水燃料電池
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1. 水燃料電池
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“中興水燃料電池”是當今中興的一重要發明,它不像國內所謂“空氣電池”或乾電池那樣只一次性使用還要消耗大量的金屬,也不像國內外大肆宣揚的“燃料電池”那樣必須一刻不停 ...www.zxkjw.com/srldc.html - 7k - 頁庫存檔 - 類似網頁
2. 燃料電池- 維基百科,自由的百科全書
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燃料電池(Fuel cell),是一種使用燃料進行化學反應產生電力的裝置,最早於1839 ... 最常見是以氫氧為燃料的質子交換膜燃料電池,由於燃料價格平宜,加上對人體無化學 ...zh.wikipedia.org/wiki/燃料电池 - 37k - 頁庫存檔 - 類似網頁
3. 科幻小說?三星水燃料電池2010年將上市-中關村在線
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2008年4月22日 ... 來自韓國的三星電子旗下的Electro-Mechanics近日成功研製了一種使用水作為“燃料”的微型.mobile.zol.com.cn/89/897419.html - 83k - 頁庫存檔 - 類似網頁
4. 解密日本“水燃料”汽車1公升水可跑1小時_科技頻道_新華網
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2008年6月17日 ... Genepax解釋說,他們利用一種名為“水能量系統(WES)”新燃料電池系統 ... 此系統將外來的水和空氣分別供給此燃料電池和空氣電極,從而產生出電力。 ...news.xinhuanet.com/tech/2008-06/17/content_8383543.htm - 29k - 頁庫存檔 - 類似網頁
5. 台灣燃料電池資訊網
2008年4月9日 ... 合盈光電總經理許玄岳指出,水燃料電池參展內容包括:加水就會動的玩具、 ... 恆電能源開發首席顧問吳溢隆表示,「水燃料電池(Aqua fuel cell)」是 ...www.tfci.org.tw/news/newsDetail.asp?id=622 - 12k - 頁庫存檔 - 類似網頁
6. 電池升級三星水燃料電池手機即將面世- 新浪網- Mobile
圖為:三星水燃料電池手機. 據報道稱,三星目前正在研發一個微型燃料電池,盡管還處于保密階段,但我們已經得知該原理是通過金屬與水發生的化學反應來產生氫氣,然後 ...mobile.sina.com.hk/cgi-bin/nw/show.cgi/3/4/1/683940/1.html - 35k - 頁庫存檔 - 類似網頁
7. 綠色環保時代 三星水燃料電池2010年將上市--產品-- CCTIME飛象網
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2008年4月23日 ... 三星,水燃料,來自韓國的三星電子旗下的Electro-Mechanics近日成功研製了一種使用水作為“燃料”的微型燃料電池和氫氣發電機,引起了業內不小的轟動。www.cctime.com/html/2008-4-23/2008423847091145.htm - 41k - 頁庫存檔 - 類似網頁
8. 水燃料電池車子加水就會走- 產業經濟局勢- 聚財網理財論壇
22 篇文章 - 12 位作者
水燃料電池>>通過把水與一種鋁鎵合金的珠狀粒子相混合,產生氫來取代對汽油的方法. .... 台灣水燃料電池(Aqua fuel cell)」是整合量子學、奈米材料及燃料電池技術, ...www.wearn.com/bbs/topic.asp?topic_id=125739&forum_id=110&cat_id=19 - 118k - 頁庫存檔 - 類似網頁
9. 綠色環保三星水燃料電池將2010年上市- 電動自行車,電動腳踏車等及零 ...
Oh Yong-soo表示,如果不出意外的話,使用“水燃料”發電的微型燃料電池最早在2010年就可以正式上市銷售、裝備手機產品了,屆時,相信三星公司一定會引起一場手機電池 ...tw.myblog.yahoo.com/jw!YAiCzRCUCUS1qikpWKMeLQ--/article?mid=30&sc=1 - 28k - 頁庫存檔 - 類似網頁
10. Only Perception: 新燃料電池系統水與空氣即可產生電力
於此同時,這個300W 的燃料電池系統是一套主動系統,那以一具幫浦提供水與空氣。在示範中,Genepax 以一個由此系統充電的鉛酸電池,提供電力給電視與照明設備。 ...only-perception.blogspot.com/2008/07/blog-post_8966.html - 119k - 頁庫存檔 - 類似網頁
相關搜尋:
燃料電池
燃料電池原理
燃料電池車
燃料電池公司
燃料電池應用
生物燃料電池
燃料電池種類
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http://tw.myblog.yahoo.com/jw!YAiCzRCUCUS1qikpWKMeLQ--/article?mid=30&sc=1
綠色環保 三星水燃料電池將2010年上市
http://tw.myblog.yahoo.com/jw!YAiCzRCUCUS1qikpWKMeLQ--/article?mid=30&sc=1
綠色環保 三星水燃料電池將2010年上市
2008-04-21 15:31:25
轉寄給朋友
列印
文/姚碩
來自韓國的三星電子旗下的Electro-Mechanics近日成功研制了一種使用水作為“燃料”的微型燃料電池和氫氣發電機,引起了業內不小的轟動。三星Electro-Mechanics(電流體力學)研究中心的副主任Oh Yong-soo聲稱,使用該裝置可以使手機電池中的特殊金屬和水產生化學反應,從而釋放出發電所用的氫氣。釋放的氫氣在發電機內同空氣中的氧氣發生燃燒,產生用于推動發電機運轉所需的能量。
目前,大多數燃料電池都是使用甲醇作為產生氫氣的燃料,而三星公司的新技術將允許燃料電池直接使用更加安全、方便的水作為產生氫氣的添加劑。
三星“水燃料”電池工作示意圖
三星全新的微型燃料電池可以使發電機產生3瓦特的電力,足夠應付手機產品的使用需要,能夠為使用者提供平均使用狀況下連續10個小時的手機電量,比一般的充電電池的電量續航能力高出了2倍左右。
Oh Yong-soo表示,如果不出意外的話,使用“水燃料”發電的微型燃料電池最早在2010年就可以正式上市銷售、裝備手機產品了,屆時,相信三星公司一定會引起一場手機電池技術的變革,讓手機電池消費正式進入綠色環保時代。
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燃料電池原理搜尋結果
1. 燃料電池原理
燃料電池的運作原理(如圖1),也就是電池含有陰陽兩個電極,分別充滿電解液,而兩個電極間則為具有滲透性的薄膜所構成。氫氣由燃料電池的陽極進入,氧氣(或空氣)則 ...idic.tier.org.tw/TFCF/data/name/name_2_1.htm - 9k - 頁庫存檔 - 類似網頁
2. 氫能利用技術-燃料電池
燃料電池的歷史可以追朔到1839年,由英國法官威廉葛洛夫(William Grove)在一項業餘的實驗中神奇的發現了燃料電池的發電原理;但當時因為電極材料問題,使這項發明未受 ...idic.tier.org.tw/TFCF/data/name/name_1_6_8.htm - 17k - 頁庫存檔 - 類似網頁
3. [PDF]
氫燃料電池-能源明日之星氫燃料電池是什麼?
