U.S. patent application number 13/968044 was filed with the patent office on 2013-12-12 for glass, in particular solder glass or fusible glass.
This patent application is currently assigned to Schott AG. The applicant listed for this patent is Schott AG. Invention is credited to Linda Johanna Backnaes, Dieter Goedeke.
Application Number | 20130330600 13/968044 |
Document ID | / |
Family ID | 45688430 |
Filed Date | 2013-12-12 |
United States Patent
Application |
20130330600 |
Kind Code |
A1 |
Goedeke; Dieter ; et
al. |
December 12, 2013 |
GLASS, IN PARTICULAR SOLDER GLASS OR FUSIBLE GLASS
Abstract
A glass, for example a glass solder, includes the following
components in mole percent (mol-%): P.sub.2O.sub.5 37-50 mol-%, for
example 39-48 mol-%; Al.sub.2O.sub.3 0-14 mol-%, for example 2-12
mol-%; B.sub.2O.sub.3 2-10 mol-%, for example 4-8 mol-%; Na.sub.2O
0-30 mol-%, for example 0-20 mol-%; M.sub.2O 0-20 mol-%, for
example 12-20 mol-%, wherein M is, for example, K, Cs or Rb;
Li.sub.2O 0-42 mol-%, for example 0-40 mol-% or 17-40 mol-%; BaO
0-20 mol-%, for example 0-20 mol-% or 5-20 mol-%; and
Bi.sub.2O.sub.3 0-10 mol-%, for example 1-5 mol-% or 2-5 mol-%.
Inventors: |
Goedeke; Dieter; (Bad Soden,
DE) ; Backnaes; Linda Johanna; (Landshut,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Schott AG |
Mainz |
|
DE |
|
|
Assignee: |
Schott AG
Mainz
DE
|
Family ID: |
45688430 |
Appl. No.: |
13/968044 |
Filed: |
August 15, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/EP2012/000703 |
Feb 17, 2012 |
|
|
|
13968044 |
|
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Current U.S.
Class: |
429/163 ;
501/14 |
Current CPC
Class: |
Y10T 29/4911 20150115;
Y10T 29/49115 20150115; H01M 2/305 20130101; H01M 10/0569 20130101;
C03C 8/00 20130101; Y02E 60/10 20130101; H01M 2/065 20130101; H01M
2/24 20130101; H01M 2220/20 20130101; H01M 10/0525 20130101; H01M
2/06 20130101; C03C 2207/08 20130101; H01M 2/08 20130101; B23K 1/19
20130101; Y10T 29/49108 20150115; C03C 2204/00 20130101; B23K 26/32
20130101; C03C 8/24 20130101; B23K 2101/36 20180801; B23K 2103/10
20180801; C03C 29/00 20130101; C03C 27/02 20130101; C03C 4/20
20130101; H01M 2300/0037 20130101; C03C 3/19 20130101; B23K 15/0093
20130101 |
Class at
Publication: |
429/163 ;
501/14 |
International
Class: |
C03C 8/00 20060101
C03C008/00; H01M 2/06 20060101 H01M002/06 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 18, 2011 |
DE |
10 2011 011 705.9 |
Feb 25, 2011 |
DE |
10 2011 012 430.6 |
Apr 1, 2011 |
DE |
10 2011 015 869.3 |
Jun 10, 2011 |
DE |
10 2011 103 975.2 |
Jun 10, 2011 |
DE |
10 2011 103 976.0 |
Jul 7, 2011 |
DE |
10 2011 106 873.6 |
Claims
1. A glass, comprising the following components in mole percent
(mol-%): TABLE-US-00006 P.sub.2O.sub.5 35-50 mol-%; Al.sub.2O.sub.3
0-14 mol-%; B.sub.2O.sub.3 2-10 mol-%; Na.sub.2O 0-30 mol-%;
M.sub.2O 0-20 mol-%, wherein M is one of potassium (K), cesium (Cs)
and rubidium (Rb); Li.sub.2O 0-42 mol-%; BaO 0-20 mol-%; and
Bi.sub.2O.sub.3 0-10 mol-%.
2. The glass according to claim 1, the glass having a composition
including: TABLE-US-00007 P.sub.2O.sub.5 39-48 mol-%;
Al.sub.2O.sub.3 2-12 mol-%; B.sub.2O.sub.3 4-8 mol-%; Na.sub.2O
0-20 mol-%; M.sub.2O 12-19 mol-%; Li.sub.2O 0-40 mol-%; BaO 5-20
mol-%; and Bi.sub.2O.sub.3 1-5 mol-%.
3. The glass according to claim 2, the glass composition including:
TABLE-US-00008 Li.sub.2O 17-40 mol-%; and Bi.sub.2O.sub.3 2-5
mol-%.
4. The glass according to claim 1, wherein the glass is a solder
glass.
5. The glass according to claim 1, the glass including at most 35
mol-% Li.sub.2O.
6. The glass according to claim 5, the glass including at most 20
mol-% Li.sub.2O.
7. The glass according to claim 1, the glass including at least 17
mol-% Li.sub.2O.
8. The glass according to claim 1, the glass including 4-8 mol-%
Bi.sub.2O.sub.3.
9. The glass according to claim 1, the glass being lead free except
for contaminants.
10. The glass according to claim 1, the glass including at most 20
mol-% Na.sub.2O.
11. The glass according to claim 1, the glass including at least 1
mol-% Bi.sub.2O.sub.3.
12. The glass according to claim 11, the glass including at least 2
mol-% Bi.sub.2O.sub.3.
13. The glass according to claim 1, the glass having a coefficient
of expansion a at a temperature in a range of between 20.degree. C.
and 300.degree. C. of >14.times.10.sup.-6 per degree Kelvin
(K).
14. The glass according to claim 13, said coefficient of expansion
a at said temperature in said range of between 20.degree. C. and
300.degree. C. of in a range between 15.times.10.sup.-6/K and
25.times.10.sup.-6/K.
