ELECTRICAL DEVICE, IN PARTICULAR MICROBATTERY, AND METHOD FOR THE PRODUCTION

Abstract

An electrical device includes: a housing part made of a metal and including a feedthrough therethrough, an opening of the feedthrough, a first region, and a second region, the opening receiving a conductive material or a conductor in a glass material or a glass-ceramic material, wherein: (i) the conductive material has a first coefficient of expansion α.sub.1, the glass material or the glass-ceramic material has a second coefficient of expansion α.sub.2, and the housing part has a third coefficient of expansion α.sub.3, the third coefficient of expansion α.sub.3 being always greater than the second coefficient of expansion α.sub.2; or (ii) the first region including a width W that is substantially perpendicular to the axis of the at least one opening, the width W of the first region being always greater than a thickness D.sub.2 and a thickness D.sub.E of the second region; or (iii) a combination of (i) and (ii).

Claims

1. An electrical device, comprising: a housing part of a housing, the housing part being made of a metal and including a feedthrough therethrough, at least one opening as a part of the feedthrough, a first region, and a second region, the at least one opening extending about an axis, the first region including the at least one opening, the second region being adjacent to the at least one opening, the at least one opening receiving a conductive material or a conductor in a glass material or a glass-ceramic material, wherein: (i) the conductive material has a first coefficient of expansion α.sub.1, the glass material or the glass-ceramic material has a second coefficient of expansion α.sub.2, and the housing part has a third coefficient of expansion α.sub.3, the third coefficient of expansion α.sub.3 being always greater than the second coefficient of expansion α.sub.2; or (ii) the first region including a width W that is substantially perpendicular to the axis of the at least one opening, the width W of the first region being always greater than a thickness D.sub.2 and a thickness D.sub.E of the second region; or (iii) a combination of (i) and (ii).

2. The electrical device according to claim 1, wherein the housing part includes a flange or a flexible flange, the flange or the flexible flange having a free space F between a raised region or a lowered region of the housing part and having a connecting region, wherein the flange or the flexible flange is connected to the housing.

3. The electrical device according to claim 2, wherein the flange or the flexible flange is connected to the housing by way of welding or laser welding or soldering, in such a manner that a connection therebetween is substantially gas-tight and that a helium leakage rate of less than 10−8 mbar l/sec is provided.

4. The electrical device according to claim 2, wherein the flexible flange is produced by reshaping of a sheet material part, wherein the flexible flange has a thickness D.sub.2 of the sheet material part.

5. The electrical device according to claim 2, wherein the flexible flange consists of one of the following materials: a ferritic high grade steel with a coefficient of expansion in a range of 10 to 12.Math.10−K−1; a normal steel with a coefficient of expansion in a range of 12 to 13.Math.10−K−1; a Duplex high grade steel with a coefficient of expansion in a range of 13 to 14.Math.10−K−1; an austenitic high grade steel with a coefficient of expansion in a range of 16 to 18.Math.10−6 K−1.

6. The electrical device according to claim 1, wherein: (i) the thickness D.sub.2 and the thickness D.sub.E are in a range of 0.1 mm to 1 mm or 0.1 mm to 0.6 mm; or (ii) the width W is in a range of 0.6 mm to 1 mm or in a range of 0.7 mm to 0.9 mm; or (iii) a combination of (i) and (ii).

7. The electrical device according to claim 1, wherein at least one of: the third coefficient of expansion α.sub.3 is in a range of 12.Math.10−6 1/K to 19.Math.10−6 1/K; the second coefficient of expansion α.sub.2 is in a range of 9.Math.10−6 1/K to 11.Math.10−6 1/K; and the first coefficient of expansion α.sub.1 is in a range of 6.Math.10−6 1/K to 11.Math.10−6 1/K.

8. The electrical device according to claim 1, wherein at least one of a metal of the housing, the metal of the housing part, and/or a metal of the conductor is iron, an iron alloy, an iron-nickel alloy, an iron-nickel-cobalt alloy, KOVAR, steel, stainless steel, high grade steel, aluminum, an aluminum alloy, AISiC, magnesium, a magnesium alloy, copper, a copper alloy, titanium, or a titanium alloy.

