Fundamental Physics/Electricity/Electricity Source/ElectroVoltaic

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Volta developed the voltaic cell about 1792, and presented his work March 20, 1800 . Volta ordered the metals in a 'tension series', “that is to say in an order such that any one in the list becomes positive when in contact with any one that succeeds, but negative by contact with any one that precedes it. Volta's law about opposing electrode emfs implies that, given ten electrodes (for example, zinc and nine other materials), 45 unique combinations of voltaic cells (10 × 9/2) can be created.

Batery's construction[edit]

Dry cell (PSF).png
EMF Cell chemistry Common name
Anode Solvent, electrolyte Cathode
1.2 V Cadmium Water, potassium hydroxide NiO(OH) nickel-cadmium
1.2 V Mischmetal (hydrogen absorbing) Water, potassium hydroxide Nickel nickel–metal hydride
1.5 V Zinc Water, ammonium or zinc chloride Carbon, manganese dioxide Zinc carbon
2.1 V Lead Water, sulfuric acid Lead dioxide Lead–acid
3.6 V to 3.7 V Graphite Organic solvent, Li salts LiCoO2 Lithium-ion
1.35 V Zinc Water, sodium or potassium hydroxide HgO Mercury cell


A typical symbolic convention in a schematic of this circuit


would have a long electrode 1 and a short electrode 2, to indicate that electrode 1 dominates.

See Also[edit]