15. The glass according to claim 14, said coefficient of expansion
a at said temperature in said range of between 20.degree. C. and
300.degree. C. of in a range between 13.times.10.sup.-6/K and
20.times.10.sup.-6/K.
16. The glass according to claim 1, the glass having a melting
temperature of <600.degree. C.
17. The glass according to claim 1, the glass having a
hemispherical temperature in a range of between 500.degree. C. and
650.degree. C.
18. The glass according to claim 17, said hemispherical temperature
being in a range of between 500.degree. C. and 600.degree. C.
19. The glass according to claim 1, the glass having a composition
such that the glass can be soldered at normal atmosphere with at
least one of aluminum and copper.
20. The glass according to claim 1, the glass having a high
chemical resistance to non-aqueous battery electrolytes.
21. The glass according to claim 20, the glass having a high
chemical resistance to carbonates.
22. The glass according to claim 21, the glass having a high
chemical resistance to carbonate mixtures.
23. The glass according to claim 22, the glass having a chemical
resistance to LiPF.sub.6.
24. A feed-through, comprising: a glass having a composition
including (in mole percent (mol-%)): TABLE-US-00009 P.sub.2O.sub.5
35-50 mol-%; Al.sub.2O.sub.3 0-14 mol-%; B.sub.2O.sub.3 2-10 mol-%;
Na.sub.2O 0-30 mol-%; M.sub.2O 0-20 mol-%, wherein M is one of
potassium (K), cesium (Cs) and rubidium (Rb); Li.sub.2O 0-42 mol-%;
BaO 0-20 mol-%; and Bi.sub.2O.sub.3 0-10 mol-%.
25. The feed-through according to claim 24, the feed-through being
for a device.
26. The feed-through according to claim 25, wherein said device is
a storage device.
27. The feed-through according to claim 26, wherein said storage
device is a lithium-ion battery.
28. The feed-through according to claim 27, wherein said
lithium-ion battery is a lithium-ion accumulator.
29. A device, the device comprising: a feed-through including a
glass having a composition including (in mole percent (mol-%)):
TABLE-US-00010 P.sub.2O.sub.5 35-50 mol-%; Al.sub.2O.sub.3 0-14
mol-%; B.sub.2O.sub.3 2-10 mol-%; Na.sub.2O 0-30 mol-%; M.sub.2O
0-20 mol-%, wherein M is one of potassium (K), cesium (Cs) and
rubidium (Rb); Li.sub.2O 0-42 mol-%; BaO 0-20 mol-%; and
Bi.sub.2O.sub.3 0-10 mol-%.
30. The device according to claim 29, the device being a storage
device.
31. The device according to claim 30, wherein said storage device
is a battery.
32. The device according to claim 31, wherein said storage device
is a lithium-ion battery.
33. The device according to claim 32, wherein said lithium-ion
battery is a lithium-ion accumulator.
34. The device according to claim 33, further comprising a
housing.
35. The device according to claim 34, said housing being a battery
housing.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of PCT application No.
PCT/EP2012/000703, entitled "GLASS, IN PARTICULAR GLASS SOLDER OR
FUSIBLE GLASS", filed Feb. 17, 2012 which is incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a glass and by association
to a glass composition, in particular a solder glass as well as to
a feed-through for a storage device, such as a lithium-ion battery,
for example a lithium-ion accumulator.
[0004] 2. Description of the Related Art
[0005] Solder glasses or fusible glasses are glasses which are used
to bond metals having a high heat expansion and low melting
temperature, for example by means of soldering with a solder glass
or sealing by means of a fusible glass.
[0006] Glasses which find use as solder glasses are known from a
multitude of patent specifications. For example, U.S. Pat. No.
5,262,364 describes a high expansion solder glass comprising 10-25
mol-% Na.sub.2O; 10-25 mol-% K.sub.2O; 5-15 mol-% Al.sub.2O.sub.3;
35-50 mol-% P.sub.2O.sub.5; and 5-15 mol-% PbO and/or BaO. The
solder glass disclosed in U.S. Pat. No. 5,262,364 has a heat
expansion .alpha. in the range of 16.times.10.sup.-6 per degree
Kelvin (K) to 21.times.10.sup.-6/K. A disadvantage of the solder
glass according to U.S. Pat. No. 5,262,364 is that the solder glass
contains lead, in other words PbO as well as a relatively high
amount of Na.sub.2O.
[0007] U.S. Pat. No. 5,965,479 cites a lead-free high expansion
solder glass or fusible glass for use in hermetically sealed
housing for high frequency applications. The lead-free high
expansion solder glass known from U.S. Pat. No. 5,965,479 comprises
10-25 mol-% Na.sub.2O; 10-25 mol-% K.sub.2O; 4-15 mol-%
Al.sub.2O.sub.3; 35-50 mol-% P.sub.2O.sub.5; 5-10 mol-%
B.sub.2O.sub.3; and a content of M.sub.xO which does not exceed 12
mol-%, whereby M.sub.x can be calcium (Ca) or magnesium (Mg). Even
though these glasses contain little or no lead, they do have very
high alkali content.
[0008] Phosphate glasses for joining of metal and glass or glass
ceramic are described in U.S. Pat. No. 4,455,384. Such phosphate
glasses are generally chemically resistant and vacuum tight.
Phosphate glasses in other applications, for example optical
applications have been described many times, for example in DE
15996854, JP 90188442, as well as JP91218941 A.
[0009] Feed-throughs featuring high thermal expansion materials
such as aluminum, aluminum alloys, copper and copper alloys and
glass materials have become known only in the area of high
frequency feed-throughs (HF feed-through). Such HF feed-throughs
with glass materials on the basis of aluminum-phosphate glasses are
known for example from U.S. Pat. No. 5,262,364 and U.S. Pat. No.
