BATTERY CARE AND MAINTENANCE (CONT.)
BATTERY RATING
Batteries are rated at the current which will reduce
the voltage per cell to 1.67 volts in 20 hours. The
heavyweight battery has a 12 amp hour rating.
However its life at 100 watt continuous discharge
would be only 120 minutes. As the discharge
current is increased, the efficiency and relative
capacity decreases (
Fig. 6.1
).
BATTERY LIFE
Each time you cycle a battery it loses some of its
ability to take a charge. Deep cycle batteries are
capable of being charged and discharged from 100
up to 1,000 times, depending on the depth of the
discharge and the type of charger used. Service
life and shelf life are both adversely affected by
extreme temperatures.
BATTERY STORAGE
Batteries stored at room temperature will self-
discharge at 3% to 6% per month. Storage
temperature above 20°C (68°F) should be
avoided. Shelf life can be increased by storing in a
climate-controlled environment. Batteries should
be fully charged before storing and should be
recharged every four months.
EFFECTS OF TEMPERATURE
The temperature at which a battery is used also
affects the relative capacity of the battery. In cold
weather the shocking time will be less and the
battery will have less capacity (
Figs. 6.3 & 6.4
).
Life
Load
Capacity
20 hr
0.60A
12.0Ah
10 hr
1.05A
10.5Ah
5 hr
1.95A
9.7Ah
1 hr
7.20A
7.2Ah
30 min
12.00A
6.0Ah
15 min
20.00A
5.0Ah
Fig. 6.1:
Relative capacity of 12Ah
deep cycle battery.
Fig. 6.2:
Discharge curves for
12Ah and 7Ah batteries.
Fig. 6.3:
Effect of temperature
on battery life.
Fig. 6.4:
Effect of temperature
on capacity.
BATTERIES
LR-20 SERIES BACKPACK ELECTROFISHER
16
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