first electrode assembly at the edge of the aluminum-plastic film
  • the tab glue is provided in the area corresponding to the tab of the electrode assembly, and then the separator is placed on the first electrode assembly so that the edges are aligned, and external force is applied to compress to obtain an assembled semi-finished product.
  • Place the second electrode assembly on the separator so that the edges are aligned, apply external force to compress it, and then place the other punched aluminum plastic film pit face up.
  • the second electrode component is covered with a lower surface, and tab glue is provided at the edge of the aluminum-plastic film in the area corresponding to the tab of the second electrode component.
  • the positive and negative electrode tabs of the first electrode assembly and the second electrode assembly are led out of the aluminum plastic film, and are top-sealed and side-sealed by hot pressing to obtain an assembled electrode assembly.
  • the distance L between the negative electrode tab of the first electrode assembly and the positive electrode tab of the second electrode assembly is 5 mm.
  • Liquid injection packaging Inject electrolyte into each cavity separately, and seal after hot pressing, forming, and degassing.
  • Example 1-1 The difference from Example 1-1 is that the thickness D of the lithium ion battery is 3.3 mm.
  • Example 1-1 The difference from Example 1-1 is that the thickness of the aluminum layer in the separator is 20 ⁇ m, the thickness of the PP packaging layer on one side of the aluminum layer is 15 ⁇ m, the total thickness T of the separator is 50 ⁇ m; the thickness D of the lithium-ion battery is 3.3 mm; The height difference d of the pole tab on the same side is 0.66mm.
  • the difference from Examples 1-3 is that the thickness D of the lithium-ion battery is 10 mm; the height difference d of the tabs on the same side is 0.5 mm.
  • Example 1-1 The difference from Example 1-1 is that the height difference d of the pole tab on the same side is 0.6 mm.
  • Example 1-1 The difference from Example 1-1 is that the thickness D of the lithium-ion battery is 3.3 mm; the height difference d of the tab on the same side is 0.6 mm.
  • the difference from Examples 1-3 is that the height difference d of the pole tab on the same side is 0.5 mm.
  • the difference from Examples 1-3 is that the thickness D of the lithium-ion battery is 6 mm; the height difference d of the tabs on the same side is 0.6 mm.
  • Example 1-3 The difference from Example 1-3 is that the thickness D of the lithium-ion battery is 10 mm; the height difference d of the tab on the same side is 1.0 mm.
  • Example 1-1 The difference from Example 1-1 is that the thickness D of the lithium ion battery is 10 mm.
  • Example 1-1 The difference from Example 1-1 is that the thickness of the aluminum layer in the separator is 100 ⁇ m, the thickness of the PP packaging layer on one side of the aluminum layer is 25 ⁇ m, the total thickness T of the separator is 150 ⁇ m; the thickness D of the lithium-ion battery is 10 mm; the same The height difference d of the side pole ears is 2mm.
  • Example 1-1 The difference from Example 1-1 is that the thickness D of the lithium-ion battery is 4 mm; the height difference d of the tabs on the same side is 2 mm.
  • Example 1-11 The difference from Example 1-11 is that the thickness of the aluminum layer in the separator is 100 ⁇ m, the thickness of the PP packaging layer on one side of the aluminum layer is 50 ⁇ m, and the total thickness T of the separator is 0.2 mm.
  • Example 2-2 The difference between Example 2-2 and Example 2-1 is that the adjustment L is 3mm; h is 0.1mm.
  • Example 2-3 The difference between Example 2-3 and Example 2-1 is that L is adjusted to 4mm; the thickness of the aluminum layer in the separator is 50 ⁇ m, the thickness of the single-layer PP encapsulation layer is 25 ⁇ m, and the total thickness T of the separator is 0.1 mm; h is 0.3mm.
  • Example 2-4 The difference between Example 2-4 and Example 2-1 is that the adjustment L is 4mm; h is 0.3mm.
  • Example 2-5 The difference between Example 2-5 and Example 2-3 is that the adjustment L is 10mm; h is 0.1mm.
  • Example 2-6 The difference between Example 2-6 and Example 2-3 is that the adjustment L is 3mm; h is 0.2mm.
  • Embodiment 2-7 The difference between Embodiment 2-7 and Embodiment 2-1 is that the negative electrode tab of the first electrode assembly and the positive electrode tab of the second electrode assembly are adjusted to overlap and lead out, that is, L is 0 mm.
  • Example 2-8 The difference between Example 2-8 and Example 2-1 is that L is adjusted to 2 mm; the thickness of the aluminum layer in the separator is 200 ⁇ m, the thickness of the PP encapsulation layer on one side is 50 ⁇ m, and the total thickness D of the separator is 0.3 mm.
  • Example 2-9 The difference between Example 2-9 and Example 2-6 is that the adjustment L is 1 mm.
  • the thickness h of the tab in the above table refers to the thickness h1 of the positive tab and the thickness h2 of the negative tab, that is, the thickness of the positive tab and the thickness of the negative tab are consistent.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Sealing Battery Cases Or Jackets (AREA)
  • Connection Of Batteries Or Terminals (AREA)

Abstract

本申请提供一种电化学装置及电子装置，电化学装置包括壳体、至少一个隔板以及至少两个电极组件。壳体包括第一壳体和第二壳体。隔板设于第一壳体与第二壳体之间。电化学装置于第一壳体与第二壳体之间设有至少两个腔体。电极组件包括极片组件以及至少两个与极片组件连接的极耳，极片组件收容于腔体。其中，电化学装置包括第一封印部，第一封印部包括第一封印边；沿第一封印部的厚度方向，位于第一封印部的各极耳之间于第一封印边处的最大距离为d，电化学装置的厚度为D，满足d≤0.4D。如此，能够提高电化学装置的封装可靠性。