檔案類型: PDF/Adobe Acrobat - HTML 版氫氧燃料電池作用原理是以氫氣為燃料,和氧氣經電化學反應後透過質子交換膜 ... 而燃料電池的作動原理則剛好與水電解的電化學反應現象相反,也就 ...www.mingdao.edu.tw/physics/pdf_page/Lesson_5.pdf - 類似網頁
4. [PDF]
燃料電池原理、應用、設計及測試技術講座
檔案類型: PDF/Adobe Acrobat課程目標: 瞭解各種燃料電池的操作原理,以及熱力學及電化學原理;進一步瞭解各種 ... 課程目標: 協助學員瞭解高分子薄膜燃料電池工作原理、基本結構、發電效能,及 ...my.nthu.edu.tw/~ceer/chinese/c_activity/cooperation/Fuel%20Cell.pdf - 類似網頁
5. 燃料電池
簡單來說,燃料電池是一種直接將燃料之化學能轉換為電能的裝置,運作原理可解釋為水電解的逆反應。構成燃料電池得基本元件包括電極(electrode)、電解質 ...www.che.yuntech.edu.tw/Functional%20polymer%20La/fuel%20cell%20introduction%20one.htm - 21k - 頁庫存檔 - 類似網頁
6. [PDF]
燃料電池的原理與特性
檔案類型: PDF/Adobe Acrobat - HTML 版燃料電池的原理與特性. 作者. 張榮傑。高雄縣中山工商。綜合高中。二年六班 .... 燃料 電池的運作原理,是電池的陰陽兩個電極,分別充滿電解液,而兩個電極間 ...www.shs.edu.tw/works/essay/2008/03/2008033122510990.pdf - 類似網頁
7. 燃料電池原理- 其它機器人- Robofun 機器人論壇- Powered by Discuz!
1 篇文章 - 1 位作者 - 上一則文章: 2006年2月2日
Robofun 機器人論壇燃料電池原理http://www.nenryoudenchi.co.jp/speecys-fc.html http://www.speecys.com/lineup.html ...www.robofun.net/forum/viewthread.php?tid=510&extra=page%3D5 - 19k - 頁庫存檔 - 類似網頁
8. 博客來書籍館>燃料電池-原理與應用
燃料電池-原理與應用衣寶蓮/著. ... 本書簡述了燃料電池的工作原理,關鍵材料的特徵與製備技術,電池組與電池系統的設計、製造與性能,以及燃料電池在航太、民生用電 ...www.books.com.tw/exep/prod/booksfile.php?item=0010290473 - 17k - 頁庫存檔 - 類似網頁
9. 工研院學習服務網-課程公告-燃料電池技術系列(新竹場)-質子交換膜燃料 ...
將著重於質子交換膜燃料電池之基本反應原理與水熱管理操作技術解說,並完整介紹電池組流場與結構之 ... 單元二:質子交換膜燃料電池原理與設計97/09/18(四)13:30~16:30 ...college.itri.org.tw/SeminarView1.aspx?no=23081854&msgno=303114 - 28k - 頁庫存檔 - 類似網頁
10. 燃料電池:原理·技術·應用----中國圖書網(網上書店)
本書簡述了燃料電池的工作原理,關鍵材料的特徵與製備技術,電池組與電池系統的設計、 製備、集成與性能,以及燃料電池技術在航太、民用發電及電汽車等領域的應用。 ...www.bookschina.com.tw/1084950.htm - 43k - 頁庫存檔 - 類似網頁
相關搜尋:
甲醇燃料電池原理
氫燃料電池原理
直接甲醇燃料電池原理
燃料電池原理與應用
燃料電池的原理
燃料電池
燃料電池車
燃料電池公司
燃料電池應用
生物燃料電池
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燃料电池
维基百科,自由的百科全书
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燃料电池(Fuel cell),是一种使用燃料进行化学反应产生电力的装置,最早于1839年由英国的Grove所发明。最常见是以氢氧为燃料的质子交换膜燃料电池,由于燃料价格平宜,加上对人体无化学危险、对环境无害,发电后产生纯水和热,1960年代应用在美国军方,后于1965年应用于美国双子星计划双子星5号太空仓。现在也有一些笔记型电脑开始研究使用燃料电池。但由于产生的电量太小,且无法瞬间提供大量电能,只能用于平稳供电上。
燃料电池是一个电池本体与燃料箱组合而成的动力机制。燃料的选择性非常高,包括纯氢气、甲醇、乙醇、天然气,甚至于现在运用最广泛的汽油,都可以做为燃料电池的燃料。这是目前其他所有动力来源无法做到的。而以燃料电池做为汽车的动力,已被公认是廿一世纪必然的趋势。
甲醇燃料电池,燃料电池的层状结构(中心立方体)
燃料电池是以电的化学效应来进行发电,在我们的生活中有许多电池都是利用电的化学效应来发电,或储存电力;干电池、碱性电池、铅蓄电池都是以正负极金属的活性高低差来产生电位差的电的化学发电机,通称伏打电池。
燃料电池则是以具有可燃性的燃料与氧反应产生电力;通常可燃性燃料如瓦斯、汽油、甲烷(CH4)、乙醇(酒精)、氢…这些可燃性物质都要经过燃烧加热水使水沸腾,而使水蒸气推动涡轮发电,以这种转换方式大部分的能量通常都转为无用的热能,转换效率通常只有约30%相当的低,而燃料电池是以特殊催化剂使燃料与氧发生反应产生二氧化碳(CO2)和水(H2O),因不需推动涡轮等发电器具,也不需将水加热至水蒸气再经散热变回水,所以能量转换效率高达70%左右,足足比一般发电方法高出了约40%;优点还不只如此,二氧化碳排放量比一般方法低许多,水又是无害的产生物,是一种低污染性的能源。
[编辑] 外部联接
[北京金能燃料电池有限公司]
fuel cell
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An electrochemical cell in which the energy of a reaction between a fuel, such as liquid hydrogen, and an oxidant, such as liquid oxygen, is converted directly and continuously into electrical energy.
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Sci-Tech Encyclopedia: Fuel cell
An electrical cell that converts the intrinsic chemical free energy of a fuel directly into direct-current electrical energy in a continuous catalytic process. As in the classical definition of catalysis, the fuel cell should not itself undergo change; that is, unlike the electrodes of a battery, its electrodes ideally remain invariant. For most fuel-oxidant combinations, the available free energy of combustion is somewhat less than the heat of combustion. In a typical thermal power conversion process, the heat of combustion of the fuel is turned into electrical work via a Carnot heat-engine cycle coupled with a rotating electrical generator. Since the Carnot conversion rarely proceeds at an efficiency exceeding 40% because of heat source and sink temperature limitations, the efficiency of conversion in a fuel cell can be greater than in a heat engine, especially in small devices. See also Catalysis.
