Dead battery

**Mr Dark** · 04-08-05, 10:10 AM

When I went to bring the Corvette home for the summer, the battery didn't have enough power left to start the car (although a side issue, I don't understand this since I'd been starting the car every four weeks, without fail, since storing it).

I brought the battery home and hooked it up to a trickle charger. Does anybody have a formula which will let me estimate how long it will take to fully charge the battery? It's been on the charger for 16 hours now and it will be another 24 or so hours before I will be trying to start the car. Will the trickle charger bring it up to snuff in that time or do I need to put it on a more powerful charger?

Thanks for any thoughts/opinions!

**c4cruiser** · 04-08-05, 10:15 AM

A trickle charger will not bring the battery to a effective full charge. It would be best to take it to a shop where they can use a charger that will provide much higher amperage to the battery.

tnovot · 04-08-05, 08:05 PM

[QUOTE
I brought the battery home and hooked it up to a trickle charger. Does anybody have a formula which will let me estimate how long it will take to fully charge the battery? It's been on the charger for 16 hours now and it will be another 24 or so hours before I will be trying to start the car. Will the trickle charger bring it up to snuff in that time or do I need to put it on a more powerful charger?

Thanks for any thoughts/opinions!

[/QUOTE]

A one amp trickle charger will charge a motorcycle battery in about 8 hours so I would think that 16 hours on a trickle for a car battery would be plenty to get you started. I personally would not put it on a high amp fast charger especially after 16 hrs on a trickle charger.
I'm sure there is a formula but you would need to know what amperage your trickle charger puts out and what the battery capacity is. You might refer to the owners manual for the charger to get some guidelines. I don't think you need to get too technical.

herbha45@aol.com · 04-12-05, 07:09 PM

Charging a battery is all math. If you have a 600 amp battery that is dead and you use a 10 amp charger, it will take sixty hours, 10 divided into 600=60. Battery chargers are rated as AMP hours. If you use a 1 amp charger, your battery will be ready to go around Oct 05'! It is best to charge at a slow rate, say 5 amps if you can afford the time. Batteries should also stabilize for 8 hours after charger has been removed, this is according to BCI (battery council international.) This info. comes from me selling batteries for past 35 years. Good Luck hope this helps-96 Collectors Edition

**Mr Dark** · 04-13-05, 07:29 AM

Originally Posted by herbha45@aol.com

Charging a battery is all math. If you have a 600 amp battery that is dead and you use a 10 amp charger, it will take sixty hours, 10 divided into 600=60. Battery chargers are rated as AMP hours. If you use a 1 amp charger, your battery will be ready to go around Oct 05'! It is best to charge at a slow rate, say 5 amps if you can afford the time. Batteries should also stabilize for 8 hours after charger has been removed, this is according to BCI (battery council international.) This info. comes from me selling batteries for past 35 years. Good Luck hope this helps-96 Collectors Edition

I moved it from a trickle charger to a 10 amp charger and left it on for about 5 hours. The gauge on the charger dropped to under 2 amps, so I figured it was good to go. The car fired right up, so I'm hoping everything will work out. Thanks to all for the suggestions!

**WhalePirot** · 04-13-05, 11:16 AM

Understand that when a battery fully discharges, about 30% (I believe) of the capacity is permanently lost. You might want to carry jumper cables for a while. I'd be alert for power draining troubles; like what caused the 'dead'.

tnovot · 04-13-05, 01:22 PM

Originally Posted by WhalePirot

Understand that when a battery fully discharges, about 30% (I believe) of the capacity is permanently lost. You might want to carry jumper cables for a while. I'd be alert for power draining troubles; like what caused the 'dead'.

His '85 would have a digital dash. A caution might be in order about jump starting with the potential of causing damage to the Star Wars display.
I'm pretty sure that a voltage spike from a jump start is what zapped mine. There was at least one thread on this forum which discussed this but I didn't discover it until after the damage was done. All fixed now.
Terry

**WhalePirot** · 04-13-05, 01:54 PM

Originally Posted by tnovot

A caution might be in order about jump starting with the potential of causing damage to the Star Wars display.

This is true, and great advice. The caution is also listed in many late model cars' owners' manuals. The ECMs are also sensitive electronic units and subject to power spikes.

I am sorry to hear of your misfortune, but became quite good at jumping mine with the coninual Optima battery problems. I always alternated (+) and (-) connections and made the last connection to the (-) side of the other vehicle, usually the frame. I have never (knock on forehead) had problems with any of my electronics.

**Vanity Plate Bob** · 04-13-05, 02:58 PM

Does a battery that is 8 years old respond to charging as well as one that is 2 or 3?
Seems they do not.
If it is started every 4 weeks and 4 amps (or however many) are used and only run long enough to replace 2 a negative exists. Each time leaving less amps. Correct?
Old batteries or weaked celled ones fizzle out early.
Like old guys vs young ones running around a track. Usually.....