CN101057362A

CN101057362A - Use of an electrochemical cell such as a fuel cell

Info

Publication number: CN101057362A
Application number: CNA2005800389945A
Authority: CN
Inventors: D·J·海格特; S·伯恩; S·D·斯考特罗夫特
Original assignee: ITM Power Research Ltd
Current assignee: ITM Power Research Ltd
Priority date: 2004-09-21
Filing date: 2005-09-21
Publication date: 2007-10-17
Also published as: ZA200702339B; GB0420961D0

Abstract

A method of performing an electrochemical reaction in an electrochemical cell comprises electrodes separated by a membrane capable of taking up an electrolyte, the method comprises introducing into the cell a fuel or other oxidisable component and an electrolyte, and oxidising the fuel in the presence of an acid or alkali. Alternatively or in addition, usage of fuel may be monitored by including a reactant that is capable of undergoing or imparting a change in visual appearance on oxidation or reduction; and monitoring any change in visual appearance.

Description

A kind of electrochemical cell is the purposes of fuel cell for example

Technical field

The present invention relates to a kind of method of carrying out electrochemical reaction.

Background technology

WO03/23890 discloses ion exchange material can be based on the hydrophilic polymer manufacturing, and described hydrophilic polymer promptly itself can absorb and transmit the polymer of water by its molecular structure.This material and hydrogen-air fuel cell relation are particularly close, because product water can be reallocated, can avoid the part immersion (flooding) or the drying of film thus.Substantially there are three kinds of modes can make water wetted material have ionic conductivity.

First kind of mode is for forming the ion activity center by copolymerization in the ion activity monomer solution; This method is recorded in WO03/23890.Owing to formed reinforcing yin essence ion or strong cation part in the polymer that generates, made it can serve as anion exchange (AE) or cation exchange (CE) material respectively.

The second way is for example carried out grafting by the existing polymer molecule of sulfonation (for example Nafion) or to existing polymer film for adding the ion activity center.

The third mode is for to carry out aquation to water wetted material in acid or alkali lye.Water wetted material for example HEMA (methacrylic acid 2-hydroxyl ethyl ester) and MMA-VP (methyl methacrylate-vinylpyrrolidone) itself does not have electrical property, if carry out hydration in deionization distillation (DD) water, is good resistance.If but it were carried out hydration in acid or aqueous slkali, then could become good conductor.A limitation of this method is that conductibility descends along with electrolyte solution flush away (washout), and material finally can become electric inertia.This flush away especially is a problem in electrolysis tank and in hydrogen-air fuel cell, exists because reactants water is a large amount of usually in electrolysis tank, then generates water in hydrogen-air fuel cell.

Sodium borohydride fuel cell also is known.For example sodium hydrate aqueous solution is stable with aqueous slkali usually for sodium borohydride fuel cell.

US58804329 and US5948558 have put down in writing boron hydrogen ion (BH ₄ ^-) produce the fuel cell of electric current in anodic oxidation.This fuel is solution form, for example sodium borohydride solution.The battery of similar type also has open in WO-A-02/00950 and WO-A-02/052664.

There is the dual mode can be with the oxidation of boron hydrogen ion.When using acid condition, think that the oxidation of boron hydrogen ion generates hydrogen, hydrogen then is consumed (being referred to as " d-type " method among the application).Under alkali condition, think that the boron hydrogen ion is directly consumed, produce hydrogen (being referred to as " D-type " method among the application) in the middle of promptly not having.D-type mode (about 1.2V) is lower than the voltage that D-type mode (about 1.6V) produces, because the conversion process of hydrogen has consumed portion of energy.

Although above-mentioned publication has been mentioned d-type and D-type battery, almost do not have evidence to show and produce the effective battery that uses any mechanism.In fact, the actual motion that seems also to have no talent is crossed a kind of D-type battery.

Similar problem also ran in the alcohol-group fuel battery; So far still carrying out unremitting effort to obtain a kind of system that can under the power density of theoretical maximum voltage or acceptable level, move near it.

