Discharge

The curves shown in Figure 2 and Figure 3 and the discharge rates shown in Table 4 and Table 6 illustrate the typical discharge characteristics of Yuasa NP batteries at an ambient temperature of 20°. The symbol "C" expresses the nominal capacity of the battery measured at a 20-Hour discharge rate. Please refer to General Specifications on page 3 to determine the nominal capacity rating of specific NP models. The standard industry practice to determine the nominal capacity of a valve regulated lead acid battery is to discharge the battery under test at its 20-Hour rate to a final voltage of 1.75 volts per cell.

The curves in Figure 3 show the different currents that can be drawn at various discharge capacity rates at an ambient temperature of 20°C.

Table 4 and Table 7 show that the rated nominal capacity of a battery is reduced when it is discharged at a value of current that exceeds its 20-Hour discharge rate. This should be taken into consideration when a battery is being selected for a particular application.

Fig.3 NP Discharge Characteristic Curves at 25°C (77°F)

If a battery is to be discharged at a rate in excess of 3C Amps, please consult us prior to use.

Temperature Characteristics

At higher temperatures, the electrical (Ah) capacity of a battery increases and conversely at lower temperatures, the electrical (Ah) capacity of a battery decreases. Figure 4 shows the effects of different temperatures in relation to battery capacity.

Fig. 4. Temperature Effects in Relation to Battery Capacity