大学化学 第四章-电池.ppt

1、Dry CellAnode oxidation:Zn(s)Zn2+(aq)+2e Cathode reduction:2MnO2(s)+2NH4+(aq)+2e Mn2O3(s)+2NH3(aq)+H2O(l)Overall reaction:Zn(s)+2MnO2(s)+2NH4+(aq)Zn2+(aq)+Mn2O3(s)+2NH3(aq)+H2O(l)BatteriesDry Cell and Alkaline BatteryMercury and Silver(Button)BatteriesAnode(oxidation):Zn(s)+2 OH-(aq)ZnO(s)+H2O(l)Cat

2、hode(reduction)(mercury):HgO(s)+H2O(l)+2 e-Hg(l)+2 OH-(aq)Cathode(reduction)(silver):Ag2O(s)+H2O(l)+2 e-2 Ag(s)+2 OH-(aq)Overall(cell)reaction(mercury):Zn(s)+HgO(s)ZnO(s)+Hg(l);Ecell=1.3 V Overall(cell)reaction(silver):Zn(s)+Ag2O(s)ZnO(s)+2 Ag(s);Ecell=1.6 VSecondary(Rechargeable)BatteriesLead-Acid

3、Batteries Anode(oxidation):Pb(s)+SO42-(aq)PbSO4(s)+2 e-Cathode(reduction):PbO2(s)+4 H+(aq)+SO42-(aq)+2 e-PbSO4(s)+2 H2O(l)Overall(cell)reaction(discharge):PbO2(s)+Pb(s)+2 H2SO4(aq)2 PbSO4(s)+2 H2O(l);Ecell=2 V Overall cell)reaction(recharge):2 PbSO4(s)+2 H2O(l)PbO2(s)+Pb(s)+2 H2SO4(aq)Automotive App

4、lication:the Discharge and Recharging of a Lead-Acid Battery Nickel-Cadmium(Nicad)BatteryAnode(oxidation):Cd(s)+2 OH-(aq)Cd(OH)2(s)+2 e-Cathode(reduction):2 NiO(OH)(s)+2 H2O(l)+2 e-2 Ni(OH)2(s)+2 OH-(aq)Overall(cell)reaction:Cd(s)+2 NiO(OH)(s)+2 H2O(l)2 Ni(OH)2(s)+Cd(OH)2(s)Ecell=1.4 VLithium Solid-

5、State BatteryAnode(oxidation):Li(s)Li+(in solid electrolyte)+e-Cathode(reduction):MnO2(s)+Li+e-LiMnO2(s)Overall(cell)reaction:Li(s)+MnO2(s)LiMnO2(s);Ecell=3 VSecondary(Rechargeable)BatteriesLithium-ion battery.Lithium Solid-State BatteryNickel-Cadmium(Nicad)Battery Flow Batteries(Fuel Cells)The Hydr

6、ogen Oxygen Fuel CellAnode(oxidation):H2(g)+CO32-(l)H2O(g)+CO2(g)+2 e-Cathode(reduction):1/2 O2(g)+CO2(g)+2 e-CO32-(l)Overall(cell)reaction:H2(g)+1/2 O2(g)H2O(g)Ecell=1.2 VOther Fuel Cells:2 NH3(g)+3/2 O2(g)N2(g)+3 H2O(l)N2H4(g)+O2(g)N2(g)+2 H2O(l)CH4(g)+2 O2(g)CO2(g)+2 H2O(l)Advanced Designs:Alumin

7、um-Air BatterySodium-Sulfur BatteryAnode(oxidation):4Al(s)+4 OH-(aq)Al(OH)4-(aq)+3 e-Cathode(reduction):3O2(g)+2 H2O(l)+4 e-4 OH-(aq)Overall(cell)reaction:4 Al(s)+3 O2(g)+6 H2O(l)+4 OH-(aq)4 Al(OH)4-(aq);Ecell=2.7 VAnode(oxidation):2 Na(l)2 Na+(l)+2 e-Cathode(reduction):n/8 S8(l)+2 e-nS 2-(l)Overall(cell)reaction:2 Na(l)+n/8 S8(l)Na2Sn(l);Ecell=2.1 VAdvanced Designs(Sodium-Sulfur Battery)