The amount of fuel is along with this battery is converted into chemical energy electric energy and descends relevant in another problem and the battery.This fuel consumption process can last till always that performance descends fast and battery is finally out of service.At this moment, battery refuelling again.The not low warning in advance of fuel reserves about when.

Summary of the invention

One aspect of the present invention solves and makes water wetted material have the limitation of conductive the third mode, and it is based on the recognition, and can comprise dopant material in fuel (or other oxidizable components) or oxidant, and this material can be acidity or alkalescence; In fact, found in a kind of liquid (for example oxidant), to add acid material and while adding basic matterial in another kind of liquid (for example fuel).Similarly, the conductibility of weak ionic hydrophilic film also can improve by using such fuel.

According to an aspect of the present invention, a kind of method of in electrochemical cell, carrying out electrochemical reaction, described battery comprises the electrode that is separated by the hydrophilic membrane of hanging down ionic conductivity, described method comprises to be introduced a kind of aqueous solution in this battery, this aqueous solution contains fuel and/or oxidant, the two one of or the both can comprise electrolyte; And in the presence of this electrolyte this fuel of oxidation.

Another aspect of the present invention is based on finds that the disclosed AE membrane material of WO03/23890 is a solution of above-mentioned problem about the boron hydride battery.Particularly, found when this material is used in combination with alkali condition, can promote D-type boride oxidation mechanism.

Aspect this, fuel cell comprises the electrode that is separated by anion-exchange membrane, and wherein this film comprises the hydrophilic polymer that contains the reinforcing yin essence ionic group, and wherein fuel is boron hydride solution or alcoholic solution.Particularly, voltage can produce by oxygenated fuel in the fuel cell that contains the electrode that is separated by anion-exchange membrane, and wherein this film comprises the hydrophilic polymer that contains the reinforcing yin essence ionic group, and wherein fuel is boron hydride solution or alcohol.

The present invention also is based on the recognition, and promptly when the needs refuelling or when filling up, the reactant of available fuel or interpolation is indicated by change color.For example, change color can take place in fuel or oxidant when reaction.

Therefore, a further aspect of the invention is a kind of method of carrying out electrochemical reaction in electrochemical cell, described electrochemical cell comprises the electrode that is separated by amberplex, described method comprises that employing when working as oxidation or reduction the reactant that visual appearance changes can take place or present, and any variation of visual appearance is monitored.

Another aspect of the present invention is a kind of electrochemical cell that comprises the electrode that is separated by amberplex, wherein this battery comprises a kind of liquid, described liquid comprises when oxidation or reduction, and the reactant that visual appearance changes can take place or present, and wherein said battery comprises watch window, can be observed the visual appearance of this liquid by it.

These aspects of the present invention provide a kind of simple visual indicators of battery life, and for concrete fuel cell, the amount of may command fuel and oxidant is so that the change color at least a solution is enough to provide very fast needs reinforced indication.

Specific embodiments

Water wetted material can be the ion inertia, and promptly itself does not have electrical property.In this case, ion activity is given this material by electrolyte.Perhaps, this water wetted material can have weak ion activity, comprises anion or cationic species in its structure.Wherein, electrolyte aqueous solution has improved the ion activity of this water wetted material.Weak active material is generally such material, when it carries out hydration in deionized-distilled water, the ionic conductance that demonstrates be lower than industry standard material for example Nafion 117 conductivity 60%, generally be lower than 50%.

Perhaps, disclosed as PCT/GB2005/002356, film can be a kind of composite construction that contains neutral component and/or AE component and/or CE component.Wherein a kind of ion activity material randomly is intrinsic strong ion-conducting material.

