METHOD OF MANUFACTURE OF AN ELECTRODE FOR A FUEL CELL

In one embodiment, a nickel metal to be deposited, with the, cobalt, platinum, rhodium, ruthenium, rhenium and palladium selected from the group consisting of of one or more metals or, alloy at least one of these metals. Including said it is preferred that a nickel metal. These metals of both an anode and a cathode finds suitable application in for use in the manufacture of. said metal to be deposited, with a plating layer to the resin in solution is provided by metal precursor. Said metal precursor is a metal salt is preferably in an, said plating solution dissolved in free metal ion should can provide.

In another embodiment, said gas diffusion co-together metal and said particulate material a yttria stabilized zirconia (YSZ), ceria stabilized zirconia (CeSZ: ceria stabilised zirconia), cerium gadolinium oxide, samarium-doped ceria, lanthanides mixed gallium oxide, lanthanum strontium manganate, YSZ-stabilized lanthanum strontium manganate, barium cobalt oxide, la-strontium iron-cobalt oxide, la-strontium cobalt-copper oxide, samarium-strontium cobalt oxide and mixtures thereof can be selected from the group consisting of.

Anode connected to the positive terminal of according, said gas diffusion co-together metal and said particulate material a yttria stabilized zirconia (YSZ), ceria stabilized zirconia (CeSZ), cerium gadolinium oxide, samarium-doped ceria, lanthanides mixed gallium oxide and mixtures thereof can be selected from the group consisting of. According cathode, said metal with a particulate material said co-gas diffusion La_0.85 Sr_0.15 MnO₃ such as lanthanum strontium manganate, YSZ-La_0.85 Sr_0.15 MnO₃ and YSZ-La_0.8 Sr_0.2 MnO₃ YSZ-stabilized such as lanthanum strontium manganate, barium cobalt oxide BaCoO₃, (La, Sr)₁ (Fe, Co)₁ O_3-δ such as la-strontium iron-cobalt oxide, (La, Sr)₁ (Fe, cubic)₁ O_3-δ such as la-strontium iron-copper oxide, Sm_0.6 Sr_0.4 CoO₃ such as samarium-strontium cobalt oxide and mixtures thereof can be selected from the group consisting of.

A particulate material said industrial field of application according to design and fuel cells (micro m) 0.1 to 50 micrometers, more preferably 0.2 to 40 micro m material may have a particle size ranging from.

Particulate material and metal on semiconductcr electrode substrate said co-deposition to form electrodes of a fuel cell. Said electrode substrate of a fuel cell's electrolyte or forming the interconnect it is preferable that the. Said electrolyte or interconnect the electrode material on the directly on for a fuel cell capable of simplifies the structure. Therefore, a continuous electrode substrate said is preferably, i.e., particulate substrate (monolith) monolith rather than such as non-particulate electrode substrate using the is preferably not less. Said can take aspect of any substrate. For example, plane to fit design SOFC may be a planar, or cylindrical SOFC can be a cylindrical to fit design.

In one embodiment, said electrode substrate the lanthanum chromate, doped lanthanum chromate, doped lanthanum gallate, lanthanum manganate, doped lanthanum manganate, yttria stabilized zirconia (YSZ), ceria stabilized zirconia (CeSZ), cerium gadolinium oxide, samarium-doped ceria, mixed lanthanum and gallium oxide and mixtures thereof is selected from the group consisting of. Alternatively, according to design a fuel cell electrode substrate said chromium-based, metal, such as system and nickel iron or metal substrate can be polymer substrate. Lanthanum chromate, doped lanthanum chromate, lanthanum manganate and doped lanthanum manganate a fuel cell interconnect as is materials a suitable substrate. Yttria stabilized zirconia (YSZ), ceria stabilized zirconia (CeSZ), cerium gadolinium oxide, samarium-doped ceria and mixed, at a gallium oxide and lanthanides as electrolytes in a fuel cell is materials a suitable substrate.

Said plating solution in said metal precursor in reducing agent capable of reducing ascorbic acid of metals into metal should. Hypophosphite reducing agent (hypophosphite) for including said but is preferably, according to the metal to be deposited, with may be alternatives are used. Preferably said oh phosphoric acid saltoh with phosphoric acid natriumoh phosphoric acid salt such as.

