Patent Grant
9012079
This applications claims priority from United Kingdom Application Serial No. 0713896.9, filed Jul. 17, 2007, the entire content of which is hereby incorporated by reference, and is a U.S. national stage application under 35 U.S.C. §371 of PCT/GB08/02453, filed Jul. 17, 2008, the entire content of which is hereby incorporated by reference.
The invention relates to a method of fabricating a composite electrode comprising an active component directly bonded to a current collector and its use as the active anode material in rechargeable lithium battery cells.
Lithium battery cells, as illustrated in
A number of investigations have been carried out using silicon as the active anode material of a rechargeable lithium-ion electrochemical cell (see, for example, Insertion Electrode Materials for Rechargeable Lithium Batteries, M. Winter, J. O. Besenhard, M. E. Spahr, and P. Novak in Adv. Mater. 1998, 10, No. 10). The silicon anode would replace the graphite-based anode electrode in the conventional lithium-ion rechargeable battery cell illustrated in
It will be appreciated that the formation of a conventional composite electrode requires multiple components hence increasing the cost and complexity of the production of the electrode. Furthermore, the use of a solvent casting process results in the formation of waste solvent, which requires costly disposal. It will be further appreciated that, in order to allow the battery to deliver high levels of power, it is very important to create a low resistance contact between the active material and the current collector and this can be hard to achieve in a composite film electrode structure. In addition, the low resistance contacts will be preserved during the volume changes induced by charging and discharging the electrode in an electrochemical cell.
The present invention provides an improved method of composite electrode production. In particular, the first aspect of the invention provides a composite electrode comprising an active component directly bonded to a current collector. The direct bonding provides a low resistance contact between the current collector and the active material.
It will be appreciated that the electrode of the first aspect does not require the use of a polymer binder and an electronic additive. Instead the active component is directly bonded to the current collector by the formation of a compound between the active component and the current collector. Furthermore, the production of the composite electrode is not carried out using a solvent casting process thus avoiding the use of solvent and the need to dispose of waste solvent.
For the purposes of the present invention, the active component and the current collector are directly bonded such that a physical and/or chemical interaction occurs between the active component and the current collector. In particular, the physical and/or chemical interaction occurs at the interface between the active component and the current collector (i.e. at the contacting surfaces of the active component and the current collector). The direct bonding of the active component and the current collector results in a permanent or temporary attachment. The bonding can therefore be irreversible or reversible. The bonding can result in an interaction at an atomic or molecular level between the active component and the current collector. In particular, the interaction may result in chemical bonding between the active component and the current collector such as covalent, ionic, van der Waals bonding or the formation of an alloy, such as a metal alloy. The direct bonding causes the active component and the current collector to adhere to each other. It will be appreciated that the direct bonding causes a physical and/or chemical change in the contacting surfaces of the active component and/or the current collector.
The direct bonding of the active component and the current collector can result in the formation of a compound between the active component and the current collector. In this case, the direct bonding of the active component and the current collector is via the compound formed between the active component and the current collector. The compound therefore has two functions. It causes the adherence of the active component to the current collector and allows electrons to be conducted therethrough. The compound therefore provides a high conductivity and low resistance binding between the current collector and the active component.
The active component of the electrode preferably comprises one or more of silicon, aluminium, tin, lead, bismuth, antimony or silver. The current collector of the electrode preferably comprises one or more of copper, nickel, aluminium, iron, iridium, gold, silver or titanium. The electrode of the first aspect can therefore comprise for example, an active component comprising silicon directly bonded via a silicon-copper compound to a copper current collector.
In a preferred feature of the invention, the active component comprises silicon, more preferably silicon-comprising fibres. In a particular feature of the invention, the silicon-comprising fibres are single crystal fibres.
The silicon comprising fibres may have transverse dimensions in the range 0.08 to 0.5 microns, preferably 0.2 microns and a length in the range 12 to 300 microns preferably 100 microns. The fibres may have an aspect ratio of about 250:1. The fibres may have a substantially circular cross-section or a substantially non-circular cross-section.
The composite electrode of the first aspect is preferably provided as an anode.
The second aspect of the invention provides a method of fabricating a composite electrode according to the first aspect of the invention comprising contacting an active component with a current collector and heating to the reaction temperature of the active component and current collector. Alternatively, the active component and the current collector are heated to above their reaction temperature.
For the purposes of this invention, the reaction temperature is the temperature required to form a direct bond between the active component and the current collector, in particular to form to a compound between the active component and the current collector. It will be appreciated that the required temperature will vary depending on the identity (i.e. the chemical composition) of the active component and the current collector.
The method of the second aspect requires that the active component and the current collector are brought into contact. Preferably the active component and the current collector are contacted under an excess pressure of 5 pounds per square inch or above, more preferably 5 atmospheres or above.
It will be appreciated that it is advisable to avoid the formation of excess metal oxides at the contacting surfaces of the active component and/or the current collector. The method of the second aspect is therefore preferably carried out in an inert atmosphere, such as nitrogen, argon etc or in vacuo.
In a preferred feature of the second aspect there is provided a method of fabricating an electrode comprising contacting a silicon comprising active component with a copper current collector and heating to or above the silicon-copper alloy temperature.
As discussed in relation to the first aspect of the invention, the silicon comprising active component can be provided as fibres of silicon, said fibres being free or attached to a support. The fibres of the present invention can be created from a substrate (e.g. a chip or a wafer) comprising silicon by reactive ion etching, chemical reaction etching or galvanic exchange etching and, where applicable, detached by one or more of scraping, agitating or chemical etching.
The silicon-comprising active component can comprise undoped silicon, doped silicon or a silicon germanium mixture. The fibre can be single crystal silicon or single crystal silicon germanium. The fibres may extend from silicon-comprising particles.
