Case 2:20-cv-00054-JRG Document 1-4 Filed 02/24/20 Page 1 of 13 PageID #: 57
`Case 2:20-cv-00054-JRG Document 1-4 Filed 02/24/20 Page 1 of 13 PageID #: 57
`
`EXHIBIT D
`
`EXHIBIT D
`
`

`

`Case 2:20-cv-00054-JRG Document 1-4 Filed 02/24/20 Page 2 of 13 PageID #: 58
`I lllll llllllll Ill lllll lllll lllll lllll lllll 111111111111111111111111111111111
`US009799858B2
`
`c12) United States Patent
`Gaugler
`
`(10) Patent No.:
`(45) Date of Patent:
`
`US 9,799,858 B2
`Oct. 24, 2017
`
`(54) BUTTON CELL HAVING WINDING
`ELECTRODE AND METHOD FOR THE
`PRODUCTION THEREOF
`
`(75)
`
`Inventor: Winfried Gaugler, Ellwangen (DE)
`
`(73) Assignee: VARTA Microbattery GmbH (DE)
`( * ) Notice:
`
`Subject to any disclaimer, the term ofthis
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`(21) Appl. No.:
`
`13/378,117
`
`(22) PCT Filed:
`
`Jun. 18, 2010
`
`(86) PCT No.:
`
`PCT /EP2010/058637
`
`§ 371 (c)(l),
`(2), ( 4) Date: Dec. 14, 2011
`
`(87) PCT Pub. No.: W02010/146154
`PCT Pub. Date: Dec. 23, 2010
`
`(65)
`
`Prior Publication Data
`
`US 2012/0100406 Al
`
`Apr. 26, 2012
`
`(30)
`
`Foreign Application Priority Data
`
`Jun. 18, 2009
`Dec. 31, 2009
`
`(DE) ........................ 10 2009 030 359
`(DE) ........................ 10 2009 060 800
`
`(51)
`
`Int. Cl.
`HOJM 4100
`HOJM 2102
`
`(2006.01)
`(2006.01)
`(Continued)
`
`(52) U.S. Cl.
`CPC ....... HOJM 210222 (2013.01); HOJM 210413
`(2013.01); HOJM 210439 (2013.01);
`(Continued)
`
`(58) Field of Classification Search
`CPC ........... H01M 2/0439; H01M 10/0587; HOlM
`10/0525; H01M 2/0413; H01M 2/0222;
`(Continued)
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`3,827,916 A
`3,960,599 A
`
`8/1974 Fagan, Jr.
`6/1976 Reynier et al.
`(Continued)
`
`FOREIGN PATENT DOCUMENTS
`
`CN
`DE
`
`4/2010
`201440429
`5/1969
`1 471 758
`(Continued)
`
`OTHER PUBLICATIONS
`
`English language machine translation of JP 2008-262825.*
`(Continued)
`
`Jonathan Jelsma
`Primary Examiner -
`Assistant Examiner - Omar Kekia
`(74) Attorney, Agent, or Firm - DLA Piper LLP (US)
`
`(57)
`
`ABSTRACT
`
`A button cell includes a housing consisting of two metal
`housing halves, an electrode separator assembly in the form
`of a preferably spiral-shaped winding inside the housing,
`and metal conductors which electrically connect the elec(cid:173)
`trodes of the assembly to the housing halves, wherein at least
`one of the conductors is connected to the respective housing
`half by welding.
`
`9 Claims, 5 Drawing Sheets
`
`

