separators may become filled
with sulphate or impurities, and thus prevent the proper circulation
of the electrolyte. New separators must be put in.

6. Shedding. The capacity of a battery naturally decreases as the
active material falls from the plates, since the amount of active
material which can take part in the chemical actions that enable us to
draw current from the battery decreases.

7. Low Level of Electrolyte. Aside from the loss of capacity which
results from the sulphation caused by low electrolyte, there is a loss
of capacity caused by the decrease in the useful plate area when the
electrolyte is below the tops of the plates. Only that part of the
plate surface which is below the electrolyte does any work, and the
area of this part gradually decreases as the electrolyte falls.

8. Reversal of Plates. If one cell of a battery has an internal short
circuit, or some other defect which causes it to lose its charge, the
cell will be discharged before the others which are in series with it,
and when this cell is completely discharged, the other cells will send
a current through it in a discharge direction, and the negative plates
will have a coating of lead peroxide formed on them, and will assume
the characteristics of positive plates. The positives will be reversed
also.

This reversal may also be the result of charging a battery in the
wrong direction, on account of reversed charging connections. The
remedy for reversed plates, provided they have not become
disintegrated, is to give them a long charge in the right direction at
a low rate.

9. Effect of Age. A battery gradually loses capacity due to its age.
This effect is independent of the loss of capacity due to the other
causes. In the negatives, the size of the grain increases its size,
giving the plates a granulated appearance. Stitch plates are called
"granulated" negatives. The spongy lead cements together and loses
porosity.

Loss of Charge in An Idle Battery

It has been found that if a charged battery is allowed to stand idle,
and is not charged, and no current is drawn from it, the battery will
gradually become completely discharged and must be given an occasional
"freshening" charge.

Now, as we have learned, when a battery discharges lead sulphate forms
on each plate, and acid is taken from the electrolyte as the sulphate
forms. In our idle battery, therefore, such actions must be taking
place. The only difference in this case is th