9. The electrical device according to claim 1, wherein the housing part in the first region in a region of the at least one opening comprises a collar, thereby forming an inside wall having a height that is greater than a material thickness or the thickness D.sub.2.

10. The electrical device according to claim 9, wherein the collar is domed or reshaped with at least one of an indentation and a protrusion.

11. The electrical device according to claim 9, wherein a glassing length EL of the glass material or the glass-ceramic material is determined by a height of the collar.

12. The electrical device according to claim 9, wherein the material thickness or the thickness D.sub.2 of the second region is equal to a material thickness or a thickness of at least one of at least a component elected from the collar, an indentation of the collar, and a protrusion of the collar.

13. The electrical device according to claim 1, wherein the electrical device has a total height which is at most 40 mm, at most 20 mm, at most 5 mm, at most 4 mm, at most 3 mm, in a range of 1 mm to 40 mm, in a range of 1 mm to 5 mm, or in a range of 1 mm to 3 mm.

14. The electric device according to claim 1, wherein the housing part includes a flange or a flexible flange, wherein a material of the flange or the flexible flange is selected such that an expulsion force of the conductor is set by glass pre-stresses which act via the glass material upon the conductor.

15. The electrical device according to claim 14, wherein by adjustment of the expulsion force of the conductor a safety vent function of the conductor is set.

16. The electrical device according to claim 1, wherein an expulsion force of the conductor and a safety vent function of the conductor is set by at least one of the following measurements: a thickness of a glassing; using different ones of a plurality of glass materials; a different bubble content in a glass; a structured glass surface based on a shape of a glass part prior to sealing; a structured glass surface based on a shape of a glass part during sealing; a structured glass surface through a laser treatment after sealing; a plurality of notches or a plurality of tapers in the glass material, on one or both sides of the housing; a plurality of notches or a plurality of tapers in at least one of the conductor, the housing, the housing part, and a base body of the housing.

17. The electrical device according to claim 1, wherein the electrical device is an electrical storage device or a sensor housing.

18. The electrical device according to claim 1, wherein the electrical device is a microbattery or a condensator.

19. A method to produce an electrical device, the method comprising the steps of: providing that the electrical device includes a feedthrough and a housing part, the housing part including at least one opening, the at least one opening receiving a conductive material or a conductor in a glass material or a glass-ceramic material, the housing part being a sheet metal part having a material thickness or a thickness D.sub.1; introducing the at least one opening into the sheet metal part; pressing outside a region around the at least one opening down to a thickness D.sub.2; inserting the conductor in the glass material or the glass-ceramic material into the at least one opening; and heating the sheet metal part with a material inserted into the at least one opening, so that a compression seal of the conductor in the glass material or the glass-ceramic material is performed.

20. A method to produce an electrical device, the method comprising the steps of: providing that the electrical device includes a feedthrough and a housing part, the housing part including at least one opening, the at least one opening receiving a conductive material or a conductor in a glass material or a glass-ceramic material, the housing part being a sheet metal part having a material thickness or a thickness D.sub.2; introducing the at least one opening into the sheet metal part; drawing up a collar around the at least one opening by way of reshaping or providing a collar around the at least one opening with at least one of an indentation and a protrusion; inserting the conductor in the glass material or the glass-ceramic material into the at least one opening with the collar; and heating the sheet metal part with a material inserted into the at least one opening, so that a compression seal of the conductor in the glass material or the glass-ceramic material is performed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0296] The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:

[0297] FIG. 1a is a cross section through a housing, in particular a battery cover with an opening for sealing into it a conductor, wherein the sheet metal part is pressed down adjacent to the opening to a low material thickness, according to a first embodiment;

[0298] FIG. 1b a cross section through a housing part according to FIG. 1a with a conductor sealed into the opening;