`

`Case 2:20-cv-00054-JRG Document 1-4 Filed 02/24/20 Page 3 of 13 PageID #: 59
`
`US 9,799,858 B2
`Page 2
`
`(51)
`
`(52)
`
`(58)
`
`(2006.01)
`(2006.01)
`(2006.01)
`(2006.01)
`(2010.01)
`(2010.01)
`
`Int. Cl.
`HOlM 2104
`HOlM 2106
`HOlM 2126
`HOlM 10104
`HOlM 1010587
`HOJM 1010525
`U.S. Cl.
`CPC ............. HOlM 2106 (2013.01); HOlM 21263
`(2013.01); HOlM 1010427 (2013.01); HOlM
`1010436 (2013.01); HOlM 1010587 (2013.01);
`HOJM 210227 (2013.01); HOJM 1010525
`(2013.01); YJOT 2914911 (2015.01)
`Field of Classification Search
`CPC .... HOlM 10/0436; HOlM 2/06; HOlM 2/263;
`HOlM 2/0465; HOlM 2/0227; YlOT
`29/4911
`USPC ............. 429/1-11, 47-255; 29/623.1-623.5;
`219/121.64
`See application file for complete search history.
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`5/1978 Merritt, Jr.
`4,091,181 A
`9/1980 Ishida et al.
`4,220,695 A
`9/1980 Nakayama
`4,224,387 A
`12/1984 Koga
`4,487,819 A
`9/1985 Crabtree
`4,539,271 A
`5/1990 Ashihara et al.
`4,927,719 A
`12/1993 Y amahira et al.
`5,273,842 A
`10/1994 Kita et al.
`5,356,736 A
`10/1996 Oltman et al.
`5,567,538 A
`2/1997 Marincic et al.
`5,603,737 A
`5/1997 Zhong et al.
`5,631,104 A
`12/1997 Xue et al.
`5,698,340 A
`8/1998 Mitate et al.
`5,792,574 A
`512000 Brenner
`6,066,184 A
`11/2000 Votz et al.
`6,143,440 A
`6/2001 Oltman
`6,245,452 Bl
`6,265,100 Bl*
`7/2001 Saaski et al. ................. 429/163
`8/2001 Omaru et al.
`6,277,522 Bl
`912002 Cantave et al.
`6,443,999 Bl
`212009 Tsukamoto et al.
`7,488,553 B2
`712009 Suzuki et al.
`7,566,515 B2
`200110009737 Al *
`7/2001 Lane ............................. 429/174
`3/2002 Inoue et al.
`2002/0034680 Al
`12/2002 Yoshimura et al.
`2002/0192559 Al
`112003 Kaun
`2003/0013007 Al
`212004 Miyaki
`2004/0029004 Al
`3/2004 Omaru
`2004/0048160 Al
`6/2004 Haug et al.
`2004/0110061 Al
`3/2005 Kano et al.
`2005/0058904 Al
`8/2005 Miyaki
`2005/0181276 Al
`2005/0271938 Al* 12/2005 Suzuki et al . ................ 429/185
`
`2008/0003500 Al*
`2008/0318126 Al
`2009/0325062 Al
`2010/0227217 Al
`2011/0091753 Al
`2011/0200871 Al
`2012/0015224 Al
`2012/0028110 Al
`2012/0100406 Al
`2013/0130066 Al
`2013/0216881 Al
`
`112008 Issaev et al. .................. 4291200
`12/2008 Ishii
`12/2009 Brenner et al.
`912010 Fujikawa et al.
`412011 Wang et al.
`8/2011 Pytlik et al.
`112012 Pytlik et al.
`212012 Brenner
`412012 Gaugler
`512013 Pytlik et al.
`8/2013 Gaugler et al.
`
`FOREIGN PATENT DOCUMENTS
`
`DE
`DE
`DE
`DE
`DE
`DE
`DE
`EP
`EP
`EP
`EP
`EP
`EP
`GB
`GB
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`JP
`WO
`
`31 13 309 Al
`36 38 793 Al
`196 47 593 Al
`697 00 312
`198 57 638
`10 2009 008 859 Al
`10 2009 017 514 Al
`0 202 857
`1 318 561 Al
`1 339 115 Al
`1 372 209 Al
`1 808 916 Al
`1 968 134
`1088271
`2 110 464
`1-307176
`H05-121056
`7-153488
`8-293299
`11-345626 A
`11-354150 A
`2000-77040
`2002-352789
`2003-31266
`2004-158318
`3902330 B2
`2007-200683
`2007-294111 A
`2008-251192
`2008-262825
`2008-262825 A
`2008-262826
`2010/089152 Al
`
`10/1982
`5/1988
`5/1998
`212000
`612000
`8/2010
`10/2010
`7 /1991
`6/2003
`8/2003
`12/2003
`7/2007
`9/2008
`10/1967
`6/1983
`12/1989
`5/1993
`6/1995
`1111996
`12/1999
`12/1999
`3/2000
`12/2002
`112003
`6/2004
`4/2007
`8/2007
`1112007
`10/2008
`* 10/2008
`10/2008
`10/2008
`8/2010
`
`............ HOlM 10/36
`
`OTHER PUBLICATIONS
`
`US Official Action dated Mar. 27, 2014 from related U.S. Appl. No.
`13/146,669.
`US Official Action dated Sep. 2, 2014 from related U.S. Appl. No.
`13/146,669.
`Linden, D. et al., "Handbook of Batteries," 2002, Third Edition, The
`McGraw-Hill Companies, Inc., Sections 11.4, 11.4.1, 14.1, 14.5.2,
`14.8and14.8.2, and Figs. 11.2, 11.5, 14.38, 34.13, 35.30 and35.32.
`* cited by examiner
`
`

