Prismatic batteries and electrical devices containing prismatic batteries

Abstract

A prismatic battery and an electric device including an electrode assembly. The electrode assembly includes a configuration in which a positive electrode piece, a separator, and a negative electrode piece are stacked and wound. The positive electrode piece includes a positive electrode current collector, and an active material layer, an insulating layer, and an uncoated area are provided on a first surface of the positive electrode current collector, and the active material layer, the insulating layer, and the uncoated area are arranged in order along the axial direction of the prismatic battery. The electrode assembly further includes a flattened portion, and the flattened portion has a flattened surface formed by folding the uncoated area toward the winding central axis of the electrode assembly and overlapping them. The insulating layer plays a role in supporting the positive electrode current collector and prevents a short circuit caused by the flattened portion folding back and contacting the negative electrode piece beyond the separator.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This invention claims priority to a Chinese patent application filed with the China Patent Office on November 4, 2022, bearing application number 202211379212.6 and titled "Prism battery and electrical device containing prism battery", the entire contents of which are incorporated herein by reference. [Technical field]

[0002] The present invention relates to the field of energy storage devices, in particular prismatic batteries and electrical devices including prismatic batteries. [Background technology]

[0003] In the manufacturing process of a full-tab battery (e.g., a cylindrical battery), it is necessary to carry out a tab flattening process. The tab flattening process involves bending the tabs that are normally upright so that they come into contact with each other to achieve better current collection. At the same time, the flattened tabs are in the same plane, which is convenient for the subsequent current collector welding process. However, in a conventional full-tab battery, after flattening, the positive electrode tab is easily folded back and comes into contact with the negative electrode active material layer, resulting in a short circuit. Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a prismatic battery capable of reducing the risk of short circuit and an electric device including the prismatic battery. [Means for solving the problem]

[0005] A first aspect of the present invention provides a prismatic battery including an electrode assembly. The electrode assembly includes a configuration in which a positive electrode piece, a separator, and a negative electrode piece are stacked and wound. The positive electrode piece includes a positive electrode current collector, and an active material layer, an insulating layer, and an uncoated area are provided on a first surface of the positive electrode current collector, and the active material layer, the insulating layer, and the uncoated area are arranged in order along the axial direction of the prismatic battery. The electrode assembly further includes a planarizing portion, and the planarizing portion has a planarizing surface formed by folding the uncoated area toward the central axis of the winding of the electrode assembly and overlapping them.

[0006] The prismatic battery provided by the present invention has an insulating layer to improve the hardness of the positive electrode current collector at the portion where the insulating layer is located, and the insulating layer serves to support the corresponding portion of the positive electrode current collector and prevent a short circuit caused by the flattened portion folding back and passing over the separator to contact the negative electrode piece.

[0007] According to some embodiments of the present invention, the height L of the flattened portion is 0.2 to 4 mm along the axial direction of the prismatic battery. If the height L of the flattened portion is less than 0.2 mm, the insulating layer may be damaged by being significantly compressed by the laminated region of the flattened portion, and therefore cannot adequately support and protect the positive electrode current collector. If the height L of the flattened portion exceeds 4 mm, the flattening amount of the non-coated region is too small, and the flattened non-coated region (flattened portion) is likely to bounce back.

[0008] According to some embodiments of the present invention, the height W of the insulating layer is 1-5 mm along the axial direction of the prismatic battery. If the height W of the insulating layer is less than 1 mm, the insulating layer is too narrow (too small in height), and the coating capacity of the coating process may be unstable, causing the insulating layer to be left uncoated, so that the insulating layer cannot play a good role in supporting and protecting the positive electrode current collector during flattening. The greater the height W of the insulating layer, the greater the loss of energy density of the prismatic battery.

[0009] According to some embodiments of the present invention, the height W of the insulating layer is 1.5 to 5 mm. In this way, it is possible to ensure the stability of the process capacity for coating the insulating layer, and further ensure sufficient support strength of the insulating layer for the positive electrode current collector.

[0010] According to some embodiments of the present invention, when the thickness of the insulating layer is h and the thickness of the active material layer is H, h and H satisfy 0.1H≦h≦H. If h<0.1H, the insulating layer is too thin, which may cause coating leakage due to unstable process capacity of the coating process, and the insulating layer cannot play a good role in supporting and protecting the positive current collector during planarization.

