Komatsu 830E-AC Shop Manual page 237

To offset the results of self-discharge, booster-charge
idle batteries (not a quick charge) at least once every
thirty days. Batteries not used for long periods in a
discharged condition are attacked by a crystallization
of the lead sulfate on the plates. Such batteries are
called sulfated and are, in the majority of cases,
irreparably damaged. In less severe cases, the sul-
fated battery may be restored to limited service by
prolonged charging at a low rate (approximately 1/2
normal rate).
Freezing
An undercharged battery is extremely susceptible to
freezing when stored in cold weather.
The electrolyte of a battery in various stages of
charge will start to freeze at temperatures indicated
in Table 10-1.
The temperatures in Table 10-1 indicate the points at
which the first ice crystals appear. Lower tempera-
tures must be reached for a solid freeze. Solid freez-
ing of the electrolyte may crack the battery case and
damage the positive plates. A battery with at least a
75% charge is in no danger of freezing, especially
during winter weather.
Table 10-1: OPERATING TEMPERATURES
Specific Gravity
Corrected to 27°C
(80°F)
1.280
1.250
1.200
1.150
1.100
NOTE: If the temperature of the electrolyte is not rea-
sonably close to 27°C (80°F) when the specific grav-
ity is taken, adjust the temperature factor to 27°C
(80°F).
D10003 07/06
Freezing
Temperature
Degrees
-70°C (-90°F)
-54°C (-60°F)
-27°C (-16°F)
-15°C (+5°F)
-7°C (+19°F)
Battery Charging Alternator D10-7