The fibres of silicon can be contacted on the current collector in a composite or felt or a felt-like structure, that is a plurality of elongate or long thin fibres which crossover to provide multiple intersections, for example by being laid down in a random or disordered or indeed ordered manner. The arrangement of the active component in this fashion, reduces the problem of charge/discharge capacity loss. Typically the fibres will have a length to diameter ratio of approximately 100:1 and hence in an anode layer such as a composite anode layer, each fibre will contact other fibres many times along their length giving rise to a configuration where the chance of mechanical isolation arising from broken silicon contacts is negligible. The insertion and removal of lithium into the fibres, although causing volume expansion and volume contraction, does not cause the fibres to be destroyed and hence the intra-fibre electronic conductivity is preserved.
The active component and the current collector are brought into contact and form an interaction at the contacting surfaces. The interaction results in a change in the structure and/or composition of the active component and/or the current collector at the contacting surfaces, such that the active component and the current collector are bonded together. This bonding can be irreversible or reversible. Preferably, the active component and the current collector form a metal alloy at the contacting surfaces. The invention does not encompass merely contacting the active component and the current collector (i.e. by plating or depositing the active component on the current collector) and hence creates a very low electrical resistance pathway between the current collector and the active material.
The third aspect of the invention provides a method of fabricating a lithium rechargeable cell comprising the steps of creating an anode according to the second aspect of the invention and adding a cathode and an electrolyte. The method of the third aspect may further comprise adding a separator between cathode and the anode, and additionally further providing a casing around the cell.
The fourth aspect of the invention provides an electrochemical cell containing an anode according to the present invention. The fourth aspect in particular provides an electrochemical cell in which the cathode comprises a lithium-containing compound capable of releasing and reabsorbing lithium ions as its active material. More particularly, there is provided an electrochemical cell in which the cathode comprises lithium-based metal oxide or phosphate as its active material preferably LiCoO2 or LiMnxNixCo1-2xO2 or LiFePO4.
The fifth aspect of the invention provides a lithium rechargeable cell anode comprising an active component directly bonded to a current collector.
The sixth aspect of the invention provides a cell comprising an anode as described in the fifth aspect of the invention and a cathode. In particular, the cathode comprises lithium-based material, preferably the cathode comprises lithium cobalt dioxide.
The seventh aspect of the invention provides a device powered by a cell as described above.
The present invention is illustrated with reference to one or more of the following non-limiting examples:
The silicon fibres may be manufactured by detaching pillars from a substrate such as a chip or a wafer. In addition the manner of fabrication of the pillars may be provided by a simple repeatable chemical process.
One manner in which the pillars can be made is by dry etching, for example deep reactive ion etching of the type, for example, described in U.S. application Ser. No. 10/049,736 which is commonly assigned herewith and incorporated herein by reference. The skilled person will be familiar with the process such that detailed description is not required here. Briefly, however, a silicon substrate coated in native oxide is etched and washed so as to give a hydrophilic surface. Caesium chloride (CsCl) is evaporated on the surface and the coated substrate is transferred under dry conditions to a chamber of fixed water vapour pressure. A thin film of CsCl develops into an island array of hemispheres whose dimensional characteristics depend on initial thickness, water vapour pressure and time of development. The island array provides an effective mask after which etching is carried out for example by reactive ion etching leaving an array of pillars corresponding to the hemispherical islands. The CsCl resist layer is highly soluble in water and can be readily washed away.
Alternatively the pillars can be made by wet etching/using a chemical galvanic exchange method for example as described in our co-pending application GB 0601318.9 with common assignees and entitled “Method of etching a silicon-based material”, incorporated herewith by reference. A related method which may also be used has been disclosed in Peng K-Q, Yan, Y-J Gao, S-P, Zhu J., Adv. Materials, 14 (2004), 1164-1167 (“Peng”); K. Peng et al, Angew. Chem. Int. Ed., 44 2737-2742; and K. Peng et al., Adv. Funct. Mater., 16 (2006), 387-394.
In the preferred embodiment pillars of for example 100 microns in length and 0.2 microns in diameter are fabricated on and from a silicon substrate. More generally pillars of length in the range of 12 to 300 microns and diameter or largest transverse dimension in the range of 0.08 to 0.5 microns may be used to provide the fibres. According to the process the silicon substrate may be n- or p-type and, according to the chemical approach, and may be etched on any exposed (100) or (110) crystal face. Since the etching proceeds along crystal planes, the resulting fibres are single crystals. Because of this structural feature, the fibres will be substantially straight facilitating length to diameter ratio of approximately 100:1 and, when in a composite anode layer, allowing each fibre to contact other fibres many times along their length. The etching process can also be carried out either on very large scale integration (VLSI) electronic grade wafers or rejected samples of the same (single crystal wafers). As a cheaper alternative, photovoltaic grade polycrystalline material, as used for solar panels, may also be used.
In order to detach the pillars to obtain the fibres, the substrate, with pillars attached, is placed in a beaker or any appropriate container, covered in an inert liquid such as ethanol and subjected to ultra-sonic agitation. It is found that within several minutes the liquid is seen to be turbid and it can be seen by electron microscope examination that at this stage the pillars have been removed from their silicon base.
It will be appreciated that alternative methods for “harvesting” the pillars include scraping the substrate surface to detach them or detaching them chemically. One chemical approach appropriate to n-type silicon material comprises etching the substrate in an HF solution in the presence of backside illumination of the silicon wafer.
Once harvested, silicon fibres were washed in a dilute HF (1%) solution for several minutes. Water was removed by filtration, but sufficient water was retained to keep the silicon fibres wet. The fibres were dispersed on the copper foil (current collector). The silicon fibres coated copper substrate was then transferred into a Silicon Bonder chamber. At the vacuum of ca 2×10−6 mbar, a temperature of 400° C. and a pressure of 5 atmospheres, the silicon fibres annealed with copper for about 1 hour.
Alternatively dry and clean silicon fibres were placed on a copper substrate. The sample was transferred into a Rapid Thermal Annealing chamber and annealed in air or low flowing Argon ambient for 10 s at 800° C. After cooling, the sample was annealed in H2/N2 (10% H2) for 10 s at 800° C. to reduce the oxide.