[0299] FIG. 2a a cross section through a housing part, in particular a battery cover with an opening for sealing into it a conductor, wherein the sheet metal part includes a collar that provides a wall for sealing a conductor into the opening with collar;

[0300] FIG. 2b a cross section through a housing part according to FIG. 2a with a conductor sealed into the opening;

[0301] FIG. 3 a cross section through a housing part, in particular a battery cover, with an opening for sealing in a conductor, wherein the housing cover includes a flexible flange;

[0302] FIG. 4 detail of the housing part with flexible flange according to FIG. 3;

[0303] FIG. 5 housing part with flexible flange, wherein the flexible flange is obtained by reshaping a sheet metal part having a thickness D.sub.2;

[0304] FIG. 6 housing part with a flexible flange according to FIG. 5, wherein the necessary seal length EL is specified, for example for ferritic high grade steel;

[0305] FIG. 7 housing part with a flexible flange according to FIG. 5, wherein the necessary sealing length EL is specified, for Duplex high grade steel or austenitic high grade steel;

[0306] FIG. 8 microbattery with an inventive housing part or battery cover according to FIGS. 3, 4, 5, 6, 7;

[0307] FIGS. 9a, 9b and 9c is each a feedthrough with conductor, including connecting head;

[0308] FIG. 10a conductor, sealed into an opening in a housing part, in particular base body without meniscus of the glass or glass ceramic material to the housing part, in particular the base body; and

[0309] FIG. 10b conductor, sealed into an opening in a housing part, in particular base body with a meniscus of the glass or glass ceramic material to the housing part, in particular the base body.

[0310] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrate embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.

DETAILED DESCRIPTION OF THE INVENTION

[0311] In FIG. 1 an inventive housing part or sheet metal part 1 is shown as a part of a housing, in particular a housing of a storage device, for example a battery, in particular a microbattery, as illustrated in FIG. 8. The sheet metal part includes an opening 3 into which a conductor can be sealed. The sealed in conductor is not shown in FIG. 1a. The sheet metal part with inserted conductor is shown in FIG. 1b. The thin section 5 of the sheet metal part with an opening 3 as part of the housing of a storage device is produced by pressing down the sheet metal part. This means that initially a sheet metal with sufficient wall thickness of approximately 0.6 mm is provided for sealing of a conductor into a glass or glass ceramic material. Then, an opening is introduced by way of a stamping process into the sheet metal part with sufficient wall thickness. After introducing opening 3—for example by way of a stamping process—into sheet metal part 1, the sheet metal part with a thickness or material strength D.sub.1 is reduced in its thickness in regions 5, for example by way of pressing down. The thickness or the sheet metal part into which sealing occurs is, for example, 0.6 mm, and the thickness of the pressed-down part of the sheet metal part is, for example, only 0.2 mm.

[0312] In FIG. 1a the thickness of the sheet metal in the region of the opening into which the sealing is performed, is identified as D.sub.1. Thickness D1 corresponds with the length which is required for a compression seal of a conductor in a glass or glass ceramic material, as shown in FIG. 1b. Because of the material thickness or thickness D.sub.1, a prestress is applied to the glass or glass-ceramic material and the conductor encased in the glass or glass ceramic material due to the different coefficients of expansion of the sheet metal part or housing part and the glass or glass-ceramic material or the conductor, so that compression sealing of the conductor is provided. To provide the prestress, the region of thickness D.sub.1 includes substantially perpendicular to the axis A of opening 3 a width W. Width W ensures that the metal surrounding the opening or the metal ring surrounding the opening can provide the necessary prestress for the compression seal. The pressure seal is characterized in that the helium leakage rate is less than 1.Math.10.sup.−8 mbar/sec at 1 bar pressure differential. According to the present invention, the coefficient of expansion α.sub.1 of the conductor and the coefficient of expansion α.sub.2 of the glass material differ from the coefficient of expansion α.sub.3 of the sheet metal part or housing material. To apply the necessary prestress, the coefficient of expansion α.sub.3 of the sheet metal part or housing part is approximately 2 to 8.Math.10.sup.6 1/K greater than the coefficient of expansion of the conductor or glass ceramic material. For example, the coefficient of expansion α.sub.3 of the housing part, in particular the sheet metal part, is in the range 12 to 19.Math.10.sup.−6 1/K, and that of the conductive material or glass or glass ceramic is in the range 9 to 11.Math.10.sup.−6 1/K.