`

`Case 2:20-cv-00054-JRG Document 1-4 Filed 02/24/20 Page 4 of 13 PageID #: 60
`
`U.S. Patent
`
`Oct. 24, 2017
`
`Sheet 1 of 5
`
`US 9,799,858 B2
`
`iOS
`108 110 l
`l
`.~
`ll
`/
`l
`/
`
`112
`,/
`
`~·.-r,.. _, .. ,'""l .. ,. .. ,., ...... .
`
`. i
`.i
`164 ~ns
`
`Fig. 1 A
`
`~n2
`l
`l
`1
`
`.· ~ ....
`
`102 no
`i
`f,l
`/
`...
`I
`1
`
`,: .;.:
`
`.·
`
`,
`
`

`

`Case 2:20-cv-00054-JRG Document 1-4 Filed 02/24/20 Page 5 of 13 PageID #: 61
`
`U.S. Patent
`
`Oct. 24, 2017
`
`Sheet 2 of 5
`
`US 9,799,858 B2
`
`Fig. 2A
`
`203
`
`Fig. 28
`
`Fig. 2C
`
`Anode
`
`

`

`Case 2:20-cv-00054-JRG Document 1-4 Filed 02/24/20 Page 6 of 13 PageID #: 62
`
`U.S. Patent
`
`Oct. 24, 2017
`
`Sheet 3 of 5
`
`US 9,799,858 B2
`
`306
`\
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`
`1' ............ ---;::
`
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`Y~ . ~"""',....¢:!::::::::::· ': "'1\{ · .
`I.~~,.~-~-.:·.· -. i
`r ..
`c~,:;t
`·,1~·
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`l~*··
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`3~3 3081 f-3()5
`. . l
`i
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`
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`Fig .. 3A
`
`t l
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`306
`
`309
`
`Fig. 3B
`
`

`

`Case 2:20-cv-00054-JRG Document 1-4 Filed 02/24/20 Page 7 of 13 PageID #: 63
`
`U.S. Patent
`
`Oct. 24, 2017
`
`Sheet 4 of 5
`
`US 9,799,858 B2
`
`Fig. 4A
`
`Fig. 48
`
`

`

`Case 2:20-cv-00054-JRG Document 1-4 Filed 02/24/20 Page 8 of 13 PageID #: 64
`
`U.S. Patent
`
`Oct. 24, 2017
`
`Sheet 5 of 5
`
`US 9,799,858 B2
`
`Fig. 5
`
`

