What is primary cell and secondary cell?

Battery which can be discharged only once is called primary cell ex: Manganese Zinc and alkaline

Secondary cells are the battery which can be charged and discharged for a number of times ex: Lead acid and Nickel cadmium.

Do temperature have effect on battery?

Temperature is one of the major factors that have impact on battery performance, shelf life, charging and battery voltage control. At higher temperature batteries will have more chemical activity compared to batteries which operate at the designed temperature.

What  factors that decide the VRLA battery to completely charged from fully discharged condition?

Some of the important factors that determine the duration of the discharged battery to charge are:

• Duration of the discharge occurred
• Temperature at which battery is operating
• Size and efficiency of the charger

Can VRLA batteries be enclosed in sealed containers?

VRLA batteries should not be enclosed in the sealed containers. Oxygen and hydrogen gases are produced in the battery, however they once again convert back to water. But during over charging these gases escape out of the cell. If the batteries are enclosed inside a sealed container, the pressure inside the container due to hydrogen and oxygen increases and may explode.

What is stratification in the battery?

During charging of the battery acid is produced at the plate surface and during discharging of the battery acid will be consumed, due to this nonuniform concentration heavy parts of the electrolyte settles at the bottom and lighter parts of the electrolyte floats on the top. This phenomenon is call stratification. Stratification affects the life of the battery.

What is end of life of the battery?

If a battery cannot able to hold proper charge or if the battery capacity is falls below 80% of its rated capacity then it is considered as the end of life of the battery. Many factors affect the life of the battery

• Charging and discharging cycles
• Temperature
• Leakage of the gases or electrolyte
• corrosion of the plates
• over discharge rates

How positive and negative terminals of a battery are identified?

Positive terminal is identified painted with red color and negative terminal is identified painted with blue color on the top of the battery.