[0313] The housing part consists optionally of a Duplex high grade steel with a coefficient of expansion of approximately 15.Math.10.sup.−6 1/K or of an austenitic material with a coefficient of expansion of approximately 18.Math.10.sup.−6 1/K. With the illustrated embodiment of a housing or sheet metal part, a compression seal is provided even with a very thin sheet metal wall thickness and a seal length of only 0.6 mm. Despite the thin sheet thickness of only 0.6 mm, the ring with thickness D.sub.1 surrounding the opening provides sufficient prestress for the compression seal.

[0314] The connection to the remaining housing part of a battery housing is made in the region of the thin sheet metal part with thickness D.sub.2 by a protrusion 7 inserted into the thin sheet metal part, for example by way of a welded joint.

[0315] FIG. 1b shows a housing part according to FIG. 1a with a sealing glass ring 9 having a thickness D.sub.1 and conductor 20 sealed in sealing glass ring 9. The glass material which accommodates conductor 20 is marked with reference number 22. The thickness of pressed sheet metal part 5 outside the sealing glass ring is D.sub.2. The glass ring has a width W, which is used to apply the necessary compression pressure for the compression seal.

[0316] An additional embodiment may provide that thickness D.sub.2 corresponds with thickness D.sub.1.

[0317] Instead of the sealing ring as shown in FIGS. 1a and 1b, an alternative embodiment can provide that the sheet metal used generally has a thickness D.sub.2, and an edge 30 required for sealing in the region of opening 3 is not provided by a solid sheet metal part, but by drawing up or deep-drawing an edge 40 of thin sheet metal part 5, as shown in FIGS. 2a and 2b. Drawn up edge 40 is then present in the shape of a collar. As shown in FIG. 2b, conductor 20 is sealed in a glass material 22 into drawn-up collar 40. Collar 40 includes an indentation 42 and a bulge 44. The indentation provides a certain flexibility to avoid glass breakages. The bulge has a width W, essentially toward axis A, which ensures that sufficient prestress is applied by the housing part. In the described design example, width W is approximately 0.6 mm. The conductor sealed into the opening in the region of the collar is subjected to sufficient prestress for a compression seal.

[0318] The advantage of the method according to FIGS. 2a and 2b compared to the method according to FIGS. 1a and 1b is, that pressing down of the sheet metal is not necessary. The metal with consistent metal thickness D.sub.2 needs only to be reshaped, so that collar 40 is formed having a height consistent with seal length EL and having indentations 42 and bulges 44. Seal length EL is at least mm and thus corresponds to thickness D.sub.1 of the embodiments according to FIGS. 1a and 1b. Thickness D.sub.2 of the sheet metal part, from which the collar is obtained by drawing up, is approximately D.sub.2=0.2 mm.

[0319] Due to the different coefficient of thermal expansion α.sub.3 of the sheet metal part, which is significantly higher than that of the conductor or the glass or glass material, raised collar 40 with bulges 44 as shown in FIGS. 2a and 2b provides sufficient prestress onto conductor 20 for a compression seal. The conductor, sealed into opening 3, as indicated in FIG. 2b, can consist of a ferritic high grade steel with an α.sub.1 of 10 to 11.Math.10.sup.−6 1/K, and the material of the sheet metal part or housing part and collar is a Duplex high grade steel or an austenitic high grade steel with a coefficient of expansion α.sub.3 in the range of 15 to 18.Math.10.sup.−6 1/K.