The fuel cell reaction usually involves the combination of hydrogen (H) with oxygen (O) [reaction (1)]. Under standard conditions of temperature and pressure, 25°C (77°F) and 1 atm (100 kilopascals), the reaction takes place with a free-energy change ΔG = −56.69 kcal (237 kilojoules) per mole of water. Since the formation of water involves two electrons, this value corresponds to −1.23 electronvolts (1 eV = 23.06 kcal/equivalent). Thus, at thermodynamic equilibrium (zero current), the cell voltage should be 1.23 V, yielding a theoretical efficiency based on the heat of combustion [ΔH for H2O(l) = −1.48 eV] of 83.1%. See also Free energy.
At a net (nonzero) current, all cells show losses in cell voltage (V). In low-temperature fuel cells, these are due largely to the kinetic slowness (irreversibility) of the oxygen reduction reaction, which requires the breaking of a double bond with transfer of four electrons per molecule in a complex sequence of reactions. In high-temperature systems, oxygen reduction losses are less significant, since the reaction rate increases with temperature. However, the available free energy then decreases, falling to a value corresponding to about 1.0 V at 1000°C (1832°F). A further thermodynamic loss results from high cell fuel (or oxidant) conversion to avoid waste, so that the effective reversible potential is displaced from the standard state. Thus, at high temperature, the major loss is thermodynamic, which tends to compensate for the irreversible oxygen electrode losses at low temperature. As a result, cell voltages under typical loads vary from about 0.6 V for simple terrestrial cells to 1.0 V for aerospace cells. Cell voltage falls with increasing current per unit area. Since thermal efficiency is given by V/1.48, cell performance is a compromise between relative cost (that is, kilowatts available per unit area) and fuel efficiency, to give the lowest cost of electricity for a given application. See also Oxidation-reduction.
While any chemically suitable fuel, including metals such as lithium (Li), sodium (Na), aluminum (Al), and zinc (Zn), may be used in a fuel cell, hydrocarbons (for example, natural gas) will not react at a significant rate in low-temperature fuel cells. They will crack thermally before reacting electrochemically if injected directly into high-temperature fuel cells. Simple low-power units operating directly on methanol at ambient temperature do find some use, and liquid-fueled hydrazine cells have also found specialized applications. However, the high manufacturing energy requirement for hydrazine, together with its high cost and hazardous nature, leaves hydrogen the only suitable general high-performance fuel candidate. See also Hydrazine; Hydrogen; Methanol.
For practical fuel cells, hydrogen can be produced from readily available fuels such as clean light distillate (for example, naphtha), usually by steam reforming, or from coal via gasification at high temperature (the direct use of coal or carbon has been abandoned). In the high-temperature cells under certain conditions, internal steam reforming of simple hydrocarbons and alcohols (for example methane and methanol) can take place by the injection of the fuel with steam, which avoids cracking. Since methanol fuel reacts only slowly at low temperature, it is also steam-reformed to hydrogen. Methanol reforming takes place at only about 250°C (480°F), giving mixtures of hydrogen and carbon dioxide (CO2) with a small amount of carbon monoxide (CO). In contrast, steam reforming of higher-molecular-weight alcohols or clean light distillates requires temperatures in excess of 700°C (1290°F). This favors mixtures of hydrogen and carbon monoxide, as in coal synthesis gas.
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fuel cell
A pollution-free electricity generation technology that is expected to compete with traditional methods of creating and distributing electricity. It is also expected to be used in electrically powered cars, trucks and buses. On-the-road testing began with prototype vehicles at the end of the 20th century. Self-contained fuel cell systems are also expected to power individual homes within 20 years.
Like a Battery
Functioning similar to a battery, which uses electrochemical conversion, fuel cells take in hydrogen-rich fuel and oxygen and turn them into electricity and heat. The waste product is water. The hydrogen can be derived from gasoline, natural gas, propane or methanol.
The hydrogen, which comes into the anode side of the fuel cell, is converted into electrons and hydrogen ions. The electrons are repelled by the anode and flow to the cathode. The cathode accepts the electrons as well as oxygen, which combine with the hydrogen ions from the anode, and converts them into water.
The Energy Alternative?
Some predict this will be the largest, new industry of the 21st century, although there are many obstacles to overcome. It depends on which sources for hydrogen ultimately make sense. By itself, hydrogen is difficult to distribute and stockpile, and installing hydrogen pumps in every gas station would be a gigantic undertaking. Currently, Ballard Power Systems, Inc., Burnaby, British Columbia www.ballard.com.is the largest company making fuel cells.
A Ballard Fuel Cell
The core of this fuel cell comprises two electrodes (anode and cathode) separated by a polymer exchange membrane. Each electrode is coated on one side with a platinum catalyst, which causes the hydrogen fuel to separate into free electrons and protons (positive hydrogen ions) at the anode. The free electrons are conducted in the form of usable electrical current through an external circuit. The protons migrate through the membrane electrolyte to the cathode, where the catalyst causes the protons to combine with oxygen from the air and electrons from the external circuit to form water and heat. (Image courtesy of Ballard Power Systems.)
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An electrochemical cell in which the energy of a reaction between a fuel, such as liquid hydrogen, and an oxidant, such as liquid oxygen, is converted directly and continuously into electrical energy.
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Sci-Tech Encyclopedia: Fuel cell
An electrical cell that converts the intrinsic chemical free energy of a fuel directly into direct-current electrical energy in a continuous catalytic process. As in the classical definition of catalysis, the fuel cell should not itself undergo change; that is, unlike the electrodes of a battery, its electrodes ideally remain invariant. For most fuel-oxidant combinations, the available free energy of combustion is somewhat less than the heat of combustion. In a typical thermal power conversion process, the heat of combustion of the fuel is turned into electrical work via a Carnot heat-engine cycle coupled with a rotating electrical generator. Since the Carnot conversion rarely proceeds at an efficiency exceeding 40% because of heat source and sink temperature limitations, the efficiency of conversion in a fuel cell can be greater than in a heat engine, especially in small devices. See also Catalysis.
The fuel cell reaction usually involves the combination of hydrogen (H) with oxygen (O) [reaction (1)]. Under standard conditions of temperature and pressure, 25°C (77°F) and 1 atm (100 kilopascals), the reaction takes place with a free-energy change ΔG = −56.69 kcal (237 kilojoules) per mole of water. Since the formation of water involves two electrons, this value corresponds to −1.23 electronvolts (1 eV = 23.06 kcal/equivalent). Thus, at thermodynamic equilibrium (zero current), the cell voltage should be 1.23 V, yielding a theoretical efficiency based on the heat of combustion [ΔH for H2O(l) = −1.48 eV] of 83.1%. See also Free energy.
At a net (nonzero) current, all cells show losses in cell voltage (V). In low-temperature fuel cells, these are due largely to the kinetic slowness (irreversibility) of the oxygen reduction reaction, which requires the breaking of a double bond with transfer of four electrons per molecule in a complex sequence of reactions. In high-temperature systems, oxygen reduction losses are less significant, since the reaction rate increases with temperature. However, the available free energy then decreases, falling to a value corresponding to about 1.0 V at 1000°C (1832°F). A further thermodynamic loss results from high cell fuel (or oxidant) conversion to avoid waste, so that the effective reversible potential is displaced from the standard state. Thus, at high temperature, the major loss is thermodynamic, which tends to compensate for the irreversible oxygen electrode losses at low temperature. As a result, cell voltages under typical loads vary from about 0.6 V for simple terrestrial cells to 1.0 V for aerospace cells. Cell voltage falls with increasing current per unit area. Since thermal efficiency is given by V/1.48, cell performance is a compromise between relative cost (that is, kilowatts available per unit area) and fuel efficiency, to give the lowest cost of electricity for a given application. See also Oxidation-reduction.