In addition the plating solutions described solvent includes said. Said solvent reducing agent and said disposed to be submerged into the molten metal precursor should. Said solvent is preferably not less water.

In another embodiment, the plating solutions described metallization step, during said (c) said particulate material, said metal precursor and said group of one or more reducing agent are supplied with the. Furthermore, the plating solutions described metallization step, (c) during said reducing agent is supplied from an.

In another embodiment, said particulate material in said plating solution, said metal precursor and said reducing agent group of at least one member selected among the concentration of metallization step, is changes during (c).

In another embodiment, the step of the present invention method pre-processing of a the substrate prior to (b) includes. Said which a pretreatment step (degreasing), electrolyte (electrocleaning) degreasing, etching, masking, activation and cleaning selected from the group consisting of of one or more reducing steps in a may include a.

Said when the an activation step a pretreatment step, and the dyeing steps on a substrate said electroless plating catalyst depositing a may comprise an. Said electroless plating is preferably not less palladium catalyst. Said active steps will said electroless plating catalyst or contemporaneously with the or during deposition of said substrate additionally comprises the step of is facilitated by making the processes (sensitizing) can be. The in particular, when said substrate is in a non-conductive, for example, YSZ substrate is said fuel the useful if the cell electrolyte. Tin chloride (II) solution is facilitated by making the processes steps will said said step of treating the substrate including it is preferred that a.

In another aspect of the present invention, described herein for fuel cell manufactured according to method of anode or cathode an electrode such is provided.

Only now are embodiment in the embodiment of the present invention, not limited to, the appended in reference to drawing will by describing the.

Electroless metal deposition acids to epoxygenated fatty acids therein external current without using a chemical reduction on a substrate by a metal, such as cobalt nickel for chemically electroplating.. The plating solutions described the material surface and an electrolessly publicly known generally metal ion source such as dissolved in solvent metal precursor and includes the reducing agents and. Said. water-solvent is typically an. Said electroless plating solution required, so that the finally obtained solution pH buffer solution and a for providing and to prevent precipitation in a solution of metal ions which can be may include further complexing agent. Stabilizer, gloss number, alloy number, in addition said surfactant may be present plating solution.

Said metal deposition a reducing agent its own effect or power by a power supply of a reductant said metal ions is metallic form, with which is reduced includes. Said hypophosphite reducing agent, amine can be borohydrides or gene confers sensitivity to the tyrosine kinase. Once when disclosure, said deposited onto the surface of the substrate to the molten metal is catalyst self is deposited by. For example, according to known as a raw material of the nickel from aqueous solution of the nickel (II) hypophosphite ion can be is deposited onto a substrate:

H₂ PO₂^- + H₂ O → H₂ PO₃^- + 2H_abs (I)

Ni²⁺ + 2H_abs → Ni + 2H⁺ (II).

In present implementations, hypophosphite and reaction product of said (absorbed hydrogen, H_abs) a reducing agent in solution rather than self react with nickel (II).. A metal precursor it is preferred that a nickel chloride (II). oh it is phosphoric acid natrium. and it is more preferred to set said reducing agent. Said solvent can be water.

Simultaneously, known as a raw material of the as described (III), said part being absorbed oh phosphoric acid salt hydrogen and response to depositing phosphorus substrate, water and hydroxy ions can be produced:

H₂ PO₂^- + H_abs → H₂ O + OH^- + P (III).

As a result, in the alloying nickel-phosphorus is deposited together may be loaded with. Said content in of deposits by pharmacological tests listed in the ISO4527 Annex D can be determined. Conventional the deposition of plating solutions according to properties of 2 to 14 weight %. of a phosphorous bearing. (III) in addition to said known as a raw material of the, oh phosphoric acid salt a portion known as a raw material of the water as described (IV) is oxidizable by a phosphite form a space of the housing, and generation of hydrogen can be:

H₂ PO₂^- + H₂ O → H₂ PO₃^- + H₂ (IV).

Nickel and having a wide variety of compositions, such alloy-acids of phosphorus electroless nickel deposition process having a phosphorous content the ability of said change in performance characteristics minute structure and of deposits thus it is eminently to the useful in particular. Therefore, electroless plating electrolytic cell condition and electrolytic cell according to composition, conductive metal is amorphized, crystalline or semi-crystalline metal. it is capable of being plated.