Alternatively silicon fibres were coated onto a copper current collector to create a felt or felt-like structure and the sample passed through heated rollers to provide the required temperature and pressure to create the silicon-copper compound.
A particular advantage of the approach described herein is that large sheets of silicon-based anode can be fabricated, rolled if necessary, and then slit or stamped out subsequently as is currently the case in graphite-based anodes for lithium-ion battery cells meaning that the approach described herein can be retrofitted with the existing manufacturing capability.
Fabrication of the lithium-ion battery cell can be carried out in any appropriate manner, for example following the general structure shown in
It will be appreciated, of course, that any appropriate approach can be adopted in order to arrive at the approaches and apparatus described above. For example the pillar detaching operation can comprise any of a shaking, scraping, chemical or other operation as long as pillars are removed from the substrate to create fibres. Reference to silicon-based material includes silicon where appropriate. The fibres can have any appropriate dimension and can for example be pure silicon or doped silicon or other silicon-based material such as a silicon-germanium mixture or any other appropriate mixture. The substrate from which pillars are created may be n- or p-type, ranging from 100 to 0.001 Ohm cm, or it may be a suitable alloy of silicon, for example SixGe1-x. The fibres may be grown on particles of silicon such that they do not have to be detached. The fibres can be used for any appropriate purpose such as fabrication of electrodes generally including cathodes. The cathode material can be of any appropriate material, typically a lithium-based metal oxide or phosphate material such as LiCoO2, LiMnxNixCo1-2xO2 or LiFePO4. The features of different embodiments can be interchanged or juxtaposed as appropriate and the method steps performed in any appropriate order.
| Number | Date | Country | Kind |
|---|---|---|---|
| 0713896.9 | Jul 2007 | GB | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/GB2008/002453 | 7/17/2008 | WO | 00 | 2/26/2010 |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2009/010759 | 1/22/2009 | WO | A |
| Number | Name | Date | Kind |
|---|---|---|---|
| 3351445 | Fielder et al. | Nov 1967 | A |
| 4002541 | Streander | Jan 1977 | A |
| 4436796 | Huggins et al. | Mar 1984 | A |
| 4950566 | Huggins et al. | Aug 1990 | A |
| 5260148 | Idota | Nov 1993 | A |
| 5262021 | Lehmann et al. | Nov 1993 | A |
| 5660948 | Barker | Aug 1997 | A |
| 5907899 | Dahn et al. | Jun 1999 | A |
| 5980722 | Kuroda et al. | Nov 1999 | A |
| 6022640 | Takada et al. | Feb 2000 | A |
| 6042969 | Yamada et al. | Mar 2000 | A |
| 6063995 | Bohland et al. | May 2000 | A |
| 6235427 | Idota et al. | May 2001 | B1 |
| 6296969 | Yano et al. | Oct 2001 | B1 |
| 6334939 | Zhou et al. | Jan 2002 | B1 |
| 6337156 | Narang et al. | Jan 2002 | B1 |
| 6353317 | Green et al. | Mar 2002 | B1 |
| 6399177 | Fonash et al. | Jun 2002 | B1 |
| 6399246 | Vandayburg et al. | Jun 2002 | B1 |
| 6589696 | Matsubara et al. | Jul 2003 | B2 |
| 6605386 | Kasamatsu et al. | Aug 2003 | B1 |
| 6620547 | Sung et al. | Sep 2003 | B1 |
| 6887511 | Shima et al. | May 2005 | B1 |
| 6916679 | Snyder et al. | Jul 2005 | B2 |
| 7033936 | Green | Apr 2006 | B1 |
| 7051945 | Empedocles et al. | May 2006 | B2 |
| 7070632 | Visco et al. | Jul 2006 | B1 |
| 7094499 | Hung | Aug 2006 | B1 |
| 7147894 | Zhou et al. | Dec 2006 | B2 |
| 7192673 | Ikeda et al. | Mar 2007 | B1 |
| 7311999 | Kawase et al. | Dec 2007 | B2 |
| 7318982 | Gozdz et al. | Jan 2008 | B2 |
| 7348102 | Li et al. | Mar 2008 | B2 |
| 7358011 | Fukuoka et al. | Apr 2008 | B2 |
| 7378041 | Asao et al. | May 2008 | B2 |
| 7425285 | Asao et al. | Sep 2008 | B2 |
| 7476469 | Ota et al. | Jan 2009 | B2 |
| 7569202 | Farrell et al. | Aug 2009 | B2 |
| 7659034 | Minami et al. | Feb 2010 | B2 |
| 7674552 | Nakai et al. | Mar 2010 | B2 |
| 7767346 | Kim et al. | Aug 2010 | B2 |
| 7862933 | Okumura et al. | Jan 2011 | B2 |
| 8034485 | Dahn et al. | Oct 2011 | B2 |
| 20010023986 | Mancevski | Sep 2001 | A1 |
| 20030135989 | Huggins et al. | Jul 2003 | A1 |
| 20040072067 | Minami et al. | Apr 2004 | A1 |
| 20040126659 | Graetz et al. | Jul 2004 | A1 |
| 20040151987 | Kawase et al. | Aug 2004 | A1 |
| 20040166319 | Li et al. | Aug 2004 | A1 |
| 20040185346 | Takeuchi et al. | Sep 2004 | A1 |
| 20040197660 | Sheem et al. | Oct 2004 | A1 |
| 20040214085 | Sheem et al. | Oct 2004 | A1 |
