A battery is nothing more than a storage device for electric power. The alternator changes the kinetic energy given off by the engine into electrical energy. If the battery can be charged and store energy but the battery keeps discharging after you use the vehicle, check the alternator. If someone accidentally reversed polarity EVEN BRIEFLY while jump-starting the vehicle the diode plate is probably destroyed and you will have to replace or repair the alternator.
either the alternator is dischargeing the battery or it is going flat just because its not getting re charged
Not likely, but running the engine with a dead battery can damage some alternators. Always fully charge the battery when installing an alternator.
I assume you mean how long to charge the battery. You should never let the alternator charge a dead battery if possible. The alternator is designed to keep the battery charged but not to charge a dead battery. You put a strain on the alternator and it can cause a diode to burn out. Drive home and then put a battery charger on the battery to fully charge it.
An alternator is designed to keep a fully charged battery at peak level. It is not designed to charge a dead battery. Installing a new alternator on a car with a dead battery can in some cases ruin the new alternator. Fully charge the dead battery before starting the engine.
Yes, it can ruin the battery by overcharging it. If you are reading between 13.5 to 15.5 volts at the battery with the engine idling then more than likely the alternator is good and you battery has a dead cell. A fully charged battery will read 12.6 volts with the engine not running.
New batteries almost always come fully charged. If it was not then charge it with a battery charger and do not use your vehicle alternator to charge a dead battery. You may do harm to the alternator which is not built to charge a dead battery but is instead built to keep a good battery fully charged.
My advice is to charge the battery with a battery charger before starting the engine. You will be putting a heavy load on the alternator if you allow it to charge a dead battery. This could damage the alternator.
That is the purpose of an alternator. The keep the battery charged and to run all the electrics on the vehicle. However it is never a good idea to allow the alternator to charge a dead battery. This will put a strain on the alternator and may damage it.
Defective alternator, dead cell in battery, something on pulling power from the battery when the vehicle is idle, corroded battery cable connections, or loose alternator drive belt.
Dead battery, car will not start
Yes, alternators are designed to maintain the battery, or recharge a battery that has been slightly discharged from starting the car. When the alternator is used to recharge a dead battery, it causes the alternator work harder and longer than it is designed for, causing it to overheat, thus causing damage to the alternator. A battery charger should be used instead. They are designed for charging dead batteries. After the battery is charged, let the alternator maintain the charge.
Yes, once you have jump started the car (from another car's battery), driving the car will recharge the dead battery (provided the battery is OK). This is a terrible idea and may damage the alternator. Drive the car immediately home and charge the battery with a battery charger. Alternators are designed to keep a charged battery fully charged. They are not designed to charge a dead battery. This puts way too much strain on the alternator circuits.