Description

一种电化学装置及电子设备 技术领域
本申请涉及电池技术领域，特别是涉及一种电化学装置及电子设备。
背景技术
目前，电池广泛地运用于无人机、手机、平板、笔记本电脑等电子产品中。由于在某些应用场景下，单个电池单体并不能够实现期望的输出功率；因此，通常将多个电池单体相互串联、并联或混联，以使得该多个电池单体共同配合而实现期望功率的输出。然而，将多个电池单体串联、并联或混联虽然能够提高输出功率，但是整个电池组的能量密度却较低。因此，同袋串联/并联电池的设计被提出，同袋串联/并联电池包括壳体以及设置于同一壳体内的多个电极组件，串联的电极组件之间需通过隔离件分隔开以避免高电压下电解液的分解，并联的电极组件之间通过隔离件分隔开可以避免相互之间的干扰。
发明内容
本申请的发明人通过研究发现，当同袋串联/并联电池中，多个电极组件的极耳自壳体的同一侧封印边处伸出壳体时，该封印边的封装可靠性会存在不足，存在安全风险。
鉴于上述技术问题，本申请提供了一种电化学装置及电子装置，以提高同袋串联/并联电池的封装可靠性。
为解决上述技术问题，本申请第一方面：提供一种电化学装置，包括壳体、至少一个隔板以及至少两个电极组件。壳体包括第一壳体和第二壳体。隔板设于第一壳体与第二壳体之间，使电化学装置于第一壳体与第二壳体之间设有至少两个腔体。电极组件包括极片组件以及至少两个与极片组件连接的极耳，极片组件收容于腔体。其中，电化学装置包括第一封印部，第一封印部包括第一封印边；沿第一封印部的厚度方向，位于第一封印部的各极耳之间于第一封印边处的最大距离为d，电化学装置的厚度为D，满足：d≤0.4D。
通过满足d≤0.4D，能够提高第一封印部的表面平整度，降低由于极耳在第一封印部的厚度方向上的高度差值过大，导致壳体与隔板在第一封印部处封装时，由于局部欠压，导致封印强度较弱的风险，同时，壳体的侧壁能够为第一封印部欠压处的封装提供适当的应变，促进欠压处壳体与隔板之间的封装，从而提高封装的可靠性。
可选的，电化学装置满足以下条件中的至少一者：(1)d≤0.15D；(2)d≤2mm。满足该两条件中的至少一者时，可以进一步提高第一封印部位置的平整度，从而提高壳体与隔板在第一封印部处封装时，各处受压的均匀性，进而进一步提高第一封印部的封装可靠性。
可选的，至少一所述电极组件的至少两个极耳从所述壳体的第一侧端伸出，至少一所述电极组件的至少两个极耳从所述壳体的第二侧端伸出，所述第一侧端与所述第二侧端相邻或相对。由此，可以避免多个电极组件的多个极耳在壳体的同一侧而占用过多的空间，同时多个极耳分布在壳体的不同侧也能满足不同的连接需求。
可选的，至少一所述电极组件的至少两个极耳分别从所述壳体的第一侧端和第二侧端伸出。由此，通过该电极组件的两个极耳可方便的将至少两个极耳均从第一侧端或第二侧端伸出的电极组件串联连接起来。
可选的，所述隔板包括第一封装层、第二封装层以及中间层，所述中间层位于所述第一封装层与所述第二封装之间。
可选的，所述电极组件包括相邻的第一电极组件和第二电极组件，所述隔板包括位于所述第一电极组件与所述第二电极组件之间的第一隔板，所述第一电极组件的极耳包括第一极耳，所述第二电极组件的极耳包括与所述第一极耳相邻的第二极耳，沿着所述第一封印边的长度方向，所述第一极耳与所述第二极耳于所述第一封印边处的间距为L，所述第一隔板的厚度为T，L/T≥15。
一方面，第一极耳和第二极耳错位设置，相对于第一极耳和第二极 耳重叠设置，能够降低第一封印部的封印厚度差异，提高极耳处的封装可靠性；另一方面，通过满足上述关系，能够有效降低极耳之间隔板的弯折程度，使其受到的应力应变较小，且在极耳侧边拐角处的隔板在封印时能够更好的贴合与其连接的其他部件(如壳体)，在极耳受到外部应力拉扯隔板时，不容易剥离，从而进一步提高封装可靠性。
可选的，电化学装置满足以下条件中的至少一者：(1)所述第一极耳的厚度为h 1，L/h 1≥10；(2)所述第二极耳的厚度为h 2，L/h 2≥10；此时，能够进一步降低极耳之间隔板的弯折程度，使其受到的应力应变较小，并进一步改善隔板在第一极耳和/或第二极耳侧边拐角处与其他部件的贴合性，进而进一步提高封装可靠性。
可选的，电化学装置满足至少一者：(3)L/(h 1+T)≥5；(4)L/(h 2+T)≥5；(5)h 1≤0.2mm；(6)h 2≤0.2mm。此时，能够进一步降低极耳之间隔板的弯折程度，使其受到的应力应变较小，并进一步改善隔板在第一极耳和/或第二极耳侧边拐角处与其他部件的贴合性，进而进一步提高封装可靠性。
可选的，极片组件包括卷绕结构或叠片结构中的至少一种。
本申请第二方面，还提供了一种电子设备，包括上述的电化学装置。
本申请实施例的有益效果是：本申请提供的电化学装置，通过沿第一封印部的厚度方向，位于第一封印部的各极耳之间于所述第一封印边处的最大距离d，与电化学装置的厚度D，满足d≤0.4D。如此，能够提高第一封印部位置的平整度，降低由于极耳在第一封印部的厚度方向上的高度差值过大，导致壳体与隔板在第一封印部处封装时，由于局部欠压，导致封印强度较弱的风险，同时，壳体的侧壁能够为第一封印部欠压处的封装提供适当的应变，促进欠压处壳体与隔板之间的封装，从而提高第一封印部的封装可靠性。
附图说明
为了更清楚地说明本申请实施例的技术方案，下面将对本申请实施 例中所需要使用的附图作简单地介绍，显而易见地，下面所描述的附图仅仅是本申请的一些实施例，对于本领域普通技术人员来讲，还可以根据附图获得其他的附图。
图1是本申请其中一个实施例的电化学装置的结构示意图；
图2是图1中沿着直线MM'剖开后的示意图；
图3是一个实施例中极片组件为卷绕结构时的示意图；
图4是另一个实施例中极片组件为叠片结构时的示意图；
图5是图1中沿着XY平面剖切后的示意图；
图6是图1的前视图；
图7是图6的B部放大图；
图8是图7中部分结构的示意图；
图9是图1的右视图中电化学装置的部分结构示意图；
图10是另一实施例中多侧出极耳的电化学装置的结构示意图。
具体实施方式
