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Old 25th November 2012, 19:10   #73
COLVERT
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R75 Saloon.

Join Date: Feb 2009
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Posting this here cos nobody really seems to know what chemical actions take place inside a charged battery as it starts to discharge. So here it is.

Basically lead to lead sulphate and acid to water. Follow the colour scheme. The two plates end up as lead sulphate when the battery is discharged. PbSO4.

When recharged the negative plate is pure lead. Pb. The positive plate becomes lead dioxide. PbO2.

The red ++ indicates two ions and the blue = indicates two electrons.

H2SO4 is the sulphuric acid.

H2O is the water.

Pb0 is lead oxide.

The battery is shown discharging. The direction of the chemical reactions is reversed on charging.

A battery must NEVER be left in a discharged state as the lead sulphate crystals on the two plates compact over a period of several months to a solid layer and kill the battery.

Charging and discharging keeps this sulphate layer to a minimum and increases the lifespan of the battery.



Colvert.

( Look after your battery and it will look after you. Lol )

PS. Click on thumbnail and have a study of it. The colours show how the chemicals combine and what compounds they form. The coloured arrows show the order in which the reactions take place.



Attached Images
File Type: jpg Battery chemical reactions.0001.jpg (135.9 KB, 753 views)

Last edited by Dragrad; 27th October 2013 at 00:37..
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