| 20040224231 | Fujimoto et al. | Nov 2004 | A1 |
| 20040241548 | Nakamoto et al. | Dec 2004 | A1 |
| 20050042515 | Hwang et al. | Feb 2005 | A1 |
| 20050079414 | Yamamoto et al. | Apr 2005 | A1 |
| 20050079420 | Cho et al. | Apr 2005 | A1 |
| 20050118503 | Honda et al. | Jun 2005 | A1 |
| 20050191550 | Satoh et al. | Sep 2005 | A1 |
| 20050193800 | DeBoer et al. | Sep 2005 | A1 |
| 20050214644 | Aramata et al. | Sep 2005 | A1 |
| 20060003226 | Sawa et al. | Jan 2006 | A1 |
| 20060004226 | Machhammer et al. | Jan 2006 | A1 |
| 20060019115 | Wang et al. | Jan 2006 | A1 |
| 20060019168 | Li et al. | Jan 2006 | A1 |
| 20060024582 | Li et al. | Feb 2006 | A1 |
| 20060051670 | Aramata et al. | Mar 2006 | A1 |
| 20060057463 | Gao et al. | Mar 2006 | A1 |
| 20060088767 | Li et al. | Apr 2006 | A1 |
| 20060097691 | Green | May 2006 | A1 |
| 20060134516 | Im et al. | Jun 2006 | A1 |
| 20060134518 | Kogetsu et al. | Jun 2006 | A1 |
| 20060147800 | Sato et al. | Jul 2006 | A1 |
| 20060154071 | Homma et al. | Jul 2006 | A1 |
| 20060166093 | Zaghib et al. | Jul 2006 | A1 |
| 20060175704 | Shimizu et al. | Aug 2006 | A1 |
| 20060257307 | Yang | Nov 2006 | A1 |
| 20060263687 | Leitner et al. | Nov 2006 | A1 |
| 20060275663 | Matsuno et al. | Dec 2006 | A1 |
| 20060275668 | Peres et al. | Dec 2006 | A1 |
| 20060286448 | Snyder et al. | Dec 2006 | A1 |
| 20070026313 | Sano | Feb 2007 | A1 |
| 20070031733 | Kogetsu et al. | Feb 2007 | A1 |
| 20070037063 | Choi et al. | Feb 2007 | A1 |
| 20070048609 | Yeda et al. | Mar 2007 | A1 |
| 20070059598 | Yang | Mar 2007 | A1 |
| 20070065720 | Hasegawa et al. | Mar 2007 | A1 |
| 20070072074 | Yamamoto et al. | Mar 2007 | A1 |
| 20070087268 | Kim et al. | Apr 2007 | A1 |
| 20070099084 | Huang et al. | May 2007 | A1 |
| 20070099085 | Choi et al. | May 2007 | A1 |
| 20070105017 | Kawase et al. | May 2007 | A1 |
| 20070117018 | Huggins | May 2007 | A1 |
| 20070122702 | Sung et al. | May 2007 | A1 |
| 20070148544 | Le | Jun 2007 | A1 |
| 20070172732 | Jung et al. | Jul 2007 | A1 |
| 20070184345 | Neudecker et al. | Aug 2007 | A1 |
| 20070190413 | Lee et al. | Aug 2007 | A1 |
| 20070202395 | Snyder et al. | Aug 2007 | A1 |
| 20070202402 | Asahina et al. | Aug 2007 | A1 |
| 20070207080 | Yang | Sep 2007 | A1 |
| 20070207385 | Liu et al. | Sep 2007 | A1 |
| 20070209584 | Kalynushkin et al. | Sep 2007 | A1 |
| 20070212538 | Niu | Sep 2007 | A1 |
| 20070218366 | Kalynushkin et al. | Sep 2007 | A1 |
| 20070224508 | Aramata et al. | Sep 2007 | A1 |
| 20070224513 | Kalynushkin et al. | Sep 2007 | A1 |
| 20070238021 | Liu et al. | Oct 2007 | A1 |
| 20070243469 | Kim et al. | Oct 2007 | A1 |
| 20070264564 | Johnson et al. | Nov 2007 | A1 |
| 20070264574 | Kim et al. | Nov 2007 | A1 |
| 20070269718 | Krause et al. | Nov 2007 | A1 |
| 20070277370 | Kalynushkin et al. | Dec 2007 | A1 |
| 20080003496 | Neudecker et al. | Jan 2008 | A1 |
| 20080003503 | Kawakami et al. | Jan 2008 | A1 |
| 20080020281 | Kogetsu et al. | Jan 2008 | A1 |
| 20080038638 | Zhang et al. | Feb 2008 | A1 |
| 20080090149 | Sano et al. | Apr 2008 | A1 |
| 20080096110 | Bito et al. | Apr 2008 | A1 |
| 20080107967 | Liu et al. | May 2008 | A1 |
| 20080113271 | Ueda et al. | May 2008 | A1 |
| 20080118834 | Yew et al. | May 2008 | A1 |
| 20080124631 | Fukui et al. | May 2008 | A1 |
| 20080131782 | Hagiwara et al. | Jun 2008 | A1 |
| 20080138710 | Liaw et al. | Jun 2008 | A1 |
| 20080138716 | Iwama et al. | Jun 2008 | A1 |
| 20080145752 | Hirose et al. | Jun 2008 | A1 |
| 20080145759 | Sung et al. | Jun 2008 | A1 |
| 20080160415 | Wakita et al. | Jul 2008 | A1 |
| 20080176139 | White et al. | Jul 2008 | A1 |
| 20080206631 | Christensen et al. | Aug 2008 | A1 |
| 20080206641 | Christensen et al. | Aug 2008 | A1 |
| 20080233479 | Sung et al. | Sep 2008 | A1 |
| 20080233480 | Sung et al. | Sep 2008 | A1 |
| 20080241647 | Fukui et al. | Oct 2008 | A1 |
| 20080241703 | Yamamoto et al. | Oct 2008 | A1 |
| 20080248250 | Flemming et al. | Oct 2008 | A1 |
| 20080261112 | Nagata et al. | Oct 2008 | A1 |
| 20080305391 | Hirose et al. | Dec 2008 | A1 |
| 20090053589 | Obrovac et al. | Feb 2009 | A1 |
| 20090078982 | Rachmady et al. | Mar 2009 | A1 |
| 20090087731 | Fukui et al. | Apr 2009 | A1 |
| 20090101865 | Matsubara et al. | Apr 2009 | A1 |
| 20090117466 | Zhamu et al. | May 2009 | A1 |
| 20090186267 | Tiegs | Jul 2009 | A1 |
| 20090239151 | Nakanishi et al. | Sep 2009 | A1 |
| 20090253033 | Hirose et al. | Oct 2009 | A1 |
| 20090269677 | Hirose et al. | Oct 2009 | A1 |
| 20090305129 | Fukui et al. | Dec 2009 | A1 |