[0011] According to some embodiments of the present invention, h and H satisfy 0.2H≦h≦0.9H. In this way, the process capacity of coating the insulating layer can be ensured and sufficient support strength of the insulating layer for the positive electrode current collector can be further ensured. If h>0.9H, the insulating layer is too thick, and in this case, the insulating layer has a certain hardness and brittleness, so if it is too thick, it may burst due to flattening stress, and cannot play a good role in supporting and protecting the positive electrode current collector.

[0012] According to some embodiments of the present invention, H is between 50 and 100 μm.

[0013] According to some embodiments of the present invention, the positive electrode current collector further has a second surface located opposite the first surface, and the active material layer, the insulating layer and the uncoated region are also provided on the second surface.

[0014] According to some embodiments of the present invention, the insulating layer includes inorganic particles, the inorganic particles including at least one of aluminum oxide, zinc oxide, calcium oxide, silicon oxide, zirconium oxide, magnesium oxide, titanium oxide, hafnium dioxide, tin oxide, cerium dioxide, nickel oxide, yttrium oxide, silicon carbide, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, barium sulfate, and boehmite.

[0015] A second aspect of the present invention provides an electrical device including the above-described prismatic battery. [Brief description of the drawings]

[0016] The above and / or additional aspects and advantages of the present invention will become more apparent and easier to understand by referring to the following detailed description of the preferred embodiments, taken in conjunction with the drawings, in which: FIG. [Figure 1] FIG. 1 is a schematic diagram of a prismatic battery provided by one embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view taken along line II-II of the prismatic battery shown in FIG. [Diagram 3] FIG. 3 is a schematic diagram of an electrode assembly according to one embodiment of the present invention after deployment. [Figure 4] FIG. 4 is a schematic cross-sectional view of a positive electrode piece provided by an embodiment of the present invention. [Diagram 5] FIG. 5 is a schematic cross-sectional view of a positive electrode piece according to another embodiment of the present invention. [Explanation of symbols]

[0017] Pillar battery 100 Electrode Assembly 10 Positive electrode piece 20 Negative electrode piece 30 Separator 40 Positive electrode current collector 21 Active material layer 22 Insulating layer 23 1st surface 21a 2nd surface 21b Uncoated area 24, 31a Flattening section 101 Flattened surface 102 First end 211 Second end 212 Negative electrode current collector 31 Negative electrode active material layer 32 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The technical solutions in the embodiments of the present invention will be described below in detail and clearly. Obviously, the described embodiments are only some of the embodiments of the present invention, and not all of the embodiments. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for describing specific embodiments, and are not intended to limit the present invention.

[0019] Hereinafter, the embodiments of the present invention will be described in detail. However, the present invention can be embodied in many different forms and should not be construed as being limited to the exemplary embodiments described herein. Rather, these exemplary embodiments are provided to provide a thorough and detailed description of the contents of the present invention to those skilled in the art.

[0020] Also, for brevity and clarity, the sizes or thicknesses of various components, layers may be exaggerated in the drawings. Like numbers refer to like elements throughout the specification. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It should be understood that when element A is referred to as "connected" to element B, element A may be directly connected to element B, or there may be an intermediate element C such that element A and element B are indirectly connected to each other.

[0021] Furthermore, when used in describing embodiments of the present invention, "may" means "one or more embodiments of the present invention."

[0022] The terminology used herein is for the purpose of describing particular embodiments and is not intended to limit the present invention. As used herein, the singular form is intended to include the plural form unless otherwise specified in the specification. Furthermore, the term "comprises" as used herein refers to the presence of a stated feature, value, step, operation, element, and / or component, but is to be understood as not excluding the presence or addition of one or more other features, values, steps, operations, elements, components, and / or combinations thereof.