For example, a phosphorus content more than about 10 weight % including electroless nickel deposits can be amorphous, while a phosphorus content less than about 7 weight % microcrystalline structure including vapor deposit material may have a weight % a phosphorus content of between. 7 to 10 including deposition contains substantially no semi-crystalline structure is. Said degree of characteristics or crystalline amorphous of deposits growth process of deposits said electroless plating solution which affect the amount of the particular position by additives added to in composition can vary with.

Amorphous deposition, in particular very is amorphous mouth stepfather vapor deposit (intergranular corrosion) a place foroptical capable of acting as on the substrate, interlaying because less is tempered in an atmosphere can, electro-deposition conventional crystalline made by the process structured by relative deposition provides.

In a specific embodiment at alternatively, amine [...] reductant on can be used. For example, die methylamine [...] by reduction of nickel chloride (II) is known as a raw material of the. shown in an (V):

(CH₃)₂ HNBH₃ + 3H₂ O + NiCl₂ → (CH₃)₂ NH + H₃ BO₃ + 2H₂ + 2HCl + Ni (V).

In the present invention, in addition said suspension of particulate material present in plating solution. A suspension of particulate material said for example, mechanical mixing, e.g. magnetic or a rotary type feeding powder deodorizing agent evenly through the entire plating solution is over. Said said vapor deposit of nickel plating solution introducing particulate material suspended on the substrate particles of the co-deposited nickel and together..

Said co-deposited uniformly a particulate material of nickel and of uniform thickness and an which, porosity and deep even, even for. surface knob section forms an upper recess (recess). The uniformity of the coating said form a re-finishing surface of substrate, to increase surface area this method is supplied be roughened. The in addition said to production line operation the final coating, which can be applied to satisfy a strict dimensional tolerances (dimensional tolerance). means that they can be.

Said metallization step, is provided, said metal precursor in plating solution, concentration of reducing agent and particulate material since the available for consumption these components is reduced and controlled in a more precise. As a result, said are to one or more of those components during metallization step, can be added to said plating solution. Said regularly component or continuous or interval or irregularly said plating solution can be added to. Said component used for said plating solution is preferably added are dissolved in the solvent, ..

During metallization step, said plating solution from said said initial metallization step, the amount of induced by such a specific on said component concentration can be sufficient to. Or, said plating solution during metallization step, said amount of from or can be modified in, and the time interval at which the component are added which can be adapted to change, the co-deposited in the coating specific depth for adjusting the concentration of an element said..

For example, metal with co-particulates that deposit the concentration of material, said metal to co-deposited particulate material of point-welding part of recent the substrate ratio of to highest memory state in most at the beginning of metallization step, may be bigger. In this case, said particulate material and substrate CTE if voices is as similar as a, in other words, , both particulate material substrate and includes if YSZ, CTE-coating and/or adjacent to a substrate, deposition of said said substrate and the socket and also make matching close than repeated process and minimizes stresses that may heat during penetration hole while moving up and down. Said particulate material with a method comprising reducing a metal the step is formed between the co-deposition from a remote coating zone can be increased, is to an anode conductive required electrical which is for providing a, . is similarly treated in addition vice versa.

Said metallization step, generally, including plating dropper said plating solution is carried out by immersing said substrate. Aqueous from the plating solution nickel in one embodiment the tin plating, said plating is heating generally an electrolyzer. Said plating an electrolyzer to provide optimum rates of deposition for at a temperature range of 80 to 100 °C preferably that which is being heated, more preferably 85 to 95 °C, most preferably less than about 90 °C. is heated to a temperature of.

Alternatively, said metallization step, said only a portion of a substrate by contacting the plating solution may be performed, for example, only a portion of said substrate said. immersing plating solution.

The monitor said electroless plating, one or more a pretreatment step can be is performed. Said substrate before electroless plating said ultrasound or dip-in a aqueous or non-aqueous intake be debinded. it is desirable that.

When the conductive substrate electrode substrate using the, the field of a publicly known method may be degreased as the electrolyte.

In another embodiment, as publicly known to the field of etching with a mask a pretreatment step to said electrode in said electrode substrate only part of the is to enter into contact with the plating solution. As a result, a particulate material metal and not covered with the mask said obtained an electrode substrate a thickness co-only of zones.