| 20100085685 | Pinwill | Apr 2010 | A1 |
| 20100092868 | Kim et al. | Apr 2010 | A1 |
| 20100124707 | Hirose et al. | May 2010 | A1 |
| 20100136437 | Nishida et al. | Jun 2010 | A1 |
| 20100285358 | Cui et al. | Nov 2010 | A1 |
| 20100297502 | Zhu et al. | Nov 2010 | A1 |
| 20100330419 | Cui et al. | Dec 2010 | A1 |
| Number | Date | Country |
|---|---|---|
| 101442124 | May 2009 | CN |
| 199 22 257 | Nov 2000 | DE |
| 103 47 570 | May 2005 | DE |
| 0 281 115 | Sep 1988 | EP |
| 0 553 465 | Aug 1993 | EP |
| 0 820 110 | Jan 1998 | EP |
| 1 011 160 | Jun 2000 | EP |
| 0 936 687 | Dec 2001 | EP |
| 1 231 653 | Aug 2002 | EP |
| 1 231 654 | Aug 2002 | EP |
| 1 258 937 | Nov 2002 | EP |
| 1 083 614 | May 2003 | EP |
| 1 313 158 | May 2003 | EP |
| 1 335 438 | Aug 2003 | EP |
| 1 289 045 | Mar 2006 | EP |
| 1 657 769 | May 2006 | EP |
| 1 850 409 | Oct 2007 | EP |
| 1 771 899 | Feb 2008 | EP |
| 1 657 768 | May 2008 | EP |
| 2 058 882 | May 2009 | EP |
| 2 204 868 | Jul 2010 | EP |
| 2 885 913 | Aug 2007 | FR |
| 980513 | Jan 1965 | GB |
| 1 014 706 | Dec 1965 | GB |
| 2 395 059 | May 2004 | GB |
| 2 464 157 | Jan 2010 | GB |
| 2 464 158 | Apr 2010 | GB |
| 02-209492 | Aug 1990 | JP |
| 6-283156 | Oct 1994 | JP |
| 10-046366 | Feb 1998 | JP |
| 10-83817 | Mar 1998 | JP |
| 10-199524 | Jul 1998 | JP |
| 2000-3727 | Jan 2000 | JP |
| 2000003731 | Jan 2000 | JP |
| 2000-173594 | Jun 2000 | JP |
| 2000-348730 | Dec 2000 | JP |
| 2001-291514 | Oct 2001 | JP |
| 2002-279974 | Sep 2002 | JP |
| 2002-313319 | Oct 2002 | JP |
| 2003-017040 | Jan 2003 | JP |
| 2003-168426 | Jun 2003 | JP |
| 04-607488 | Feb 2004 | JP |
| 2004-71305 | Mar 2004 | JP |
| 2004-095264 | Mar 2004 | JP |
| 2004-214054 | Jul 2004 | JP |
| 2004-281317 | Oct 2004 | JP |
| 2004-296386 | Oct 2004 | JP |
| 2004-533699 | Nov 2004 | JP |
| 2005-310759 | Nov 2005 | JP |
| 2006-505901 | Feb 2006 | JP |
| 2006-276214 | Oct 2006 | JP |
| 2006-290938 | Oct 2006 | JP |
| 2006-335410 | Dec 2006 | JP |
| 2007-165079 | Jun 2007 | JP |
| 2008-034266 | Feb 2008 | JP |
| 2008-186732 | Aug 2008 | JP |
| 2008-234988 | Oct 2008 | JP |
| 2009-252348 | Oct 2009 | JP |
| 2007-023141 | Feb 2007 | KR |
| 2007-0110569 | Nov 2007 | KR |
| 2008-038806 | May 2008 | KR |
| 1015956 | Aug 2000 | NL |
| 471402 | May 1975 | SU |
| 544019 | Jan 1977 | SU |
| WO 9933129 | Jul 1999 | WO |
| WO 0113414 | Feb 2001 | WO |
| WO 0135473 | May 2001 | WO |
| WO 0196847 | Dec 2001 | WO |
| WO 0225356 | Mar 2002 | WO |
| WO 0247185 | Jun 2002 | WO |
| WO 03063271 | Jul 2003 | WO |
| WO 03075372 | Sep 2003 | WO |
| WO 2004042851 | May 2004 | WO |
| WO 2004052489 | Jun 2004 | WO |
| WO 2004083490 | Sep 2004 | WO |
| WO 2005011030 | Feb 2005 | WO |
| WO 2005113467 | Dec 2005 | WO |
| WO 2005119753 | Dec 2005 | WO |
| WO 2006067891 | Jun 2006 | WO |
| WO 2006073427 | Jul 2006 | WO |
| WO 2006070158 | Jul 2006 | WO |
| WO 2006120332 | Nov 2006 | WO |
| WO 2007044315 | Apr 2007 | WO |
| WO 2007083152 | Jul 2007 | WO |
| WO 2007083155 | Jul 2007 | WO |
| WO 2007083155 | Jul 2007 | WO |
| WO 2007114168 | Oct 2007 | WO |
| WO 2007136164 | Nov 2007 | WO |
| WO 2008029888 | Mar 2008 | WO |
| WO 2008044683 | Apr 2008 | WO |
| WO 2008072460 | Jun 2008 | WO |
| WO 2008097723 | Aug 2008 | WO |
| WO 2008139157 | Nov 2008 | WO |
| WO 2009010757 | Jan 2009 | WO |
| WO 2009010758 | Jan 2009 | WO |
| WO 2009010759 | Jan 2009 | WO |
| WO 2009026466 | Feb 2009 | WO |
| WO 2009120404 | Oct 2009 | WO |
| WO 2009128800 | Oct 2009 | WO |
| WO 2010040985 | Apr 2010 | WO |
| WO 2010040986 | Apr 2010 | WO |
| WO 2010060348 | Jun 2010 | WO |
| WO 2010130975 | Nov 2010 | WO |
| WO 2010130976 | Nov 2010 | WO |
| Entry |
|---|
| Chan et al., “High-performance lithium battery anodes using silicon nanowires”, Dec. 16, 2007, Nature Nanotechnology, vol. 3, Jan. 2008, pp. 31-32. |
| WO 2006070158 A1, English Translation obtained from Google Translate on Nov. 14, 2013. |
| Lee et al., “Effect of Poly (Acrylic Acid) on Adhesion Strength and Electrochemical Performance of Natural Graphite Negative Electrode for Lithium-Ion Batteries”, Journal of Power Sources, 161(1), (2006), 612-616. |
| Key to Metal Aluminum-Silicon Alloys, www.keytometals.com/Article80. |
| Winter, et al., “Insertion Electrode Materials for Rechargeable Lithium Batteries”, Advanced Materials, 1998, 10, No. 10. |
| Kasavajjula et al., “Nano- and Bulk-Silicon-Based Insertion Anodes for Lithium-Ion Secondary Cells”, Journal of Power Sources, 163 (2007) 1003-1039. |
| Peng, et al., “Fabrication of Single-Crystalline Silicon Nanowires by Scratching a Silicon Surface with Catalytic Metal Particles”, Adv. Funct. Mater., 16 (2006), 387-394. |