[0023] As used herein, spatial terms such as "above" are intended to describe the relationship of one element or feature to another element(s) or feature(s) shown in the drawings for ease of description. In addition to the orientations shown in the drawings, spatial terms should be understood to be intended to include different orientations of a device or apparatus in use or operation. For example, if the device in the drawings is inverted, an element described as "above" or "on" another element or feature would change to being "below" or "below" the other element or feature. Thus, the exemplary term "above" can include an orientation of above and below. As used herein, terms such as first, second, third, etc. may be used to describe various elements, components, regions, layers, and / or portions, but it should be understood that these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Thus, a first element, component, region, layer or section described below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

[0024] 1 and 2, one embodiment of the present invention provides a prismatic battery 100 including an electrode assembly 10 and a case (not shown). The case is generally cylindrical, such as a cylindrical, elliptical, or rectangular column. The electrode assembly 10 is housed in the case and has a shape that fits the case, such as a cylindrical, elliptical, or rectangular column. The case is made of a conductive material, such as a metal material. The electrode assembly 10 includes a positive electrode piece 20, a negative electrode piece 30, and a separator 40 disposed between the positive electrode piece 20 and the negative electrode piece 30. The electrode assembly 10 includes a configuration in which the positive electrode piece 20, the separator 40, and the negative electrode piece 30 are stacked and wound. That is, the electrode assembly 10 is formed by stacking the positive electrode piece 20, the separator 40, and the negative electrode piece 30 in order and winding them.

[0025] 2 and 4, the positive electrode piece 20 includes a positive electrode collector 21, and an active material layer 22 and an insulating layer 23 provided on the positive electrode collector 21. The positive electrode collector 21 has a first surface 21a and a second surface 21b provided to be located on opposite sides. The active material layer 22 and the insulating layer 23 are provided on the first surface 21a. The first surface 21a includes an uncoated area 24 that is not covered by the active material layer 22 and the insulating layer 23. The uncoated area 24 is a part of the positive electrode collector 21 and is used as a positive electrode tab. The active material layer 22, the insulating layer 23, and the uncoated area 24 on the first surface 21a are arranged in order along the axial direction X of the prismatic battery 100, and the insulating layer 23 connects the active material layer 22 and the uncoated area 24.

[0026] The active material layer 22, the insulating layer 23, and the uncoated region 24 are further provided on the second surface 21b. The active material layer 22, the insulating layer 23, and the uncoated region 24 on the second surface 21b are arranged in order along the axial direction X of the columnar battery 100, and the insulating layer 23 connects the active material layer 22 and the uncoated region 24. The positions of the active material layer 22, the insulating layer 23, and the uncoated region 24 on the first surface 21a can correspond to the positions of the active material layer 22, the insulating layer 23, and the uncoated region 24 on the second surface 21b, respectively, but are not limited in the present invention. In another embodiment, the active material layer 22, the insulating layer 23, and the uncoated region 24 may be provided only on the first surface 21a or only on the second surface 21b.

[0027] The insulating layer 23 on the first surface 21a or the second surface 21b is adjacent to the active material layer 22, i.e., an edge of the insulating layer 23 is connected to an edge of the active material layer 22 along the axial direction X of the prismatic battery 100. Referring to Fig. 5, in another embodiment, the insulating layer 23 on the first surface 21a or the second surface 21b can partially cover and connect to the active material layer 22, i.e., the insulating layer 23 partially overlaps with the active material layer 22 along the thickness direction Y of the electrode assembly 10. The axial direction X of the prismatic battery 100 is perpendicular to the thickness direction Y.

[0028] The material of the positive electrode current collector 21 includes at least one of Ni, Ti, Cu, Ag, Au, Pt, Fe, Al, and compositions thereof. The active material layer 22 may include at least one of lithium cobalt oxide, lithium manganate, lithium nickel oxide, lithium nickel cobalt manganate, lithium iron phosphate, lithium manganese iron phosphate, lithium vanadium phosphate, lithium oxovanadyl phosphate, lithium-rich manganese material, lithium nickel cobalt aluminum oxide, and compositions thereof.

[0029] 1 and 2, the electrode assembly 10 further includes a flattened portion 101. The flattened portion 101 is manufactured by performing a flattening process on the non-coated region 24, that is, the flattened portion 101 is configured by the non-coated region 24 bent toward the winding central axis OO' of the electrode assembly 10. The flattened portion 101 has a flattened surface 102 formed by folding the non-coated region 24 toward the winding central axis of the electrode assembly 10 and overlapping them. The flattened surface 102 is formed by an end of the flattened portion 101 in the axial direction X of the prismatic battery 100, and the flattened surface 102 is a substantially flat surface for connection to a current collector (not shown). Note that the "flat surface" in the present invention includes not only a completely flat surface, but also a surface having irregularities or surface roughness to the extent that the non-coated region 24 and the current collector can be connected.

