Electrochemical Voltage Series; Excerpt From Electrochemical Voltage Series - Volkswagen Passat ‘97 User Manual

Electrochemical voltage series

In the presence of water, an electric current
develops between two different metals. The
car battery operates according to a similar
principle.
The electric current causes one of the two
metals to decompose. If a metal decomposes
easily, it is termed a non-precious metal. If a
metal does not decompose easily, it is termed
a precious metal.

Excerpt from electrochemical voltage series

H O
2
Magnesium
An electrochemical voltage series is produced
by arranging the metals in a series extending
from non-precious metal to precious metal.
The further the metals in the voltage series are
apart from one another, the higher the current
and the more readily the less precious metals
decompose.
Aluminium Iron
Al Fe
Lead Copper
Pb Cu
SSP 192/096
Gold
Au
37