Conductive film and film capacitor containing the same

Abstract

The present invention relates to a conductive film, which has a conductive film portion and a blank margin portion on one side surface of a base film, the conductive film portion has a conductive layer, the conductive layer includes a thickened area, a transition area and an active area, the thickened area, the transition area, the active area and the blank margin portion are arranged in sequence in the transverse direction of the base film; a first isolation zone extending longitudinally and a second isolation zone extending non-longitudinally are provided in the active area, the first isolation zone is curved and fuses are distributed on the first isolation zone. When a thin film capacitor formed by winding the above conductive film is used, the current will flow from the maximum value of the thickened area to the zero value of the blank margin portion, and heat will be generated when the current encounters the first isolation zone and the second isolation zone. The first isolation zone of the above conductive film extends longitudinally and is curved, so that the position where the current generates heat can be dispersed, thereby avoiding the concentration of heat and achieving the purpose of reducing heat.

Description

Technical Field

[0001] The present invention relates to the technical field of capacitors, and in particular to a conductive film and a thin film capacitor containing the conductive film. Background Art

[0002] With the rapid development of the electronics industry, capacitors, as an important energy storage electronic component, are increasingly widely used. Film capacitors such as metallized film capacitors (i.e. capacitors containing metallized film) have gradually replaced traditional capacitors due to their excellent mechanical and electrical properties, such as good flexibility, low dielectric loss, high voltage resistance, and small changes in dielectric constant with temperature and frequency. As the use of metallized film capacitors becomes more and more common, higher requirements are also placed on their safety performance. As the main material of capacitors, metallized safety film often plays a decisive role in improving the safety of film capacitors.

[0003] Traditional metallized safety film designs generally use a linear isolation zone, and the fuse positions are arranged in a straight line in the vertical direction (such as the metallized safety films in patents No. CN1703764A, No. CN102308350A, No. 207183076U and No. 205828152U). After being made into a capacitor, during the use of a smoothing loop in a DC filter or inverter circuit, the equivalent series resistance (ESR) is large and the heat is too concentrated, which can easily lead to a decrease in the withstand voltage of the film, thereby shortening the life of the capacitor. Summary of the invention

[0004] Based on this, it is necessary to provide a conductive film and a thin film capacitor containing the conductive film that have a small equivalent series resistance, dispersed heat, and are beneficial for reducing the drop in the withstand voltage of the film.

[0005] A conductive film comprises a base film, wherein a conductive film portion and a blank margin portion are provided on one side surface of the base film, wherein the conductive film portion comprises a conductive layer, wherein the conductive layer comprises a thickened area, a transition area and an active area, wherein the thickened area, the transition area, the active area and the blank margin portion are sequentially arranged in the lateral direction of the base film; wherein a first isolation zone extending longitudinally and a second isolation zone extending non-longitudinally are provided in the active area, wherein the first isolation zone is curved and fuses are distributed on the first isolation zone.

[0006] In one embodiment, the first isolation zone is in the shape of a periodically distributed curve.

[0007] In one embodiment, the first isolation zone is in the shape of a sine-cosine curve.

[0008] In one embodiment, the projected length of one period of the first isolation zone in the longitudinal direction is 3.0 mm to 25.0 mm.

[0009] In one of the embodiments, the amplitude of the first isolation zone is 1.0 mm to 12.5 mm.

[0010] In one embodiment, the width of the first isolation zone is 0.1 mm to 0.4 mm.

[0011] In one embodiment, at least two of the plurality of fuses distributed on the first isolation zone are staggered in the longitudinal direction.

[0012] In one embodiment, the angle between the extension direction of the second isolation zone and the longitudinal direction is 30° to 90°.

[0013] In one embodiment, the second isolation zone is in a straight line or a curved line.

[0014] In one embodiment, the width of the second isolation zone is 0.1 mm to 0.4 mm.

[0015] In one embodiment, the number of the second isolation zones is two or more, and the two or more second isolation zones are arranged in parallel.

[0016] In one embodiment, the distance between adjacent second isolation zones is 3.0 mm to 25.0 mm.

[0017] In one embodiment, there are multiple first isolation strips.

[0018] In one embodiment, a fuse is disposed on the second isolation zone, and at least two of the first isolation zones are spaced between the fuse on the second isolation zone and the transition zone.

[0019] In one embodiment, the number of the second isolation zones is two or more, and the two or more second isolation zones are arranged in parallel.