为了便于理解本申请，下面结合附图和具体实施例，对本申请进行更详细的说明。需要说明的是，当元件被表述“固定于”另一个元件，它可以直接在另一个元件上、或者其间可以存在一个或多个居中的元件。当一个元件被表述“连接”另一个元件，它可以是直接连接到另一个元件、或者其间可以存在一个或多个居中的元件。本说明书所使用的术语“上”、“下”、“内”、“外”、“垂直的”、“水平的”等指示的方位或位置关系为基于附图所示的方位或位置关系，仅是为了便于描述本申请和简化描述，而不是指示或暗示所指的装置或元件必须具有特定的方位、以特定的方位构造和操作，因此不能理解为对本申请的限制。此外，术语“第一”、“第二”等仅用于描述目的，而不能理解为指示或暗示相对重要性。
除非另有定义，本说明书所使用的所有的技术和科学术语与属于本申请的技术领域的技术人员通常理解的含义相同。在本申请的说明书中所使用的术语只是为了描述具体的实施例的目的，不是用于限制本申请。本说明书所使用的术语“和/或”包括一个或多个相关的所列项目的任 意的和所有的组合。
此外，下面所描述的本申请不同实施例中所涉及的技术特征只要彼此之间未构成冲突就可以相互结合。
如图1-2所示，本申请其中一个实施例提供的电化学装置100，包括壳体10、电极组件20以及隔板30。壳体10包括第一壳体12和第二壳体14，壳体10用于限制出容纳电极组件20的封闭空间，隔板30位于第一壳体12与第二壳体14之间，隔板30用于分隔壳体10的内部空间，从而增加壳体10内部的独立腔体的数量。
电化学装置100可以包括一个隔板30，也可以包括多个隔板30，当电化学装置100包括一个隔板30时，一个隔板30可以将壳体10的内部空间分隔成两个独立的腔体。当电化学装置100包括多个隔板30，多个隔板30可以将壳体10的内部空间分隔成多个独立的腔体，例如，当电化学装置100具体包括两个隔板30时，两个隔板30可以将壳体10的内部空间分隔成三个独立的腔体；当电化学装置100包括三个隔板30时，三个隔板30将壳体10的内部空间分隔成四个独立的腔体。
为了便于描述，以下实施例以电化学装置100包括一个隔板30来进行举例说明。一个隔板30将壳体100的内部空间分隔成两个独立的腔体，分别称为第一腔体101以及第二腔体102。
电化学装置100可以包括两个电极组件20也可以包括三个以上数量的电极组件20。为了便于描述，以下实施例中，以电化学装置100包括两个电极组件20来进行举例说明，如图2所示，两个电极组件20分别为第一电极组件20a以及第二电极组件20b。当电化学装置100具有一个隔板30，且该隔板30分隔出两个独立的腔体时，第一电极组件20a设置于前述的第一腔体101，第二电极组件20b设置于前述的第二腔体102。第一电极组件20a、隔板30以及第二电极组件20b沿第一方向Z分布，第一方向Z与隔板30的厚度方向相同。
在一些实施例中，请结合图3，电极组件20包括极片组件21以及与极片组件21连接的极耳22，极耳22的数量至少有两个，至少两个极耳22之间的极性相异。在一些实施例中，极片组件21包括第一极片211、 第二极片212以及隔离膜213，隔离膜213设置于第一极片211与第二极片212之间，第一极片211与第二极片212的极性相反，隔离膜213用于降低第一极片211与第二极片212短路的风险。
在一些实施例中，如图1所示，电极组件20的多个极耳22，可以是均从壳体10的第一侧端伸出。如图10所示，电极组件20的多个极耳22也可以是自壳体10的不同侧端伸出，即一电极组件20的至少两个极耳22从壳体10的第一侧端伸出，另一电极组件20的至少两个极耳22从壳体的第二侧端伸出。在一些实施例中，壳体10的第一侧端与壳体10的第二侧端为相对设置的两端，在另一些实施例中，壳体10的第一侧端与壳体10的第二侧端为相邻的两端。
在一些实施例中，如图3所示，极片组件21可以是卷绕结构，即第一极片211、第二极片212以及隔离膜213叠置并且卷绕。在一些实施例中，如图4所示，极片组件21可以是叠片结构，此时第一极片211、第二极片212以及隔离膜213的数量均由多个，隔离膜213位于相邻的一个第一极片211与一个第二极片212之间，第一极片211、隔离膜213以及第二极片212沿着一方向堆叠设置，该方向为第一极片211、隔离膜213或第二极片212的厚度方向。
可以理解的，第一电极组件20a的极片组件与第二电极组件20b的极片组件的结构可以相同，即第一电极组件20a的极片组件与第二电极组件20b的极片组件都可以是卷绕结构，也可以是叠片结构。此外，第一电极组件20a的极片组件与第二电极组件20b的极片组件的结构也可以不同，即第一电极组件20a的极片组件以及电极组件20b的极片组件二者中一者为卷绕结构，另一者可以为卷绕结构。
为了便于描述，本实施例将第一电极组件20a的其中一个极耳称为第一极耳221。第一极耳221可以为正极极耳也可以为负极极耳。本实施例将第二电极组件20b的其中一个极耳称为第二极耳222，第二极耳222可以为正极极耳也可以为负极极耳。第一极耳221以及第二极耳222的极性可以相同也可以不同。第一极耳221与第二极耳222可以相互电连接，也可以不相互连接。
如图5所示，隔板30包括第一封印区31，电化学装置100进行封装时，隔板30位于所述第一封印区31的部分与其它部件进行封印。也即，隔板30在第一封印区31的部分与其它部件进行固定连接(可以是热熔连接或粘结)。当电化学装置100仅具有一个隔板30时，隔板30的第一封印区31的两侧壁面均与壳体10连接。当电化学装置100具有两个隔板30时，其中一个隔板30的第一封印区31的一侧壁面与另一个隔板30连接、另一侧壁面与壳体10连接。当隔板30的数量为三个或三个以上时，位于中间的隔板30的第一封印区31的两侧壁面均与位于该隔板30两侧的其他隔板30连接。
第一封印区31可以呈“回”字形，且第一封印区31可以延伸至隔板30的外侧边沿位置，第一封印区31也可以与隔板30的外侧边沿间隔一定距离。
