NP24-12BFR EnerSys, NP24-12BFR Datasheet - Page 12

• Manufacturer Part Number: NP24-12BFR
• Description: LEAD ACID BATTERY, 12V, 24AH
• Manufacturer: EnerSys

Specifications of NP24-12BFR

• Battery Capacity: 24Ah
• Battery Voltage: 12V
• Battery Technology: Lead Acid
• External Height: 125mm
• External Width: 175mm
• External Depth: 166mm
• Weight: 20lb
• Battery Terminals: Bolt
• Height: 4.92"
• Width: 6.54"
• Brand/series: NP Series
• Capacity: 24000 mAh
• Chemical System: Lead Acid
• Dimensions: 166mmL×175mmW×125mmH
• Primary Type: Rechargeable
• Resistance, Internal: 9.5 Milliohms
• Size: Rectangular
• Temperature, Operating: -15 to +50 °C
• Temperature, Operating, Maximum: +50 °C (Charge), +60 °C (Discharge)
• Temperature, Operating, Minimum: -15 °C (Charge), -20 °C (Discharge)
• Termination: Bolt Fastened
• Voltage, Nominal: 12 V
• Voltage, Rating: 12 V
• Lead Free Status / RoHS Status: na
• Lead Free Status / RoHS Status: na

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In actual use in indoor applications (5
104
temperature compensation function, but it is desirable to set
the voltage at the value shown in Figure 12 which
corresponds most closely to the average ambient temperature
of the battery during service.
When designing a charger equipped with temperature
compensation, the temperature sensor must sense only the
temperature of the battery. Therefore, consideration should
be given to isolating the battery and temperature sensor from
other heat generating components of a system.
■
The charging efficiency (η) of a battery is expressed by the
following formula:
Figure 12. Relationship Between Charging Voltage and Temperature
η=
Figure 13. Charging Efficiency vs. State of Charge
Charging Efficiency
0
F), it is not necessary to provide the charger with a
AH Delivered To The Battery During Charge
AH Discharged After Charged
0
C to 40
0
C or 41
0
F to
The charging efficiency varies depending upon the state of
charge of the battery, temperature, and charging rate. Figure
13 illustrates the concept of the state of charge and charging
efficiency. As shown in Figure 14, Genesis NP batteries
exhibit very high charging efficiency, even when charged at
low charging rates. It is interesting to note that the charging
efficiency of Genesis NP sealed lead-acid batteries is superior
to that of other batteries at relatively low charge rates
■
A battery is an indispensable component of any solar
powered system designed for demand-energy use. Since
solar cells have inherent constant voltage characteristics,
Genesis NP batteries can be charged directly from the solar
array using a simple diode regulated circuit as shown in
Figure15.
In designing a solar system, consideration should be given to
the fact that, in addition to normal periods of darkness,
weather conditions may be such that solar energy is limited,
or virtually unavailable for long periods of time. In extreme
cases, a system may have to operate for 10 to 20 days with
little or no power available for charging. Therefore, when
selecting the correct battery for a solar application, the
capacity should be determined based upon maximum load
conditions for the maximum period of time the system may
be expected to be without adequate solar input.
In many instances the battery capacity will be 10 to 50 times
greater than the maximum output of the solar panels. Under
these circumstances, the maximum output of the solar array
should be dedicated to charging the battery with no load-
sharing or intervening control devices of any kind.
Naturally, in cases where the output of the solar array exceeds
the capacity of the battery, and weather conditions are such
that the potential for overcharging the battery exists,
appropriate regulated charging circuitry between the solar
panels and the battery is recommended
Figure 14. Charging Efficiency
Solar Powered Chargers
Publication No: US-NP-AM-002 • June 2006
.
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