5,965,469 as well as U.S. Pat. No. 6,037,539.
[0010] In particular U.S. Pat. No. 6,037,539 describes an HF
feed-through wherein a non-ferrous conductor in an
aluminum-phosphate glass composition is guided through a housing
component comprising aluminum. The HF feed-through known from U.S.
Pat. No. 6,037,539 is substantially optimized for its purpose of
application. Frequencies of between 8 and 1000 megahertz (MHz) are
preferably transferred with feed-throughs of this type. The high
voltage application is also described in U.S. Pat. No. 6,037,539.
However, the battery feed-throughs are not described in U.S. Pat.
No. 6,037,539.
[0011] Lithium-ion accumulators are intended for various
applications, for example for portable electronic equipment, cell
phones, power tools and in particular electric vehicles. The
batteries can replace traditional energy sources, for example
lead-acid batteries, nickel-cadmium batteries or nickel-metal
hydride batteries. Lithium-ion batteries have been known for many
years. In this regard we refer you to the "Handbook of Batteries,
published by David Linden, 2nd issue, McGrawhill, 1995, chapters 36
and 39".
[0012] Various aspects of lithium-ion accumulators are described in
a multitude of patents, for example: U.S. Pat. No. 961,672; U.S.
Pat. No. 5,952,126; U.S. Pat. No. 5,900,183; U.S. Pat. No.
5,874,185; U.S. Pat. No. 5,849,434; U.S. Pat. No. 5,853,914; and
U.S. Pat. No. 5,773,959.
[0013] In particular in the use of storage devices, such as
lithium-ion accumulators in the automobile industry, a multitude of
problems such as corrosion resistance, stability in accidents and
vibration resistance must be solved. An additional problem is the
hermetic seal of the battery, for example the lithium-ion battery
over an extended period of time. The hermetic seal may, for
example, be compromised by leakage in the area of the electrodes of
the battery or respectively the electrode feed-through of the
battery. The seal may for example be compromised by a battery short
circuit or temperature changes resulting in a shortened life span.
An additional problem with battery feed-throughs is the instability
against aggressive battery electrolytes, in particular non-aqueous
electrolytes as are used, for example in lithium-ion
accumulators.
[0014] In order to ensure better stability in accidents, a housing
for a lithium-ion battery is suggested, for example in DE 101 05
877 A1, whereby the housing includes a metal jacket which is open
on both sides and which is being sealed. The power connection is
insulated by a synthetic material. A disadvantage of the synthetic
material insulation is the limited temperature resistance, the
uncertain hermetic seal over the service life and the limited
chemical stability in regard to the battery electrolytes.
[0015] What is needed in the art is a glass, in particular a solder
glass or fusible glass, which avoids the problems of the current
state of the art.
SUMMARY OF THE INVENTION
[0016] The present invention provides a glass which can be used as
a joining glass or fusible glass for a feed-through, for example
for a hermetic feed-through, in particular for a storage device
with an electrolyte, for example an aggressive electrolyte as used
in lithium-ion batteries.
[0017] A battery according to the present invention is to be
understood to be a disposable battery which is disposed of and/or
recycled after its discharge, as well as an accumulator.
[0018] As materials for the housing and feed-throughs for
lithium-ion accumulators light metal, in particular aluminum,
AlSiC, aluminum alloys, magnesium, magnesium alloys, titanium or
titanium alloys are feasible.
[0019] The inventive glass, in particular solder glass or fusible
glass, includes the following components in mole percent
(mol-%):
TABLE-US-00001 P.sub.2O.sub.5 35-50 mol-%, for example 39-48 mol-%;
Al.sub.2O.sub.3 0-14 mol-%, for example 2-12 mol-%; B.sub.2O.sub.3
2-10 mol-%, for example 4-8 mol-%; Na.sub.2O 0-30 mol-%, for
example 0-20 mol-%; M.sub.2O 0-20 mol-%, for example 12-19 mol-%;
whereby M is, for example, potassium (K), cesium (Cs) or rubidium
(Rb); Li.sub.2O 0-45 mol-%, for example 0-40 mol-%, or 17-40 mol-%;
BaO 0-20 mol-%, or 5-20 mol-%; and Bi.sub.2O.sub.3 0-10 mol-%, for
example 1-5 mol-%, or 2-5 mol-%.
[0020] Additional components are optional and are also included in
the present invention. With the exception of contaminants, the
glass composition according to the present invention may be
lead-free, that is PbO can be 0 mol-% in the glass composition.
Lead-free in the current invention means that less than
approximately 100 parts per million (ppm), for example less than 10
ppm, or less than 1 ppm lead contaminants are contained
therein.
[0021] The listed glass compositions are generally stable phosphate
glasses which have a clearly lower overall alkali content than
alkali-phosphate glasses known from the current state of the
art.
[0022] Surprisingly it has been shown that the inventive glass
composition with a lithium-share of up to 45 mol-%, for example 35
mol-% are crystallization-stable, meaning they do not display
detrimental crystallization during a subsequent sintering process.
At a lithium-content of up to 35 mol-%, significant crystallization
is no longer produced. The high crystallization stability of the
phosphate glasses ensures that melting of the glasses generally is
not hindered even at temperatures of <600.degree. C. This allows
the inventive glass composition to be used as solder glass, since
melting of the glasses generally is not hindered even at
temperatures of <600.degree. C.