`

`Case 2:20-cv-00054-JRG Document 1-4 Filed 02/24/20 Page 9 of 13 PageID #: 65
`
`US 9,799,858 B2
`
`1
`BUTTON CELL HAVING WINDING
`ELECTRODE AND METHOD FOR THE
`PRODUCTION THEREOF
`
`RELATED APPLICATIONS
`
`This is a §371 of International Application No. PCT/
`EP2010/058637, with an international filing date of Jun. 18,
`2010 (WO 2010/146154 A2, published Dec. 23, 2010),
`which is based on German Patent Application Nos. 10 2009
`030 359.6, filed Jun. 18, 2009, and 10 2009 060800.1, filed
`Dec. 31, 2009, the subject matter of which is incorporated by
`reference.
`
`TECHNICAL FIELD
`
`This disclosure relates to button cells having a housing
`consisting of two metal housing halves, which contains a
`wound electrode separator assembly, and to a method for its
`production.
`
`BACKGROUND
`
`Button cells conventionally comprise a housing consist(cid:173)
`ing of two housing halves: a cell cup and a cell top. These 25
`may, for example, be produced as stamped parts from
`nickel-plated deep-drawn sheet metal. Usually, the cell cup
`is positively poled and the housing top negatively poled. The
`housing may contain a very wide variety of electrochemical
`systems, for example, zinc/Mn02 , primary and secondary 30
`lithium systems, or secondary systems such as nickel/cad(cid:173)
`mium or nickel/metal hydride.
`The liquid-tight closure of button cells is conventionally
`carried out by crimping the edge of the cell cup over the edge
`of the cell top, in combination with a plastic ring which is 35
`arranged between the cell cup and the cell top and is used
`simultaneously as a sealing element and for electrical insu(cid:173)
`lation of the cell cup and the cell top. Such button cells are
`described, for example, in DE 31 13 309.
`As an alternative, however, it is also possible to manu- 40
`facture button cells in which the cell cup and the cell top are
`held together in the axial direction exclusively by a force-fit
`connection, and which correspondingly do not have a
`crimped cup edge. Such button cells and a method for their
`production are described in unpublished German patent 45
`application 10 2009 017 514.8. Regardless of the various
`advantages which such button cells without crimping may
`present, they nevertheless cannot withstand such high
`stresses in the axial direction as comparable button cells
`with a crimped cup edge, especially as regards axial 50
`mechanical loads which originate from inside the button
`cell. For example, the electrodes of rechargeable lithium ion
`systems are constantly subjected to volume changes during
`charging and discharging processes. In button cells without
`crimping, the axial forces occurring in this case can naturally 55
`cause leaks more easily compared with button cells with
`crimping.
`A solution to this problem may be found in unpublished
`German patent applications 10 2009 030 359.6 and 10 2009
`008 859.8. Inter alia, references may be found therein to 60
`button cells comprising a housing having a plane bottom
`region and a plane top region parallel thereto, an assembly
`consisting of flat electrode layers and separator layers in the
`form of a preferably spiral-shaped electrode winding being
`arranged in the housing in such a way that the end sides of 65
`the winding face in the direction of the plane bottom region
`and the plane top region. The electrode layers of the winding
`
`2
`are thus oriented essentially orthogonally to the plane bot(cid:173)
`tom and top regions of the housing. As a result of this, radial
`forces such as occur during the aforementioned charging and
`discharging processes oflithium ion systems can in principle
`5 be absorbed better than in the case of conventional lithium
`ion button cells, in which electrode layers are arranged
`stacked in parallel alignment with the plane bottom and top
`regions.
`Windings consisting of flat electrode layers and separator
`10 layers can be produced quite straightforwardly using known
`methods (see, for example, DE 36 38 793) by the electrodes
`being applied, in particular laminated, particularly in the
`form of strips, flat onto a separator provided as an endless
`band. The assembly consisting of the electrodes and sepa-
`15 rators is generally wound on a so-called "winding mandrel."
`After the winding has been removed from the winding
`mandrel, an axial cavity is left at the center of the winding,
`the effect of which is that the winding may possibly expand
`into this cavity. This, however, can sometimes lead to
`20 problems in the electrical contact of the electrodes with the
`metal housing halves.
`It could therefore be helpful to provide a button cell in
`which the aforementioned problems do not occur, or only
`occur to a greatly reduced extent.
`
`SUMMARY
`
`I provide a button cell including two metal housing halves
`separated from one another by an electrically insulating seal
`forming a housing having a plane bottom region and a plane
`top region parallel thereto, an electrode separator assembly
`including at least one positive electrode and at least one
`negative electrode inside the housing, the assembly provided
`in the form of a winding, end sides of which face in a
`direction of the plane bottom region and the plane top
`region, and metal conductors electrically connected to the at
`least one positive electrode and the at least one negative
`electrode, respectively, to one of the housing halves, wherein
`at least one of the conductors is connected to the respective
`housing half by welding wherein weld beads and/or weld
`spots pass through the housing.
`I also provide a method for producing button cells includ(cid:173)
`ing (a) providing a first and a second metal housing half, (b)
`placing an electrode separator assembly including a positive
`electrode and a negative electrode in one of the housing
`halves, wherein a metal conductor bonded to at least one of
`the electrodes, ( c) assembling the two housing halves, and,
`subsequently, ( d) laser welding at least one of the conductors
`to the inner side of one of the metal housing halves.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIGS. lA and lB schematically show a cross section of a
`preferred example of a button cell 100.
`FIGS. 2A to 2C schematically show selected assembly
`steps of the button cell of FIG. 1.
`FIGS. 3A and 3B schematically show selected views of
`windings of the button cell.
`FIGS. 4A and 4B schematically show two different welds.
`FIG. 5 shows microphotographs of a weld from top and
`cross-sectional views.
`
`DETAILED DESCRIPTION
`
`My button cell always comprises two metal housing
`halves separated from one another by an electrically insu(cid:173)
`lating seal and forming a housing having a plane bottom
`
`