While any chemically suitable fuel, including metals such as lithium (Li), sodium (Na), aluminum (Al), and zinc (Zn), may be used in a fuel cell, hydrocarbons (for example, natural gas) will not react at a significant rate in low-temperature fuel cells. They will crack thermally before reacting electrochemically if injected directly into high-temperature fuel cells. Simple low-power units operating directly on methanol at ambient temperature do find some use, and liquid-fueled hydrazine cells have also found specialized applications. However, the high manufacturing energy requirement for hydrazine, together with its high cost and hazardous nature, leaves hydrogen the only suitable general high-performance fuel candidate. See also Hydrazine; Hydrogen; Methanol.
For practical fuel cells, hydrogen can be produced from readily available fuels such as clean light distillate (for example, naphtha), usually by steam reforming, or from coal via gasification at high temperature (the direct use of coal or carbon has been abandoned). In the high-temperature cells under certain conditions, internal steam reforming of simple hydrocarbons and alcohols (for example methane and methanol) can take place by the injection of the fuel with steam, which avoids cracking. Since methanol fuel reacts only slowly at low temperature, it is also steam-reformed to hydrogen. Methanol reforming takes place at only about 250°C (480°F), giving mixtures of hydrogen and carbon dioxide (CO2) with a small amount of carbon monoxide (CO). In contrast, steam reforming of higher-molecular-weight alcohols or clean light distillates requires temperatures in excess of 700°C (1290°F). This favors mixtures of hydrogen and carbon monoxide, as in coal synthesis gas.
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Computer Desktop Encyclopedia: fuel cell
A pollution-free electricity generation technology that is expected to compete with traditional methods of creating and distributing electricity. It is also expected to be used in electrically powered cars, trucks and buses. On-the-road testing began with prototype vehicles at the end of the 20th century. Self-contained fuel cell systems are also expected to power individual homes within 20 years.
Like a Battery
Functioning similar to a battery, which uses electrochemical conversion, fuel cells take in hydrogen-rich fuel and oxygen and turn them into electricity and heat. The waste product is water. The hydrogen can be derived from gasoline, natural gas, propane or methanol.
The hydrogen, which comes into the anode side of the fuel cell, is converted into electrons and hydrogen ions. The electrons are repelled by the anode and flow to the cathode. The cathode accepts the electrons as well as oxygen, which combine with the hydrogen ions from the anode, and converts them into water.
The Energy Alternative?
Some predict this will be the largest, new industry of the 21st century, although there are many obstacles to overcome. It depends on which sources for hydrogen ultimately make sense. By itself, hydrogen is difficult to distribute and stockpile, and installing hydrogen pumps in every gas station would be a gigantic undertaking. Currently, Ballard Power Systems, Inc., Burnaby, British Columbia www.ballard.com.is the largest company making fuel cells.
A Ballard Fuel Cell
The core of this fuel cell comprises two electrodes (anode and cathode) separated by a polymer exchange membrane. Each electrode is coated on one side with a platinum catalyst, which causes the hydrogen fuel to separate into free electrons and protons (positive hydrogen ions) at the anode. The free electrons are conducted in the form of usable electrical current through an external circuit. The protons migrate through the membrane electrolyte to the cathode, where the catalyst causes the protons to combine with oxygen from the air and electrons from the external circuit to form water and heat. (Image courtesy of Ballard Power Systems.)
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Britannica Concise Encyclopedia: fuel cell
Device that converts chemical energy of a fuel directly into electricity (see electrochemistry). Fuel cells are intrinsically more efficient than most other energy-conversion devices. Electrolytic chemical reactions cause electrons to be released on one electrode and flow through an external circuit to a second electrode. Whereas in batteries the electrodes are the source of the active ingredients, which are altered and depleted during the reaction, in fuel cells the gas or liquid fuel (often hydrogen, methyl alcohol, hydrazine, or a simple hydrocarbon) is supplied continuously to one electrode and oxygen or air to the other from an external source. So, as long as fuel and oxidant are supplied, the fuel cell will not run down or require recharging. Fuel cells can be used in place of virtually any other source of electricity. They are especially being developed for use in electric automobiles, in the hope of achieving enormous reductions in pollution.
For more information on fuel cell, visit Britannica.com.
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Columbia Encyclopedia: fuel cell,
electric cell in which the chemical energy from the oxidation of a gas fuel is converted directly to electrical energy in a continuous process (see oxidation and reduction). The efficiency of conversion from chemical to electrical energy in a fuel cell is between 65% and 80%, nearly twice that of the usual indirect method of conversion in which fuels are used to heat steam to turn a turbine connected to an electric generator. The earliest fuel cell, in which hydrogen and oxygen were combined to form water, was constructed in 1829 by the Englishman William Grove. In the hydrogen and oxygen fuel cell, hydrogen and oxygen gas are bubbled into separate compartments connected by a porous disk through which an electrolyte such as aqueous potassium hydroxide (KOH) can move. Inert graphite electrodes, mixed with a catalyst such as platinum, are dipped into each compartment. When the two electrodes are connected by a wire, the combination of electrodes, wire, and electrolyte form a complete circuit, and an oxidation-reduction reaction takes place in the cell: hydrogen gas is oxidized to form water at the anode, or hydrogen electrode; electrons are liberated in this process and flow through the wire to the cathode, or oxygen electrode; and at the cathode the electrons combine with the oxygen gas and reduce it. The modern hydrogen-oxygen cell, operating at about 250°C and a pressure of 50 atmospheres, gives a maximum voltage of about 1 volt. Fuel cells have been used to generate electricity in space flights.
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Wikipedia: fuel cell
Methanol fuel cell. The actual fuel cell stack is the layered cubic structure in the center of the image
A fuel cell is an electrochemical energy conversion device. It produces electricity from external supplies of fuel (on the anode side) and oxidant (on the cathode side). These react in the presence of an electrolyte. Generally, the reactants flow in and reaction products flow out while the electrolyte remains in the cell. Fuel cells can operate virtually continuously as long as the necessary flows are maintained.
Fuel cells are different from batteries in that they consume reactant, which must be replenished, while batteries store electrical energy chemically in a closed system. Additionally, while the electrodes within a battery react and change as a battery is charged or discharged, a fuel cell's electrodes are catalytic and relatively stable.
Many combinations of fuel and oxidant are possible. A hydrogen cell uses hydrogen as fuel and oxygen as oxidant. Other fuels include hydrocarbons and alcohols. Other oxidants include air, chlorine and chlorine dioxide.[1]
Fuel cell design
In essence, a fuel cell works by catalysis, separating the component electrons and protons of the reactant fuel, and forcing the electrons to travel through a circuit, hence converting them to electrical power. Another catalytic process takes the electrons back in, combining them with the protons and the oxidant to form waste products (typically simple compounds like water and carbon dioxide).