[0030] In the present invention, the hardness of the positive electrode current collector at the portion where the insulating layer is located is improved by providing the insulating layer 23. The insulating layer 23 plays a role in supporting the corresponding portion of the positive electrode current collector 21, and prevents a short circuit caused by the flattened portion 101 folding back and contacting the negative electrode piece 30 beyond the separator 40.

[0031] In some embodiments, the insulating layer 23 includes inorganic particles and a binder, and the inorganic particles include at least one of aluminum oxide, zinc oxide, calcium oxide, silicon oxide, zirconium oxide, magnesium oxide, titanium oxide, hafnium dioxide, tin oxide, cerium dioxide, nickel oxide, yttrium oxide, silicon carbide, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, barium sulfate, and boehmite. The binder is at least one selected from polyvinylidene fluoride, copolymer of vinylidene fluoride-hexafluoropropylene, polyamide, polyacrylonitrile, polyacrylic acid ester, polyacrylic acid, polyacrylate, polyvinylpyrrolidone, polyethylene alkoxy, polymethyl methacrylate, polytetrafluoroethylene, and polyhexafluoropropylene. By including the inorganic particles, the hardness of the insulating layer 23 is improved, and further, the supporting effect for the planarizing portion 101 is strengthened.

[0032] Referring to FIG. 3, the height of the flattened portion 101 along the axial direction X of the prismatic battery 100 is L. In some embodiments, L is 0.2 to 4 mm. If L is less than 0.2 mm, the insulating layer may be damaged by being significantly compressed by the lamination region of the flattened portion 101, and therefore cannot adequately support and protect the positive electrode current collector 21. If L exceeds 4 mm, the flattening amount of the non-coated region 24 is too small, and the flattened non-coated region 24 (flattened portion 101) is likely to bounce back, and the larger L is, the greater the loss of energy density of the prismatic battery 100 is. Taking the prismatic battery 100 with a height of 70 mm as an example, when L=4 mm, the energy density is reduced by 5.4% compared to when L=0.2 mm.

[0033] 3 and 4, the height of the insulating layer 23 on the first surface 21a or the second surface 21b along the axial direction X of the prismatic battery 100 is W. In some embodiments, W is 1 to 5 mm. If W is less than 1 mm, the insulating layer 23 is too narrow (too small in height), and there is a risk of insufficient application of the insulating layer 23 due to instability in the process capacity of the application process, so that the insulating layer cannot play a good role in supporting and protecting the positive electrode current collector 21 during flattening, and the larger W is, the greater the loss of energy density of the prismatic battery 100 will be. Taking the prismatic battery 100 with a height of 70 mm as an example, when W=5 mm, the energy density is reduced by 5.7% compared to when W=1 mm.

[0034] In some embodiments, W is 1.5 to 5 mm. In this manner, the process capability of coating the insulating layer 23 can be ensured with stability, and the insulating layer 23 can further have a sufficient supporting strength for supporting the positive electrode current collector 21.

[0035] 4, along the thickness direction Y of the electrode assembly 10, the thickness of the insulating layer 23 on the first surface 21a or the second surface 21b is denoted by h, and the thickness of the active material layer on the first surface 21a or the second surface 21b is denoted by H. In some embodiments, h and H satisfy 0.1H≦h≦H. If h<0.1H, the insulating layer 23 is too thin, which may cause coating leakage of the insulating layer 23 due to instability of the process capacity of the coating process, and the insulating layer cannot perform its role of supporting and protecting the positive electrode current collector 21 well during planarization.

[0036] In some embodiments, h and H satisfy 0.2H≦h≦0.9H. In this way, the process capability of coating the insulating layer 23 can be ensured and sufficient support strength of the insulating layer 23 for the positive electrode current collector 21 can be further ensured. If h>0.9H, the insulating layer 23 is too thick, and the insulating layer 23 has a certain hardness and brittleness. If the insulating layer 23 is too thick, it may burst under the action of flattening stress, and cannot play a role of supporting and protecting the positive electrode current collector 21 well. In some embodiments, H is 50 to 100 μm.

[0037] 3 and 4, along the winding direction Z of the electrode assembly 10, the positive electrode current collector 21 includes a first end 211 and a second end 212 opposite to the first end 211. The insulating layer 23 on the first surface 21a or the second surface 21b is disposed from the first end 211 to the second end 212. In other words, in the winding direction Z of the electrode assembly 10, the insulating layer 23 spreads evenly over the first surface 21a or the second surface 21b of the positive electrode current collector 21.

