Does a battery lose voltage as it discharges?
Voltage Changes During Discharge. At the end of a charge, and before opening the charging circuit, the voltage of each cell is about 2.5 to 2.7 volts. As soon as the charging circuit is opened, the cell voltage drops rapidly to about 2.1 volts, within three or four minutes.
What to do when your car battery dies?
If the battery dies after some driving and can sit relatively ok, your alternator/charging system is malfunctioning. Do this, get a battery charger for your car, charge the battery, and when it’s done measure/record the voltage when the battery is disconnected from the car and connected to the car.
What causes the voltage to drop on a new battery?
On a new battery, this can be a result of manufacturing flaws, but it also may be caused by sulfate crystal buildup. Under the intense heat of the load, one or more of the weld pieces connecting the cells is coming loose and separating. This will cut the current, and voltage will drop.
Why does my car battery die after sitting for a long time?
If the battery is dieing from just SITTING, you likely have a short somewhere. If the battery dies after some driving and can sit relatively ok, your alternator/charging system is malfunctioning.
What should the voltage be on a DC alternator?
Thirdly, once the battery is charged, the voltmeter (read the instructions how to check voltage with DC volts) should read between 12 and 13 volts across the battery posts while it is running. This indicates the alternator is functioning. If you shut it off it should be just about 12 volts.
When does a 12V battery go dead?
The actual dead level is determined by the circuit, when it stops working the battery is flat. A battery is properly dead when is drops below a recoverable (pre-determined) minimum level. So, it depends. Hi, . . Usually 10.5V or so, is considered a flat 12V battery. . .
On a new battery, this can be a result of manufacturing flaws, but it also may be caused by sulfate crystal buildup. Under the intense heat of the load, one or more of the weld pieces connecting the cells is coming loose and separating. This will cut the current, and voltage will drop.
If the battery dies after some driving and can sit relatively ok, your alternator/charging system is malfunctioning. Do this, get a battery charger for your car, charge the battery, and when it’s done measure/record the voltage when the battery is disconnected from the car and connected to the car.
How is the dead level of a battery determined?
The actual dead level is determined by the circuit, when it stops working the battery is flat. A battery is properly dead when is drops below a recoverable (pre-determined) minimum level. So, it depends.