In the archetypal hydrogen–oxygen proton exchange membrane fuel cell (PEMFC) design, a proton-conducting polymer membrane, (the electrolyte), separates the anode and cathode sides. This was called a "solid polymer electrolyte fuel cell" (SPEFC) in the early 1970s, before the proton exchange mechanism was well-understood. (Notice that "polymer electrolyte membrane" and "proton exchange membrane" result in the same acronym.)
On the anode side, hydrogen diffuses to the anode catalyst where it later dissociates into protons and electrons. The protons are conducted through the membrane to the cathode, but the electrons are forced to travel in an external circuit (supplying power) because the membrane is electrically insulating. On the cathode catalyst, oxygen molecules react with the electrons (which have traveled through the external circuit) and protons to form water — in this example, the only waste product, either liquid or vapor.
In addition to this pure hydrogen type, there are hydrocarbon fuels for fuel cells, including diesel, methanol (see: direct-methanol fuel cells) and chemical hydrides. The waste products with these types of fuel are carbon dioxide and water.
Construction of a low temperature PEMFC: Bipolar plate as electrode with in-milled gas channel structure, fabricated from conductive plastics (enhanced with carbon nanotubes for more conductivity); Porous carbon papers; reactive layer, usually on the polymer membrane applied; polymer membrane.
The materials used in fuel cells differ by type. The electrode–bipolar plates are usually made of metal, nickel or carbon nanotubes, and are coated with a catalyst (like platinum, nano iron powders or palladium) for higher efficiency. Carbon paper separates them from the electrolyte. The electrolyte could be ceramic or a membrane.
A typical PEM fuel cell produces a voltage from 0.6 to 0.7 at full rated load. Voltage decreases as current increases, due to several factors:
Activation loss
Ohmic loss (voltage drop due to resistance of the cell components and interconnects)
Mass transport loss (depletion of reactants at catalyst sites under high loads, causing rapid loss of voltage)[2]
To deliver the desired amount of energy, the fuel cells can be combined in series and parallel circuits, where series yield higher voltage, and parallel allows a stronger current to be drawn, this design is referred to as a fuel cell stack. Further, the cell surface area can be increased, to allow stronger current from each cell.
Fuel cell design issues
Costs. In 2002, typical cells had a catalyst content of US$1000 per kilowatt of electric power output. The goal is to reduce the cost in order to compete with current market technologies including gasoline internal combustion engines. Many companies are working on techniques to reduce cost in a variety of ways including reducing the amount of platinum needed in each individual cell. Ballard Power Systems have experiments with a catalyst enhanced with carbon silk which allows a 30% reduction (1 mg/cm² to 0.7 mg/cm²) in platinum usage without reduction in performance.[3]
The production costs of the PEM (proton exchange membrane). The Nafion® membrane currently costs €400/m². This, and the Toyota PEM and 3M PEM membrane can be replaced with the ITM Power membrane (a hydrocarbon polymer), resulting in a price of ~€4/m². in 2005 Ballard Power Systems announced that its fuel cells will use Solupor®, a porous polyethylene film patented by DSM.[4][5]
Water management (in PEMFCs). In this type of fuel cell, the membrane must be hydrated, requiring water to be evaporated at precisely the same rate that it is produced. If water is evaporated too quickly, the membrane dries, resistance across it increases, and eventually it will crack, creating a gas "short circuit" where hydrogen and oxygen combine directly, generating heat that will damage the fuel cell. If the water is evaporated too slowly, the electrodes will flood, preventing the reactants from reaching the catalyst and stopping the reaction. Methods to manage water in cells are being developed by fuel cell companies and academic research labs.[6]
Flow control. Just as in a combustion engine, a steady ratio between the reactant and oxygen is necessary to keep the fuel cell operating efficiently.
Temperature management. The same temperature must be maintained throughout the cell in order to prevent destruction of the cell through thermal loading. This is particularly challenging as the H2 + O2 -> H20 reaction is highly exothermic, so a large quantity of heat is generated within the fuel cell.
Durability, service life, and special requirements for some type of cells. Stationary applications typically require more than 40,000 hours of reliable operation at a temperature of -35 °C to 40 °C, while automotive fuel cells require a 5,000 hour lifespan (the equivalent of 150,000 miles) under extreme temperatures. Automotive engines must also be able to start reliably at -30 °C and have a high power to volume ratio (typically 2.5 kW per liter).
Limited carbon monoxide tolerance of the anode.
History
The principle of the fuel cell was discovered by German scientist Christian Friedrich Schönbein in 1838 and published in the January 1839 edition of the "Philosophical Magazine".[7] Based on this work, the first fuel cell was developed by Welsh scientist Sir William Robert Grove in 1843. The fuel cell he made used similar materials to today's phosphoric-acid fuel cell. In 1955, W. Thomas Grubb, a chemist working for the General Electric Company (GE), further modified the original fuel cell design by using a sulphonated polystyrene ion-exchange membrane as the electrolyte. Three years later another GE chemist, Leonard Niedrach, devised a way of depositing platinum onto the mebrane, which served as catalyst for the necessary hydrogen oxidation and oxygen reduction reactions. This became known as the 'Grubb-Niedrach fuel cell'. GE went on to develop this technology with NASA, leading to it being used on the Gemini space project. This was the first commercial use of a fuel cell. It wasn't until 1959 that British engineer Francis Thomas Bacon successfully developed a 5 kW stationary fuel cell. In 1959, a team led by Harry Ihrig built a 15 kW fuel cell tractor for Allis-Chalmers which was demonstrated across the US at state fairs. This system used potassium hydroxide as the electrolyte and compressed hydrogen and oxygen as the reactants. Later in 1959, Bacon and his colleagues demonstrated a practical five-kilowatt unit capable of powering a welding machine. In the 1960s, Pratt and Whitney licensed Bacon's U.S. patents for use in the U.S. space program to supply electricity and drinking water (hydrogen and oxygen being readily available from the spacecraft tanks).
UTC's Power subsidiary was the first company to manufacture and commercialize a large, stationary fuel cell system for use as a co-generation power plant in hospitals, universities and large office buildings. UTC Power continues to market this fuel cell as the PureCell 200, a 200 kW system.[8] UTC Power continues to be the sole supplier of fuel cells to NASA for use in space vehicles, having supplied the Apollo missions and currently the Space Shuttle program, and is developing fuel cells for automobiles, buses, and cell phone towers; the company has demonstrated the first fuel cell capable of starting under freezing conditions with its proton exchange membrane automotive fuel cell.
Types of fuel cells
Fuel Cell Name
Electrolyte
Qualified Power (W)
Working Temperature (°C)
Electrical efficiency
Status
Metal hydride fuel cell
Aqueous alkaline solution (e.g.potassium hydroxide)
?
above -20 50%Ppeak @ 0
?
Commercial/Research
Electro-galvanic fuel cell
Aqueous alkaline solution (e.g., potassium hydroxide)
?
under 40
?
Commercial/Research
Direct formic acid fuel cell (DFAFC)
Polymer membrane (ionomer)
to 50 W
under 40
?
