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charging a optima redtop


bheinen74
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I am attempting to chaarge my optima redtop that came with the 94ss builder. it arrived dead, the parking lights virgin switch on the dash had been on all the time the car sat at auction for who knows how long.

 

I had it on 2amp charge a day or more.

only got 7.5 volts on the dmm.

 

I read you need to charge it at 50amp or more.

so i have the charger set on start, and am cycling r in charge for 15mins then letting the battery cool off and cycling that.

 

any help maybe this battery is no good but i guess you have to force charge them.

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The trick to recharging a redtop is to use another battery with it.

Put the charger on a standard wetcell, then jumper cables to the redtop.

Charge overnight and it should be like new.

I used this technique with the redtop in my Brat and I can let it sit for days without draining.

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I've dealt with a couple dead gel-cell batteries and once they are discharged for a period it is unlikely they will come back. If it won't take a carge from an overnight stay on the 15 amp charger - it's unlikely to be salvageable. I have never brought one back from being that dead. I have had a lot more luck with regular liquid acid batteries. I often get them from the junk yard when I spot a good deal on a one that's fairly new.

 

GD

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it only read 7.5 volts after a day and half at 2amp.

i left it on the 50 amp boost for a few hours and it is to 8.0 but as soon as i put the dmm on it, the 8.0 just continually goes down.

 

I guess i will go drive it to the parts store and see what they will do. Its most likely more than 3 years old which it says 3 year free replacement. Now, if i get lucky, someone there will make me a deal trade or something. Too bad, so sad.

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Go ahead and throw away a perfectly good battery folks.

Mine is almost 2yrs old and I restored it.

 

Please read the following, its from Optimas own site.

 

Under normal vehicle starting applications, most regular automatic lead acid battery chargers will properly charge an OPTIMA. However, since OPTIMA batteries are frequently used in high-performance applications or non-standard vehicle starting applications, there are certain instances that must be given special considerations.

 

An OPTIMA battery is an AGM battery, not a "gel" battery or regular flooded acid battery. A deeply discharged OPTIMA battery (less than 10.5V) will not test or recharge properly if treated as a regular flooded battery or gel battery. A handheld electronic battery tester will most likely provide inaccurate test results.

 

An OPTIMA battery has the benefit of very low internal resistance, which allows high amperage output as well as efficient charge acceptance. This benefit also allows an OPTIMA battery to run longer than its specified ratings and run to a lower voltage than typical flooded batteries. All of this can lead to confusion when it comes to recharging a deeply discharged OPTIMA. Most basic battery chargers have a built-in function to prevent charging a battery with less than 10.5 volts. If your OPTIMA is discharged below that, the battery charger may not start up.

 

Most high-quality, modern battery chargers now have built-in features to charge AGM batteries like OPTIMA. Some have specific AGM settings which should be used to charge an OPTIMA. Do not use “gel” or “gel/AGM” settings, as they will not fully charge an OPTIMA and could damage it over time. However, even some AGM compatible chargers will not recharge deeply discharged (less than 10.5 volts) OPTIMA batteries. It may be necessary to follow the instructions provided in section #3.

 

For regular charging we recommend a maximum of 10 amps, 13.8-15.0V. For float charging, we recommend one amp maximum, 13.2-13.8V.

 

Under normal (engine starting) conditions, an OPTIMA battery should never experience “at rest” voltages below 10.5 volts. In these applications, most 12 volt chargers (old or newer) or alternators will sufficiently recharge an OPTIMA with at least 10.5 volts. Typically we only see issues with charging when it relates to stand-alone deep cycling applications or severely discharged OPTIMA’s.

 

http://www.optimabatteries.com/product_support/faqs.php

 

By using another battery in parallel, it fools the charger into thinking its charging a battery thats got 10.5v.

I also bolded a few things to point out some misconceptions.

More useful info from Batteries Are Us.

http://www.batteriesareus.com/index.php?main_page=page&id=2

 

I'll gladly take any redtops that you want to toss away.

Edited by Legacy777
Mod edited to change series to parallel
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Well - I don't have that problem with my battery charger - I have a 1950's 6-Amp unit that I use for charging up batteries that are very dead (it's slower and gentler than my modern 15-Amp unit). It doesn't have any issue with charging batteries that have virtually no voltage output. I have used it on a couple different spiral core units like the Optima's - sometimes it does work. But I've found some that just won't come back.

 

GD

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I have a small 120VAC/12VDC power supply from some electronic unit that I use for trickle-charging batteries. I have used it to charge motorcycle type batteries that you have to put the acid in when you buy them.

 

Maybe a simular unit would work on one of these.

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Having been an Optima dealer....

 

Use a second battery, but you put it in parallel, not series. Series would result in a (nominally) 24v system that your charger won't like anyway. Put put the charger on the dead battery and hang another battery off it.

 

Either way, check the date of manufacture on the label. They have something like a 3 year replacement warranty on them. If it is that dead, even if you bring it back, it'll never be particularly trustworthy. Warranty it if you can.

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so i use my good battery like this

charging_illustration.gif

 

 

can i use set of jumper cables to hook them together?

 

I "assume" this battery had to be good, since the car was running and driving before the front accident and then it went to auction site.

 

 

 

 

 

Like a ghost story, sometimes the seemingly dead really aren't dead at all. The same may be true for your over-discharged AGM battery.