`

`Case 2:20-cv-00054-JRG Document 1-4 Filed 02/24/20 Page 10 of 13 PageID #: 66
`
`US 9,799,858 B2
`
`10
`
`3
`region and a plane top region parallel thereto. As mentioned
`in the introduction, the two housing halves are generally a
`so-called "housing cup" and a "housing top." In particular,
`nickel-plated steel or sheet metal are preferred as the mate(cid:173)
`rial for the housing halves. Trimetals, in particular, are
`furthermore suitable as the metallic material, for example,
`ones comprising the sequence nickel, steel (or stainless
`steel) and copper (in which case the nickel layer preferably
`forms the outer side of the button cell housing and the
`copper layer preferably forms the inner side).
`As the seal, it is, for example, possible to use an injection(cid:173)
`molded seal or a film seal. The latter are described, for
`example, in DE 196 47 593.
`At least one positive electrode and at least one negative 15
`electrode are arranged inside the housing, specifically each
`in the form of flat electrode layers. The electrodes are
`preferably connected to one another by at least one flat
`separator. The electrodes are preferably laminated or adhe(cid:173)
`sively bonded onto this separator. The electrodes and the 20
`separator generally each have a thickness only in the µm
`range. A porous plastic film is generally used as the sepa(cid:173)
`rator.
`This assembly is provided in the form of a winding,
`particularly in the form of a spiral-shaped winding, in the 25
`housing of a button cell, the winding being arranged such
`that its end sides face in the direction of the plane bottom
`region and the plane top region of the housing. Full refer(cid:173)
`ence is hereby made to the description of such windings, and
`button cells comprising such windings, in unpublished Ger- 30
`man patent applications DE 10 2009 030 359.6 and DE 10
`2009 008 859.8 already mentioned above. All the preferred
`forms described in those applications are also intended to
`apply for the button cell described here and the electrode
`winding described here.
`Besides the housing halves and the electrode separator
`assembly, my button cell always also comprises metal
`conductors which electrically connect the at least one posi(cid:173)
`tive electrode and/or the at least one negative electrode
`respectively to one of the housing halves. The conductor or 40
`conductors connected to the at least one positive electrode
`preferably consist of aluminum. The conductors connected
`to the at least one negative electrode preferably consist of
`nickel or copper.
`On the electrode side, the conductors are preferably 45
`connected to current collectors. The latter are generally
`metal foils or meshes conventionally coated on both sides
`with active electrode material. These current collectors
`preferably consist of aluminum on the side of the positive
`electrode, and preferably nickel or copper on the side of the
`negative electrode. The foils or meshes have, in particular,
`thicknesses of between 1 µm and 100 µm. The connecting of
`the conductors to the current collectors is preferably carried
`out by welding.
`Particularly in respect of preferred forms of the electrode 55
`separator assembly arranged in my button cell, reference is
`made to DE 10 2009 030 359.6 and DE 10 2009 008 859.8.
`These disclose in particular preferred layer sequences and
`layer thicknesses for electrodes and separators, for example,
`an assembly comprising the layer sequence:
`negative electrode/separator/positive electrode/separator
`or
`positive electrode/separator/negative electrode/separator.
`Assemblies comprising the layer sequences:
`negative electrode/separator/positive electrode/separator/ 65
`negative electrode
`or
`
`4
`positive electrode/separator/negative electrode/separator/