Water wetted material can obtain by using any suitable method well known in the prior art.For example, can form weak ion activity material according to the described method of WO03/23890, the content of this patent application is included this specification in by the mode of quoting as proof.This material is preferably hydrophilic polymer, for example can be by the hydrophilic polymer of monomer polymerization or copolymerization acquisition, described monomer is methyl methacrylate, acrylonitrile, N-vinyl-2-Pyrrolidone, [2-(acryloyl-oxy) ethyl] trimethyl ammonium chloride or [3-(methacrylamido) propyl group] trimethyl ammonium chloride for example, and polymer is preferably crosslinked.For example, the AE material is preferably hydrophilic and copolymer hydrophobic monomer, and preferred monomer comprises acrylonitrile, l-vinyl-2-pyrrolidone, hydroxyethyl methacrylate and methyl methacrylate.Preferably, the reinforcing yin essence ionic group is [3-(methacrylamido) propyl group] trimethyl ammonium chloride, [2-(acryloyl-oxy) ethyl] trimethyl ammonium chloride, NaOH or potassium hydroxide, perhaps derives from above-mentioned substance.Especially preferred AE material is a disclosed material in this specification table 1.

For example, solution can comprise reactant for example liquid fuel or oxidant.Suitable fuel comprises alcohol (for example methyl alcohol and ethanol) and boron hydride (for example sodium borohydride).An example of liquid oxidizer is a hydrogen peroxide, and another example is KMnO ₄

Fuel or other oxidable component when using as electrolysis tank (for example battery be) can be gaseous state, but are preferably liquid state, and may to need system be incompressible.The existence of water makes and fuel and/or oxidant can be transported in the hydrophilic membrane.

Electrolyte can be acid or alkaline.Suitable electrolytical example comprises toluenesulfonic acid (TSA), vinyl sulfonic acid, acrylamido-(2-methyl) propane sulfonic acid (AMPSA), NaOH or potassium hydroxide.When reactant was alcohol or boron hydride, preferred electrolyte was an alkali, for example NaOH or potassium hydroxide.Required electrolytical concentration is significantly for those of ordinary skills, and is controllable, for example by the input of control in battery.

Should be realized that when fuel was boron hydride solution, according to the condition of using, battery can be by d-type or the operation of D-type mechanism.D-type mechanism can be simply by using platinum catalyst to realize at anode.As for D-type system, preferably use Au catalyst and boron hydride solution to be aqueous slkali, preferably comprise potassium hydroxide or NaOH.

When fuel is pure fuel, should alcohol be methyl alcohol or ethanol preferably then, preferred alcohols is in the alkaline solution.Suitable fuel can be stablized by the existence of acid or alkali.For example, fuel can a side of film with alkali stable and/or oxidant can be stable with acid at the opposite side of film.But more generally, the liquid of the either side of film or both sides can be acidity or alkalescence.

If one of electrolyte and fuel are charged, the behavior the when behavior of battery contains simple acid or alkali film to it is similar.If the both is charged, then can produce compound effect.

As mentioned above, an aspect of of the present present invention relates to the change of color.The reactant that change color can take place can be a liquid fuel.Alcohol fuel is methyl alcohol or ethanol water oxidized back formation carbon dioxide and other materials for example.Along with this fuel oxidation, it is muddy that the solution of pure and mild calcium hydroxide can become, because the carbon dioxide and the calcium hydroxide reaction that generate have formed calcium carbonate.Thereby in this case, change in color is a kind of variation of cloudiness.

As the substituting or replenishing of the above scheme, reactant can be the oxidant that generally exists with liquid state.The aqueous slkali of potassium permanganate is when oxidation, along with variation from the purple to the green can take place for the formation of mangaic acid radical ion.If this solution is acid, then can generate colourless solution.Should be realized that reactant can the altered self color or (in situ) causes change in color on the spot.

Fuel cell can be the form of or one group of membrane-electrode assembly (MEA).The method of producing this equipment is disclosed in WO-A-03/23890.

The present invention of following examples exemplary illustration.

