C&D Technologies RS-2061 Standby Batteries for Renewable Energy Applications User Manual

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Charging Voltage Temperature Compensation Chart

Electrolyte Freezing
To prevent freezing make be sure maintain a high state of charge and thus a high specific gravity in the bat-

tery. The following graph gives the freezing point of the electrolyte at different specific gravities.

Testing
Batteries are rated on an ampere-hour basis or on their ability to deliver a certain number of amperes to the

load for a specified amount of time before cell voltages drop to a given potential. It is important to realize that

the ampere-hour capacity of a cell or battery depends on the rate at which it is discharged.

The C&D Technologies lead acid battery and cells are designed for optimum discharge characteristics of

long rate discharge. This permits batteries to discharge to lower end-potentials of 1.90 volts per cell. It is

also important to consider low ambient operating temperatures when calculating required battery size.

Low operating temperatures will reduce available battery capacity significantly.

To be valid, a capacity test must assume the following:
•

A fully charged battery and balanced cell potentials. In some cases, this may require an equalize

charge or, in cases of sulfation, other action. Consult the C&D Technologies Technical Services

Department.

•

All cells equalized to their nominal specific gravity. This may require addition or withdrawal of acid

and should only be done following a complete recharge and equalizing charge.

•

At least 72 hours on nominal system voltage. This is especially important following an equalize charge,

to clear excessive gasses developed at the surface of the plates by letting the battery rest off charge or

on float charge.

•

Temperature correction for cells tested at any temperature other than 77°F (25°C).

•

Batteries are fully charged and all connections are correct.

CPV Models

VR Solar

D, K, L - CPS

+ 2.8 mV/F per cell below 77°F (25°C)

- 2.8 mV/F per cell above 77°F (25°C)

+ 3.0 mV/F per cell below 77°F (25°C)

- 3.0 mV/F per cell above 77°F (25°C)

+ 2.8 mV/F per cell below 77°F (25°C)

- 2.8 mV/F per cell above 77°F (25°C)

Battery Series

Temperature Compensation

RS02061/0514/CD