Quick question.

Situation:

The battery in my car is about a year old and since I don't drive my car that often, the battery often runs all of the way down over time. I have had to charge it on a few occasions.

Most recently I left an interior light on in my car for a few days and ended up with a dead battery. I charged it overnight and in the morning had a fully charged battery. It reads 12V when tested, however it will barely turn the starter to start the car. I am only able to start the car with the help of my battery charger.

Question:

Is it volts or amps that are required to turn a starter quick enough to start the car? Could I have a battery that is fully charged from a volt stand point and not an amp standpoint?

 

Its the amperes (amps). You can go to radioshack and by a 12volt battery for a cordless phone, but it won't do anything in a car because the amps are low. Car batteries have anywhere around 525 amps and up. I have 2 batteries for my Ford Explorer (1000amps) so I put 1 in my car. It turns the starter over mad qwik y0!!!1!1

 

unlike a nickle-cadmium (ni-cad) battery, the lead-acid batteries in our cars don't like to be discharged all the way, that's probably most of your problems...volts and amps are proportional to each other, each is as important as the other when talking about power required to turn the starter...if you increase the voltage, you decrease the amps, but the same amount of work is done...make any sense?

 

Thanks for the explainations. So is it possible to have the battery show a full charge on my battery charger (12V) and not have the amperes to turn the starter quickly enough to start the car?

 

Yes.

My old battery did not have enough current to engage the starter, but still showed fully charged on my charger.

 

Bad battery. Put the meter on the battery. Turn the key to Start while watching the voltage on the meter. I bet it falls below three volts. I=E/R or I=V/R.....thank you Mr. Wilson, 10 grade physics teacher, I believe. (humor, NOT a slam).

 

On mine, as soon as the key was turned to start, the voltage dropped off the guage.

 

Thanks guys. Looks like I will be returning the battery then.