Club Car 1995 Golf Car, Дополнение к руководству по обслуживанию

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General Information Continued:
The batteries supplied with an electric vehicle must supply 100% of the energy required to move the vehicle.
These batteries therefore receive deep discharge down to 30% to 40% of their full charge capacity. Then they
must be recharged, hence their name “deep cycle.” The average amperage draw is considered to be 75 amps
on a 36 volt car, and 56 amps on a 48 volt car, although it varies greatly depending on the vehicle and how
it is operated. Golf car batteries are specifically designed to handle this type of service.
The rechargeable lead-acid battery is a device for turning chemical energy into electrical energy and vice
versa. The main active elements within a battery are the positive plates, the negative plates and the elec-
trolyte (sulfuric acid). Another very important element (but inactive) is the separator. The separator does
exactly what its name implies - it keeps the material of the positive and negative plates from touching each
other and creating electrical shorts. It must be porous enough to allow charged ions to pass through between
the positive and the negative plates, but never allow the two materials to contact each other.
Whenever two unlike metals are immersed in an acid solution, an electric current is generated.
In a “deep cycle” battery, the negative plates contain lead (Pb) and the positive plates contain lead dioxide
(PbO2). These plates are immersed in a sulfuric acid solution (H2SO4) (Figure 18-1).
During discharge, the chemical reaction inside the battery causes the sulfate (SO4) to break away from the
H2 (Figure 18-2).
The (SO4) combines with the lead (Pb) on both plates, forming lead sulphate (PbSO4). The oxygen (O2) from
the positive plates combines with the hydrogen (H) from the electrolyte to form water (H2O) (Figure 18-3).
The result is two similar metals, lead sulphate (PbSO4), immersed in water (H2O). This, of course, will not
generate electricity. This battery is discharged.
When a discharged battery is connected to a charger, the process is reversed. The sulfate (SO4) is forced
from the plates back into the electrolyte to make sulfuric acid (H2SO4). The oxygen returns to the positive
plate to make lead dioxide (PbO2) (Figure 18-4).
The result is a charged battery that is again capable of generating electricity (Figure 18-1).
In a deep cycle battery, the grids are heavy and the paste much denser to accommodate the deep cycle in
electric vehicle application. Some manufacturers have to use an even denser paste to avoid the shedding of
the paste, especially from the positive grid, that occurs to a greater or lesser extent in all batteries as they
age.
18-2
+
PbO2
Pb
H SO
2
4
CHARGED BATTERY
+
Pb
Pb
H
2
2
4
BATTERY IN USE (DISCHARGING)
SO
O
MOTOR
FIGURE 18-1 FIGURE 18-2