Commercial/Research
Zinc-air battery
Aqueous alkaline solution (e.g., potassium hydroxide)
?
under 40
?
Mass production
Microbial fuel cell
Polymer membrane or humic acid
?
under 40
?
Research
Upflow microbial fuel cell (UMFC)
?
under 40
?
Research
Reversible fuel cell
Polymer membrane (ionomer)
?
under 50
?
Commercial/Research
Direct borohydride fuel cell
Aqueous alkaline solution (e.g., sodium hydroxide)
?
70
?
Commercial
Alkaline fuel cell
Aqueous alkaline solution (e.g., potassium hydroxide)
10 kW to 100 kW
under 80
Cell: 60–70%System: 62%
Commercial/Research
Direct methanol fuel cell
Polymer membrane (ionomer)
100 kW to 1 mW
90–120
Cell: 20–30%System: 10–20%
Commercial/Research
Reformed methanol fuel cell
Polymer membrane (ionomer)
5 W to 100 kW
(Reformer)250–300(PBI)125–200
Cell: 50–60%System: 25–40%
Commercial/Research
Direct-ethanol fuel cell
Polymer membrane (ionomer)
up to 140 mW/cm²
above 25? 90–120
?
Research
Formic acid fuel cell
Polymer membrane (ionomer)
?
90–120
?
Research
Proton exchange membrane fuel cell
Polymer membrane (ionomer) (e.g., Nafion® or Polybenzimidazole fiber)
100 W to 500 kW
(Nafion)70–120(PBI)125–220
Cell: 50–70%System: 30–50%
Commercial/Research
RFC - Redox
Liquid electrolytes with redox shuttle & polymer membrane (Ionomer)
1 kW to 10 MW
?
?
Research
Phosphoric acid fuel cell
Molten phosphoric acid (H3PO4)
up to 10 MW
150-200
Cell: 55%System: 40%Co-Gen: 90%
Commercial/Research
Molten carbonate fuel cell
Molten alkaline carbonate (e.g., sodium bicarbonate NaHCO3)
100 MW
600-650
Cell: 55%System: 47%
Commercial/Research
Tubular solid oxide fuel cell (TSOFC)
600-650
Research
Protonic ceramic fuel cell
H+-conducting ceramic oxide
?
700
?
Research
Direct carbon fuel cell
Several different
?
700-850
Cell: 80%System: 70%
Commercial/Research
Solid oxide fuel cell
O2--conducting ceramic oxide (e.g., zirconium dioxide, ZrO2)
up to 100 MW
700–1000
Cell: 60–65%System: 55–60%
Commercial/Research
Efficiency
Fuel cell efficiency
The efficiency of a fuel is dependent on the amount of power drawn from it. Drawing more power means drawing more current, which increases the losses in the fuel cell. As a general rule, the more power (current) drawn, the lower the efficiency. Most losses manifest themselves as a voltage drop in the cell, so the efficiency of a cell is almost proportional to its voltage. For this reason, it is common to show graphs of voltage versus current (so-called polarization curves) for fuel cells. A typical cell running at 0.7 V has an efficiency of about 50%, meaning that 50% of the energy content of the hydrogen is converted into electrical energy; the remaining 50% will be converted into heat. (Depending on the fuel cell system design, some fuel might leave the system unreacted, constituting an additional loss.)
For a hydrogen cell operating at standard conditions with no reactant leaks, the efficiency is equal to the cell voltage divided by 1.48 V, based on the enthalpy, or heating value, of the reaction. For the same cell, the second law efficiency is equal to cell voltage divided by 1.23 V. (This voltage varies with fuel used, and quality and temperature of the cell.) The difference between these number represents the difference between the reaction's enthalpy and Gibbs free energy. This difference always appears as heat, along with any losses in electrical conversion efficiency.[2]
Fuel cells are not constrained by the maximum Carnot cycle efficiency as combustion engines are, because they do not operate with a thermal cycle. At times, this is misrepresented when fuel cells are stated to be exempt from the laws of thermodynamics. Instead, it can be described that the "limitations imposed by the second law of thermodynamics on the operation of fuel cells are much less severe than the limitations imposed on conventional energy conversion systems".[9] Consequently, they can have very high efficiencies in converting chemical energy to electrical energy, especially when they are operated at low power density, and using pure hydrogen and oxygen as reactants.
In practice
For a fuel cell operated on air (rather than bottled oxygen), losses due to the air supply system must also be taken into account. This refers to the pressurization of the air and adding moisture to it. This reduces the efficiency significantly and brings it near to the efficiency of a compression ignition engine. Furthermore fuel cells have lower efficiencies at higher loads.
The tank-to-wheel efficiency of a fuel cell vehicle is about 45% at low loads and shows average values of about 36% when a driving cycle like the NEDC (New European Driving Cycle) is used as test procedure.[10] The comparable NEDC value for a Diesel vehicle is 22%.
It is also important to take losses due to production, transportation, and storage into account. Fuel cell vehicles running on compressed hydrogen may have a power-plant-to-wheel efficiency of 22% if the hydrogen is stored as high-pressure gas, and 17% if it is stored as liquid hydrogen.[11]
Fuel cells cannot store energy like a battery, but in some applications, such as stand-alone power plants based on discontinuous sources such as solar or wind power, they are combined with electrolyzers and storage systems to form an energy storage system. The overall efficiency (electricity to hydrogen and back to electricity) of such plants (known as round-trip efficiency) is between 30 and 50%, depending on conditions.[12] While a much cheaper lead-acid battery might return about 90%, the electrolyzer/fuel cell system can store indefinite quantities of hydrogen, and is therefore better suited for long-term storage.
Solid-oxide fuel cells produce exothermic heat from the recombination of the oxygen and hydrogen. The ceramic can run as hot as 800 degrees Celsius. This heat can be captured and used to heat water in a combined heat and power (CHP) application. When the heat is captured, total efficiency can reach 80-90%. CHP units are being developed today for the European home market.
Fuel cell applications
Fuel cells are very useful as power sources in remote locations, such as spacecraft, remote weather stations, large parks, rural locations, and in certain military applications. A fuel cell system running on hydrogen can be compact, lightweight and has no major moving parts. Because fuel cells have no moving parts, and do not involve combustion, in ideal conditions they can achieve up to 99.9999% reliability.[13] This equates to less than one minute of down time in a six year period.
A new application is micro combined heat and power, which is cogeneration for family homes, office buildings and factories. This type of system generates constant electric power (selling excess power back to the grid when it is not consumed), and at the same time produce hot air and water from the waste heat. A lower fuel-to-electricity conversion efficiency is tolerated (typically 15-20%), because most of the energy not converted into electricity is utilized as heat. Some heat is lost with the exhaust gas just as in a normal furnace, so the combined heat and power efficiency is still lower than 100%, typically around 80%. In terms of exergy however, the process is inefficient, and one could do better by maximizing the electricity generated and then using the electricity to drive a heat pump. Phosphoric-acid fuel cells (PAFC) comprise the largest segment of existing CHP products worldwide and can provide combined efficiencies close to 80% (45-50% electric + remainder as thermal). UTC Power is currently the world's largest manufacturer of PAFC fuel cells. Molten-carbonate fuel cells have also been installed in these applications, and solid-oxide fuel cell prototypes exist.