Anode such as surface properties the operational characteristics of fuel cell electrodes and to associated is connected to the semiconductor layer.. Electrode in order to improve the efficiency, greater surface area must be increased a reaction rate, so.. Said further surface properties the surface area of the electrode has a greater roughness than a data method increasing the porosity and method one or two method using both can be increased by. These method both electrode surface area pushes back and stably combined efficient computer can be maximized as there is reaction rates may provide a.

As described above, said co-deposited has a thickness uniform coating, . surface knob section forms an upper [...] and pore deep. Therefore, the surface area of the electrode, for roughening surface of method and substrate porosity increasing the using both one or method can be increased at the.. An electrode substrate and apparatus for etching glass plate surface is, for example, wet or a dry phase techniques can be achieved by.

Wet etching liquid etching solution (etchant) user uses, process management and for excellent is stirred this can be achieved. For example, sulphuric acid and fluorine installed inside a desalting tub dissipation YSZ solution including one or both can be used to etch substrate.

Dry etching on said electrode substrate for etching the surface of use of plasma or ion flow. Plasma etching electrically neutral preparing hybridoma producing the anti-free radical are in creating the, reaction surface of said electrode by etching. The sputter etching said substrate to the direction reverse to the normal inert gases with different potent ion flow is impacted the to collision with atoms of said substrate surface. Alternatively, polishing blasting (abrasive blasting), such as air compression technique using pressurized gas and polishing medium said surface stripping may be used in.

Insulated electrode on a substrate-etched by said electroless plating is disclosure hole for electrode substrate is necessarily. This is facilitated by making the processes and may be brought about by cataiyzed processes.. Generally, palladium metal is used as a catalyst, in.. Said said catalyst metal plating the outer a current source, the request without self outputs a relay driving signal. the substrate is rotated to form a catalytic reactor. Palladium particles a single, double or multiple stage reaction can be deposited on the surfaces of the insulator. Single-step in, said insulated electrode substrate in the form hydrosol SnCl₂ and PdCl₂ of processing mixed acid solution according to (VI) are known as a raw material of the can be depositing palladium:

SnCl₂ + PdCl₂ → SnCl₄ + Pd (VI).

Said colloidal has Pd metal said form is the suction hole electrode substrate. Said adsorption colloidal Pd particles during subsequent metal metallization step, functions, as catalysts for metal deposition.

Alternatively, the acidified, said insulated electrode substrate SnCl₂ after continuously solution is facilitated by making the processes, dual--phase process PdCl₂ can be catalyzed solution, selectively cleaning between the material may have a step. An electrode substrate surface activation electrode substrate when the substrate becomes conductive can be omit.

Other advantages of the present invention method as well as a conductive electrode substrate, insulating electrode substrate using the as described above active, insulated electrode substrate metal and increase volume and the ball particulate material is that they can be-deposition.

The preprocessed electrode substrate said one or more of sub-processing steps between the steps is cleaned in between metallization step, winding it is preferable that the. Due to the application of a pretreatment step cleaning the residual contaminant are removed for metallization step, provide surfaces for a pure. Class reagent for appropriate analytical cleaning solvent or or high purity deionized water be.

Electroless plating applied by said thickness of the metal coating member is plated and/substrate immersed in the electrolytic cell is dependent on the time. Nickel plating step per hour deposition rates of 16 to 20 micro m is is generally. The thickness of deposits can be measured according to ASTM B487.

In the embodiment 1 : production on conductive substrate

25 millimeter × 20 millimeter×1mm scale and the abrasive is a brass electrode substrate (AMT Limited) for 15 minutes in 60 °C Slotoclean FSA (Schloetter Company Limited) and be debinded solution, deionized water at room temperature be debinded and scrubbing of the electrolyte the pre-processing section.

Plating dropper Slotonip 2010 (Schloetter Company Limited) 2 micro m nominal particle size of yttria 8 weight % as stabilizers applying a (Unitec Ceramics Limited) 50g / ℓ YSZ powder suspended mechanically agitated same produced when the electroless nickel plating solutions using nickel plating is performed for all the. Furthermore, said solution using stirrer hot plate was heated to a temperature of 89 °C. Furthermore, said brass substrate said immersing plating solution was 30 minutes. After removing the plating from an electrolytic cell, said substrate coated with a film are deionized water which washes the-useless error, then propane-2-ol (class reagent for analysis) both at room temperature performed for all the then being washed with but. Furthermore, nickel and YSZ co-deposited substrate to dry to in air across the surface of a electrode substrate a YSZ and nickel co-deposited coating are obtained.