Material

Have in this abbreviation of using and material:

Acrylonitrile (AN)

L-vinyl-2-pyrrolidone (VP)

Hydroxyethyl methacrylate (HEMA)

Methyl methacrylate (MMA)

[3-(methacrylamido) propyl group] trimethyl ammonium chloride (BA)

[2-(acryloyl-oxy) ethyl] trimethyl ammonium chloride (BN)

Acrylic acid dimethylamino ethyl ester (BE)

Ethylene benzyl trimethyl ammonium chloride (BV)

NaOH (BS)

Potassium hydroxide (BP)

Hplc grade water (R)

Allyl methacrylate (X)

Azodiisobutyronitrile (Z)

12 kinds of AE membrane materials have been prepared, the basic moiety that has multiple permanent polymerization in the material.Described AE material composed as follows:

Table 1

Sample number	VP	AN	HEMA	MMA	BV	BE	BA	BN	X	R	Z
Sample number	VP	AN	HEMA	MMA	BV	BE	BA	BN	X	R	Z	1g	70.67	70.67			28.39	1.89	28.39
1t	69.76	69.76				27.90			1.86	27.90	2.80	1g	70.67	70.67			28.39	1.89	28.39
1t	69.76	69.76				27.90			1.86	27.90	2.80	2g	70.67		70.67	28.39		1.89	28.39
2t	69.76		69.76		27.90				1.86	27.90	2.80	2g	70.67		70.67	28.39		1.89	28.39

3g	70.67	70.67		28.39			1.89	28.39
3g	70.67	70.67		28.39			1.89	28.39	3t	69.76	69.76		27.90			1.86	27.90	2.80
4g	70.67	70.67			56.78		1.89		3t	69.76	69.76		27.90			1.86	27.90	2.80
4g	70.67	70.67			56.78		1.89		4t	69.76	69.76			55.80		1.86		2.80
5g	70.67		70.67			34.07	1.89	22.7	4t	69.76	69.76			55.80		1.86		2.80
5g	70.67		70.67			34.07	1.89	22.7	5t	69.76		69.76			34.86	1.86	20.92	2.80
6g	70.67		70.67	28.39			1.89	28.39	5t	69.76		69.76			34.86	1.86	20.92	2.80
6g	70.67		70.67	28.39			1.89	28.39	6t	69.67		69.67	27.90			1.86	27.90	2.80

In the table 1, suffix " g " and " t " represent respectively to be cured by radiation gamma with by heat treatment.All units are gram.

Embodiment 1:d-type borohydride fuel battery

The material sample 5g of hydration in the potassium hydroxide solution of 2M is as the film of borohydride fuel battery.This battery has following characteristic and component:

Active area 3.142cm ²

The anode/cathode catalyst Pt is black, 5mg/cm ²Nafion solution-treated (Lynntech)

Electrode 0.35mm ELAT graphitized charcoal cloth

Current-collector 0.85mm stainless (steel) wire

By being dissolved in the 100g water, the 1g sodium borohydride prepares fuel solution.After 15 minutes, can see that little bubble is arranged on mixer wall, suppose that this slow conversion by hydrogen produces.

The anode chamber that then will about 10ml sodium borohydride solution directly introduces fuel cell.Oxygen is infeeded cathode chamber.Fuel and oxidant do not circulate.Open circuit voltage is very fast soaring to 0.9495V.Earlier the different resistance of this battery by certain limit are carried out a series of short-circuit test, test then polarizes.The result is shown in Fig. 1 and table 2.

Table 2

Resistance (Ω)	Maximum current density (mA/cm ²)	Minimum voltage (V)	Power density (mW/cm ²)
Resistance (Ω)	Maximum current density (mA/cm ²)	Minimum voltage (V)	Power density (mW/cm ²)	0.5	207.2	0.4637	96.1
0.3	241.0	0.4085	98.4	0.5	207.2	0.4637	96.1
0.3	241.0	0.4085	98.4	0(a)	314.4	0.2731	85.9
0(b)	321.0	0.2509	80.5	0(a)	314.4	0.2731	85.9
0(b)	321.0	0.2509	80.5	0 (c) is long	320.1	0.2477	79.3

This battery demonstrates than the anticipation more performance.In polarization process at 53.8mA/cm ²Record maximum power density 36.6mW/cm ², at 241mA/cm ²Record instantaneous maximum power density 98.4mW/cm ²The voltage curve of polarization curve demonstrates three characteristic areas, often is called (i) region of activation (kinetic region), (ii) resistance area (resistive region) and (iii) mass transfer limit district.Special concern be the mass transfer zone, this zone has the feature that voltage diminishes gradually when higher current density.

