Page 77 - Electrician - TT (Volume 1)
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ELECTRICIAN - CITS




           •  K+ ions move towards +ve plate(anode)and reduce Ni(OH)4 to Ni(OH)2
           •  The OH ions move towards – ve plate (cathode) and oxides iron.
































           Positive plate
           Ni(OH)4 + 2K → Ni(OH)2  +  2KOH
           (nickel hydroxide)  (potassium)               (nickel of lower hydroxide)  (potassium hydroxide)
           Negative plate

           Fe + 2OH → Fe(OH)2
           (iron) (hydroxide of potassium) (ferrous hydroxide)
           During charging
           During  charging  the  current  flows  through  the  electrolyte  in  the  direction  from  the  positive  plate  to  negative
           plate. This current splits up the electrolyte in to potassium ions (k+) and hydroxide ions (OH-). The k+ ions move
           towards the negative plate and the OH- ions to the positive plate.

           •  K+ ions move towards  -ve plate  and OH- ions go to  +ve plate
           +VE PLATE :
           Ni(OH)2  +     2OH →  Ni(OH)4
           (nickel of lower hydroxide) (hydroxide of potassium) (nickel hydroxide)
           - VE PLATE :

           Fe(OH)2 +  2K →  Fe + 2KOH
           (ferrous hydroxide)  (potassium) (iron) (potassium hydroxide)
           The chemical action during charging and discharging can be summed up
           in a single equation.













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                                    CITS : Power - Electrician & Wireman - Lesson 13-19
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