Fund of Electric Flashcards
What is meant by the capacity rating of a lead acid battery?
the number of hours a battery can supply a given current.
What electrolyte is used in a lead acid battery?
a mixture of sulfuric acid and water.
Does the Specific Gravity of the electrolyte in a lead acid battery increase or decrease as the battery is discharged?
It decreases.
What is the specific gravity in a lead acid battery?
Between 1.275 and 1.300
How many cells in a 24 volt lead acid battery?
12
How do you treat a lead acid battery compartment to protect it from corrosion?
paint it with an asphaltic paint or with a polyurethane enamel.
What is used to neutralize spilled electrolyte from a lead acid battery?
a solution of bicarbonate of soda and water.
How high should the electrolyte level be in a properly serviced lead acid battery?
only up to the level of the indicator in the cell.
Why is the closed circuit voltage of a lead acid battery lower than its open circuit voltage?
voltage is dropped across the internal resistance of the battery.
What gases are released when a lead acid battery is being charged?
Hydrogen and oxygen.
What is the electrolyte used in a nickel-cadmium battery?
Potassium hydroxide and water.
Is the electrolyte level of a nickel cadmium battery lowest when the battery is fully charged or fully discharged?
Fully Discharged.
What is a result of cell imbalance in a nickel cadmium battery?
the low internal resistance allows current to flow between the unbalanced cells and generate heat.
What is a thermal runaway?
Cells produce more heat then they can dissipate, the heat further lowers the internal resistance so more current can flow, this continues until the battery destroys itself.
How may thermal runaway be prevented?
By carefully monitoring the temperature of the cells and controlling the charging current to prevent an excess of current flowing into the battery.