[0320] Compared to massive plates, the version according to the present invention is characterized by a very thin wall thickness D.sub.2, according to FIGS. 2a and 2b. The expulsion force of conductor 20 is determined by the prestress due to bulge 44 with width W which is applied by the sheet metal part or housing part onto the glass.

[0321] FIG. 3 shows a design wherein housing part 1 includes a flexible flange 310 for an electrical storage device. Flange 310 includes a connecting region 380 which serves to connect the feedthrough or housing part or respectively battery part 1 with opening 3 with the conductor sealed in the glass or glass ceramic material, with a housing, for example a housing of a storage device, as shown in FIG. 5. Connecting of the sheet metal part with opening with the housing can occur by way of welding, in particular laser welding or also soldering. The connection is such, that the He leakage rate is less than 1.Math.10.sup.−6 mbar 1/s at 1 bar pressure difference. The He leakage rate is herewith the same as that for the sealed conductor, and a hermetically sealed housing for a storage device, in particular a battery is thus provided. Due to free space F, which is formed between the raised area, that is edge 300, which is to be equated with the raised collar according to the embodiment according to FIGS. 2a to 2b, which provides seal length EL and connecting region 380, pressures acting on the glass material can be reliably compensated. The flexibility of flange 310 prevents—for example on temperature fluctuations—braking of the glass. In particular, the flexibility of flange 310 avoids any tensile and compressive stresses that might be caused, for example by laser welding. Tensile and compressive stresses can thus be absorbed. In the current example, seal length EL is provided by a sheet metal part having a thickness D.sub.2 of, for example 0.2 mm and a width W, which is pressed down and subsequently reshaped into a flexible flange, as illustrated in FIGS. 1a and 1b. Sealing takes place into opening 3 of the housing part. The region of the housing part which applies the prestress to the glass material is identified with 300. Width W of the flexible flange provides the prestress which is applied onto the glass material. As shown in FIG. 3, width W of the flexible flange extends beyond the wall thickness of the sheet metal section in which sealing takes place and into the region of the flexible flange.

[0322] The housing part, optionally the sheet metal part is in particular a part of a housing of an electrical storage device, in particular a battery cover. Laser welding of the illustrated housing part 1 to the rest of the housing occurs at tip 302 of flexible flange 380. In the region of tip 302, the thickness of the flange is weakened and is only 0.15 mm instead of, for example, 0.2 mm for the sheet metal part. Flange 380 of the housing part with opening or respectively feedthrough, which is weakened in the region of tip 302, can be connected directly with a remaining housing of the electrical storage device, resulting in the electrical storage device. Due to laser welding, the entire component, including the glass or glass ceramic material, is heated. In feedthroughs without compression seals, the feedthrough, in other words the glass and/or glass ceramic material, could come loose, and the feedthrough would leak. This is avoided in a compression seal. The housing of the storage device includes a housing part with opening or respectively a feedthrough according to the present invention. Since the feedthrough or respectively the housing part with the opening is very compact due to the very thin material thickness D.sub.2 of only 0.1 mm to 1 mm of the housing part or respectively the battery cover, a very compact storage device, in particular a microbattery can be provided when such a sheet metal part is installed as part of a feedthrough in a battery housing, for example by welding in the area of the tip 302 of the flexible flange to the rest of the housing of the storage device.

[0323] FIG. 4 shows flexible flange 380 in detail. The same components as in FIG. 3 are assigned the same reference numbers. FIG. 4 does not show the width of the flexible flange as in FIG. 3, but instead shows thickness D.sub.E, that is, the wall thickness of the sheet metal section into which the sealing takes place. Wall thickness D.sub.E can be compared with sheet thickness D.sub.2 of the second section; here too, according to the present invention, width W is greater than wall thickness D.sub.E.

