Severe discharge means using electricity from battery while a vehicle engine is
not started.
For example, listening to the radio, watching TV or operating electric devices
such as constant power supply for black boxes.
That is, only discharging condition. The sulphate generated at this time attaches
to the pole plates and does not comes off.
If this condition continues, sulphate attaches to the whole surface of pole
plates, leaving no places for the anion and cation, which are generated from
electrolysis, to attach, and the action to change electric energy to chemical
energy cannot be performed. It means that the action to change chemical
energy to electric energy also cannot be performed. That is, the life of a battery
ends.
If a battery is not in a good condition, much load is given to alternator
(charger) at the first time. For instance, when we say that a battery is a bowl
and that the battery current is water (current) in the bowl, alternator needs to
fill more water into the bowl when the water (current) in the bowl is a little.
And it forms a hindrance to smooth power supply to other devices that need