| Barraclough et al., “Cold Compaction of Silicon Powders Without a Binding Agent”, Materials Letters 61 (2007) 485-487. |
| International Search Report for PCT/GB2008/002453 dated Oct. 9, 2008. |
| Written Opinion of the International Searching Authority dated Oct. 9, 2008. |
| Badel et al., “Formation of Ordered Pore Arrays at the Nanoscale by Electrochemical Etching of N-Type Silicon”, Superlattices and Microstructures, 36 (2004) 245-253. |
| Beaulieu et al., “Colossal Reversible Volume Changes in Lithium Alloys”, Electrochemical and Solid-State Letters, 4 (9) (2001) A137-A140. |
| Beaulieu et al., “Reaction of Li with Grain-Boundary Atoms in Nanostructured Compounds”, Journal of the Electrochemical Society, 147 (9) (2000) 3206-3212. |
| Besenhard et al., “Will Advanced Lithium-Alloy Anodes Have a Chance in Lithium-Ion Batteries?”, Journal of Power Sources, 68 (1997) 87-90. |
| Boukamp et al., “All-Solid Lithium Electrodes with Mixed-Conductor Matrix”, J. Electrochem. Soc.: Electrochemical Science and Technology, vol. 128, No. 4, (1981) 725-729. |
| Bourderau, et al., “Amorphous Silicon as a Possible Anode Material for Li-Ion Batteries”, Journal of Power Sources, 81-82 (1999) 233-236. |
| Colinge, Jean-Pierre, “Silicon-on-Insulator Technology: Materials to VLSI”, Chapter 2, SOI Materials, (1991), Cover page and p. 38. |
| Deal et al., “General Relationship for the Thermal Oxidation of Silicon”, Journal of Applied Physics, vol. 36, No. 12, (Dec. 1965) 3770-3778. |
| Feng et al., “Lithography-Free Silicon Micro-Pillars as Catalyst Supports for Microfabricated Fuel Cell Applications”, Electrochemistry Communications, 8 (2006). |
| Green et al., “Quantum Pillar Structures on n+ Gallium Arsenide Fabricated Using “Natural” Lithography”, Appl. Phys. Lett., 62 (3) (1993) 264-266. |
| Green et al., “Structured Silicon Anodes for Lithium Battery Applications”, Electrochemical and Solid-State Letters, 6 (5) (2003) A75-A79. |
| Green et al., “Mesoscopic Hemisphere Arrays for use as Resist in Solid State Structure Fabrication”, J. Vac. Sci. Technol. B 17(5) (1999) 2074-2083. |
| Yan et al., “Growth of Amorphous Silicon Nanowires via a Solid-Liquid-Solid Mechanism”, Chemical Physics Letters, 323 (2000) 224-228. |
| Shin et al., “Porous Silicon Negative Electrodes for Rechargeable Lithium Batteries”, Journal of Power Sources, 139 (2005) 314-320. |
| Li et al., “A High Capacity Nano-Si Composite Anode Material for Lithium Rechargeable Batteries”, Electrochemical and Solid-State Letters, 2 (11) (1999) 547-549. |
| Li et al., “The Crystal Structural Evolution of Nano-Si Anode Caused by Lithium Insertion and Extraction at Room Temperature”, Solid State Ionics, 135 (2000) 181-191. |
| Huggins, Robert A., “Lithium Alloy Anodes” in Handbook of Battery aterials, J.O. Besenhard Ed., Wiley-VCH, Weinheim, 361-381 (1999). |
| Chang et al., “Ultrafast Growth of Single-Crystalline Si Nanowires”, Materials Letters, 60 (2006) 2125-2128. |
| Kim et al., “Improvement of Silicon Powder Negative Electrodes by Copper Electroless Deposition for Lithium Secondary Batteries”, Journal of Power Sources, 147 (2005) 227-233. |
| Jianfeng et al., “Large-Scale Array of Highly Oriented Silicon-Rich Micro/Nanowires Induced by Gas Flow Steering”, Solid State Communications, 133 (2005) 271-275. |
| Lu et al., “A Study of the Mechanisms of Erosion in Silicon Single Crystals Using Hertzian Fracture Tests”, Wear, 186-187 (1995) 105-116. |
| Kleimann et al., “Formation of Wide and Deep Pores in Silicon by Electrochemical Etching”, Materials Science and Engineering, B69-70 (2000) 29-33. |
| Kolasinski, Kurt W., “Silicon Nanostructures from Electroless Electrochemical Etching”, Current Opinion in Solid State and Materials Science, 9 (2005) 73-83. |
| Pei et al., “Silicon Nanowires Grown from Silicon Monoxide Under Hydrothermal Conditions”, Journal of Crystal Growth, 289 (2006) 423-427. |
| Chen et al., “Selective Etching of Silicon in Aqueous Ammonia Solution”, Sensors and Actuators, A 49 (1995) 115-121. |
| Maranchi et al., “Interfacial Properties of the a-Si/Cu:Active-Inactive Thin-Film Anode Systems for Lithium-Ion Batteries”, Journal of the Electrochemical Society: 153 (6) (2006) A1246-A1253. |
| Nakahata et al., “Fabrication of Lotus-Type Porous Silicon by Unidirectional Solidification in Hyrdogen”, Materials Science and Engineering A 384 (2004) 373-376. |
| Niparko, J.K. (Editor), “Cochlear Implant Technology”, Pub., Lippincott Williams and Wilkins, Philadelphia, (2000) 108-121. |
