Samsung Reveals Durable Nano Pt/Ru Catalyst to Improve Methanol Fuel Cell Performance

In U.S. Patent 7,642,217, Samsung SDI Co., Ltd. (Suwon-si, KR) reveals a platinum (Pt)/ruthenium (Ru) alloy catalyst with a lattice constant of 3.856-3.885 .ANG. and a particle size of 2-5 nanometers supported on a nano-carbon carrier.  According to inventors Seol-ah Lee, Chan-ho Pak and Dae-Jung Yoo, the Pt/Ru alloy catalyst is highly resistant to CO poisoning, thereby allowing for higher catalytic activity when used. That is, an electrode and a methanol fuel cell having a longer lifetime can be prepared using a smaller amount of the Pt/Ru alloy catalyst.

Examples of a carrier supporting the Pt and Ru atoms include a carbon-based carrier, zeolite, and silica/alumina, etc., preferably a carbon-based carrier and zeolite. Examples of the carbon-based carrier include graphite, carbon powders, acetylene black, carbon black, activated carbon, mesoporous carbon, carbon nanotubes, carbon nanofibers, carbon nanohorns, carbon nanorings, carbon nanowires, or fullerene (C₆₀).

A total concentration of Pt and Ru may be 60-80% by weight of the Pt/Ru alloy supported catalyst. If the total concentration of Pt and Ru is less than 60% by weight of the Pt/Ru alloy supported catalyst, a thickness of a catalytic layer in an anode increases, and thus an electrical resistance excessively increases. If the total concentration of Pt and Ru is greater than 80% by weight of the Pt/Ru alloy supported catalyst, the catalyst particles are agglomerated, and thus the specific surface area decreases and the utilization efficiency of the catalyst decreases.

FIG. 1 is a schematic view illustrating a mechanism that a Pt/Ru alloy nano-catalyst exhibits a resistance to CO poisoning; 

FIG. 2 is a flow diagram illustrating a method of preparing the Pt/Ru alloy nano-catalyst by Samsung's Method

FIG. 3A is a transmission electron microscopic (TEM) image of a Pt/Ru alloy nano-catalyst and
FIG. 3B is a TEM image of a Pt/Ru alloy nano-catalyst by Samsung’s method

Ballard Power System Reports New Agreement to Supply Daimler AG with Fuel Cell Products for Vehicles

On December 22^nd Ballard Power Systems (TSX: BLD; NASDAQ: BLDP) announced a supply agreement with Daimler AG for FCvelocity® fuel cell products for Daimler AG's fuel cell car and bus programs. The agreement provides for minimum revenue of approximately $24 million over eighteen months from April 2010, with roughly equal distribution in 2010 and 2011. John Sheridan, Ballard's President & CEO said, "We are very pleased to be working with Daimler AG, a clear global leader in fuel cell car and bus programs."

He continued, "Automotive is one of the most demanding power applications in terms of efficiency, reliability and safety. As such, this major fuel cell order for the automotive market provides further testimony of Ballard's leading fuel cell product capabilities for commercial clean power applications in backup power, distributed generation and material handling."

On December 21^st Ballard Power announced that it has closed an agreement effective today with a financial institution to monetize its rights under the Share Purchase Agreement with Ford Motor Company (Ford) relating to Ballard's 19.9% equity interest in Automotive Fuel Cell Cooperation Corp. (AFCC). Ballard will receive total gross proceeds of approximately $44.5 million: a $37 million payment today and a further contingent payment of $7.5 million due upon maturation of the Share Purchase Agreement on or before January 31, 2013. Ballard's receipt of the contingent payment is subject to the financial institution's rights in the transaction remaining unsubordinated.

Bruce Cousins, Ballard's Chief Financial Officer said, "Given the recent improvement in public debt market conditions and Ford's credit rating, we believe that this is the appropriate time to monetize this non-core investment".

John Sheridan, Ballard's President & CEO said, "The cash proceeds from this transaction bolster Ballard's strong balance sheet and strengthen our positioning to execute our clean energy growth priorities in backup power, supplemental power, distributed generation and motive power applications".

Ballard expects to book a gain associated with this transaction of approximately $34 million in its fourth quarter results. This transaction does not affect Ballard's business relationships with AFCC, Daimler, Ford, and their affiliates. Ballard will continue to supply technical services and fuel cell components and modules.