[0324] FIG. 5 shows an arrangement of an embodiment of the present invention with flexible flange 1380, wherein flexible flange 1380 for wall thickness has the same thickness as the sheet metal part, namely D.sub.2. Flexible flange 1380 is obtained by bending the sheet metal with thickness D.sub.2. The flexible flange includes a collar which is also formed by bending, into which the sealing takes place. As shown in FIG. 5, width W extends from the region of the ring in which sealing into glass material 22 occurs, to the region of flexible flange 1380 analogous to FIG. 3. If the flexible flange is made of a ferritic material, prestressing is not sufficient to provide a reliable compression seal, especially in the case of thin wall thicknesses of the metal sheet section in which sealing occurs, since in such a case prestressing is not sufficient.

[0325] In order to provide such a compression seal, especially with steel as material, a wall thickness D.sub.Wall would be necessary over the entire seal length EL, as shown in FIG. 6, which essentially corresponds to width W. This large wall thickness of the metal ring is required to exert a permanent prestress on the glass. As can be seen from FIG. 6, wall thickness D.sub.Wall is significantly greater than metal sheet thickness D.sub.2. The steel, in particular the mild steel, has a coefficient of expansion in the range 12 to 13.Math.10.sup.−6 K.sup.−1.

[0326] Surprisingly, it has been shown that when using an austenitic high grade steel material with a thermal coefficient of expansion α in range of 16 to 18.Math.10.sup.−6 K.sup.−1 or a Duplex high grade steel material with a thermal coefficient of expansion α in the range of 13 to 14.Math.10.sup.−6 K.sup.−1, it is possible to provide a secure compression seal with sufficient prestress force if a pressure is not applied over the entire seal length EL as shown in FIG. 6, but instead only over a reduced seal length EL.sub.reduced, which substantially corresponds to sheet metal thickness D.sub.2 of the sheet metal part, as shown in FIG. 7. Same components from FIG. 5 and FIG. 6 are identified with the same reference numbers. Width W of the region which applies the pressure upon the glass material is shown in FIG. 5 and FIG. 6 and extends into the region of the flexible flange. It is, however, disadvantageous that, due to the high pressure of the austenitic material in the region of the pressure seal which—as shown in FIG. 6—is a raised seal, fissures appear in the glass material.

[0327] For a compression seal with a design with flex-flange 1380 according to FIGS. 5, 6 and 7, a deep-set compression seal is thus advisable. This would result in fewer glass fissures. This is achieved by use of a Duplex high grade steel in the form of a deep-set compression seal. With the Duplex material, the prestress on the glass is less than when using austenitic high grade steel, and thus also the differential pressure between the prestress and the external glass zone, resulting in that the risk of glass fissures is reduced.

[0328] With the selection of the various ring materials or respectively materials for the flex-flange into which sealing occurs, the expulsion force of the pin or conductor can be influenced by the different glass pre-stresses which act via the glass also upon the pin or conductor. This influence can be used to set a safety vent function of the pin or conductor, in other words, opening of the battery in the event of battery overpressure in the case of damage.

[0329] Additional control possibilities to influence the opening force of the sealed in pin or conductor, would be to change the thickness of the seal, use of different glass materials, use of glass materials with different bubble content in the glass, structuring of the glass surface through the shape of the glass part prior to sealing, structuring of the glass surface through the shape of the glass part during sealing, structuring of the glass surface through laser treatment after sealing. Structuring of the glass surface can occur, for example, through introduction of one or several notches and/or taper.

[0330] Such a safety vent function can also be achieved by notches and/or tapers of the sealed-in pin and/or the base body. The aforementioned measures can be carried out individually or in combination. The introduction of structuring, especially of notches and/or tapers can occur on one side of the housing part or base body with a top and bottom side in the glass, housing part and/or conductor, or on both sides, in other words on the top side as well as the bottom side, that is on both sides.

[0331] The advantage of structuring the glass material for a safety vent function is, that the glass as a formed body is precisely dimensioned, so that the trigger point of the safety vent function can be regulated very precisely. It is optional, if for the safety vent function a groove is introduced into the glass material by way of laser. It is then possible, independently of the glass density and/or thickness of the base body, therefore of the ring thickness, to specifically set an expulsion force for the conductor and thus the trigger point.