| Ohara et al., “A Thin Film Silicon Anode for Li-Ion Batteries Having a Very Large Specific Capacity and Long Cycle Life”, Journal of Power Sources, 136 (2004) 303-306. |
| Peng et al., “Dendrite-Assisted Growth of Silicon Nanowires in Electroless Metal Deposition”, Adv. Funct. Mater., 13, No. 2 (2003) 127-132. |
| Peng et al., “Synthesis of Large-Area Silicon Nanowire Arrays via Self-Assembling Nanoelectrochemistry”, Adv. Mater., 14, No. 16 (2002) 1164-1167. |
| Peng et al., “Uniform, Axial-Orientation Alignment of One-Dimensional Single-Crystal Silicon Nanostructure Arrays”, Angew. Chem. Ind. Ed., 44 (2005) 2737-2742. |
| Peng et al., “Simultaneous Gold Deposition and Formation of Silicon Nanowire Arrays”, Journal of Electroanalytical Chemistry, 558 (2003) 35-39. |
| Canham, L. T., “Diffusion of Li IN Si”, Properties of Silicon, EMIS Datareviews Series No. 4 (1987) 454-462. |
| Qiu et al., “Self-Assembled Growth and Optical Emission of Silver-Capped Silicon Nanowires”, Applied Physics Letters, vol. 84, No. 19, (2004) 3867-3869. |
| Kim et al., “(110) Silicon Etching for High Aspect Ratio Comb Structures”, 1997 6th International Conference on Emerging Technologies and Factory Automation Proceedings, (1997) 248-252. |
| Sharma et al., “Thermodynamic Properties of the Lithium-Silicon System”, J. Electrochem. Soc.: Electrochemical Science and Technology, vol. 123 (1976) 1763-1768. |
| Qiu et al., “From S1 Nanotubes to Nanowires: Synthesis, Characterization, and Self-Assembly”, Journal of Crystal Growth, 277 (2005) 143-148. |
| Tokoro et al., “Anisotropic Etching Properties of Silicon in KOH and TMAH Solutions”, Proceedings of the 1998 International Symposium on Micromechatronics and Human Science (1998) 65-70. |
| Tsuchiya et al., “Structural Fabrication Using Cesium Chloride Island Arrays as a Resist in a Fluorocarbon Reactive Ion Etching Plasma”, Electrochemical and Solid-State Letters, 3 (1) (2000) 44-46. |
| Wagner et al., “Vapor-Liquid-Solid Mechanism of Single Crystal Growth”, Applied Physics Letters, vol. 4, No. 5 (1964) 89-90. |
| Lang, Walter, “Silicon Microstructuring Technology”, Materials Science and Engineering, R17 (1996) 1-55. |
| Liu et al., “Effect of Electrode Structure on Performance of Si Anode in Li-Ion Batteries: Si Particle Size and Conductive Additive”, Journal of Power Source, 140 (2005) 139-144. |
| Yan et al., “H2-Assisted Control Growth of Si Nanowires”, Journal of Crystal Growth, 257 (2003) 69-74. |
| Liu et al., “A Novel Method of Fabricating Porous Silicon Material: Ultrasonically Enhanced Anodic Electrochemical Etching”, Solid State Communications, 127 (2003) 583-588. |
| Zhang et al., “Bulk-Quantity Si Nanowires Synthesized by SiO Sublimation”, Journal of Crystal Growth, 212 (2000) 115-118. |
| Wong et al., “Controlled Growth of Silicon Nanowires Synthesized Via Solid-Liquid-Solid Mechanism”, Science and Technology of Advanced Materials, 6 (2005) 330-334. |
| Zhang et al., “Synthesis of Thin Si Whiskers (Nanowires) Using SiCl4”, Journal of Crystal Growth, 2006 (2001) 185-191. |
| Yoshio et al., “Electrochemical Behaviors of Silicon Based Anode Material”, Journal of Power Sources, 153 (2006) 375-379. |
| Zhang et al., “Catalytic Growth of x-FiSi2 and Silicon Nanowires”, Journal of Crystal Growth, 280 (2005) 286-291. |
| Ivanovskaya et al., “The Effect of Treatment of Cation-Selective Glass Electrodes With AgNO3 Solution on Electrode Properties”, Sensors and Actuators B 24-25 (1995) 304-308. |
| Peng et al., “Fabrication of Large-Area Silicon Nanowire p-n Junction Diode Arrays”, Adv. Mater. (2004), vol. 16, No. 1, 73-76. |
| Peng et al., “Silicon Nanowires for Rechargeable Lithium-ion Battery Anodes”, Applied Physics Letters (2008) vol. 93, No. 3, pp. 33105-1 to 33105-3. |
| De Angelis et al., “Water Soluble Nanoporous Nanoparticles for In Vivo Targeted Drug Deliver and Controlled Release in B Cells Tumor Context”, Nanoscale, 1020, vol. 2, p. 2230-2236. |
| Sharma et al., Diameter control of Ti-catalyzed silicon nanowires, J. Crystal Growth, 267, 613-18 (2004). |
| Tang et al., “High dispersion and electrocatalytic properties of platinum on well-aligned carbon nanotube arrays,” Carbon, 42, 191-97 (2004). |
| De Angelis et al., “Water Soluble Nanoporous Nanoparticles for In Vivo Targeted Drug Deliver and Controlled Release in B Cells Tumor Context”, Nanoscale, 1020, vol. 2, p. 2230-2236, (Year 2010). |
| Garrido, et al., The Role of Chemical Species in the Passivation of <100> Silicon Surfaces by HF in Water-Ethanol Solutions, J. Electrochem Soc., vol. 143, No. 12, 1996, p. 4059-4066. |