`positive electrode
`may also be preferred. In these, the assembly therefore
`comprises more than one positive electrode and/or more
`than one negative electrode.
`Particularly preferably, at least one of the electrodes of a
`button cell is a lithium intercalation electrode. The button
`cell is preferably a lithium ion battery, in particular a
`secondary lithium ion battery.
`My button cell is distinguished particularly in that at least
`one of the conductors is welded to the respective housing
`half, preferably both the conductor connected to the at least
`one positive electrode and the conductor connected to the at
`least one negative electrode.
`As has already been mentioned in the introduction, par(cid:173)
`ticularly in the case oflithium ion button cells the electrodes
`are subject to volume changes during a charging-discharging
`cycle, as a result of which contact problems may arise
`between the conductors and the housing halves. Such con(cid:173)
`tact problems no longer apply when the conductors are
`welded to the respective housing halves.
`Particularly preferably, the conductor or conductors are
`welded onto the inner side of the housing in the plane bottom
`region or the plane top region, respectively, of the housing.
`For this purpose, according to conventional methods the
`welding process must be carried out before the housing is
`assembled, which is very difficult to achieve in terms of
`production technology. Welded connections have therefore
`been regarded as highly disadvantageous for bonding the
`conductors to the inner side of the housing halves. By virtue
`of my method as described in more detail below, however,
`a solution can be provided which also has great advantages
`in terms of production technology.
`By the welding, the at least one positive electrode and/or
`35 the at least one negative electrode are thus connected by one
`or more conductors directly to the plane bottom region or to
`the plane top region of the housing of a button cell, the
`housing top generally being poled negatively and the hous-
`ing cup positively.
`The button cell is preferably a conventional button cell
`having a circular plane bottom region and a circular plane
`top region. In some cases, the button cell may nevertheless
`have an oval configuration. It is, however, important that the
`ratio of height to diameter is preferably always less than 1.
`Particularly preferably, it is between 0.1 and 0.9, in particu(cid:173)
`lar between 0.15 and 0.7. The height is in this case intended
`to mean the shortest distance between the plane bottom
`region and the plane top region parallel thereto. The diam(cid:173)
`eter means the maximum distance between two points on the
`50 lateral region of the button cell.
`Preferably, the conductors of a button cell are flat con(cid:173)
`ductors, in particular metal foils, particularly preferably
`rectangular, strip- or band-shaped metal foils. The foils
`preferably have thicknesses of between 5 µm and 100 µm.
`The conductors are preferably separate components
`bonded, in particular welded, to the electrodes, in particular
`to the current collectors in the electrodes. As an alternative,
`however, the conductors may also be uncoated sections of a
`current collector (sections which are free of active electrode
`60 material), in particular the uncoated ends of such a current
`collector. By bending these uncoated sections, in particular
`these uncoated ends, for example, through 90°, these ends
`can be connected to the bottom or top region of a button cell.
`There, the connecting is preferably carried out by welding.
`Preferably, at least one subsection of the conductor or
`conductors bears flat on the inner side of the housing half or
`halves in the bottom and/or top region of the housing, in
`
`