在一些实施例中，隔板30包括第一封装层、第二封装层以及中间层，中间层位于第一封装层以及第二封装层之间。在一些实施例中，第一封装层以及第二封装层均采用可热熔的材料制成，例如PP材料。
在一些实施例中，请再次参阅图1，电化学装置100包括第一封印部103，第一封印部103处壳体10与隔板30进行封印，也即，第一封印部103处壳体10与隔板30进行固定连接(可以是热熔连接或粘结)。其中，第一封印部103包括第一封印边1031，第一封印边1031为第一封印部103远离壳体10的腔体空间的一边。在一些实施例中，第一封印部103可以呈“回”字形，即壳体10的四周边均用于与隔板连接固定，此时壳体10为可相对分离的两部分。此外，第一封印部103也可以是呈“凹”字形，即壳体10为一体连接的两部分，且每部分上均具有内凹的腔体空间，该两部分可相互扣合，且与隔板连接固定。在本实施例中，壳体10为可相对分离两部分固定连接形成。
在一些实施例中，请结合图6至图8，沿着第一封印部103的厚度方向，即沿着第一方向Z，位于第一封印部103的各所述极耳22之间于第一封印边1031处的最大距离为d，电化学装置的厚度为D，满足d≤0.4D。其中，最大距离d为两个极耳沿着第一封印部103的厚度方向， 相距最远的两个表面之间的距离。在本实施例中，第一极耳221以及第二极耳222均于第一封印边1031处延伸出壳体10。当隔板30的数量仅有一个时，沿着第一封印部103的厚度方向，位于第一封印部的各所述极耳22之间于第一封印边1031处的最大距离，可以是第一封印边1031处，第一极耳221与第二极耳222在第一封印部103的厚度方向上的距离。示例性的，d/D可以为0.1、0.2、0.3或0.4等。一种具体的举例中，当D为3.3mm时，d≤1.32mm。
本申请的发明人发现，由于第一极耳221以及第二极耳222有部分自第一封印部103伸出壳体10外以用于与外部进行连接，第一极耳221以及第二极耳222中位于第一封印部103的区域具有厚度，会影响到第一封印部103的封装效果。而且，不同腔体的多个电极组件的极耳均至少有部分极耳需伸出壳体10外，多个极耳的厚度不断累加，更加影响到第一封印部103封印的可靠性。本申请的发明人通过研究发现，当沿着第一封印部103的厚度方向，第一极耳221与第二极耳222之间于第一封印边1031处的最大距离d满足d≤0.4D时，能够使得第一封印部103具有较高的封装可靠性。这是由于，满足以上关系，有利于第一封印部103封装平面的平整度合适，同时，壳体10的侧壁能够为第一封印部103欠压处的封装提供适当的应变，促进欠压处壳体10与隔板30之间的封装，从而提高第一封印部103的封装可靠性。
在一些实施例中，满足以下关系式中的至少一者：(1)d≤0.15D；(2)d≤2mm。当满足以上关系式中至少一者时，可以进一步提高第一封印部表面的平整度，从而提高壳体与隔板在第一封印部处封装时，各处受压的均匀性，进而进一步提高第一封印部103的封装可靠性。
在一些实施例中，请参阅图7，第一极耳221以及第二极耳222均由第一封印边1031延伸出壳体10。隔板30的厚度为T，即沿图7中的第一方向Z,隔板30的厚度为T。如图9所示，沿第一封印边1031的长度方向，即第二方向Y，第一极耳221与第二极耳222于第一封印边1031处的最小间距为L,且L/T≥15。示例性地，L/T可以为15、20、25、30或100等。一种具体的举例中，当T为0.2㎜时，L≥3㎜。
本申请的发明人发现，由于第一极耳221以及第二极耳222位于隔板30的两侧，故一方面，极耳的设置方式会对封装可靠性造成较大影响，相对于第一极耳221和第二极耳222重叠设置，第一极耳221和第二极耳222错位设置，能够降低第一封印部103处的封印厚度差异，提高极耳处的封装可靠性；另一方面，当第一极耳221和第二极耳222错位设置时，沿第一封印边1031的长度方向，隔板30位于第一极耳221以及第二极耳222之间的部分存在弯折，该处的封装可靠性受到影响。本申请的发明人通过研究发现，当第一极耳221与第二极耳222于第一封印边1031处的最小间距L与隔板30的厚度T满足L/T≥15时，能够使得电化学装置100具有较高的封装可靠性。这是由于，满足上述关系，能够有效降低极耳之间隔板30的弯折程度，使其受到的应力应变较小，且隔板30在第一极耳221与第二极耳222之间的部分在封印时能够更好的贴合与其连接的其他部件，在极耳受到外部应力拉扯隔板时，不容易剥离，从而进一步提高封装可靠性。
本申请的发明人还发现，第一极耳221以及第二极耳222沿第一方向Z的厚度尺寸与第一极耳221以及第二极耳222沿第二方向Y的间距之间满足特定关系可以进一步改善隔板30在第一极耳221与第二极耳222之间的部分在封印时与其他部件的贴合性。鉴于此，参见图6-8，一种实施例中，可以使电化学装置100满足以下关系中的至少一者：(3)第一极耳221的厚度为h 1，L/h 1≥10；(4)第二极耳222的厚度为h 2，L/h 2≥10。此时，能够进一步降低隔板30位于第一极耳221以及第二极耳222之间部分的弯折程度，使其受到的应力应变较小，并进一步改善隔板30在第一极耳221与第二极耳222之间的部分与其他部件的贴合性，进而进一步提高封装可靠性。
换句话说，一种实施例中，可以在L/T≥15的前提下，还使L/h 1≥10。或另一种实施例中，在L/T≥15的前提下，还使L/h 2≥10。或又一种实施例中，在L/T≥15的前提下，还使L/h 1≥10、L/h 2≥10。
一种具体的举例中，当隔板30的厚度T为0.2㎜、h 1为0.1㎜、h 2为0.1㎜时，L/T≥15条件下，L最小值取3㎜；L/h 1≥10条件下，L最小 值取1㎜；L/h 2≥10条件下，L最小值取1㎜，综合得出，L最终最小值取3㎜。当采用L/h 1≥10和/或L/h 2≥10来限定第一极耳221与第二极耳222沿第二方向Y的距离时，能够进一步保证电化学装置100的封装可靠性。