Also carry out the short-circuit test of another one series, be used for being disclosed in the more susceptible condition of current density instantaneous power response when higher.Suppose that suchlike quick short-circuit test only utilizes the fuel that has been present in the film surface, and do not rely on other fuel through current-collector and electrode structure.

The results are shown in Fig. 2.Each data point all from independently test fast, makes the open circuit voltage 0.9V that rises before carrying out next test.The value that epicycle has been tested the back open circuit voltage is 0.9793V.

Can see in the test process that the minute bubbles that are assumed to hydrogen slowly form in the anode chamber.Although this shows directly sodium borohydride solution is introduced, fuel cell is actually and relies on hydrogen operation that anode catalyst produces.

Make then and in the sodium hydroxide solution of 2M, carry out pretreated material sample 5g and be used for replacing existing film in the battery.This has demonstrated positive-effect to electric current and power density.When infeeding fuel in the battery for the first time, open circuit voltage rises to 0.921V very soon.Carried out a series of short-circuit test to estimate the instantaneous power response.The maximum current that obtains from battery surpasses 1.5A, and this value is equivalent to 478.9mA/cm ²At 307.4mA/cm ²The time obtain maximum instantaneous power density 136.7mW/cm ²

Embodiment 2:D-type borohydride fuel battery

Used the similar fuel cell of a kind of and embodiment 1, it contains a kind of golden net anode catalyst of following specification:

Purity 99.99%

Silk footpath 0.060mm

Aperture size 0.25mm

Effective screening area 65%

4g and 6g membrane material are tested, and fuel used is the sodium borohydride of 10 weight % in the 2M sodium hydroxide solution.

The maximum open circuit voltage (OCV) that is obtained with the 4g material is 1.5182.The OCV that uses the 6g material to be obtained is 1.5296.These results show because the alkalescence of hydrophilic film material has stoped and has been converted into " effusion " hydrogen.This environment combined with Au catalyst is enough to make the sodium borohydride direct oxidation, promptly by D-type mechanism.

Embodiment 3: alcohol fuel battery

The material of embodiment 1 when having designed a kind of fuel cell and being fuel with methyl alcohol and ethanol to estimate.This battery has following characteristics:

Active area 3.142cm ²

Anode catalyst Pt:Ru is black, 5mg/cm ²Nafion solution-treated (Lynntech)

Cathod catalyst Pt is black, 5mg/cm ²Nafion solution-treated (Lynntech)

Electrode ELAT graphitized charcoal cloth, nominal thickness 0.35mm

The current-collector stainless (steel) wire, nominal thickness 0.85mm

The various fuel of packing into successively in the anode of battery comprise hydrogen.This can link to each other with outlet with the import of anode by lacking the siloxanes pipe, directly liquid fuel is injected by a syringe and realizes.When air was oxidant, cathode chamber kept opening wide to atmosphere.When using hydrogen and oxygen, it provides by a small-sized electrolysis tank to be slightly higher than atmospheric pressure.Fuel and oxidant all do not circulate.All tests are all at room temperature carried out.

Write down the polarization curve of each system, under possible situation, short-circuit the battery so that can measure the maximum instantaneous current density.The results are shown in Fig. 3 and 4 and table 3.