In the embodiment 2 : production on insulating substrate

The commercially available YSZ coating polymer films electrode substrate (Napier University) and YSZ fuel cell electrode substrate (Fuel Cell Scotland) in 60 °C Slotoclean FSA (Schloetter Company Limited) and be debinded solution for 15 minutes, then deionized water at room temperature by washing the pretreatment section. Furthermore, 200g / ℓ Uniphase PHP pre-catalyst said insulated electrode substrate (AlfaChimici) solution in 20 milliliter / ℓ HCl solution 15 minutes and 20 °C step of immersing the double including the activated by step process is facilitated by making the processes to substrates are obtained. Furthermore, said with electrode substrate including pre-catalyst ℓ Uniphase PHP catalyst (AlfaChimici)/ 20 milliliter solution adding an solution, 15 minutes in raised from a 35 °C temperature is facilitated by making the processes and catalyzed with electrode substrate are obtained. Furthermore, said electrode substrate in which a catalyzed and is facilitated by making the processes pre-processing of a and removing them from the solution at room temperature was then being washed with deionized water.

Next, plating dropper Slotonip 2010 (Schloetter Company Limited) 2 micro m nominal particle size of yttria 8 weight % as stabilizers (Unitec Ceramics Limited) powder ℓ YSZ/50g applying a same mechanically agitated suspended when the electroless nickel plating solutions manufacturing processes and the cost of production. Furthermore, said solution using stirrer hot plate was heated to a temperature of 89 °C. Furthermore, and the catalyst activated said metallized dielectric with electrode substrate said immersing plating solution was 30 minutes. After removing the plating from an electrolytic cell, said substrate coated with a film are deionized water which washes the-useless error, then propane-2-ol (class reagent for analysis) both at room temperature performed for all the then being washed with but. Furthermore, nickel and YSZ electrode substrate in which a co-deposited to a dried in the air.

YSZ, and nickel also of substrates that are not plated is co-deposited with electrode substrate using microscope Cambridge Stereoscan 90 a scanning electron microscopy (SEM) was subject to analysis by. Co-deposited used as the material for electrode substrate in which a, Ni/YSZ over the whole surface of the substrate consisting of a homogenous deposition of the composite can be to know that the.

In particular, Figure 2 shows a 3030 YSZ powder the uncoated also outputs a signal corresponding to is a scanning electron micrographs. Figure 3 shows a a are also prepared to exemplify embodiment, YSZ coating polymer films (Napier University) substrate co-deposited coating of nickel and YSZ 5000 outputs a signal corresponding to is a scanning electron micrographs. Through electric communication of the transistor of Figure 3 and also 2 YSZ coating polymer films YSZ particles and nickel on a electrode substrate parameters co-deposition occurs been can be viewed.

Composite formation of deposition using i-Scan Microimaging system energy dispersing X-ray analysis (EDX) is confirmed. Also Figure 4 shows a conventional electroless nickel coating of EDX spectrum is in. Figure 5 shows a also nickel and YSZ is co-deposited YSZ coating polymer films to a substrate electrode in the EDX spectrum. Also 4 nickel from coating comparison of Figure 5 and corresponding to a transition peak is observed with a main body. Figure 5 in addition co-deposited YSZ particulate material from yttrium, zirconium and oxygen transition peaks show. Similar spectrum the corresponding co-deposited YSZ fuel cell electrode substrate (Fuel Cell Scotland) been obtained to. Of said electrode substrate in which a co-deposited EDX spectrum a complex also been show deposition is obtained. SEM with an analysis EDX spectrum a combination result, uniformly coating the surface of said substrates been has been confirmed.

Fisherscope XDL-Z X-ray fluorescent device using more further analyze results said substrate, said obtained of the structured coating micro m a thickness of greater than about 9 to 11 can be to know that the is. Co-deposited YSZ coated electrode substrates in SOFC anode/electrolyte was suitable for use as a.