一种实施例中，电化学装置100还可以满足以下特征中的至少一者：(5)L/(h 1+T)≥5；(6)L/(h 2+T)≥5；此时，能够进一步降低隔板30位于第一极耳221以及第二极耳222之间部分的弯折程度，使其受到的应力应变较小，并进一步改善隔板在第一极耳221与第二极耳222之间的部分与其他部件的贴合性，进而进一步提高封装可靠性。
一种实施例中，h 1≤0.2㎜；和/或h 2≤0.2㎜。
一种具体的举例中，电化学装置100同时满足条件(5)、(6)。示例性地，当T为0.2㎜、h 1为0.2㎜、h 2为0.2㎜时，L/T≥15条件下，L最小值取3㎜；L/(h 1+T)≥5条件下，L最小值取2㎜；L/(h 2+T)≥5条件下，L最小值取2㎜。综合得出，L最终最小值取3㎜。
进一步的实施例中，L≥3㎜；和/或T≤0.3㎜。当T≤0.3㎜时，能够使隔板30的厚度不会过大，减少隔板30占用电化学装置100过多的空间，从而降低电化学装置10的能量密度。
本申请还提供了一种电子装置200，其包含本申请提供的电化学装置100。本申请的电子装置200没有特别限定，其可以是现有技术中已知的任何电子装置。例如，电子装置200包括但不限于笔记本电脑、笔输入型计算机、移动电脑、电子书播放器、便携式电话、便携式传真机、便携式复印机、便携式打印机、头戴式立体声耳机、录像机、液晶电视、手提式清洁器、便携CD机、迷你光盘、收发机、电子记事本、计算器、存储卡、便携式录音机、收音机、备用电源、电机、汽车、摩托车、助力自行车、自行车、照明器具、玩具、游戏机、钟表、电动工具、闪光灯、照相机、家庭用大型蓄电池和锂离子电容器等。
制备本申请的电化学装置的方法没有特别限制，可以采用本领域公知的任何方法，例如，在一实施方式中，本申请可以采用如下制备方法制备：
(1)负极极片的制备：将负极活性材料、粘结剂和溶剂调配成浆料，并搅拌均匀。将浆料均匀涂覆在负极集流体上并烘干，得到单面涂覆的负极极片。在负极集流体的另一个表面上重复以上步骤，得到双面涂覆的负极极片。然后，经冷压、裁切后待用。
(2)正极极片的制备：将正极活性材料、粘结剂、导电剂和溶剂调配成浆料，并搅拌均匀。将浆料均匀涂覆在正极集流体上并烘干，得到单面涂覆的正极极片。在正极集流体的另一个表面上重复以上步骤，得到双面涂覆的正极极片。然后，经冷压、裁切后待用。
(3)电解液的制备：将锂盐和非水溶剂混合并搅拌均匀，得到电解液。
(4)电极组件的制备：电极组件的结构可以是卷绕结构或叠片结构，其中，将多个负极极片、隔膜、正极极片依次堆叠并固定可形成叠片结构的电极组件；将负极极片、隔膜、正极极片依次堆叠后并卷绕可形成卷绕结构的电极组件；每个电极组件包含一个正极极耳和一个负极极耳；重复上述步骤则可得到多个电极组件。
(5)隔板：可以采用本领域公知的任何隔板。
(6)电极组件组装：将包装壳置于组装夹具内，然后将电极组件与隔板间隔设置，并将电极组件的所有极耳引出包装壳外，以备后续加工，最后进行顶封和侧封，并留下注液口。
(7)注液封装：分别给多个腔体注入电解液，经热压、化成、脱气后密封。
(8)串联连接：将一个电极组件的正极极耳和另一个电极组件的负极极耳通过激光焊的方式焊接连接在一起，实现串联连接，即得到最终的电化学装置。
本申请提供的电化学装置中可以包含两个电极组件，也可以包含三个以上电极组件。含有两个电极组件或三个以上电极组件的电化学装置的制备方法均可参照上述电化学装置的制备方法。
本申请中所用的术语一般为本领域技术人员常用的术语，如果与常用术语不一致，以本申请中的术语为准。
实施例1-1
锂离子电池的制备
(1)负极极片的制备：将负极活性材料人造石墨、导电炭黑(Super P)、丁苯橡胶(SBR)按照重量比96:1.5:2.5进行混合，加入去离子水，调配成固含量为70wt％的浆料，并搅拌均匀。将浆料均匀涂覆在负极集流体铜箔的一个表面上，烘干，得到单面涂覆有负极活性材料层的负极极片。在负极集流体铜箔的另一个表面上重复以上步骤，得到双面涂覆有负极活性材料层的负极极片。冷压后，将负极极片裁切成41mm×61mm的规格待用。
(2)正极极片的制备：将正极活性材料钴酸锂(LiCoO 2)、导电炭黑(Super P)、聚偏二氟乙烯(PVDF)按照重量比97.5:1.0:1.5进行混合，加入N-甲基吡咯烷酮(NMP)，调配成固含量为75wt％的浆料，并搅拌均匀。将浆料均匀涂覆在正极集流体铝箔的一个表面上，烘干，得到单面涂覆有正极活性材料层的正极极片。在正极集流体铝箔的另一个表面上，重复以上步骤，得到双面涂覆有正极活性材料层的正极极片。冷压后，将正极极片裁切成38mm×58mm的规格待用。
(3)电解液的制备：在干燥氩气气氛中，首先将有机溶剂碳酸乙烯酯(EC)、碳酸甲乙酯(EMC)和碳酸二乙酯(DEC)以质量比EC:EMC:DEC＝30:50:20混合，然后向有机溶剂中加入锂盐六氟磷酸锂(LiPF 6)溶解并混合均匀，得到基于电解液的质量，LiPF 6浓度为12.5％的电解液。
(4)第一电极组件和第二电极组件的制备：将隔膜、负极极片、隔膜、正极极片依次层叠设置组成叠片结构，然后将整个叠片结构的四个角固定好以备用。每个电极组件包含一个正极极耳和一个负极极耳，正极极耳为铝(Al)，负极极耳为镍(Ni)，两个极耳并排设置，正负极极耳的厚度h均为0.2mm，极耳的宽度为5mm；隔膜选用厚度为15μm的聚乙烯(PE)膜。
(5)隔板的制备：将封装层材料聚丙烯(PP，熔点为140℃)均匀分散到分散剂N-甲基吡咯烷酮(NMP)中，制备得到PP悬浊液；利用 涂胶机，在厚度为50μm铝层两侧分别涂覆PP悬浊液；然后在130℃进行烘干处理，其中，铝层单侧PP封装层的厚度为25μm，隔板总厚度T为100μm。