[0023] The inventive glass has a heat expansion .alpha. in the
range of 20.degree. C. to 300.degree. C.>14.times.10.sup.-6/K
and a low soldering temperature or respectively sealing
temperature. The soldering temperature or sealing temperature of
the glass is surprisingly lower than the melting temperature of the
metals aluminum (660.degree. C.), copper (1084.degree. C.), and
high-grade steel (>1400.degree. C.). The thermal expansion
.alpha. (20.degree. C. to 300.degree. C.) is in the range of a
(20.degree. C. to 300.degree. C.) of conventional metals such as
aluminum (Al) (.alpha..apprxeq.23.times.10.sup.-6/K) copper (Cu);
(.alpha..apprxeq.16.5.times.10.sup.-6/K); and high grade steel
(.alpha..apprxeq.17.times.10.sup.-6/K). The inventive glasses
moreover have a high resistance in regard to non-aqueous
electrolytes, for example LiPF.sub.6, for example 1 Molar (M)
LiPF.sub.6 in ethylene carbonate/dimethyl carbonate 1:1, as well as
high hydrolytic resistance to Hydrofluoric acid (HF). The inventive
glasses are therefore especially suitable for the production of
hermetic feed-throughs for housings for storage cells or storage
devices, in particular lithium-ion storage devices.
[0024] One advantage of the inventive glass compositions is that
lithium is integrated into the glass structure. Since lithium is
contained in the electrolyte in the form that the electrolyte is
used in lithium-ion storage devices, the battery efficiency should
not be impaired. The glass composition moreover has a high heat
expansion .alpha. in the range of 20.degree. C. to 300.degree. C.
and a solder temperature below the melting point of the metals
which are to be soldered or sealed, as described above.
[0025] Since the diffusion of the alkali-ions occurs in
Na+>K+>Cs+sequence, low sodium or respectively sodium-free
glasses are especially resistant to electrolytes, especially those
which are used in lithium-ion storage devices.
[0026] In a first embodiment of the present invention, the glass
composition includes at least 17 mol-% and at most 35 mol-%
Li.sub.2O. Such glass compositions are sufficiently resistant in
regard to electrodes which contain lithium and also sufficiently
crystallization-stable, whereby melting of the glasses is generally
not hampered even at temperatures of <600.degree. C.
[0027] An additional glass composition according to the present
invention includes 4-8 mol-% B.sub.2O.sub.3. Bi.sub.2O.sub.3 in
particular can replace the environmentally damaging PbO. Moreover,
the addition of Bi.sub.2O.sub.3 can also clearly increase the water
resistance. For example, with only a small addition of 1 mol-%
Bi.sub.2O.sub.3 an alkali-phosphate glass composition having
essentially the same alkali content can be made 10-times more water
resistant than an alkali-phosphate composition in which there is no
Bi.sub.2O.sub.3 except for contaminants. This effect was surprising
for an expert.
[0028] Especially preferred for environmental reasons are glasses
which--except for contaminants are free of Pb. In this application
"free of Pb, except for contaminants" as previously explained means
that the glass includes <100 ppm, for example <10 ppm, or
<1 ppm lead.
[0029] The glass composition, for example, has a coefficient of
expansion .alpha. (20.degree. C. to 300.degree. C.) in the range of
>14.times.10.sup.-6/K, for example 15-10.sup.-6/K to
25.times.10.sup.-6/K, or 13.times.10.sup.-6/K to
20.times.10.sup.-6/K. Glass compositions with this type of
coefficient of expansion or .alpha. (20.degree. C. to 300.degree.
C.) are adapted to the coefficients of expansion of conventional
metals such as aluminum (Al)
(.alpha..apprxeq.23.times.10.sup.-6/K), Cu
(.alpha..apprxeq.16.5.times.10.sup.-6/K), and high grade steel
(.alpha..apprxeq.17.times.10.sup.-6/K). If the glass is to be
sealed with light metals like aluminum the glass composition has
for example a melting temperature <600.degree. C.
[0030] In one embodiment of the present invention, the glass
composition has a hemispherical temperature in the range of
500.degree. C. to 650.degree. C., for example in the range of
500.degree. C. to 600.degree. C.
[0031] Sealing temperature of the glass or glass ceramic is to be
understood to be the temperature of the glass or the glass ceramic
whereby the glass material softens and then fits so closely against
the metal with which is to be sealed that a bonded joint connection
is obtained between the glass or the glass ceramic and the
metal.
[0032] The sealing temperature may, for example, be determined
through the hemispherical temperature as described in R. Gorke, K.
J. Leers: Keram. Z. 48 (1996) 300-305, or according to DIN 51730,
ISO 540 or CEN/TS 15404 and 15370-1 whose disclosure content is
incorporated in its entirety into the current patent application.
The measurement of the hemispherical temperature is described in
detail in DE 10 2009 011 182 A1 whose disclosure content is
incorporated in its entirety into the current patent application.
According to DE 10 2009 011 182A1 the hemispherical temperature can
be determined in a microscopic process by using a heating stage
microscope. It identifies the temperature at which an originally
cylindrical test body melts into a hemispherical mass. A viscosity
of approximately log .eta..sub.1=4.6 deciPascals (dPas) can be
allocated to the hemispherical temperature, as can be learned from
appropriate technical literature. If a crystallization-free glass,
for example in the form of a glass powder, is melted and then
cooled so that it solidifies, it can then normally be melted down
again at the same melting temperature. For a bonded connection with
a crystallization-free glass this means that the operating
temperature to which the bonded connection is continuously
subjected may not be higher than the sealing temperature. Glass
compositions as utilized in the current application are generally
often produced from a glass powder which is melted down and which,
under the influence of heat provides the bonded connection with the
components which are to be joined. Generally, the sealing
temperature or melting temperature is consistent with the level of
the so-called hemispherical temperature of the glass. Glasses
having low sealing temperatures or respectively melting
temperatures are also referred to as solder glass. Instead of
sealing or melting temperature, one speaks of solder temperature or
soldering temperature in this instance. The sealing temperature or
respectively the solder temperature may deviate from the
hemispherical temperature by +20K.
[0033] According to the present invention, the glass has such a
composition that the glass can be soldered or sealed under normal
atmosphere with aluminum (Al) and/or copper (Cu). Then, all Al--Al
or Al--Cu compositions can be soldered or sealed with the cited
glasses. The inventive glasses are especially suited for contact
with aggressive fluoric media. These types of fluoric media find
application, for example, as electrolytes in lithium-ion
batteries.