[0020] In one embodiment, the fuses on any adjacent second isolation zones are staggered in the longitudinal direction, or only one of any two adjacent second isolation zones is provided with the fuse.

[0021] In one embodiment, the length of the fuse is 0.1 mm to 0.4 mm.

[0022] A film capacitor, wherein the capacitor core is formed by winding the conductive film described in any one of the above embodiments.

[0023] When the film capacitor formed by winding the conductive film is used, the current will flow from the maximum value of the thickened area to the zero value of the blank margin, and when the current encounters the first isolation zone and the second isolation zone, heat will be generated. The first isolation zone of the conductive film extends longitudinally, and the first isolation zone is curved, so that the location where the current generates heat can be dispersed, thereby avoiding the concentration of heat and achieving the purpose of reducing heat.

[0024] In addition, a fuse is provided on the first isolation zone. When an abnormality occurs during the use of the capacitor, the fuse will be activated to provide protection. The conductive film disperses the positions of the fuses, for example, at least two fuses are staggered in the longitudinal direction, so that the heat generated when the fuses are activated will not be concentrated in the same position, reducing damage to the base film, thereby reducing the drop in the capacitor's withstand voltage and extending the capacitor's service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic top view of the conductive film of the present invention. DETAILED DESCRIPTION

[0026] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0027] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0029] The metals described herein include single-component metals, metal alloys formed by multiple single-component metals, and conductive materials obtained by adding non-metallic components to single-component metals or metal alloys.

[0030] like Figure 1As shown, a conductive film 10 includes a base film 100, and a conductive film portion 101 and a blank margin portion 102 are provided on one side surface of the base film 100. The conductive film portion 101 is provided with a conductive layer 200. The conductive layer 200 can be, but is not limited to, a metal vapor deposition layer. When the conductive layer is a metal vapor deposition layer, the conductive film 10 is a metallized safety film. The conductive layer 200 includes a thickened area 201, a transition area 202, and an active area 203. The thickened area 201 is used for gold spraying when making capacitors, and can improve the current resistance characteristics of the capacitors; the active area 203 is the area where the capacitors withstand withstand voltage; the transition area 202 is the transition from the thickened area 201 to the active area 203, and is used to connect the thickened area 201 and the active area 203. The thickened area 201, the transition area 202, the active area 203, and the blank margin portion 102 are sequentially arranged in the lateral direction of the base film 100. A longitudinally extending first isolation zone 210 and a non-longitudinally extending second isolation zone 220 are provided in the active area 203. The first isolation zone 210 is curved and a first fuse 310 is distributed on the first isolation zone 210. The first fuse 310 is used to connect the areas on both sides of the first isolation zone 210.

[0031] In a specific example, the first isolation zone 210 is in the shape of a periodically distributed curve, which may be a regular curve or a randomly distributed irregular curve, preferably a regular curve, a curve composed of straight line segments or a curve composed of non-straight line segments, more preferably a sine-cosine curve (sine or cosine curve).

[0032] In a more specific example, the projected length of one period of the first isolation zone 210 in the longitudinal direction is between 3.0 mm and 25.0 mm, such as 3.0 mm, 5.0 mm, 8.0 mm, 10.0 mm, 12.0 mm, 15.0 mm, 18.0 mm, 20.0 mm, 22.0 mm, 24.0 mm or 25.0 mm, etc. Further, the amplitude of the first isolation zone 210 is between 1.0 mm and 12.5 mm, such as 1.0 mm, 2.0 mm, 3.0 mm, 4.0 mm, 5.0 mm, 6.0 mm, 7.0 mm, 8.0 mm, 9.0 mm, 10.0 mm, 11.0 mm, 12.0 mm or 12.5 mm, etc. Furthermore, the width of the first isolation zone 210 is between 0.1 mm and 0.4 mm, such as 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm or 0.4 mm.

[0033] In a specific example, a plurality of first fuses 310 are distributed on the first isolation zone 210. At least two of the plurality of first fuses 310 are staggered in the longitudinal direction, and preferably, adjacent first fuses 310 are staggered in the longitudinal direction, so that excessive concentration of heat generated when the first fuses 310 are actuated can be avoided, so as to effectively disperse the heat generation source.

[0034] The second isolation zone 220 is not extended in the longitudinal direction. In a specific example, the angle between the extension direction of the second isolation zone 220 and the longitudinal direction is 30° to 90°, such as 30°, 45°, 60°, 75°, 80°, 85° or 90°. Preferably, the angle between the extension direction of the second isolation zone 220 and the longitudinal direction is 90°, that is, the extension direction of the second isolation zone 220 is perpendicular to the longitudinal direction, and the second isolation zone 220 extends in the transverse direction.