(6)电极组件组装：将冲坑成型的铝塑膜(厚度为150μm)置于组装夹具内，坑面朝上，将第一电极组件置于坑内，并在铝塑膜的边缘处第一电极组件的极耳对应的区域设置极耳胶，然后将隔板放置于第一电极组件上，使得边沿对齐，施加外力压紧得到组装半成品。将组装半成品置于组装夹具内，隔板一面朝上，将第二电极组件放置于隔板上，使得边沿对齐，施加外力压紧，然后将另一个冲坑成型的铝塑膜坑面朝下覆盖于第二电极组件上，并在铝塑膜的边缘处第二电极组件的极耳对应的区域设置极耳胶。将第一电极组件和第二电极组件的正负极极耳均引出铝塑膜外，采用热压的方式进行顶封和侧封，得到组装电极组件。其中，第一电极组件的负极极耳和第二电极组件的正极极耳之间的间距L为5mm。
(7)注液封装：分别给每个腔体注入电解液，经热压、化成、脱气后密封。
(8)串联连接：将第一电极组件的负极极耳和第二电极组件的正极极耳通过激光焊的方式焊接连接在一起，实现串联连接，锂离子电池组装完成。其中，锂离子电池的厚度D为2.5mm；同侧极耳高度差d为1mm。
实施例1-2
与实施例1-1的区别在于，锂离子电池的厚度D为3.3mm。
实施例1-3
与实施例1-1的区别在于，隔板中铝层的厚度为20μm，铝层单侧PP封装层的厚度为15μm，隔板总厚度T为50μm；锂离子电池的厚度D为3.3mm；同侧极耳高度差d为0.66mm。
实施例1-4
与实施例1-3的区别在于，锂离子电池的厚度D为10mm；同侧极耳高度差d为0.5mm。
实施例1-5
与实施例1-1的区别在于，同侧极耳高度差d为0.6mm。
实施例1-6
与实施例1-1的区别在于，锂离子电池的厚度D为3.3mm；同侧极耳高度差d为0.6mm。
实施例1-7
与实施例1-3的区别在于，同侧极耳高度差d为0.5mm。
实施例1-8
与实施例1-3的区别在于，锂离子电池的厚度D为6mm；同侧极耳高度差d为0.6mm。
实施例1-9
与实施例1-3的区别在于，锂离子电池的厚度D为10mm；同侧极耳高度差d为1.0mm。
实施例1-10
与实施例1-1的区别在于，锂离子电池的厚度D为10mm。
实施例1-11
与实施例1-1的区别在于，隔板中铝层的厚度为100μm，铝层单侧PP封装层的厚度为25μm，隔板总厚度T为150μm；锂离子电池的厚度D为10mm；同侧极耳高度差d为2mm。
对比例1-1
与实施例1-1的区别在于，锂离子电池的厚度D为4mm；同侧极耳高度差d为2mm。
测试方法：
封装可靠性测试：
在顶封位置(极耳伸出侧)的非极耳区域裁切宽度为8mm的封装区域试样，采用多功能拉力测试仪，夹具夹持封装区域一侧的壳体和隔板，拉伸速度取50mm/min，进行测试，得到剥离力P 1，则封装强度F＝P 1/8mm。
表1不同极耳高度差d、锂离子电池厚度D的封装强度测试
Figure PCTCN2022084560-appb-000001
由表1的实施例1-1至1-11与对比例1-1的比较可知，当d≤0.4D时，锂离子电池的非极耳区具有显著提升的封装强度。可能的原因在于，当满足d≤0.4D时，能够提高封印部的表面平整度，降低由于极耳在封印部的厚度方向上的高度差值过大，导致壳体与隔板在封印部处封装时，由于非极耳区局部欠压，导致封装强度较弱的风险，同时，d≤0.4D时，壳体的侧壁能够为封印部欠压处的封装提供适当的应变，促进欠压处壳体与隔板之间的封装，从而提高了封装的可靠性。
实施例2-1
与实施例1-11的区别在于，隔板中铝层的厚度为100μm，铝层单侧PP封装层的厚度为50μm，隔板总厚度T为0.2mm。
实施例2-2与实施例2-1的区别在于，调整L为3mm；h为0.1mm。
实施例2-3与实施例2-1的区别在于，调整L为4mm；隔板中铝层厚度为50μm，单层PP封装层的厚度为25μm，隔板总厚度T为0.1mm；h为0.3mm。
实施例2-4与实施例2-1的区别在于，调整L为4mm；h为0.3mm。
实施例2-5与实施例2-3的区别在于，调整L为10mm；h为0.1mm。
实施例2-6与实施例2-3的区别在于，调整L为3mm；h为0.2mm。
实施例2-7与实施例2-1的区别在于，调整第一电极组件的负极极耳和第二电极组件的正极极耳重叠引出，即L为0mm。
实施例2-8与实施例2-1的区别在于，调整L为2mm；隔板中铝层厚度为200μm，单侧PP封装层的厚度为50μm，隔板总厚度D为0.3mm。
实施例2-9与实施例2-6的区别在于，调整L为1mm。
弯折稳定性测试：
将连接的两个极耳进行360°弯折测试，即极耳以隔板与包装壳的顶封封印区为轴，先向电化学装置的一侧Y-Z面(Y-Z面如图1所示)进行弯折，直至连接极耳与Y-Z面贴合，记为一次弯折。然后反向弯折360°，与电化学装置另一侧Y-Z面贴合，记为二次弯折。如此反复，直至两极耳之间的封印外边缘处出现裂痕，记录此时对应的极耳弯折次数。
表2实施例2-1至2-6、对比例2-1至2-3弯折稳定性测试结果
Figure PCTCN2022084560-appb-000002
上表中的极耳厚度h是指正极耳的厚度h1以及负极耳的厚度h2，即正极耳的厚度以及负极耳的厚度保持一致。
通过表2中的实施例2-1至2-6和实施例2-7至2-9的比较可以看出，当L/T≥15时，所获得的锂离子电池具有更优的弯折稳定性。这是由于，一方面，第一极耳和第二极耳错位设置，相对于第一极耳和第二极耳重叠设置的实施例2-7，能够降低顶封处的封印厚度差异，提高极耳处的封装可靠性；另一方面，通过满足上述关系，能够有效降低极耳之间隔板的弯折程度，使其受到的应力应变较小，且在极耳侧边拐角处的隔板在封印时能够更好的贴合与其连接的其他部件，在极耳受到外部应力拉扯隔板时，不容易剥离，从而进一步提高封装可靠性。
需要说明的是，本申请的说明书及其附图中给出了本申请的较佳的实施例，但是，本申请可以通过许多不同的形式来实现，并不限于本说明书所描述的实施例，这些实施例不作为对本申请内容的额外限制，提供这些实施例的目的是使对本申请的公开内容的理解更加透彻全面。并且，上述各技术特征继续相互组合，形成未在上面列举的各种实施例，均视为本申请说明书记载的范围；进一步地，对本领域普通技术人员来说，可以根据上述说明加以改进或变换，而所有这些改进和变换都应属于本申请所附权利要求的保护范围。