[0034] In accordance with one embodiment of the present invention,
the glass or respectively the glass composition has a very high
chemical resistance in regard to non-aqueous battery electrolytes,
in particular in regard to carbonates, such as carbonate mixtures,
for example including LiPF.sub.6.
[0035] In addition to the glass or respectively the glass
composition, the present invention also cites a feed-through, for
example for a storage device, such as a lithium-ion battery, for
example a lithium-ion accumulator having an inventive glass
composition.
[0036] Moreover, a lithium-ion battery with such a feed-through is
provided. Even though the current description is for battery
feed-throughs, the present invention is not restricted thereto. The
glass compositions can be used for feed-throughs of any type, in
particular however for those whose base body and/or housing and
optionally also the conductor consist of a light metal, such as
aluminum. Conceivable feed-throughs are feed-throughs for example
for components, in particular electronic components which are used
in light construction, for example in aircraft construction in the
aerospace industry and which, in particular must have sufficient
temperature stability. Electronic components may for example be
sensors and/or actuators.
[0037] A feed-through, for example for a battery feed-through, in
particular for a lithium-ion battery, or for a lithium-ion
accumulator has a base body, whereby the base body has at least one
opening through which a conductor, for example a substantially
pin-shaped conductor embedded in a glass material formed of the
inventive composition is guided. The base body contains a material
which has a low melting point, for example a light metal, such as
aluminum or AlSiC, magnesium or titanium. Alloys, such as light
metal alloys, for example aluminum alloys, magnesium alloys or
titanium alloys, for example Ti6246 or Ti6242 are also conceivable.
Titanium is a material which is well tolerated by the body, so that
it is used for medical applications, for example in prosthetics.
Due to its strength, resistance and low weight its use is also
favored in special applications, for example in racing sports, but
also in aviation and aerospace applications.
[0038] Additional materials feasible for the base body and/or the
battery housing are metals, especially steel, stainless steel,
high-grade steel or tool steel which is intended for a later heat
treatment. Suitable for use as high-grade steels are for example
X12CrMoS17, X5CrNi1810, XCrNiS189, X2CrNi1911, X12CrNi177,
X5CrNiMo17-12-2, X6CrNiMoTi17-12-2, X6CrNiTi1810 and
X15CrNiSi25-20, X10CrNi1808, X2CrNiMo17-12-2, X6CrNiMoTi17-12-2. In
order to be able to provide an especially effective weldability
during laser welding as well as during resistance welding,
high-grade steels, in particular Cr--Ni-steels (chromium-nickel
steels) having material grade numbers according to Euro-Norm (EN)
1.4301, 1.4302, 1.4303, 1.4304, 1.4305, 1.4306, 1.4307 are used as
materials for the base body and/or the housing component, in
particular the battery cell housing. St35, St37 or St38 can be used
as standard steel.
[0039] In order to avoid that during the sealing process the light
metal of the base body and possibly also of the metal pin melts or
deforms, the sealing temperature of the glass material with the
material of the base body and/or the conductor is below the melting
temperature of the material of the base body or respectively the
conductor. The sealing temperature of the cited glass compositions
is below 650.degree. C., for example in the range of 350.degree. C.
to 650.degree. C. The sealing temperature may for example be
determined through the hemispherical temperature as described in R.
Gorke, K. J. Leers: Keram. Z.48 (1996) 300-305, or according to DIN
51730, ISO 540 or CEN/TS 15404 and 15370-1 whose disclosure content
is incorporated in its entirety into the current patent
application.
[0040] Sealing the conductor into the opening can then be
accomplished as follows: First, the glass material of the inventive
composition is inserted into the opening in the base body, together
with the pin shaped conductor. Then, the glass together with the
conductor, in particular the pin shaped conductor, is heated to the
sealing temperature or respectively the hemispherical temperature
of the glass, so that the glass material softens and envelops the
conductor, in particular the pin shaped conductor in the opening
and fits closely against the base body. Since the melting
temperature of the material of the base body as well as of the
conductor, in particular the pin shaped conductor, is higher than
the sealing temperature of the glass material, the base body, as
well as the pin shaped conductor are in a solid state. The sealing
temperature of the glass material is, for example, between 20 to
150 K below the melting temperature of the material of the base
body, or respectively of the pin shaped conductor. If for example,
the light metal used is aluminum having a melting point of
T.sub.MELT=660.32.degree. C., then the fusing temperature or
respectively solder temperature of the glass material is in the
range of 350.degree. C. to 640.degree. C., for example in the range
of 350.degree. C. to 550.degree. C., or in the range of 450.degree.
C. to 550.degree. C. As an alternative to a light metal such as
aluminum, an aluminum alloy, magnesium, a magnesium alloy,
titanium, a titanium alloy and an SiC matrix which is infiltrated
with aluminum could also be used as material for the base body. A
material of this type is also described as AlSiC. AlSiC has a SiC
core into which aluminum is infused. Based on the proportion of
aluminum the properties, especially the coefficient of expansion
can be adjusted. AlSiC notably has a lower heat expansion than pure
aluminum.
[0041] In the current application metals which have a specific
weight of less than 5.0 kilograms per cubic decimeter (kg/dm.sup.3)
are understood to be light metals. The specific weight of the light
metals is, for example in the range of 1.0 kg/dm.sup.3 to 3.0
kg/dm.sup.3.
[0042] If the light metals are additionally used as materials for
the conductors, for example for the pin-shaped conductor or the
electrode connecting component, then the light metals further
distinguish themselves through a specific electric conductivity in
the range of 5.times.10.sup.6 Siemens per meter (S/m) to
50.times.10.sup.6 S/m.
[0043] Other feasible materials would be steel, stainless steel or
high-grade steel.