| Russo, et al., “A Mechanical Approach to Porous Silicon Nanoparticles Fabrication”, Materials 2011, vol. 4, p. 1023-1033. |
| Takami et al., “Silicon Fiber Formed on Silicon Without Using a Gas Process”, Journal of Applied Physics, vol. 91, No. 12, 2-5 (2002). |
| Ye et al., Controllable Growth of Silver Nanostructures by a Simple Replacement Reaction and Their SERS Studies, Solid State Sciences 11 (2009), p. 1088-1093. |
| Chan et al., “Surface Chemistry and Morphology of the Solid Electrolyte Interphase on Silicon Nanowire Lithium-Ion Battery Anodes”, Journal of Power Sources, 189(2), 1132-1140, (2009). |
| Chen et al., Binder Effect on Cycling Performance of Silicon/Carbon Composite Anodes for Lithium Ion Batteries, 36 (2006) 1099-1104. |
| Chen et al., “Effect of Vinylene Carbonate (VC) as Electrolyte Additive on Electrochemical Performance of Si Film Anode for Lithium Ion Batteries”, Journal of Power Sources, 174(2), 538-543, (2007). |
| Chevrier et al., “Methods for Successful Cycling of Alloy Negative Electrodes in Li-Ion Cells”, 220th ECS Meeting, Abstract #1237 (2011). |
| Choi et al., “Effect of Fluoroethylene Carbonate Additive on Interfacial Properties of Silicon Thin-Film Electrode”, Journal of Power Sources, 161(2), 1254-1259 (2006). |
| El Ouatani et al., “The Effect of Vinylene Carbonate Additive on Surface Film Formation on Both Electrodes in Li-Ion Batteries”, J. Electrochem. Soc., 156(2), A103-A113 (2009). |
| Han et al., “Neutralized Poly (Acrylic Acid) as Polymer Binder for High Capacity Silicon Negative Electrodes”, 220th ECS Meeting, Abstract #1250 (2011). |
| Heinze et al., “Viscosity Behaviour of Multivalent Metal Ion-Containing Carboxymethyl Cellulose Solutions”, Die Angewandte Makromolekulare Chamie 220, 123-132, (Nr. 3848), (1994). |
| Hochgatterer et al., “Silicon/Graphite Composite Electrodes for High Capacity Anodes: Influence of Binder Chemistry on Cycling Stability”, Electrochemical and Solid-State Letters, 11 (5) (2008) A76-A80. |
| Komba et al., “Functional Interface of Polymer Modified Graphite Anode”, Journal of Power Sources, 189, (2009), 197-203. |
| Komba et al., “Polyacrylate as Functional Binder for Silicon and Grapite Composite Electrode in Lithium-Ion Batteries”, Electrochemistry, 79(1), (2011), 6-9. |
| Komba et al., “Polyacrylate Modifier for Graphite Anode of Lithium-Ion Batteries”, Electrochemical and Solid-State Letters, 12(5), (2009), A107-A110. |
| Komba et al., “Study on Polymer Binders for High-Capacity SiO Negative Electrode of Li-Ion Batteries”, Journal of Physical Chemistry, 115, (2011), 13487-13495. |
| Lee et al., “Effect of Poly (Acrylic Acid) on Adhesion Strength and Electrochemical Performance of Natural Graphite Negative Electrode for Lithium-Ion Batteries”, Journal of Power Sources, 161(1) (2006), 612-616. |
| Li et al., “Sodium Carboxymethyl Cellulose: A Potential Binder for Si Negative Electrodes for Li-Ion Batteries”, Electrochemical and Solid-State Letters, 10(2) (2007), A17-A20. |
| Liu et al., “Enhanced Cycle Life of Si Anode for Li-Ion Batteries by Using Modified Elastomeric Binder”, Electrochemical and Solid-State Letters, 8(2) (2005), A100-A103. |
| Obrovac et al., “Structural Changes in Silicon Anodes During Lithium Insertion/Extraction”, Electrochemical and Solid-State Letters, 7(5), (2004), A96-A96. |
| Sugama, et al., “Nature of Interfacial Interaction Mechanisms Between Polyacrylic Acid Macromolecules and Oxide Metal Surfaces”, Journal of Materials Science, 19 (1984) 4045-4056. |
| Ui et al., “Improvement of Electrochemical Characteristics of Natural Graphite Negative Electrode Coated With Polyacrylic Acid in Pure Propylene Carbonate Electrolyte”, Journal of Power Sources, 173(1), (2007), 518-521. |
| Wen et al., “Chemical Diffusion in Intermediate Phases in the Lithium-Silicon System”, Journal of Solid State Chemistry, 37 (1981) 271-278. |
| Weydanz et al., “A Room Temperature Study of the Binary Lithium-Silicon and the Ternary Lithium-Chromium-Silicon System for use in Rechargeable Lithium Batteries”, Journal of Power Sources, 81-82 (1999) 237-242. |
| Yabuuchi et al., “Graphite-Silicon-Polyacrylate Negative Electrodes inlonic Liquid Electrolyte for Safer Rechargeable Li-Ion Batteries”, Advanced Energy Materials, 1, (2011), 759-765. |
| Zhang et al., “A Review on Electrolyte Additives for Lithium-Ion Batteries”, Journal of Power Sources, 162(2), 1379-1394, (2006). |
| Key to Metal Aluminum-Silicon Alloys, www.keytometals.com/Article80, Oct. 26, 2011. |
| Number | Date | Country | |
|---|---|---|---|
| 20100190057 A1 | Jul 2010 | US |