Claims (10)

  1. 一种电化学装置，其特征在于，包括：
    壳体，包括第一壳体和第二壳体；
    至少一个隔板，所述隔板设于所述第一壳体与所述第二壳体之间；使所述电化学装置于所述第一壳体与所述第二壳体之间设有至少两个腔体；
    至少两个电极组件，每个电极组件包括极片组件以及至少两个与所述极片组件连接的极耳，每个极片组件分别收容于一个所述腔体中；
    其中，所述电化学装置包括第一封印部，所述第一封印部包括第一封印边；沿所述第一封印部的厚度方向，位于所述第一封印部的各所述极耳之间于所述第一封印边处的最大距离为d，所述电化学装置的厚度为D，满足：d≤0.4D。
  2. 根据权利要求1所述的电化学装置，其特征在于，满足以下特征中的至少一者：
    (i)d≤0.15D；
    (ii)d≤2mm。
  3. 根据权利要求1所述的电化学装置，其特征在于，至少一所述电极组件的至少两个极耳从所述壳体的第一侧端伸出，至少一所述电极组件的至少两个极耳从所述壳体的第二侧端伸出，所述第一侧端与所述第二侧端相邻或相对。
  4. 根据权利要求3所述的电化学装置，其特征在于，至少一所述电极组件的至少两个极耳分别从所述壳体的第一侧端和第二侧端伸出。
  5. 根据权利要求1所述的电化学装置，其特征在于，所述隔板包括第一封装层、第二封装层以及中间层，所述中间层位于所述第一封装层与所述第二封装之间。
  6. 根据权利要求1所述的电化学装置，其特征在于，所述电极组件包括相邻的第一电极组件和第二电极组件，所述隔板包括位于所述第一电极组件与所述第二电极组件之间的第一隔板，所述第一电极组件的极耳包括第一极耳，所述第二电极组件的极耳包括与所述第一极耳相邻的第二极耳，沿着所述第一封印边的长度方向，所述第一极耳与所述第二极耳于所述第一封印边处的间距为L，所述第一隔板的厚度为T，L/T≥15。
  7. 根据权利要求6所述的电化学装置，其特征在于，满足以下特征中的至少一者：
    (1)所述第一极耳的厚度为h 1，L/h 1≥10；
    (2)所述第二极耳的厚度为h 2，L/h 2≥10。
  8. 根据权利要求7所述的电化学装置，其特征在于，满足以下特征中的至少一者：
    (3)L/(h 1+T)≥5；
    (4)L/(h 2+T)≥5；
    (5)h 1≤0.2mm；
    (6)h 2≤0.2mm。
  9. 根据权利要求1-8任意一项所述的电化学装置，其特征在于，所述极片组件包括卷绕结构或叠片结构中的至少一种。
  10. 一种电子设备，其特征在于，包括如权利要求1-9中任意一项所述的电化学装置。
PCT/CN2022/084560 2022-03-31 2022-03-31 一种电化学装置及电子设备 WO2023184400A1 (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/CN2022/084560 WO2023184400A1 (zh) 2022-03-31 2022-03-31 一种电化学装置及电子设备
CN202280010285.XA CN116830371A (zh) 2022-03-31 2022-03-31 一种电化学装置及电子设备