[0332] The ejection force or expulsion force for the conductor can also be influenced by the length of the seal and/or the formation of menisci.

[0333] With the aid of the safety vent function of the conductor, it is possible in particular to set an opening of a storage device, in particular a battery in the event of overpressure in case of damage.

[0334] In addition to the previously described measures, the expulsion force and thus the safety vent function of the conductor can be adjusted through one or several of the measures described below:

[0335] Thickness of seal;

[0336] Use of different glass materials;

[0337] Different bubble content in glass;

[0338] A structured glass surface through the shape of the glass part prior to sealing;

[0339] A structured glass surface through the shape of the glass part during sealing;

[0340] A structured glass surface through laser treatment after sealing;

[0341] Notches or tapers in glass material, on one or both sides;

[0342] Length of seal and formation of menisci.

[0343] FIG. 8 shows an electrical device according to the present invention, especially a microbattery with an inventive feedthrough or respectively housing part with an opening. The electrical device or respectively microbattery is identified with reference number 10000. The feedthrough or respectively the housing part with opening 1 is designed as in FIG. 3 and FIG. 4. Same components of the feedthrough as in FIG. 3 and FIG. 4 are identified with the same reference numbers in FIG. 5. The battery cover with sheet metal part 1 and flexible flange according to FIGS. 3 and 4 is tightly connected in region 1504 as part of the housing, with a weakened protrusion 10001 with remaining flange 10001 of the housing of the electrical device or respectively the microbattery by way of welding, in particular laser welding. A terminal lug 1400 is connected to conductor 20 which is sealed into opening 3 of the feedthrough in a glass material 22. The battery in housing 10010 is electrically connected via terminal lug 1400, which protrudes into housing 10010. The pressure-tight connection of the housing cover with opening 3 as part of the feed-through with the rest of the housing of the battery, which is designed in cylindrical form and directly adjoins the feed-through, can be made by welding. The welding occurs optionally between the sheet metal part with opening as part of the feedthrough and the optionally cylindrical housing part which accommodates the battery in the region of tip 1504 of the sheet metal part. The height of the region welded to the tip 1504 is at most 5 mm, optionally at most 3 mm, in particular it is in the range 1 mm to 5 mm and determines the height of the microbattery. Pressure-tight means that the He leakage rate is less than 10.sup.−8 mbar l/sec at 1 bar pressure difference. Due to the flexible flange, which is designed as shown in FIGS. 3 and 4, sufficient elasticity is achieved even after welding of the feedthrough in the housing or respectively with the remaining housing part and the therefrom resulting temperature effect. To isolate the flexible flange from inner conductor 20, the feedthrough shown in FIG. 5 includes an isolation ring 10030 made for example of a glass material, covering seal 22, and the flexible flange consisting of metal.

[0344] Due to the compact feedthrough the height of the entire microbattery is 5 mm at most, optionally no more than 3 mm, in particular in the range of 1 mm-5 mm. The dimensions in the region of the sheet metal part as a part of the feedthrough with flexible flange according to FIGS. 3 and 4 are as follows. The diameter of conductor 20 is 1 mm to 2 mm, optionally 1.5 mm. The diameter of opening 3 is in the range of 1 mm to 4 mm, optionally 2.5 mm to 3.0 mm. In the current example, an insulation is achieved between terminal lug 1400 and the sheet metal part of the feedthrough by way of insulation ring 10030. Alternatively to an insulation ring, effervescent glass can also be used, for example. The area covered by the glass material for insulation is in the range of 0.2 mm. The width of the entire sheet metal part as part of the feedthrough which is introduced into the housing is between 4.0 mm and 6.0 mm, optionally 4.5 mm. The embodiment according to FIG. 5 is characterized in that a surface of a partial surface 1052 of the housing part is covered by an inorganic material, in particular a glass material or a glass ceramic material, in order to provide an electrical insulation for example, for a 1400 terminal lug with respect to the housing in the case of the introduced feedthrough.

