Stupid question: do batteries come fully charged?

[dotorg]

I very deeply drained my battery in a failed attempt to put a kickin' stereo in my car a couple months ago, and realized having a 35 amp alternator just didn't cut it.

Anyway, since then it seems to charge poorly at best. It will charge as I drive, but if I wait a day to start the car, if it doesn't start on the first try, there's not enough juice for a second try.

So I bought an optima red-top at costco today.
Can I just drop a new battery in the car, or should I charge it first?

I know I can just measure the voltage, but I want to double check just in case.

[on-ramp]

i have the same problem with my 911T, i charge the battery , it starts fine...if i leave it for a few days, nothing! dead battery...

and the battery light stays on until about 3000 RPMs....recently rebuilt the alternator.

but to answer your initial question, yes, batteries come fully charged.

[camgrinder]

A 12 volt battery will read 12.6 volts if it is fully charged. Sometimes after charging it can read higher, but this is called a surface charge. After you put a load on the battery the surface charge goes away and it will read 12.6v.
Have someone hold the voltmeter accross the battery while you are cranking the engine.
If the voltage drops below 9 volts cranking
with the new battery you might have a starter circuit problem.

[Bob's Flat-Six]

If your battery won't start the car put it on a charger to bring it back up first instead of letting the alternator try to charge it.
You can also get a pretty good idea of it's condition by the charge it will take on the chargers gauge and how fast it takes a charge.

And yes they come with a charge but if your in dought or if it's been sitting awhile you could also put it on a charger to check it.
It should have a mfg. date on it so you can see how old it is too.

[singpilot]

Charged? yes.

Fully charged? no.

[dean]

Originally posted by singpilot
Charged? yes.

Fully charged? no.

Ditto