However, since electrolyzer systems do not store fuel in themselves, but rather rely on external storage units, they can be successfully applied in large-scale energy storage, rural areas being one example. In this application, batteries would have to be largely oversized to meet the storage demand, but fuel cells only need a larger storage unit (typically cheaper than an electrochemical device).
One such pilot program is operating on Stuart Island in Washington State. There the Stuart Island Energy Initiative [1]has built a complete, closed-loop system: Solar panels power an electrolyzer which makes hydrogen. The hydrogen is stored in a 500 gallon tank at 200 PSI, and runs a ReliOn fuel cell to provide full electric back-up to the off-the-grid residence. The SIEI website gives extensive technical details.
The world's first Fuel Cell operated and certified passenger ship was the "HYDRA" (see picture). Mr. Christian Machens was the founder of the company "etaing GmbH" and realised this project with a small team of young engineers in Leipzig. It was christened in June 2000 in Bonn. The Fuel Cell System (AFC type, 6,5 kWel net output) was built in Wurzen near Leipzig, the hull was built in Hamburg and it was certified by the Germanischer Lloyd (Hamburg). The boat has transported around 2.000 persons without any major technical problems. The main advantages of the AFC technology are that the system can start at freezing temperatures (-10°C) and is not sensitive to a salty environment.
Suggested applications
Base load power plants
Electric and hybrid vehicles.
Auxiliary power
Off-grid power supply
Notebook computers for applications where AC charging may not be available for weeks at a time.
Portable charging docks for small electronics (e.g. a belt clip that charges your cell phone or PDA).
Hydrogen transportation and refueling
Toyota FCHV PEM FC fuel cell vehicle
For more details on this topic, see Hydrogen station.
The first public hydrogen refueling station was opened in Reykjavík, Iceland in April 2003. This station serves three buses built by DaimlerChrysler that are in service in the public transport net of Reykjavík. The station produces the hydrogen it needs by itself, with an electrolyzing unit (produced by Norsk Hydro), and does not need refilling: all that enters is electricity and water. Royal Dutch Shell is also a partner in the project. The station has no roof, in order to allow any leaked hydrogen to escape to the atmosphere.
For more details on this topic, see Hydrogen highway.
The GM 1966 Electrovan was the automotive industry's first attempt at an automobile powered by a hydrogen fuel cell. The Electrovan, which weighed more than twice as much as a normal van, could travel up to 70 miles an hour.[14][15]
The 2001 Chrysler Natrium used its own on-board hydrogen processor. It produces hydrogen for the fuel cell by reacting sodium borohydride fuel with Borax, both of which Chrysler claimed was naturally occurring in great quantity in the United States.[2] The hydrogen produces electric power in the fuel cell for near-silent operation and a range of 300 miles without impinging on passenger space. Chrysler also developed vehicles which separated hydrogen from gasoline in the vehicle, the purpose being to reduce emissions without relying on a nonexistent hydrogen infrastructure and to avoid large storage tanks.[16]
In 2005 the British firm Intelligent Energy produced the first ever working hydrogen run motorcycle called the ENV (Emission Neutral Vehicle). The motorcycle holds enough fuel to run for four hours, and to travel 100 miles in an urban area. Its top speed is 50 miles per hour.[17] Honda is also going to offer fuel-cell motorcycles.[18][19]
A hydrogen fuel cell public bus accelerating at traffic lights in Perth, Western Australia
There are numerous prototype or production cars and buses based on fuel cell technology being researched or manufactured. Research is ongoing at a variety of motor car manufacturers. Honda has announced the release of a hydrogen vehicle in 2008.[20]
Currently, a team of college students called Energy-Quest is planning to take a hydrogen fuel cell powered boat around the world (as well as other projects using efficient or renewable fuels). Their venture is called the Triton.[citation needed]Type 212 submarines use fuel cells to remain submerged for weeks without the need to surface.
Boeing researchers and industry partners throughout Europe are planning to conduct experimental flight tests in 2007 of a manned airplane powered only by a fuel cell and lightweight batteries. The Fuel Cell Demonstrator Airplane research project was completed recently and thorough systems integration testing is now under way in preparation for upcoming ground and flight testing. The Boeing demonstrator uses a Proton Exchange Membrane (PEM) fuel cell/lithium-ion battery hybrid system to power an electric motor, which is coupled to a conventional propeller.
Market structure
Not all geographic markets are ready for SOFC powered m-CHP appliances. Currently, the regions that the lead the race in Distributed Generation and deployment of fuel cell m-CHP units are the EU and Japan.[3]
Hydrogen economy
Main article: Hydrogen economy
Electrochemical extraction of energy from hydrogen via fuel cells is an especially clean and efficient method of meeting our power needs, and introduces the need for establishing the infrastructure for a hydrogen economy. It must however be noted that regarding the concept of the hydrogen vehicle, burning/combustion of hydrogen in an internal combustion engine (IC/ICE) is oftentimes confused with the electrochemical process of generating electricity via fuel cells (FC) in which there is no combustion (though there is a small byproduct of heat in the reaction). Both processes require the establishment of a hydrogen economy before they may be considered commercially viable. Hydrogen combustion is similar to petroleum combustion (minus the emissions) and is thus limited by the Carnot efficiency, but is completely different from the hydrogen fuel cell's chemical conversion process of hydrogen to electricity and water without combustion. Hydrogen fuel cells emit only water, while direct methane or natural gas conversions (whether IC or FC) generate carbon dioxide emissions.
Hydrogen is typically thought of as an energy carrier, and not generally as an energy source, because it is usually produced from other energy sources via petroleum combustion, wind power, or solar photovoltaic cells. Nevertheless, hydrogen may be considered an energy source when extracted from subsurface reservoirs of hydrogen gas, methane and natural gas (steam reforming and water gas shift reaction), coal (coal gasification) or oil shale (oil shale gasification).[citation needed] Electrolysis, which requires electricity, and high-temperature electrolysis/thermochemical production, which requires high temperatures (ideal for nuclear reactors), are two primary methods for the extraction of hydrogen from water.
As of 2005, 49.7% of the electricity produced in the United States comes from coal, 19.3% comes from nuclear, 18.7% comes from natural gas, 6.5% from hydroelectricity, 3% from petroleum and the remaining 2.8% mostly coming from geothermal, solar and biomass. [4] When hydrogen is produced through electrolysis, the energy comes from these sources. Though the fuel cell itself will only emit heat and water as waste, pollution is oftentimes produced to make the hydrogen that it runs on; unless it is either mined, or generated by solar, wind or other clean power sources. If fusion power were to become a viable energy source then this would provide a clean method of producing abundant electricity. Hydrogen production is only as clean as the energy sources used to produce it. A holistic approach has to take into consideration the impacts of an extended hydrogen scenario. This refers to the production, the use and the disposal of infrastructure and energy converters.