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2022/084560 WO2023184400A1 (zh) 2022-03-31 2022-03-31 一种电化学装置及电子设备

Publications (1)

Publication Number Publication Date
WO2023184400A1 true WO2023184400A1 (zh) 2023-10-05

Family

ID=88117090

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/084560 WO2023184400A1 (zh) 2022-03-31 2022-03-31 一种电化学装置及电子设备

Country Status (2)

Country Link
CN (1) CN116830371A (zh)
WO (1) WO2023184400A1 (zh)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004071178A (ja) * 2002-08-01 2004-03-04 Nissan Motor Co Ltd 電池集合体
CN112002868A (zh) * 2020-09-08 2020-11-27 宁德新能源科技有限公司 一种电化学装置及电子装置
CN113471631A (zh) * 2021-07-05 2021-10-01 宁德新能源科技有限公司 电化学装置及包含该电化学装置的电子装置
CN113921993A (zh) * 2021-09-30 2022-01-11 宁德新能源科技有限公司 一种电化学装置及包含该电化学装置的电子装置

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004071178A (ja) * 2002-08-01 2004-03-04 Nissan Motor Co Ltd 電池集合体
CN112002868A (zh) * 2020-09-08 2020-11-27 宁德新能源科技有限公司 一种电化学装置及电子装置
CN114156607A (zh) * 2020-09-08 2022-03-08 宁德新能源科技有限公司 一种电化学装置及电子装置
CN113471631A (zh) * 2021-07-05 2021-10-01 宁德新能源科技有限公司 电化学装置及包含该电化学装置的电子装置
CN113921993A (zh) * 2021-09-30 2022-01-11 宁德新能源科技有限公司 一种电化学装置及包含该电化学装置的电子装置

Also Published As

Publication number Publication date
CN116830371A (zh) 2023-09-29

Similar Documents

Publication Publication Date Title
EP4109617A2 (en) Electrochemical apparatus and electronic apparatus
WO2022267925A1 (zh) 电化学装置和电子装置
CN112002868B (zh) 一种电化学装置及电子装置
JP2017532715A (ja) ２つ以上のケース部材を含む角型電池セル
JP2003051339A (ja) 非水電解質電池およびその製造方法
CN1221054C (zh) 袋式锂离子电池的制备方法
JP2013080563A (ja) 積層型二次電池
CN102856577A (zh) 非水电解质二次电池
CN202094228U (zh) 一种带鼓包修复装置的软包装锂离子电池
JP2012248381A (ja) 電池
WO2023004833A1 (zh) 电池单体、电池、用电装置及制备电池单体的方法和设备
CN114614190A (zh) 一种电化学装置及电子设备
WO2022205192A1 (zh) 电化学装置以及电子装置
JP2013033688A (ja) 二次電池
WO2024078295A1 (zh) 电化学装置和电子装置
US20230246272A1 (en) Electrochemical apparatus and electronic apparatus
WO2023184400A1 (zh) 一种电化学装置及电子设备
WO2022170998A1 (zh) 一种电池和电子设备
CN215184263U (zh) 电池组及电子装置
CN201673968U (zh) 非对称组装结构的微型聚合物锂离子电池
JP2013033687A (ja) 蓄電池モジュール
CN114730905A (zh) 一种电化学装置及包含该电化学装置的电子装置
WO2023197160A1 (zh) 一种电化学装置及电子设备
CN201741762U (zh) 一种大容量高功率锂离子电池
CN202695643U (zh) 一种锂离子电池卷芯结构电芯及其锂离子电池

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 202280010285.X

Country of ref document: CN

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22934238

Country of ref document: EP

Kind code of ref document: A1