[0044] The material of the conductor, in particular the pin shaped
conductor can be identical to the material of the base body, for
example aluminum or AlSiC. This has the advantage that the
coefficient of expansion of the base body and the metal pin is
identical. The coefficient of expansion .alpha. of the glass- or
glass ceramic material needs then only to be adapted to one
material. Furthermore, the outer conductor may include high-grade
steel or steel.
[0045] Alternatively the conductor, in particular the pin shaped
conductor may include copper (Cu), CuSiC or a copper alloy,
magnesium or magnesium alloys, gold or gold alloys, silver or
silver alloys, NiFe, a NiFe jacket with an interior copper part, as
well as a cobalt iron alloy as materials.
[0046] As aluminum or respectively an aluminum alloy for the
conductor, the following are exemplary materials:
TABLE-US-00002 EN AW-1050 A; EN AW-1350; EN AW-2014; EN AW-3003; EN
AW-4032; EN AW-5019; EN AW-5056; EN AW-5083; EN AW-5556A; EN
AW-6060; and EN AW-6061.
[0047] As copper or respectively copper alloys for the conductor,
use of the following are exemplary materials:
TABLE-US-00003 Cu-PHC 2.0070; Cu-OF 2.0070; Cu-ETP 2.0065; Cu-HCP
2.0070; and Cu-DHP 2.0090.
[0048] In the case that the base body and the metal pin are formed
of different materials, .alpha..sub.base
body.gtoreq..alpha..sub.glass.gtoreq..alpha..sub.metal pin, for
example applies.
[0049] If the thermal expansions of the components deviate from
each other as previously described, then the result is compression
seal feed-throughs or respectively compression seals in the form of
special seals, whereby different thermal expansions of glass or
glass ceramic material and surrounding metal lead to a frictional
connection of glass or glass ceramic material and surrounding
metal. These types of compression seal feed-throughs are used for
example for airbag igniters. In the case of compression seal
feed-throughs the glass or glass ceramic material adheres to the
surrounding metal; however no molecular connection exists between
the glass or glass ceramic material and the metal. The frictional
connection is lost as soon as the opposing force of the static
friction is exceeded. A chemical joining of glass or glass ceramic
material can be achieved if the surfaces are treated or if the
glass material is joined with the surrounding metal through a
welding connection, for example an ultrasonic welding
connection.
[0050] Feed-throughs, in particular battery feed-throughs with the
inventive glass composition distinguish themselves in that sealing
is possible in a base body consisting of a low melting material and
that sufficient resistance is provided in regard to a battery
electrolyte. The seal may be a compression seal as well as an
adapted seal. In the case of an adapted seal, the coefficients of
expansion .alpha. (20.degree. C.-300.degree. C.) of glass and
surrounding materials or respectively materials to be sealed are
essentially the same.
[0051] In particular, the glasses have sufficient chemical
stability in regard to generally aggressive battery electrolytes.
Non-aqueous battery electrolytes consist typically of a carbonate,
in particular a carbonate mixture, for example a mixture of
ethylene-carbonate and dimethyl-carbonate, whereby the aggressive
non-aqueous battery electrolytes have a conducting salt, for
example LiPF.sub.6, for example in the form of a 1 Molar (M)
solution.
[0052] The resistance of the composition according to the present
invention against the battery electrolytes can be verified in that
the glass composition in the form of a glass powder is ground to a
granularity of d50=10 micrometers (.mu.m) and is stored in the
electrolytes for a predetermined time period, for example one week.
d50 means that 50% of all particles or granules of the glass powder
are smaller than or equivalent to a diameter of 10 .mu.m. As a
non-aqueous electrolyte, a carbonate mixture of ethylene-carbonate
and dimethyl-carbonate is used for example at a ratio of 1:1 with a
Molar LiPF.sub.6 as conducting salt. After the glass powder was
exposed to the electrolyte, the glass powder can be filtered off
and the electrolyte be examined for glass elements which were
leached from the glass. Herein it was demonstrated that with the
glasses used according to the present invention such leaching in
the utilized composition ranges occurs surprisingly only to a
limited extent of less than 20 mass percent; and that in special
instances leaching of <5 mass percent is achieved at a thermal
expansion .alpha. in a temperature range of (20.degree. C. to
300.degree. C.) in a range between 15.times.10.sup.-6/K and
25.times.10.sup.-6/K. An additional advantage of the glass
composition according to the present invention which finds use in a
battery feed-through with one or several pins can be seen in that
sealing of the glass with the surrounding light metal or
respectively the metal of the conductor, in particular in the
embodiment of a metal pin is possible also in a gaseous atmosphere
which is not an inert gas atmosphere. In contrast to the previously
used method, a vacuum is also no longer necessary for
aluminum-sealing. This type of sealing can rather occur under
atmospheric conditions. For both types of sealing nitrogen
(N.sub.2) or argon (Ar) can be used as inert gas. As a
pre-treatment for sealing, the metal is cleaned and/or etched, and
if necessary is subjected to targeted oxidizing or coating. During
the process temperatures of between 300 and 600.degree. C. are used
at heating rates of 0.1 to 30 degrees Kelvin per minute (K/min) and
dwell times of 1 to 60 minutes.
[0053] The inventive glass compositions surprisingly show a high
chemical stability relative to the non-aqueous electrolyte and at
the same time a high thermal coefficient of expansion. This is
surprising especially because it is assumed that the glass becomes
increasingly unstable the higher the thermal coefficient. It is
therefore surprising that in spite of the high coefficient of
expansion and the low sealing temperature the inventive glass
compositions offer a sufficient stability.
[0054] The listed inventive glass composition can be provided with
fillers for the purpose of expansion adaptation that is, for
adaptation of the coefficient of expansion.
[0055] In order to make the glass composition accessible for
infrared-heating or IR-heating, the aforementioned glasses can be
provided with doping agents having an emission maximum in the range
of infrared radiation, in particular IR-radiation of an IR-source.