[0035] One end of the second isolation zone 220 is located at the junction of the transition zone 202 and the active zone 203, and the other end extends to the junction of the active zone 203 and the blank margin portion 102. In a specific example, the second isolation zone 220 can be straight or curved, such as a curve similar to the first isolation zone 210. In the specific example shown in the figure, the second isolation zone 220 is straight, one end of which is located at the junction of the first isolation zone 210 and the transition zone 202, and the other end extends to the junction of the active zone 203 and the blank margin portion 102.

[0036] The width of the second isolation zone 220 is between 0.1 mm and 0.4 mm, such as 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm or 0.4 mm.

[0037] Further, in a specific example, the number of the second isolation belts 220 is two or more and the plurality of second isolation belts 220 are arranged in parallel. Furthermore, the distance between adjacent second isolation belts 220 is between 3.0 mm and 25.0 mm, such as 3.0 mm, 5.0 mm, 8.0 mm, 10.0 mm, 12.0 mm, 15.0 mm, 18.0 mm, 20.0 mm, 22.0 mm, 24.0 mm or 25.0 mm.

[0038] Furthermore, in a specific example, there are also multiple first isolation zones 210, as shown in the specific example. Preferably, multiple first isolation zones 210 are also arranged in parallel. More preferably, a second fuse 320 is provided on the second isolation zone 220. The second fuse 320 is used to connect the areas on both sides of the second isolation zone 220. There are at least two first isolation zones 210 between the second fuse 320 on the second isolation zone 220 and the transition zone 202, that is, the second fuse 320 is not provided on the second isolation zone 220 between the two first isolation zones 210 closest to the transition zone 202. By setting it in this way, it can be prevented that when some grids in the multiple first isolation zones 210 extending longitudinally fail, the grids on the right side thereof are also failed, and the stability and reliability of the product can be improved.

[0039] Preferably, the number of the second isolation belts 220 is two or more and the plurality of second isolation belts 220 are arranged in parallel. The second fuses 320 on any adjacent second isolation belts 220 are staggered in the longitudinal direction, or only one of any two adjacent second isolation belts 220 is provided with a second fuse 320.

[0040] The first fuse 310 and / or the second fuse 320 both extend along the width direction of the corresponding isolation zone. Preferably, the length of the first fuse 310 and the second fuse 320 is between 0.1 mm and 0.4 mm, such as 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm or 0.4 mm.

[0041] The present invention further provides a thin film capacitor, wherein the capacitor core is formed by winding the conductive film 10 of any of the above specific examples.

[0042] When the thin film capacitor formed by winding the conductive film 10 is in use, the current will flow from the maximum value of the thickened area 201 to the zero value of the blank margin 102, and heat will be generated when the current encounters the first isolation zone 210 and the second isolation zone 220. The first isolation zone 210 of the conductive film 10 extends longitudinally and is curved, so that the location where the current generates heat can be dispersed, thereby avoiding the concentration of heat and achieving the purpose of reducing heat.

[0043] In addition, a first fuse 310 is disposed on the first isolation zone 210 . When an abnormality occurs during the use of the capacitor, the first fuse 310 will be activated to provide protection.

[0044] The conductive film 10 disperses the positions of the first fuse 310 and / or the second fuse 320. For example, at least two fuses are staggered in the longitudinal direction. This prevents the heat generated when the fuses are actuated from being concentrated in the same position, thereby reducing damage to the base film 100, thereby reducing the drop in the withstand voltage of the capacitor and extending the service life of the capacitor.

[0045] The conductive film of the present invention and the thin film capacitor containing the conductive film are further described in detail below in conjunction with specific embodiments.

[0046] The following embodiments and comparative examples are described by taking the metallized safety film as an example. The tests involved in the following embodiments and comparative examples include capacity (μF) measurement, ESR (10KHz) measurement, temperature rise measurement and life test. The following embodiments and comparative examples are mainly used to illustrate that the technical concept of the present invention can reduce the hot spot temperature of the capacitor, thereby extending the service life of the capacitor. The values ​​of the specific materials and dimensions involved should not be limited. The materials and dimensions of the corresponding parts of the conductive film described herein shall be based on the data range and specific examples of the materials and dimensions given above.