[0038] 2 and 3, the negative electrode piece 30 includes a negative electrode collector 31 and a negative electrode active material layer 32 provided on the negative electrode collector 31. The negative electrode active material layer 32 may be provided on two surfaces located on opposite sides of the negative electrode collector 31, or on only one surface, but this is not limited in the present invention. The negative electrode collector 31 includes an uncoated area 31a that is not covered by the negative electrode active material layer 32. The uncoated area 31a is used as a negative electrode tab and is connected to a case. In some embodiments, an insulating layer 23 may be further provided on the uncoated area 31a to cover a part of the uncoated area 31a so as to support the negative electrode collector 31a. The form in which the insulating layer 23 is provided on the negative electrode piece 30 may be the same as the form in which the insulating layer 23 is provided on the positive electrode piece 20, and a description thereof will be omitted here.

[0039] The material of the negative electrode current collector 31 may include at least one of Ni, Ti, Cu, Ag, Au, Pt, Fe, Al, and compositions thereof. The material of the negative electrode active material layer 32 may be at least one selected from graphite materials, alloy materials, lithium metal, and alloys thereof. The graphite material may be at least one selected from artificial graphite and natural graphite, and the alloy material may be at least one selected from silicon, silicon oxide, tin, and titanium sulfide.

[0040] The separator 40 is used to prevent direct contact between the positive electrode piece 20 and the negative electrode piece 30, thereby reducing the risk of a short circuit due to contact between the positive electrode piece 20 and the negative electrode piece 30. The separator 40 contains at least one insulating material selected from polyacrylic, polyethylene, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, polymethyl methacrylate, and polyethylene glycol.

[0041] The embodiment of the present invention further provides an electric device including the prismatic battery 100. The electric device specifically refers to a mobile phone, a portable device, a notebook computer, a battery car, an electric car, a steamship, a spaceship, an electric toy, an electric tool, etc. It is understood that the electric device is not limited to these, and may be any electric device using the prismatic battery 100.

[0042] Hereinafter, the characteristics of the battery provided by the present invention will be described with reference to specific examples and comparative examples.

[0043] Example 1 2 was placed in a case and an electrolyte was injected to obtain a finished battery. Here, the height L of the flattened portion 101 was 0.2 mm, the height W of the insulating layer 23 was 2 mm, the thickness h of the insulating layer 23 was 40 μm, and the thickness H of the active material layer 22 was 50 μm.

[0044] A Hi-pot test (insulation internal resistance test) was conducted on the completed battery manufactured in Example 1. Specifically, a voltage of 250 V was applied between the positive and negative electrode tabs of the electrode assembly 10 for 2 seconds, and the resistance was measured. If the resistance was ≧20 MΩ (megohms), the Hi-pot test was deemed to have been passed. If the resistance was <20 MΩ (megohms), the Hi-pot test was deemed to have not been passed, and the battery was deemed to be a Hi-pot defective product.

[0045] Comparison 1 A finished battery was manufactured in a manner similar to that of Example 1. The difference from Example 1 is that no insulating layer 23 is provided on the positive electrode current collector 21, and the uncoated area 24 is directly connected to the active material layer 22.

[0046] Examples 2 to 8 differ from Example 1 in that the height L of the flattened portion 101 is different.

[0047] Specific parameters and Hi-pot test results in Examples 1 to 8 and Comparative Example 1 are shown in Table 1.

[0048] [Table 1] Note: X / 20 means that out of 20 samples, X number of batteries passed the Hi-pot test.

[0049] In Example 1 and Comparative Example 1, the uncoated region 24 was flattened by a similar flattening process to form the flattened portion 101. Since the insulating layer 23 is not provided on the positive electrode current collector 21 in Comparative Example 1, the uncoated region 24 in Comparative Example 1 is easily folded back when flattened and comes into contact with the negative electrode active layer, causing a short circuit and failing to pass the Hi-pot test. As can be seen from Example 1 and Comparative Example 1, the provision of the insulating layer 23 significantly improved the pass rate of the Hi-pot test and reduced the risk of a short circuit.