Examples of materials for this are iron (Fe), chromium (Cr),
manganese (Mn), cobalt (Co), vanadium (V), and pigments. The thus
prepared glass material can be heated by locally targeted infrared
radiation.
[0056] The feed-through, in particular a battery feed-through with
the inventive glasses in contrast to feed-throughs from the current
state of the art, in particular those using plastic as sealing
material, moreover distinguishes itself through a high temperature
resistance, in particular temperature change resistance. Moreover,
a hermetic seal is also provided during temperature change, thus
avoiding that battery liquid can emerge from and/or moisture can
penetrate into the housing. It is understood that with a hermetic
seal the helium leakage rate is <1.times.10.sup.-8
millibarLiters per second (mbarL/s), for example
<1.times.10.sup.-9 mbarL/s at a pressure differential of 1
bar.
[0057] The feed-through according to the present invention, in
particular the battery feed-through, has a sufficient chemical
stability, in particular in regard to non-aqueous battery
electrolytes.
[0058] The feed-throughs can be used with the inventive glass
compositions or glasses in electrical devices, in particular in
storage devices, in particular a battery, preferably a battery
cell. The housing of the battery cell consists, for example of the
same material as the base body of the feed-through, such as a light
metal. In the case of battery cells, the base body is, for example
part of the battery housing. The battery is, for example, a
lithium-ion battery.
[0059] The battery may have a non-aqueous electrolyte, for example
on a carbonate basis, such as a carbonate mixture. The carbonate
mixture can include ethylene-carbonate mixed with
dimethyl-carbonate with a conducting salt, for example
LiPF.sub.6.
BRIEF DESCRIPTION OF THE DRAWINGS
[0060] 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 an embodiment of the invention
taken in conjunction with the accompanying drawing, wherein:
[0061] FIG. 1 illustrates an inventive feed-through.
[0062] The exemplification set out herein illustrates one
embodiment of the invention and such exemplification is not to be
construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
[0063] Referring now to the drawing, and more particularly to FIG.
1, there is shown a feed-through 1 according to the present
invention. Feed-through 1 includes a metal pin 3 as a conductor, in
particular as a pin shaped conductor which consists for example of
a material, such as aluminum or copper. It further includes a base
body 5 in the embodiment of a metal part consisting according to
the present invention of a metal which has a low melting point,
that is a light metal such as aluminum. Metal pin 3 is guided
through an opening 7 which leads through metal part 5. Even though
only the insertion of a single metal pin through the opening is
illustrated, several metal pins could be inserted through the
opening, without deviating from the present invention.
[0064] The outer contour of opening 7 can be round, but also oval.
Opening 7 penetrates through the entire thickness D of base body 5,
or respectively metal part 5. Metal pin 3 is sealed into a glass
material 10 and is inserted inside glass material 10 through
opening 7 through base body 5. Opening 7 is introduced into base
body 5 through a separation process, for example stamping. In order
to provide a hermetic feed-through of metal pin 3 through opening
7, metal pin 3 is sealed into a glass plug consisting of the
inventive glass material. A substantial advantage of this
production method consists in that even under increased pressure
upon the glass plug, for example a compression load, expulsion of
the glass plug with metal pin from opening 7 is avoided. The
sealing temperature of inventive glass material 10 with the base
body 5 is 20K to 100K below the melting temperature of the material
of base body 5 and/or of the conductor 3, for example the pin
shaped conductor 3.
TABLE-US-00004 TABLE 1 Examples (AB1-AB8): Mol-% AB1 AB2 AB3 AB4
AB5 AB6 AB7 AB8 P.sub.2O.sub.5 47.6 43.3 43.3 43.3 37.1 40.0 42.0
46.5 Al.sub.2O.sub.3 4.2 8.6 8.7 2.0 2 12.0 12.0 4.2 B.sub.2O.sub.3
7.6 4.8 4.7 4.8 4.9 6.0 6.0 7.6 Na.sub.2O 28.3 17.3 15.0 16.0 28.3
K.sub.2O 12.4 17.3 17.3 18.0 19.0 12.4 PbO 9.0 0 0 BaO 8.7 8.7 15.4
14 Li.sub.2O 17.3 34.6 42.1 Bi.sub.2O.sub.3 5 1 Hemispherical 513
554 564 540 625 553 502 Temperature (.degree. C.) .alpha.
(20-300.degree. C.) 19 17.2 15.1 13.7 14.8 16.7 16.0 19.8
(10.sup.-6/K) Tg (.degree. C.) 325 375 354 369 359 392 425 347
Density [g/cm.sup.3] 2.56 3 3 Leaching in Mass % 18.7 3.7 3.7
Weight Loss (%) 10.7 0.37 0.1 0.13 0.13 n.b. 0.006/0.001 0.45/0.66
after 70 hours in 70.degree. C.-water
[0065] Besides leaching, the hydrolytic resistances of the
individual glasses were also determined.
[0066] The hydrolytic resistance tests were conducted so that
melted down glass samples were produced (2.times.2 centimeters
(cm), height: .about.0.5 cm) which were stored in 200 milliliters
(ml) water at 25.degree. C. and 70.degree. C. for 70 hours.
Subsequently the material loss in weight-% was determined and
listed in the table.
[0067] Example 1 (AB1) in Table 1 is suitable, for example, for
aluminum/aluminum sealing, that is sealing an aluminum pin as
conductor into a surrounding aluminum base body.
[0068] Even though some of the examples indicate a coefficient of
expansion which is too low for bonding with copper (Cu) it becomes
clear that a high lithium component can be dissolved in the molten
mass without the glass becoming unstable with a glass composition
of this type.
[0069] Examples AB7 and AB8 distinguish themselves in that they
contain Bi.sub.2O.sub.3, in place of PbO, as is the case in example
6 (AB6).