[0047] The metallized safety film of Example 1 has a lateral width of 26.0 mm, a blank margin width of 1.5 mm, a thickened area resistance of 3.0 ohm (metal is zinc-aluminum alloy), an active area resistance of 20 ohm (metal is pure aluminum), and a base film thickness of 2.5 μm. In Example 1, a first isolation zone extending longitudinally is set as one, which is a sine-cosine waveform curve, and a plurality of fuses are distributed thereon; a second isolation zone is set transversely, and there are a plurality of second isolation zones, and the plurality of second isolation zones are set in parallel.

[0048] The structure of the metallized safety film of Comparative Example 1 is substantially the same as that of Example 1, except that the second isolation zone extending longitudinally is in a straight line shape.

[0049] Other relevant structural dimensions of the metallized safety film of Example 1 and Comparative Example 1 are shown in Table 1 below.

[0050] Table 1

[0051]

[0052] The metallized safety films of Example 1 and Comparative Example 1 were used to wind capacitor cores with a capacity of 42 μF and fabricate capacitors.

[0053] 1) The two groups of capacitors were tested for general characteristics. The test results are shown in Table 2.

[0054] Table 2

[0055]

[0056] 2) Perform temperature rise test on two groups of capacitors

[0057] Test conditions: ambient temperature 85°C, current 15A, current frequency: 10KHz, test points A, B, and C are located on one side, the middle, and the other side of the two first isolation zones of the two metallized safety films forming the capacitor core.

[0058] The test results are shown in Table 3.

[0059] Table 3

[0060]

[0061] 3) Perform life test on two groups of capacitors

[0062] Test conditions: ambient temperature 85°C, voltage 500VDC, current 150A, time 1000 hours. Test results are shown in Table 4.

[0063] Table 4

[0064]

[0065] The metallized safety film of Example 2 has a lateral width of 50.0 mm, a blank margin width of 1.5 mm, a thickened area resistance of 3.0 ohm (metal is zinc-aluminum alloy), an active area resistance of 20 ohm (metal is pure aluminum), and a base film thickness of 2.5 μm. In Example 2, two first isolation belts extending longitudinally are provided, which are in the shape of a sine-cosine waveform, and are arranged in parallel, and each of them is provided with a plurality of fuses; the second isolation belt is arranged in the horizontal direction, and there are a plurality of second isolation belts, and a plurality of second isolation belts are arranged in parallel. Fuses are also distributed on the second isolation belt, and the fuse on the second isolation belt is separated from the transition zone by two first isolation belts, and only one of any adjacent second isolation belts is provided with a fuse.

[0066] The structure of the metallized safety film of Comparative Example 2 is substantially the same as that of Example 2, except that the two second isolation zones extending longitudinally are in a straight line shape.

[0067] Other relevant structural dimensions of the metallized safety films of Example 2 and Comparative Example 2 are shown in Table 5 below.

[0068] Table 5

[0069]

[0070] The metallized safety films of Example 2 and Comparative Example 2 were used to wind capacitor cores with a capacity of 75 μF and fabricate capacitors.

[0071] 1) Perform general characteristic tests on the two groups of capacitors. The test results are shown in Table 6.

[0072] Table 6

[0073]

[0074] 2) Perform temperature rise test on two groups of capacitors

[0075] Test conditions: ambient temperature 85°C, current 15A, current frequency: 10KHz; test points A, C, and B are respectively located on the two first isolation zones close to the corresponding transition zones of the two metallized safety films forming the capacitor core, and in the middle of the two first isolation zones away from the transition zones.

[0076] The test results are shown in Table 7.

[0077] Table 7

[0078]

[0079] 3) Perform life test on two groups of capacitors

[0080] Test conditions: ambient temperature 85°C, voltage 500VDC, current 150A, time 1000 hours. Test results are shown in Table 8.

[0081] Table 8

[0082]

[0083] The metallized safety film of Example 3 has a lateral width of 50.0 mm, a blank margin width of 1.5 mm, a thickened area resistance of 3.0 ohm (metal is zinc-aluminum alloy), an active area resistance of 20 ohm (metal is pure aluminum), and a base film thickness of 2.5 μm. In Example 3, three first isolation belts extending longitudinally are arranged in a sine-cosine waveform curve, three parallel arrangements, and multiple fuses are distributed on each belt; the second isolation belt is arranged in a transverse direction, and multiple second isolation belts are arranged in parallel. Fuses are also distributed on the second isolation belt, and the fuses on the second isolation belt are located on both sides of the middle first isolation belt, and the fuses on the adjacent second isolation belts are staggered on both sides of the middle first isolation belt (that is, on one side of the middle first isolation belt, only one of the adjacent second isolation belts is provided with a fuse, and the same is true on the other side of the middle first isolation belt).