[0050] As can be seen from Examples 1 to 8, when the height L of the flattened portion 101 is 0.2 to 4 mm, the pass rate of the Hi-pot test is 100%. When the height L of the flattened portion 101 is less than 0.2 mm, the insulating layer may be significantly compressed by the laminated region of the flattened portion 101 and may be damaged, resulting in a decrease in the pass rate of the Hi-pot test. When the height L of the flattened portion 101 exceeds 4 mm, the pass rate of the Hi-pot test is 100%, but the loss of energy density is large.

[0051] Examples 9 to 14 differ from Example 2 in that the height W of the insulating layer 23 is different. Specific parameters and the results of the Hi-pot test are shown in Table 2.

[0052] [Table 2]

[0053] As can be seen from Table 2, when the height W of the insulating layer 23 is 1 to 5 mm, the pass rate of the Hi-pot test is higher, and when the height W of the insulating layer 23 is 1.5 to 5 mm, the pass rate of the Hi-pot test is 100%. When W is less than 1 mm, there is a risk of insufficient application of the insulating layer 23 due to instability in the process capacity of the application process, so the pass rate of the Hi-pot test decreases. When W is more than 5 mm, the pass rate of the Hi-pot test is 100%, but W is too large and the occupied space is large, resulting in a large loss of volumetric energy density of the battery.

[0054] Examples 15 to 21 differ from Example 2 in that the ratio of thickness h of insulating layer 23 to thickness H of active material layer 22 is different. Specific parameters and Hi-pot test results are shown in Table 3.

[0055] [Table 3]

[0056] As can be seen from Table 3, when h and H satisfy 0.1H≦h≦H, the pass rate of the Hi-pot test is higher and within the acceptable range, and when h and H satisfy 0.2H≦h≦0.9H, the pass rate of the Hi-pot test is 100%. When h<0.1H, the insulating layer 23 is too thin, which may cause coating leakage due to instability of the process capacity of the coating process, and the pass rate of the Hi-pot test is reduced. When h>0.9H, the insulating layer 23 is too thick, which may cause rupture due to the action of flattening stress, and the pass rate of the Hi-pot test is reduced.

[0057] The above is merely a preferred embodiment of the present invention, and of course is not intended to limit the present invention, so that equivalent variations based on the present invention are included in the scope of the present invention.

Claims

1. A prismatic battery including an electrode assembly, the electrode assembly including a positive electrode piece, a separator, and a negative electrode piece stacked and wound, the positive electrode piece includes a positive electrode current collector, and an active material layer, an insulating layer, and an uncoated region are provided on a first surface of the positive electrode current collector, the active material layer, the insulating layer, and the uncoated region being aligned in order along an axial direction of the prismatic battery; The electrode assembly further includes a planarized portion, the planarized portion having a planarized surface formed by folding and overlapping the uncoated area toward a winding central axis of the electrode assembly.

2. 2. The prismatic battery according to claim 1, wherein the height L of the flattened portion is 0.2 to 4 mm along the axial direction of the prismatic battery.

3. 2. The prismatic battery according to claim 1, wherein a height W of the insulating layer is 1 to 5 mm along an axial direction of the prismatic battery.

4. The prismatic battery according to claim 3, wherein the height W of the insulating layer is 1.5 to 5 mm.

5. The prismatic battery according to claim 4, wherein the height W of the insulating layer is 1.5 to 3 mm.

6. 2. The prismatic battery according to claim 1, wherein h and H satisfy 0.1H≦h≦H, where h is a thickness of the insulating layer and H is a thickness of the active material layer.

7. The prismatic battery according to claim 6 , wherein h and H satisfy 0.2H≦h≦0.9H.

8. 8. The prismatic battery according to claim 6, wherein H is 50 to 100 μm.

9. 8. The prismatic battery according to claim 6, wherein h is 10 to 45 μm.

10. The prismatic battery according to claim 1, characterized in that the positive electrode current collector further has a second surface located opposite to the first surface, and the active material layer, the insulating layer and the uncoated area are also provided on the second surface.

11. 2. The prismatic battery according to claim 1, wherein the insulating layer contains inorganic particles, and the inorganic particles contain at least one of aluminum oxide, zinc oxide, calcium oxide, silicon oxide, zirconium oxide, magnesium oxide, titanium oxide, hafnium dioxide, tin oxide, cerium dioxide, nickel oxide, yttrium oxide, silicon carbide, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, barium sulfate, and boehmite.

12. An electrical device comprising the prismatic battery according to any one of claims 1 to 11.

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