`

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`US 9,799,858 B2
`
`5
`6
`particular when the conductors are flat conductors such as
`The method is distinguished in particular in that step ( d)
`is carried out after step (c). This means that the at least one
`foils. Such conductors may form a flat layer between the
`conductor is welded to the inner side of the housing when
`inner side of the housing halves and an end side of the
`the housing is closed. The welding must correspondingly be
`electrode winding, and therefore a large-area electrical con(cid:173)
`carried out from the outside through the housing wall of one
`tact with the housing.
`or both housing halves.
`Since in principle both positive and negative electrodes
`Accordingly, I provide button cells which have weld
`may be exposed on the end sides of the electrode winding,
`beads and/or weld spots that pass through the housing, in
`however, it is necessary to avoid a short circuit between the
`particular starting from its outer side.
`electrodes. Particularly preferably, my button cell therefore
`Particularly preferably, the conductor or conductors and
`comprises at least one separate insulating means which 10
`the button cell housing are connected to one another by one
`prevents direct electrical contact between the end sides of
`or more spot-like and/or linear welded connections.
`the winding and the conductors, in particular a subsection of
`Welding the conductors and the housing is preferably
`the conductor or conductors which bears flat on the inner
`carried out by a laser. Its operating parameters must be
`side of the housing halves. Such an insulating means may, 15 adapted as accurately as possible to the thickness of the
`for example, be a film, for example, a plastic adhesive film,
`housing. The power may, for example, be modulated by
`by which the side of the conductor or conductors remote
`varying the pulse frequency. Lastly, the laser should merely
`from the inner side of the button cell housing is covered.
`ensure welding of the housing and conductors while other
`The electrode winding of a button cell may be produced
`components such as the electrode winding should as far as
`by known methods, for example, the method described in
`20 possible not be damaged.
`DE 36 38 793, according to which electrodes and separators
`Suitable lasers are, for example, commercially available
`are wound on a winding mandrel. After the winding has been
`fiber lasers, i.e., solid-state lasers, in which the doped core
`removed from the winding mandrel, there may be an axial
`of a glass fiber forms the active medium. The most common
`cavity at the center of the winding, preferably an essentially
`dopant for the laser-active fiber core is erbium. For high-
`cylindrical axial cavity. In the housing of my button cell,
`25 power applications as in the present case, however, ytter(cid:173)
`such a cavity is delimited laterally by the winding and on the
`bium and neodymium are more preferred.
`end sides by the bottom or top region of the housing,
`Irrespective of the fact that such lasers can be adapted
`respectively, or at least by a subregion thereof. Particularly
`very finely to the respective housing thickness and conduc(cid:173)
`preferably, the at least one conductor is welded to one
`tor dimension, it is nevertheless possible that in certain cases
`housing half or the housing halves in one of these subre(cid:173)
`30 the intensity of the laser will be selected to be too strong and
`gions.
`the laser will penetrate through the housing wall and the
`The axial cavity may optionally contain a winding core,
`conductor. For this reason, welding the conductors to the
`which can prevent the winding from expanding uncon(cid:173)
`housing is particularly preferably carried out in the subre(cid:173)
`trolledly into the cavity.
`gion of the bottom or top region, which delimits the axial
`35 cavity at the center of the winding on the end side. If a laser
`The button cell is in particular a button cell without
`beam penetrates through the housing in this region, the
`crimping, as is described in patent application 10 2009 017
`winding cannot be damaged. Instead, the laser beam will be
`514.8 already mentioned in the introduction. Accordingly,
`absorbed by the housing half lying opposite or by a winding
`there is preferably an exclusively force-fit connection
`core optionally arranged inside the cavity.
`between the housing halves. The button cell thus does not
`If possible, the conductors to be welded should bear as
`have a crimped cup edge, as is always the case with button 40
`cells known from the prior art. The button cell is closed
`flatly as possible on the inner side of the housing. This may,
`without crimping. The content of DE 10 2009 017 514.8 is
`for example, be ensured by fixing the conductors flat by an
`also fully incorporated herein by reference. All the preferred
`adhesive tape onto or at the end sides of an electrode
`forms described in that application is also intended to apply
`winding, before the latter is inserted into the housing.
`for the button cell described here and its housing.
`The aforementioned advantages, and further advantages
`As already mentioned above, welding of conductors to the
`thereof, are in particular also revealed by the description
`inner side of button cell housings is very elaborate in terms
`which now follows of the drawings. In this context, the
`of production technology. I overcome this problem with my
`individual features may be implemented separately or in
`method for producing button cells, which always comprises
`combination with one another. The examples described
`at least the following steps:
`50 merely serve for explanation and better understanding, and
`(a) providing a first and a second metal housing half
`are in no way to be interpreted as restrictive.
`Button cell 100 comprises two metal housing halves: a
`(preferably a cell cup, and a cell top),
`metal cup part 101 and a metal top part 102. With a seal 103
`(b) placing an electrode separator assembly comprising a
`positive electrode and a negative electrode in one of the
`lying between them, the two parts are connected together in
`housing halves (preferably into the cell top), a metal
`55 a leaktight fashion. Together, they form a housing having a
`plane bottom region 104 and a plane top region 105 parallel
`conductor being bonded to at least one of the electrodes
`thereto. In the functional state, these two plane regions 104
`(preferably to all the electrodes),
`and 105 form the poles of the button cell 100, from which
`( c) assembling the two housing halves (preferably by
`current can be drawn by a load. The cell top 102 is inserted
`inserting the cell top into the cell cup), optionally with
`60 into the cell cup 101 so that the lateral surface regions of the
`the provision of separate steps for sealing the housing
`(for example, fitting a seal) and
`cell top and the cell cup overlap, the internal radius of the
`cell cup 101 in the overlap region 106 being essentially
`( d) welding at least one of the conductors to the inner side
`constant in the direction of the rim 107. The edge of the cell
`of one of the metal housing halves.
`101 is thus not crimped. The button cell 100 is therefore an
`The components used in the method, such as the housing
`halves, the conductors and the electrode separator assembly,
`65 uncrimped button cell.
`An assembly 108 of strip-shaped electrodes and strip(cid:173)
`have already been described above. Reference is hereby
`made to the corresponding remarks.
`shaped separators is arranged inside the electrode. The
`
`45
`
`