[0084] The structure of the metallized safety film of Comparative Example 3 is substantially the same as that of Example 3, except that the two second isolation zones extending longitudinally are in a straight line shape.

[0085] Other relevant structural dimensions of the metallized safety film of Example 3 and Comparative Example 3 are shown in Table 9 below.

[0086] Table 9

[0087]

[0088] The metallized safety films of Example 3 and Comparative Example 3 were used to wind capacitor cores with a capacity of 75 μF and fabricate capacitors.

[0089] 1) Perform general characteristic tests on the two groups of capacitors. The test results are shown in Table 10.

[0090] Table 10

[0091]

[0092] 2) Perform temperature rise test on two groups of capacitors

[0093] Test conditions: ambient temperature 85°C, current 15A, current frequency: 10KHz; test points A, C, and B are respectively located between the first and second first isolation zones close to the corresponding transition zones of the two metallized safety films forming the capacitor core, and in the middle of the two first isolation zones away from the transition zones.

[0094] The test results are shown in Table 11.

[0095] Table 11

[0096]

[0097] 3) Perform life test on two groups of capacitors

[0098] Test conditions: ambient temperature 85°C, voltage 550VDC, current 150A, time 1000 hours. Test results are shown in Table 12.

[0099] Table 12

[0100]

[0101] It can be seen from the above embodiments and comparative examples that the capacitor made of the metallized safety film designed by the present invention can disperse the heat generated by the capacitor, reduce the temperature of the hottest point of the capacitor, and thus extend the life of the capacitor.

[0102] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0103] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A conductive film, characterized in that: The invention comprises a base film, wherein a conductive film portion and a blank margin portion are provided on one side surface of the base film, wherein the conductive film portion has a conductive layer, wherein the conductive layer comprises a thickened area, a transition area and an active area, wherein the thickened area, the transition area, the active area and the blank margin portion are sequentially arranged in the transverse direction of the base film; wherein a first isolation zone extending longitudinally and a second isolation zone extending non-longitudinally are provided in the active area, wherein the first isolation zone is in the shape of a sine-cosine curve and fuses are distributed on the first isolation zone; Any adjacent fuses distributed on the first isolation zone are staggered in the longitudinal direction.

2. The conductive film according to claim 1, wherein A projection length of one period of the first isolation zone in the longitudinal direction is 3.0 mm to 25.0 mm.

3. The conductive film according to claim 2, wherein: The amplitude of the first isolation zone is 1.0 mm to 12.5 mm.

4. The conductive film according to claim 1, wherein The width of the first isolation zone is 0.1 mm to 0.4 mm.

5. The conductive film according to any one of claims 1 to 4, wherein The angle between the extension direction of the second isolation zone and the longitudinal direction is 30° to 90°.

6. The conductive film according to any one of claims 1 to 4, wherein The second isolation zone is in a straight line or a curved line.

7. The conductive film according to any one of claims 1 to 4, wherein The width of the second isolation zone is 0.1 mm to 0.4 mm.

8. The conductive film according to any one of claims 1 to 4, wherein The number of the second isolation belts is two or more, and the two or more second isolation belts are arranged in parallel.

9. The conductive film according to claim 8, wherein The distance between adjacent second isolation zones is 3.0 mm to 25.0 mm.

10. The conductive film according to any one of claims 1 to 4, wherein The first isolation belts include a plurality of belts.

11. The conductive film according to claim 10, wherein: A fuse is arranged on the second isolation zone, and at least two of the first isolation zones are spaced between the fuse on the second isolation zone and the transition zone.

12. The conductive film according to claim 11, wherein The number of the second isolation belts is two or more, and the two or more second isolation belts are arranged in parallel.

13. The conductive film according to claim 12, wherein: The fuses on any adjacent second isolation zones are staggered in the longitudinal direction, or only one of any two adjacent second isolation zones is provided with the fuse.

14. The conductive film according to any one of claims 1 to 4 and 11 to 13, wherein The length of the fuse is 0.1 mm to 0.4 mm.

15. A film capacitor, characterized in that: The capacitor core is formed by winding the conductive film according to any one of claims 1 to 14.

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