Table 3

Fuel	Oxidant	Maximum OCV (V)	Maximum power density (mW/cm ²)	Current density (mA/cm during maximum power ²)	Maximum sustainable current density (mA/cm ²)	Maximum instantaneous current density (mA/cm ²)
Fuel	Oxidant	Maximum OCV (V)	Maximum power density (mW/cm ²)	Current density (mA/cm during maximum power ²)	Maximum sustainable current density (mA/cm ²)	Maximum instantaneous current density (mA/cm ²)	Hydrogen	Oxygen	0.86	0.18	0.76	1.69	3.72
2M methyl alcohol	Oxygen	0.77	0.13	0.31	1.08	5.70	Hydrogen	Oxygen	0.86	0.18	0.76	1.69	3.72
2M methyl alcohol	Oxygen	0.77	0.13	0.31	1.08	5.70	2M methyl alcohol	Air	0.49	0.04	0.13	0.29	-
4M methyl alcohol	Oxygen	0.705	0.10	0.32	0.41	2.42	2M methyl alcohol	Air	0.49	0.04	0.13	0.29	-
4M methyl alcohol	Oxygen	0.705	0.10	0.32	0.41	2.42	4M methyl alcohol 4M KOH	Oxygen	1.175	0.72	1.85	5.48	72.93

Ce Shi battery is for all successful operations of all fuel obviously.Add potassium hydroxide and cause performance to obtain maximum the raising in fuel, power density is brought up to 7 times.Open circuit voltage is 1.175V, and this value is very high, approaches the obtainable theoretical maximum 1.21V of methanol fuel.

Also use 2g, 4g and 5g material to move direct methanol feeding (DMF) battery, and use 4g and 5g material to move direct ethanol charging (DEF) battery.In the dual mode, by for example the NaOH of 2M or potassium hydroxide solution carry out preliminary treatment to the AE sample and all obtained significant effect with aqueous slkali.

Figure 5 shows that when using methyl alcohol and ethanol-based fuel successively, used the result that fuel cell obtained of the 4g AE sample of hydration in the NaOH of 2M.The methanol feeding battery is at 52mA/cm ²The time power density be 12mW/cm ², ethanol charging battery is at 54mA/cm ²The time power density be 17mW/cm ²

Further test the ethanol charging battery that uses the 4g AE that handles through multiple mode, produced result as shown in table 4.

Table 4

Sample	Fuel	Oxidant	Maximum OCV	Maximum current density polarization (mA/cm ²)	Instantaneous (the mA/cm of maximum current density ²)	Maximum power density polarization (mW/cm ²)	Instantaneous (the mW/cm of maximum power density ²)
Sample	Fuel	Oxidant	Maximum OCV	Maximum current density polarization (mA/cm ²)	Instantaneous (the mA/cm of maximum current density ²)	Maximum power density polarization (mW/cm ²)	Instantaneous (the mW/cm of maximum power density ²)	i4ghR	2M ethanol	Air	0.6295	2.36	16.01	0.45	2.31
i4ghR	2M ethanol	Oxygen	0.6388	2.77	15.37	0.47	2.37	i4ghR	2M ethanol	Air	0.6295	2.36	16.01	0.45	2.31
i4ghR	2M ethanol	Oxygen	0.6388	2.77	15.37	0.47	2.37	i4ghR	2M ethanol, 2M NaOH	Oxygen	0.7230	8.72	52.26	1.48	6.96
i4gh2Na	2M ethanol, 2M NaOH	Oxygen	0.8808	92.65	322.50	15.15	63.95	i4ghR	2M ethanol, 2M NaOH	Oxygen	0.7230	8.72	52.26	1.48	6.96

Other material

Four kinds of hydrophilic film materials (A is to D) have been prepared according to the described method of WO03/23890.The composition of every kind of material is shown in the following table 5.Materials A and B are weak ion activity AE material owing to the concentration of the trimethyl ammonium chloride solution that uses is low in preparation process.Material C and D are the ion inertia.