Nowadays low temperature fuel cell stacks proton exchange membrane fuel cell (PEMFC), direct methanol fuel cell (DMFC) and phosphoric acid fuel cell (PAFC) make extensive use of catalysts. Impurities poison or foul the catalysts (reducing activity and efficiency), thus higher catalyst densities are required.[21] Limited reserves of platinum quicken the synthesis of an inorganic complex very similar to the catalytic iron-sulfur core of bacterial hydrogenase to step in.[22] Although platinum is seen by some as one of the major "showstoppers" to mass market fuel cell commercialization companies, most predictions of platinum running out and/or platinum prices soaring do not take into account effects of thrifting (reduction in catalyst loading) and recycling. Recent research at Brookhaven National Laboratory could lead to the replacement of platinum by a gold-palladium coating which may be less susceptible to poisoning and thereby improve fuel cell lifetime considerably.[23] Current targets for a transport PEM fuel cells are 0.2 g/kW Pt – which is a factor of 5 decrease over current loadings – and recent comments from major original equipment manufacturers (OEMs) indicate that this is possible. Also it is fully anticipated that recycling of fuel cells components, including platinum, will kick-in.
Research and development
August 2005: Georgia Institute of Technology researchers use triazole to raise the operating temperature of PEM fuel cells from below 100 °C to over 120 °C, claiming this will require less carbon-monoxide purification of the hydrogen fuel.[24]
September 2005: Technical University of Denmark (DTU) scientists announced in September 2005 a method of storing hydrogen in the form of ammonia saturated into a salt tablet. They claim it will be an inexpensive and safe storage method.[25]
January 2006: Virent Energy Systems is working on developing a low cost method[26] for producing hydrogen on demand - from certain sugar/water mixtures (using one of glycerol, sorbitol, or hydrogenated glucose derivatives). Such a technology, if successful would solve many of the infrastructure (hydrogen storage) issues associated with the hydrogen economy.[27]
2006:Staxon introduced an inexpensive OEM fuel cell module for system integration. In 2006 Angstrom Power, a British Columbia based company, began commercial sales of portable devices using proprietary hydrogen fuel cell technology, trademarked as "micro hydrogen."[28][29]
May 2007: Purdue University researchers have developed a method that uses aluminum and gallium alloy to extract hydrogen from water. They state that "the hydrogen is generated on demand, so you only produce as much as you need when you need it."[30]
See also
Comparison of automobile fuel technologies
Distributed generation
Electrolysis
Flow battery
Future energy development
Hydrogen energy plant in Denmark
Hydrogen fuel
Hydrogen vehicle
Grid energy storage
High-temperature electrolysis
Hydrogen reformer
Hydrogen storage
Hydrogen technologies
Renewable energy
Solid oxide fuel cell
Water splitting
Fuel cell module
Fuel cell system
References
^ S. G. Meibuhr, Electrochim. Acta, 11, 1301 (1966)
^ a b Larminie, James (May 2003). Fuel Cell Systems Explained, Second Edition. SAE International. ISBN 0768012597.
^ "Ballard Power Systems: Commercially Viable Fuel Cell Stack Technology Ready by 2010", March 29, 2005. Retrieved on 2007-05-27.
^ EP patent 0950075, "Electrolytic Membrane, Method of Manufacturing it and Use", granted 2003-02-12, assigned to DSM
^ Ballard Uses Solupor (September 13, 2005). Retrieved on 2007-05-27.
^ http://microfluidics.asu.edu/fcells.html
^ History of Fuel Cells. Johnson Matthey plc.. Retrieved on 2007-05-27.
^ The PureCell 200 - Product Overview. UTC Power. Retrieved on 2007-05-27.
^ About Fuel Cells. MIT / NASA. Retrieved on 2007-05-27.
^ Fuel Cell Vehicles:Status 2007 (March 20, 2007). Retrieved on 2007-05-23.
^ Efficiency of Hydrogen PEFC, Diesel-SOFC-Hybrid and Battery Electric Vehicles (July 15, 2003). Retrieved on 2007-05-23.
^ (January 2006) "Round Trip Energy Efficiency of NASA Glenn Regenerative Fuel Cell System". Preprint. Retrieved on 2007-05-27.
^ Fuel Cell Basics: Benefits. Fuel Cells 2000. Retrieved on 2007-05-27.
^ Fuel Cell Vehicles:Status 2007 (March 20, 2007). Retrieved on 2007-05-23.
^ "An Electrovan, Not an Edsel" by Danny Hakim. New York Times. New York, N.Y.: November 17, 2002. pg. 3.2
^ Chrysler Fuel Cell Vehicles. allpar.com. Retrieved on 2007-05-27.
^ The ENV Bike. Intelligent Energy. Retrieved on 2007-05-27.
^ "Honda Develops Fuel Cell Scooter Equipped with Honda FC Stack", Honda Motor Co., August 24, 2004. Retrieved on 2007-05-27.
^ Bryant, Eric (July 21, 2005). Honda to offer fuel-cell motorcycle. autoblog.com. Retrieved on 2007-05-27.
^ "Honda readies fuel-cell car for 2008 launch", CBC News, September 25, 2006. Retrieved on 2007-05-27.
^ Faur-Ghenciu, Anca (April/May 2003). "Fuel Processing Catalysts for Hydrogen Reformate Generation for PEM Fuel Cells". FuelCell Magazine. Retrieved on 2007-05-27.
^ Borman, Stu (February 14, 2005). "Iron-Sulfur Core Assembled". Chemical & Engineering News 83 (7): 11. Retrieved on 2007-05-27.
^ Johnson, R. Colin. "Gold is key to ending platinum dissolution in fuel cells", EETimes.com, January 22, 2007. Retrieved on 2007-05-27.
^ "Chemical Could Revolutionize Polymer Fuel Cells", Georgia Institute of Technology, August 24, 2005. Retrieved on 2007-05-27.
^ http://www.fuelcelltoday.com/FuelCellToday/IndustryInformation/IndustryInformationExternal/NewsDisplayArticle/0,1602,6487,00.html
^ Virent Energy Systems: FAQ. Virent Energy Systems, Inc. Retrieved on 2007-08-12.
^ Stitt, Jason. "Virent shows off its hydrogen-fuel plans", Wisconsin Technology Network LLC, June 6, 2004. Retrieved on 2007-05-27.
^ Angstrom Power products. Retrieved on 2007-07-03.
^ Micro-Fuel Cell Blog. Retrieved on 2007-07-03.
^ "New process generates hydrogen from aluminum alloy to run engines, fuel cells", Physorg.com, May 16, 2007. Retrieved on 2007-05-27.
External links
TC 105 IEC Technical standard for Fuel Cells
The Hydrogen Economy
BIGS: Fuel Cell Animation
The_ENV_Motorcycle at YouTube
EERE: Fuel Cell Types
EERE: Hydrogen, Fuel Cells and Infrastructure Technologies Program
How Stuff Works: Fuel Cells
LLNL: Direct Carbon Fuel Cell
LLNL: The Carbon/Air Fuel Cell Conversion of Coal-Derived Carbons
The 10th Grove Fuel Cell Symposium and Exhibition
Fuel Cells 2000
The US Fuel Cell Council
Ponaganset's Fuel Cell Education Initiative Classes
Fuel Cell Basics
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