`

`Case 2:20-cv-00054-JRG Document 1-4 Filed 02/24/20 Page 12 of 13 PageID #: 68
`
`US 9,799,858 B2
`
`8
`and 302 and the end sides 303 and 304 of the electrode
`winding represented. The outer side of the winding is
`protected by the insulating film 307. Ideally, the conductors
`301 and 302 overlap with the openings of the axial cavity
`308 on the end sides, so that welding to the button cell
`housing can be carried out in this region. This can be seen
`clearly in FIG. 3B, as can the winding core 309 which fills
`the axial cavity 308.
`FIGS. 4A and 4B show possible welding variants. For
`example, it is possible to configure the weld bead as a minus
`sign 401 or a plus sign 402 (see the respective enlarged
`representations on the right) so as to indicate the polarity of
`the respective housing half at the same time. The plus sign
`402 is preferably applied on the lower side 404 of a button
`cell, and the minus sign on the upper side 403.
`FIG. 5 shows an enlarged representation of a cross section
`through a housing half 500 of a button cell. The stainless
`steel cup wall 501, the aluminum conductor 502 bearing flat
`underneath and an insulating tape 503 of KAPTON film
`arranged below can be seen. The weld beads 504 and 505,
`which extend from the outer side of the housing inward as
`far as the insulating tape 503 of KAPTON film can be seen
`clearly. The top left image is a plan view of the cutaway
`plane bottom region of the housing half 500. The housing
`half 500 and the conductor 502 have been welded using an
`ytterbium-doped fiber laser of the YLR-400-AC type (manu(cid:173)
`facturing company IPG Photonics Corporation, USA). The
`intensity of the laser was in this case adjusted so that the
`30 insulating tape 503 was not penetrated.
`
`7
`assembly 108 is provided in the form of a spiral-shaped
`winding, the end sides of which face in the direction of the
`plane bottom region 104 and the plane top region 105
`parallel thereto. The assembly is wound on the winding core
`109 at the center of the button cell 100. The winding core is 5
`a hollow plastic cylinder, which partially fills an axial cavity
`at the center of the winding. The cavity itself is delimited
`laterally by the winding and upward and downward by
`corresponding circular sections of the plane cup and top
`regions of the button cell housing. Metal foils 110 and 111, 10
`which act as conductors and are connected to the electrodes,
`bear flat on these regions. These conductors are shielded
`from the end sides of the winding by the insulating elements
`112 and 113. The latter are thin plastic films. The wall
`thickness of the housing in the region of the plane bottom or 15
`top region is generally between 30 µm and 400 µm. The
`thickness of the metal foils 110and111 acting as conductors
`generally lies between 5 µm and 100 µm.
`Welding of the metal foils 110 and 111, acting as con(cid:173)
`ductors, to the respective housing half, which is preferably 20
`done by the schematically represented laser 114, is prefer(cid:173)
`ably carried out in that subregion of the bottom region or of
`the top region of the button cell housing which delimits the
`axial cavity at the center of the winding on the end side. This
`creates a weld bead 115 which passes fully through the 25
`housing of the button cell 100 from