As part of the monetization agreement, Ballard has pledged its shares in AFCC and assigned its right to "put" or sell those shares to Ford for $65 million plus interest after January 31, 2013. The value of the monetization of the agreement with a financial institution was determined based on a number of variables, including Ford's cost of borrowing, expected future London Interbank Offered Rates (LIBOR), time remaining to the Share Purchase Agreement's maturity date and general market and other conditions. All required approvals from Daimler AG, Ford and AFCC were received prior to the closing of this transaction. Ballard's intellectual property rights are unaffected by this transaction.

Lazard Freres & Co. LLC acted as a financial advisor to Ballard for the transaction.

Canon Water Repellent Nano-Catalyst Layer Improves Fuel Cell Performance and Lowers Cost

FIG. 8 is an atomic force microscope (AFM) image of Canon's water repellent nano-catalyst layer surface for polymer electrolyte fuel cells to power small electronic equipment, such as mobile phones,  notebook personal computers, or digital cameras.

Canon (Tokyo, JP) inventors Shinnosuke Koji, Kazuya Miyazaki, Yoshinobu Okumura, and  Kaoru Ojima created a water repellent nano-catalyst layer for a polymer electrolyte fuel cell.  The hydrophobic property is imparted even to the inside of fine pores of the catalyst layer to improve water evacuation performance but in such a way that the effective surface area and the catalyst utilization ratio can be increased.

The catalyst shows improved evacuation performance of the water produced during the electrochemical reaction of hydrogen and oxygen.  It has a stable performance over a long period of time. It can be used to manufacture a more stable polymer electrolyte fuel cell “at a low cost,” according to Canon inventors in U.S. Patent Application 20090311578. 

In the polymer electrolyte fuel cell, in general, a fluororesin-based ion exchange membrane is used as a solid electrolyte of a proton conductor, and a catalyst, such as platinum or platinum-alloy fine particles having high catalyst activation, is used for promoting a hydrogen oxidation reaction and an oxygen reduction reaction. The electrode reaction occurs in a so-called three-phase interface (electrolyte--catalyst electrode--fuel) in a catalyst layer. In this case, there is a problem in that a voltage is gradually reduced as power generation time elapses, and power generation finally stops.

This is caused by a so-called "flooding phenomenon" in which water generated in the reaction is retained in spaces of the catalyst layer and the water fills the spaces in the catalyst layer, thereby inhibiting the supply of a fuel gas serving as a reactant. As a result, a power generation reaction stops. In particular, the flooding phenomenon is liable to occur in the catalyst layer on a cathode side, where the water is generated.

In order to prevent the flooding phenomenon, it is necessary to make the inside of the catalyst layer hydrophobic. There is a generally known method of mixing, with a catalyst layer including catalyst fine particles and a proton-conductive electrolyte, fluororesin-based particles, such as polytetrafluoroethylene (PTFE), together with a solvent or a surfactant. However, this method has a problem in that the three-phase interface is reduced due to the presence of the PTFE particles, so that output power is also reduced.  The Canon water repellant catalyst does not reduce the three-phase interface.

The water repellent coating film includes molecules of a fluorine-based compound with a molecular weight of 10,000 or less. When the molecular weight is larger than 10,000, it is difficult to make the inside of the micro space in the porous catalyst layer hydrophobic.

In order to maximize the reaction surface area, the catalyst forming the catalyst layer includes catalyst particles or catalyst-carrying particles each with a particle diameter of several nm to several tens of nm, or a nano structural body formed of the catalyst nanoparticles. The catalyst layer constitutes a porous body and has fine pores each having a diameter of several nanometers (nm) to several hundreds of micrometers.

The fluorine-based is used as a precursor of the water repellent coating film, thereby enabling the formation of the water repellent coating film also on the inside of the  nanometer and micrometers  pores.  The inside of the micro space is also made hydrophobic, so the catalyst utilization ratio is increased, thereby enabling driving with a high output power for a long time. A nano structural body catalyst may be adopted irrespective of the size or the shape of the catalyst.

Examples of the fluorine-based compound with at least one polar group and with a molecular weight of 10,000 or less include perfluoro alcohol, perfluoro carboxylic acid, Demnum (manufactured by Daikin Industries, Ltd.) used as a lubricating oil, surface treating agents, such as Krytox (manufactured by DuPont) and Novec EGC-1720 (manufactured by 3M).

The catalyst nanoparticles are manufactured from  a platinum oxide, a composite oxide of the platinum oxide and an oxide of a metallic element other than platinum.  Platinum is obtained by performing a reduction treatment of a platinum oxide or a multi-metal platinum composite.