[0345] Whereas FIG. 8 shows the contacting of a conductor inside the microbattery by way of a bent terminal lug 1400, as shown in FIG. 8, FIG. 9a shows a conductor with an external connection. Conductor 20 includes a head or terminal head 20000 arranged on the conductor and consisting of a metallic material, optionally the same material as the conductor. The head is optionally round with a diameter in the range of 8 to 15 mm. The diameter of the conductor which is generally round is in the range of 4 mm to 8 mm. The diameter of the opening is 6 mm to 10 mm. The sealed in conductor 20 is connected to an electrical device not shown, with connecting head 20000 consisting of a metallic material. Optionally, the conductor and connecting head 20000 are integral, in other words, the connecting head can be obtained by expansion during pressing. To prevent a short circuit between connecting head 20000 of conductor 20 and sealing ring 10 of the battery cover, which also consists of a metallic material, an insulating element, in particular an insulating washer 20010, optionally made of a glass or glass-ceramic material, a ceramic or a non-conductive organic material, is provided.

[0346] FIG. 9b again shows a housing part with sealing ring 10 and sealed-in conductor 20 with terminal head 20000 and insulating washer 20010. It can be clearly seen that insulating washer 20010 extends to conductor 20 and electrically insulates the entire terminal head 20000 from sealing ring 10. The same components as in FIG. 6a are identified with the same reference numbers.

[0347] FIG. 9c shows is top view of sealing ring 10 in a round shape with a sealed-in conductor with connection head 20000. As can be seen from FIG. 9c, connecting head 20000 covers between 60% and 90%, optionally 70% to 85%, of the area of the opening of sealing ring 10. Sealing ring 10 is equivalent to the previously described housing part with opening, that is, the sealing ring has a coefficient of expansion α.sub.3 which is always greater than the coefficient of expansion α.sub.2 of the glass material. Sealing ring 10 can also be referred to as the base body into which sealing occurs. FIGS. 10a to 10b show in detail sealing of a conductor 20 into an opening 3 of a housing part, in particular a base body, optionally a sealing ring 9, as illustrated in FIG. 1b. In the arrangement according to FIG. 10a, the sealing takes place over a longer length than in FIG. 10b, so that no meniscus is formed from the glass or glass ceramic material to the housing part, in particular the base body, optionally sealing ring 9. The design of a seal without meniscus results in that practically no fractures occur in the glass material. Furthermore, a high expulsion force of the sealed-in conductor is provided.

[0348] In contrast, FIG. 10b shows an embodiment of the present invention in which a meniscus is formed in the glass material to the housing part or base body or sealing ring 9. The meniscus is identified by reference number 30000, the glass or glass ceramic material by reference number 22. The meniscus is formed because the seal length is short compared to FIG. 9a. When sealing with a meniscus, the number of fractures increases compared to the case where no meniscus is formed in the glass material. The formation of a meniscus greatly reduces the expulsion resistance of the sealed in metal pin, in particular the conductor, compared with sealing without a meniscus. In summary, it can be stated that sealing, whereby the formation of a meniscus is avoided, on the one hand reduces the probability of glass breakage and on the other hand increases the expulsion resistance. In general, the thinner the base body in which sealing occurs, the stronger the effect of the meniscus. In general, the longer the seal length, the higher the expulsion forces since no meniscus is then formed.

[0349] The feedthrough according to the present invention is used in particular for housings of electrical storage devices, in particular batteries or capacitors. With very flat feedthroughs according to the present invention for an electrical storage device, an electrical storage device can be provided having a maximum height of 5 mm.

[0350] By compression sealing the conductor into the glass material a hermetically sealed feedthrough is provided.

[0351] In particular, in the use of a flex-flange design in a compression seal a greater pin or conductor contact pressure is achieved, in particular when using Duplex high grade steel or austenitic steel. The flex-flange design as a compression seal is moreover mechanically more reliable and displays greater expulsion forces for the sealed-in conductor than conventional seals.

[0352] While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.