Table 5

Component	A	B	C	D
Component	A	B	C	D	L-vinyl-2-pyrrolidone	70.67	70.67	0.00	100.00
Acrylonitrile	0.00	0.00	0.00	100.00	L-vinyl-2-pyrrolidone	70.67	70.67	0.00	100.00
Acrylonitrile	0.00	0.00	0.00	100.00	Hydroxyethyl methacrylate	70.67	70.67	100.00	0.00
Methyl methacrylate	0.00	0.00	0.00	0.00	Hydroxyethyl methacrylate	70.67	70.67	100.00	0.00

[2-(acryloyl-oxy) ethyl] trimethyl ammonium chloride (80%)	0.00	35.38	0.00
[2-(acryloyl-oxy) ethyl] trimethyl ammonium chloride (80%)	0.00	35.38	0.00	[3-(methacrylamido) propyl group] trimethyl ammonium chloride (50%)	56.60	0.00	0.00	0.00
Allyl methacrylate	1.89	1.89	2.00		56.60	0.00	0.00	0.00
Allyl methacrylate	1.89	1.89	2.00	HPLC water	0.00	21.22	10.00	0.00

Embodiment 4

A kind of ethanol operation that contains the fuel cell of membrane material A with 2M.Then this battery moves with the 2M ethanol of doping 2M NaOH again.As shown in table 6, the performance of battery has improved behind the interpolation 2M NaOH in fuel.

Table 6

Fuel	Oxidant	Open circuit voltage (V)	Maximum current density polarization (mA/cm ²)	Instantaneous (the mA/cm of maximum current density ²)	Maximum power density polarization (mW/cm ²)	Instantaneous (the mW/cm of maximum power density ²)
Fuel	Oxidant	Open circuit voltage (V)	Maximum current density polarization (mA/cm ²)	Instantaneous (the mA/cm of maximum current density ²)	Maximum power density polarization (mW/cm ²)	Instantaneous (the mW/cm of maximum power density ²)	2M ethanol	Oxygen	0.6388	2.77	15.37	0.47	2.37
2M ethanol, 2M NaOH	Oxygen	0.7230	8.27	52.26	1.48	6.96	2M ethanol	Oxygen	0.6388	2.77	15.37	0.47	2.37

Embodiment 5

A kind of fuel cell that contains membrane material B uses three kinds of different operating fuels: the 4M methyl alcohol of the methyl alcohol of hydrogen, 4M and doping 4M KOH.The oxidant that all situations uses down is oxygen.Table 7 clearly shows and add KOH has the front to performance influence in methanol fuel.

Table 7

Fuel	Oxidant	Open circuit voltage (V)	Maximum current density polarization (mA/cm ²)	Instantaneous (the mA/cm of maximum current density ²)	Maximum power density polarization (mW/cm ²)
Fuel	Oxidant	Open circuit voltage (V)	Maximum current density polarization (mA/cm ²)	Instantaneous (the mA/cm of maximum current density ²)	Maximum power density polarization (mW/cm ²)	Hydrogen	Oxygen	0.860	1.69	3.72	0.18
4M methyl alcohol	Oxygen	0.705	0.41	2.24	0.1	Hydrogen	Oxygen	0.860	1.69	3.72	0.18
4M methyl alcohol	Oxygen	0.705	0.41	2.24	0.1	4M methyl alcohol, 4M KOH	Oxygen	1.175	5.48	72.93	0.7

Embodiment 6

A kind of methanol fuel cell that contains the 4M of membrane material C produces 0.0006875mW/cm ²Peak power density, promptly invalid substantially.Obtained similar result during materials used D.Add NaOH in fuel performance has been produced remarkable influence, the peak power density of generation surpasses 1mW/cm ², peak current density is 9.8mA/cm ²And instantaneous peak current density is 30mA/cm ²

Embodiment 7

The liquor potassic permanganate (oxidant) of 1 weight % of the sodium borohydride solution (fuel) of 1 weight % of doping 2M potassium hydroxide and doping 2M potassium hydroxide is supplied with the fuel cell that contains anion SPE.

Polarization data is shown in Fig. 6.This battery can obtain the OCV of 1.5V.The color of oxidizing agent solution is a purple, but begins to become green at last, and showing needs refuelling very soon or fill it up with.This change in color is because high manganese ion reduces formed mangaic acid radical ion.

