Automotive - Batteries
What is the maximum temperature a battery should be allowed to reach when charging?
52 Degrees Celsius
The chemical action of a lead acid battery cell during discharge can be described as?
The electrolyte combined with the active material of the plates forming lead sulphate whilst the electrolyte becomes weaker.
A feature of semi-maintenance free automotive battery's are?
They require maintenance less frequently than some other automotive batteries.
What is the purpose of a load tester?
To determine the battery's ability to supply cranking current.
Checking the electrolyte temperature and level when charging is important. Why?
To ensure that the battery doesn't get too hot and so the electrolyte level doesn't over flow.
How do you connect computer safe jumper leads?
1. Connect the red jumper lead to the positive terminal of the dead battery. 2. Connect the other end of the red jumper lead to the positive terminal of the good battery. 3. Connect the black jumper lead to the negative terminal of the good battery. 4. Connect the other end of the jumper lead to a good earth point away from the dead battery.
How do you discontent computer safe jumper leads?
1. Disconnect the slave battery negative jumper lead. 2. Disconnect the flat battery negative jumper lead. 3. Disconnect the flat battery positive jumper lead. 4. Disconnect the slave battery positive jumper lead.
What dose battery maintenance typically involve?
1. Checking the electrolyte level. 2. Cleaning the battery terminals. 3. Cleaning the battery top. 4. Checking the battery tray and hold down clamp. 5. Inspecting the battery for physical damage.
12v automotive lead acid battery is faulty, it is said to be "Sulphated". What would be the operating characteristics of a battery with this fault?
1. Reduced open circuit voltage. 2. Reduced charge and discharge ability. 3. Decreased discharged voltage when under load.
What is the main purpose of an automotive battery?
1. When the vehicle is not running the battery supplies electrical energy to operate the lighting systems, and other electrical accessories. 2. When the engine is starting the battery operates the starter and provides current for the ignition system, charging system and fuel system. 3. When the engine is running the battery may be needed to supplement the charging system when the vehicle load exceeds the charging systems output.
What is the electrolyte gravity of a battery that is 25% charged?
1.175
What is the electrolyte gravity of a battery that is 50% charged?
1.200
What is the electrolyte gravity of a battery that is 75% charged?
1.230
What is the electrolyte gravity of a battery that is 95% charged?
1.250
What is the electrolyte gravity of a battery that is 100% charged?
1.265
What should the specific gravity of the electrolyte be in a fully charged 12v battery at 16 degrees Celsius.
1.280
You are testing a car battery with a high rate discharge tester, the battery has a rating of 200 CCA. What will you set the tester to?
100amps
What is the voltage of a battery used in a car?
12v
The normal voltage supplied by a single cell of a lead acid battery when fully charged is?
2.1v
A 6 volt lead acid battery has how many cells?
3
A low electrolyte level, with no evidence of a container leak, can indicate what?
A high charging rate or faulty cells.
The amp-hour rating of an automotive battery relates to what?
Ability to provide a number of amps (at a ten hour rate) before it is discharged.
The CCA rating of an automotive battery relates to what?
Ability to provide a number of amps to crank the engine at -18 Degrees Celsius.
What forms the basis for calculating a vehicles battery charge rate?
Ampere-hours at a specified hour rate.
The term "fast charging" refers to what?
Charging the battery at 40 to 60 amps for a very short time period.
The term "trickle charging" when charging a battery refers to what?
Charging the battery on and off for at least 12 hours.
Name three things that must be checked when fitting a replacement battery.
Check the polarity of the battery for correct fitting, the earth lead is removed first and check that the battery tray is in a good, clean state.
What type of current do automotive batteries produce?
Direct current
A battery having a voltage of 11.8 Volts with a nominal load applied is regarded as?
Discharged
What is the chemical action of the cells when the battery is charging?
Electrical energy from the charger is converted into chemical energy.
What are the two types of terminals on a battery?
Flat and round terminals.
What gas is produced from the cell when charging a lead acid battery?
Hydrogen gas
Name three methods of determining a battery's capacity.
Hydrometer, high rate discharge test and using a battery analyser.
An increase in battery temperature will cause the specific gravity of battery electrolyte to?
Increase
The electrolyte of a 12v automotive battery is?
Is a mixture of sulphuric acid and distilled water and can be a gel or a liquid.
What dose the following relate to, when regarding basic automotive batteries? Battery used for extra electric power
Jump starter power pack.
What dose the following relate to, when regarding basic automotive batteries? The battery is a voltage stabiliser
Keeps the voltage at a constant rate.
What is the active material used on positive plates of the battery during charging?
Lead peroxide
What is the voltage of a battery in a hybrid vehicle?
Many 1.2v nickel batteries connected in a series to give a total of 200v.
What is the purpose of the cover on a lead acid battery?
Seals the top of the battery to prevent dirt and foreign objects entering inside.
The term "open circuit" when testing a battery refers to what?
No external load applied.
A battery will become flat or at least have less energy than a fully charged battery when not used (stored) for a long period of time. What is this called?
Self-discharge
The plates within a 12v lead acid battery are?
Six plates of lead with a separator between each plate and can produce a maximum of 12.4v.
What is the case of a lead acid battery made of?
Strong plastic or rubber to withstand the corrosive nature of the battery contents.
A deep cycle battery is one that is?
Suited to be discharged more deeply and then re-charged.
The service life of an automotive battery can be expressed as?
The approximate number of charge and discharge cycles that a battery will preform within its life span.
The chemical action of a lead acid battery cell during charging can be described as?
The chemical action causes the plates to reform back into lead peroxide and the acid to reform back into the electrolyte.
What is the chemical action of the cells when the battery is discharging?
The chemical energy is converted into electrical energy.
A feature of a sealed low maintenance automotive battery is?
They do not require electrolyte to be topped up.
What is the purpose of an Electronic Battery Protecter?
To save data on any faults that might have occurred during testing and/or contain the full data to operate the vehicle.
What is the function of battery isolators?
To stop the supply of power to the rest of the vehicle.
What dose the following relate to, when regarding basic automotive batteries? Heavy duty battery
Trucks/heavy vehicles
What is the voltage of a battery used in a large vehicle?
Two large 12v lead acid batteries connected in series to give 24v output.