In the embodiment 3 : production on insulating substrate etched

Series of YSZ electrode substrates BS EN ISO 4288:1998 Taylor-Hobson 5-60 Talysurf device according to (Fuel Cell Scotland) surface roughness of it was determined that using a crust-less of. 1.3 micro m×3.8 micro m a like structure, diamond end the stage stylus across the surface of a electrode substrate establishment of a 6 millimeter distances it does but drawing to its constant-speed s/0.5 millimeter, said stylus across the surface electrode said its traverses corresponding to the signal after being amplified are been obtained. Average roughness Ra value surface of change the measured distance of the signal average rate of outline from reference point determined from the..

Furthermore, fluorine ℓ / 100 milliliter YSZ electrode substrates 100 milliliter and dissipation installed inside a desalting tub 5 to acid solution including sulfuric acid in the adaptation etching immersed minutes. Furthermore, said electrode substrates, such as described in the embodiment 2 and refitted again plating it was determined that their average roughness. Table 1 the etch before co-etched substrates and electrode electrode substrate in which a deposited surface roughness for exhibits one selected from a group of spline.

Figure 6 shows a also etched yttria stabilized zirconia electrode substrate on co-deposited coating of nickel and YSZ Image is magnified, 5060 is a scanning electron micrographs. A Cambridge Stereoscan 90 microscopically said SEM are obtained. Said YSZ/nickel etching surface the micrographs co-deposited coating is eminently been impact on the conditions of the show. Surface roughness is increased as well as touches of a user's fingers for, co-deposited been using the light the light source provides porous electrode substrate in which a. Surface roughness and porous increased surface area for a larger anode performance improved 2000.

Said co-deposited of EDX spectrum a complex also been have shown that deposition is obtained. 7 also representative of a spectrum are shown. Nickel coating a binder and co-deposited YSZ a transition corresponding to particulate material revealed that intensity peaks results. SEM with an analysis EDX spectrum a combination result, said uniformly coating face is disposed to face the emitting electrode substrate been has been confirmed.

Fisherscope XDL-Z X-ray fluorescent device said co-deposited using XRF analysis of electrode substrate in which a thickness of a coating 10 to 13 micro m is position of the been are obtained.

In the embodiment 4 : manufacturing cathode on insulating substrate

Alumina electrode substrate (a communication network and downloads one: Napier University) a pretreatment as described above in the embodiment 2, activated (is facilitated by making the processes of) corresponding advertisement based on the shown list, added catalyst. Furthermore, is activated said pre-processing of a electrode substrate in which a catalyzed and removing them from the solution at room temperature was then being washed with deionized water.

Furthermore, plating dropper Slotonip 2010 (Schloetter Company Limited) nominal particle size 5 micro m ℓ / 50g of lanthanum strontium manganate powder (a communication network and downloads one: Unitec Ceramics) applying a same mechanically agitated suspended when the electroless nickel plating solutions manufacturing processes and the cost of production. Furthermore, said solution using stirrer hot plate was heated to a temperature of 89 °C. Furthermore, and the catalyst activated said metallized dielectric with electrode substrate said immersing plating solution was 30 minutes. After removing the plating from an electrolytic cell, said coated cathode substrate which washes the-useless error deionized water, then propane-2-ol (class reagent for analysis) both at room temperature performed for all the then being washed with but. Furthermore, nickel co-deposited strontium oxide and lanthanide electrode substrate in which a to a dried in the air.

In the embodiment in Figure 8 shows a a are also on a substrate electrode fabricated co-deposited nickel and lanthanide strontium manganate coating is a scanning electron micrographs. Also through electric communication of the transistor of Figure 8 and 2, said electrode substrate across a surface is evenly nickel and lanthanide been strontium manganate co-deposition occurs can be viewed.

Also 8 in a region represented by "spectrum 2" EDX spectrum a is shown in 9. Nickel coating a binder and co-deposited lanthanides strontium manganate a transition corresponding to particulate material revealed that intensity peaks results. SEM with an analysis EDX spectrum a combination result, said electrode substrate is uniformly coating the output insurance document is corresponding advertisement based on the shown list, thereby been obtained cathode suitable SOFC.

The unpracticed people the party the field to do to a appended claim the present invention is without deviates from category of several various method may be performed will understand. For example, the present invention refers to selective disclosure herein or desirable properties. comprising a combination of at least one.