[0070] Surprisingly it has been shown that the hydrolytic
resistance can be clearly increased by including Bi.sub.2O.sub.3.
For example, by introducing 1 mol-% Bi.sub.2O.sub.3, a 10-times
higher hydrolytic resistance can be achieved compared to example
AB1. Bi.sub.2O.sub.3, can in particular also be used in place of
PbO according to example 6. Exemplary glass compositions according
to the present invention which distinguish themselves as being
environmentally friendly are lead free, in other words free of PbO,
except for contaminants. These are for example examples AB1, AB2,
AB3, AB4, ABS, AB7 and AB8.
[0071] An especially crystallization stable glass composition which
displays no, or almost no substantial crystallization is achieved
when the lithium content is less than 35 mol-%, for example less
than 20 mol-%. These are for example examples AB1, AB2, AB3, AB4,
AB6, AB7 and AB8.
[0072] A special resistance in regard to electrolytes is achieved
if the sodium content is less than 20 mol-%. This is especially
true of sodium free glasses, in other words glasses which are free
of sodium except for contaminants. These are for example the
examples AB2, AB3, AB4, AB5, AB6 and AB7.
[0073] An especially high hydrolytic water resistance is achieved,
if at least 1 mol-% Bi.sub.2O.sub.3, for example at least 2 mol-%
Bi.sub.2O.sub.3 is present in the glass composition. This is the
case for example in examples AB7 and AB8.
[0074] Table 2 below lists conventional glass compositions
(VB1-VB9) which were examined in comparison to the aforementioned
inventive examples AB1-AB8.
[0075] Tables 1 and 2 show the composition in mol-%, the
transformation temperature Tg as defined for example in "Schott
Guide to Glass, second edition, 1996, Chapman & Hall, pages
18-21, the total leaching in mass percentage (Ma-%), the
coefficient of expansion .alpha. in 10.sup.-6/K in the range of
20.degree. C.-300.degree. C., as well as the density in grams per
cubic centimeter (g/cm.sup.3). The total leaching is determined as
described in the introductory section, meaning that the glass
compositions were ground to glass powder having a d50=10
micrometers (.mu.m) granularity, and were exposed for one week to
the electrolyte consisting of ethylene-carbonate/dimethyl-carbonate
at a ratio 1:1, with 1 Molar LiPF.sub.6 in the form of conducting
salt dissolved therein and after this time were examined for glass
components which were leached from the glass. "n.b." in Table 1
denotes unknown properties.
TABLE-US-00005 TABLE 2 Comparison examples VB 1 VB 2 VB 3 VB 4 VB 5
VB 6 VB 7 VB 8 VB 9 System SiO.sub.2 SiO.sub.2 SiO.sub.2 SiO.sub.2
P.sub.2O.sub.5 P.sub.2O.sub.5 P.sub.2O.sub.5 P.sub.2O.sub.5
P.sub.2O.sub.5 Composition [mol-%] SiO.sub.2 66.5 66.6 63.3 77.8
55.4 2.6 ZrO.sub.2 2.4 11.8 Al.sub.2O.sub.3 9.3 10.4 1.0 3.3 8.4
5.5 12.8 4.0 7.4 B.sub.2O.sub.3 4.0 7.3 4.1 9.4 31.2 1.7 MgO 4.0
4.4 3.3 4.3 20.5 2.9 BaO 3.8 1.5 2.5 0.2 7.0 7.8 La.sub.2O.sub.3
1.3 Li.sub.2O 0.6 K.sub.2O 7.9 2.0 2.4 P.sub.2O.sub.5 5.3 6.8 29.3
59.7 50.5 CaO 12.3 9.6 4.7 1.6 7.9 8.1 Na.sub.2O 9.1 7.0 0.5 SrO
11.3 F 1.0 0.6 54.7 PbO SnO 27.0 42.2 ZnO 8.9 Tg 720 716 508 562
464 680 n.b. 462 n.b. Total leaching in Mass % 43.5 52.4 167.0 64.4
2.1 127.6 50.2 18.8 1.9 .alpha. (20.degree. C.-300.degree. C.) 4.6
3.8 10.4 4.9 14.8 5.5 n.b. n.b. n.b. Density [g/cm.sup.3] 2.6 2.5
n.b. 2.3 3.7 2.8 n.b. 2.8 n.b.
[0076] The comparison examples VB1, VB2 and VB6 cited in table 2
show a transformation temperature Tg which is too high and a
thermal coefficient of expansion .alpha. which is too low compared
to the inventive compositions (AB1-AB8) in table 1. Comparison
example VB3 does have a sufficiently low Tg, a better, however not
sufficient coefficient of expansion .alpha. (20.degree. C. to
300.degree. C.), however a high instability in respect to
electrolytes. Comparison example VB4 shows a favorable Tg, however
the resistance and the coefficient of expansion a are not
sufficient. Comparison example shows VB5 an excellent resistance,
the Tg is satisfactory, however the coefficient of expansion a is
not sufficient.
[0077] Surprisingly, inventive examples AB1 to AB8 of the inventive
glass compositions according to table 1 show a high a, (20.degree.
C.-300.degree. C.) according to the present invention, low Tg and
high chemical resistance. The inventive glass compositions thereby
provide sealing glasses for use in battery feed-throughs, having a
low process temperature, a sealing temperature which is lower than
the melting point of aluminum, a high coefficient of expansion a
and an excellent resistance to battery electrolytes. Even though
the glass compositions are described for use in feed-throughs, in
particular battery feed-throughs they are not restricted thereto.
Other fields of application are, for example, sealing of housings,
of sensors and/or actuators. In principle the feed-throughs are
suitable for all applications in lightweight construction, in
particular as feed-throughs in electrical components which must be
light and temperature resistant. Such components are found for
example in aircraft construction and in astronautics.
[0078] 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.
* * * * *