 

In time, AGM batteries, including OPTIMA batteries, may fail. Failures are typically caused when a starting battery is used in a cycling application, in which a deep cycle battery is the better choice.

 

Okay, so now you have a seemingly bad AGM battery, you attach it to your charger and…CLICK. The charger won't even charge it! "It must be a bad battery!" you exclaim. Or is it? In many cases, OPTIMA batteries that are assumed to be bad may actually be perfectly fine, just deeply discharged.

 

The great thing about AGM batteries, including OPTIMA Red Top® and Yellow Top® batteries, is that they have incredibly low internal resistance. This allows very high amperage output and for the battery to accept a charge very quickly.

 

An AGM battery, with its low internal resistance, may stump car guys because sometimes it doesn't work like a traditional flooded lead acid battery.

 

Here's the problem: most battery chargers have built-in safety features. A traditional battery that's at 10.5 volts or less is seen as defective, having either a short, a bad cell or some other defect. The charger "knows better" than to charge a defective battery because the results could be unsafe. But the fact is the AGM battery is just fine; it has simply slipped below the minimum voltage threshold of the charger and the charger doesn't know what to do with the battery.

 

Here are three options for bringing that fine AGM battery back to life. So grab your jumper cables and charger and…CLEAR!

 

Recovery Option #1: The Best Solution – AGM-Specific Chargers

 

The best method for recharging a deeply discharged AGM battery is to purchase a modern charger that has kept up with battery technology. Many chargers now have AGM-specific settings and de-sulfation steps that help recondition and recover deeply discharged AGM batteries. These are becoming more common, and they work well for all lead acid batteries. They have the additional capability of doubling as a battery "maintainer" for vehicle storage. Some come with additional wiring to permanently attach leads from your battery to an accessible spot on your vehicle. This makes it easy to hook up when you store your car, truck, boat or RV.

 

OPTIMA Batteries does not officially endorse specific chargers—we simply don't have the time to test all of the excellent chargers on the market. There are a few that our customers and staff have tried and liked. You can contact OPTIMA Batteries Customer Service at 888-8-OPTIMA (888-867-8462) or via email at info@optimabatteries.com for charger recommendations based on different applications.

 

Recovery Option #2: The DIY Solution

 

This is a recovery method for the do-it-yourselfer using the equipment you've got in the garage. With this option, you're going to trick your charger into charging the deeply discharged AGM battery.

 

Here's what you need:

 

Battery charger

Jumper cables

A good battery, preferably above 12.2 volts (It can be an AGM or flooded battery, it doesn't matter.)

The seemingly dead, deeply discharged AGM battery

A watch or timer

Now, here's what you do:

 

Hook up the good battery and deeply discharged AGM battery in parallel—positive to positive and negative to negative. Do not have the charger connected to the battery or turned on at this stage.

Now, hook up the good battery to the charger. Turn on the charger. The charger will "see" the voltage of the good battery, and start providing a charge.

After the batteries have been hooked up for about an hour, check to see if the AGM battery is slightly warm or hot to the touch. Batteries naturally become warm during charging, but excessive heat may be an indication that there really is something wrong with the battery. Also discontinue the process if you hear the battery "gassing"—a hissing sound coming from the safety valves. If it's hot or gassing, STOP CHARGING IMMEDIATELY!

Check back every hour to see if the AGM battery has charged to 10.5 volts or above. If it has, disconnect the charger from the wall outlet and remove the good battery from the charger. Now, connect only the deeply discharged AGM battery to the charger. Turn on the charger and continue until the AGM battery reaches a full charge, or until the automatic charger completes the charge process. In most cases, the AGM battery will be recovered.

Recovery Option #3: Enlist the Professionals

 

If you don't own a battery charger, you don't want to make the investment, or you're not the do-it-yourself kind of guy, this is the option for you.

 

Take the battery to a professional battery specialist who knows AGM technology. Most specialists are willing to provide "charge and check" procedures free or for a small fee. Auto parts stores are typically not capable of accurately determining an AGM battery's condition, and many use conductance testers that don't provide correct readings. Battery specialists like Interstate Batteries and other independent battery distributors are experts who can help determine if your battery is recoverable or not.

 

 

 

 

I am working option 2 now.

i dont have a agm charger and neareset optima dealer etc is not close.

Edited by bheinen74
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Having been an Optima dealer....

 

Use a second battery, but you put it in parallel, not series. Series would result in a (nominally) 24v system that your charger won't like anyway. Put put the charger on the dead battery and hang another battery off it.

 

Either way, check the date of manufacture on the label. They have something like a 3 year replacement warranty on them. If it is that dead, even if you bring it back, it'll never be particularly trustworthy. Warranty it if you can.

 

Parallel is what I meant (fever from pneumonia fogs mind).

Brent, hook it up like you have in your diagram.

I used jumper cables doing mine, worked fine.

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Turbone, I changed your original post from series to parallel for clarification sakes for any newbies that may be searching in the future and not read the entire thread.

 

I've got two yellow tops, and my older one I had thought was dead, but I had another issue with a relay in the starter interlock circuit. Both the old yellow top & new one. I've read/been told comments that the yellow tops need a little more amperage to charge them fully. Not sure if that's true or not...

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Batteries are like any other electrical load. It doesn't matter how much amperage the source makes available, it will only draw so much current (amperage). Having said that, AGMs do tend to like a little more voltage than L-A batteries. Just don't push it much past 14.4v for very long.

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