Embodiment 8

The fuel cell of cation SPE is with liquor potassic permanganate (oxidant) operation of 1 weight % of the sodium borohydride solution (fuel) of 1 weight % and doping 0.1M sulfuric acid.

Polarization data is shown in Fig. 7.This battery obtains the OCV of 2V.The color of this oxidizing agent solution becomes colourless from purple, the warning in advance that needs refuelling or fill it up with is provided.

Embodiment 9

Contain of hydrogenperoxide steam generator (oxidant) operation of the fuel cell of anion SPE with the 2M methanol solution (fuel) and the 1 weight % of doped with hydrogen calcium oxide solution.

Fuel provides the warning in advance that needs refuelling or fill it up with from the limpid muddiness that becomes.The variation of turbidity is that wherein carbon dioxide is a kind of product of methanol oxidation because calcium hydroxide and carbon dioxide reaction have formed the cause of calcium carbonate.

Claims

1. method of carrying out electrochemical reaction in electrochemical cell, described electrochemical cell comprise that by the electrode that can receive electrolytical film to separate this method comprises to be introduced oxidable component and electrolyte in the battery, and in the presence of acid or alkali with oxidized.

2. according to the process of claim 1 wherein that this film is the ion inertia.

3. according to the process of claim 1 wherein that this film has relatively low conductibility when not having the component of this introducing.

4. according to the method for the arbitrary claim in front, wherein the ionic conductivity of this film be lower than Nafion 117 ionic conductivity 60%.

5. according to the method for the arbitrary claim in front, wherein oxidation step comprises the introducing liquid oxidizer.

6. according to the method for the arbitrary claim in front, wherein one of this oxidable component and this oxidant comprise acid and another comprises alkali.

7. according to the method for the arbitrary claim in front, wherein this oxidable component is pure fuel or borohydride fuel.

8. according to the method for claim 7, wherein this fuel is methyl alcohol, ethanol or sodium borohydride.

9. according to the method for the arbitrary claim in front, wherein this electrolyte is alkaline.

10. according to the method for claim 9, wherein this electrolyte is NaOH or potassium hydroxide.

11. according to the method for the arbitrary claim in front, wherein this battery is the form of or one group of membrane-electrode assembly (MEA).

12. according to the method for the arbitrary claim in front, wherein this film can be the composite membrane of any combining form of neutral material and AE material and CE material.

13. according to the method for the arbitrary claim in front, wherein this anode comprises catalyst.

14. according to the method for claim 13, this catalyst package platiniferous wherein.

15. according to the method for claim 13, wherein this catalyst comprises gold.

16. a method of carrying out electrochemical reaction in electrochemical cell, described electrochemical cell comprises the electrode that is separated by amberplex, and this method comprises that employing when oxidation or reduction the reactant that visual appearance changes can take place or present; And monitor the variation of any visual appearance.

17. according to the method for claim 16, wherein this reactant is fuel or is present in the fuel.

18. according to the method for claim 17, wherein this fuel is alcohol.

19. according to the method for claim 18, wherein this alcohol is present in the aqueous solution that contains calcium hydroxide.

20., should alcohol be methyl alcohol or ethanol wherein according to the method for claim 18 or 19.

21. according to the method for arbitrary claim in the claim 16 to 20, wherein this reactant is an oxidant.

22. according to the method for claim 21, wherein this oxidant is a potassium permanganate solution.

23. according to the method for arbitrary claim in the claim 16 to 22, wherein this battery is the form of or one group of membrane-electrode assembly (MEA).

24. electrochemical cell that comprises the electrode that separates by amberplex, wherein this battery comprises a kind of liquid, this liquid comprises when oxidation or reduction, and the reactant that visual appearance changes can take place or present, and wherein this battery comprises watch window, can be observed the visual appearance of this liquid by it.

25. according to the battery of claim 24, it defines as arbitrary claim in the claim 17 to 23.