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Direct borohydride fuel cells (DBFCs) are a subcategory of alkaline fuel cells which are directly fed by sodium borohydride or potassium borohydride as a fuel and either air/oxygen〔Amendola S.C., Onnerud P., Kelly M., Petillo P., Sharp-Goldman S. L and Binder M. (1999) ‘A novel high power density borohydride-air cell’, J. Power Sources, 84, pp. 130–133.〕 or hydrogen peroxide〔Choudhury, N.A.; Raman, R.K.; Sampath, S.; Shukla, A.K. An alkaline direct borohydride fuel cell with hydrogen peroxide as oxidant. J. Power Sources 2005, 143, 1-8.〕 as the oxidant. DBFCs are relatively new types of fuel cells which are currently in the developmental stage and are attractive due to their high operating potential in relation to other type of fuel cells. ==Chemistry== Sodium borohydride could potentially be used in more conventional hydrogen fuel cell systems as a means of storing hydrogen. The hydrogen can be regenerated for a fuel cell by catalytic decomposition of the borohydride: :NaBH4 + 2H2O → NaBO2 + 4H2 Direct borohydride fuel cells decompose and oxidize the borohydride directly, side-stepping hydrogen production and even producing slightly higher energy yields:〔(Ma, Choudhury, Sahai - A comprehensive review of direct borohydride fuel cells )〕 :Cathode: 2O2 + 4H2O + 8e− → 8OH− (E0 = +0.4V) :Anode: NaBH4 + 8OH− → NaBO2 + 6H2O + 8e− (E0 = -1.24 V) ::Total E0 = +1.64V The simplified reaction is: :NaBH4 + 2O2 → NaBO2 + 2H2O + Electricity The working temperature of a direct sodium borohydride fuel cell is 70 °C (158 °F). 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「direct borohydride fuel cell」の詳細全文を読む スポンサード リンク
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