UPDATE:

I placed the battery tender back on the battery for a couple of days while I was out of town. I started the car this morning and it fired right up. I will take the charger off the battery measure the current draw and let it sit to see if it repeats this process.

Any other ideas, or should I yank the battery and replace it?

 

All battery's should be charged first, you never know how long they were sitting.

My last battery in my Windstar had a 75% charge when I bought it, 3 years later and it is still working perfect.

 

Buy the correct Ctek charger for it.

 

I bought a red top for my car in November of 2002. I have never done anything to it over the course of ownership, including using a battery tender..it would sit over the winter, and start right up.. never needed a charge, or a jump... Last fall I bought a battery tender, and when I put the car away, I hooked it up...Ive driven the car a few times over the winter and it never failed to start... The battery tender has been off the car since february, and I drive the car three or four times a week, and it never seems to be a problem... I believe there are problems with Optima Batteries, but its a good company and they should have any issues solved, I know I got a good one, or possibly some people have unregulated battery tenders and its the tender that is causing the problem... MY Battery never saw a battery tender until this year.. This is just my experience.

 

I had a Delco 75-7YR premium battery in my 2001 Coup. It just died so I dropped the big bucks and bought another one. The first one gave me many years of trouble free driving with no battery tenders and always started after extended periods of storage. Based on that I thought what the heck, I'll go with what has worked well for me in the past.

 

Been through 3 of them in the past 3 years.. My car is driven on the weekends and raced occasionally.. After 2 week it will BARELY turn over to start..

Good news.. They hava a killer warranty and I just bring em back to Autozone and I walk out with another..

Warranty starts all over...

 

The way I'm reading the charging specs is that once the charger is in "float charge" mode, Optima says "1 amp maximum current".

As long as the battery charger doesn't over heat the battery, and puts out more than 1 amp in the main charging mode, then it should work just fine. I know for a fact that using a Battery Tender does NOT put out anywhere near high enough current to heat up the battery.

According to the specs, a Battery Tender puts out 1.25 amps. I've used one on my Red Top for years and it seems to charge it just fine, and the battery has been strong with no abnormal voltage loss from sitting for a month at a time. Obviously, you don't want to put a "trickle charger" on it that puts out less than 1 amp.

For those of you who use a Battery Tender Plus & Junior, here is their statement on AMG type of batteries.

"INFORMATION NOTE ABOUT DRY-CELL BATTERIES:
There are some wet, non-spillable, lead acid batteries on the market whose
manufacturers' make the claim that they are dry-cell batteries. These batteries
are sealed, gas-recombinant, starved electrolyte, possibly with AGM
(Absorbed Glass Mat) type construction. It is perfectly safe to use Battery
Tender® Junior and Plus Chargers to charge these types of batteries. The
dry-cell battery warning is intended for rechargeable or non-rechargeable
alkaline and other similar types of batteries. If you have any doubt about the
type of battery that you have, please contact the battery manufacturer before
attempting to charge the battery."

Link to Battery Tender's website, and more manufactures specs/instruction info links there.
http://batterytender.com/product_info.php?products_id=2

 

I guess I'm a little confused on the write-up above. First, they say it puts out 1.0 A maximum ... then they say it puts out 11.0 A maximum.

Is that 11.0 a typo, and should really be 1.0 A ??

Even if it was 1.0 A maximum, isn't this slightly out of bed with the previous Optima Charging Specs that indicates you should probably need slightly more than 1.0 A to bring it to full charge? Hummm ... slight inconsistency IMO. I guess it could be interpreted as 1.0 amp or more will do the job. Like I said above, the Battery Tender Plus puts out 1.25 A, so IMO that's great.

 

Hi, I think you are reading the instructions correctly, as they say "when battery is full and charger is in float mode it should be 1 amp max. But if the maintainers circuitry is not set for a 1 amp pulse mode and is kicking in and out with a 1.25 amp charge when it feel the battery is needing it, that is not the optimum situation for Optima designs. The optima being a newer design than some of these older maintainers were designed for, needs slightly different circuitry engineering, which some of the newer maintainers have. Whether or not to believe the maintainer manufacturers statements as to their products ability to do the job remains to be tested. And it is through forum discussions like this that tell the real story. If a good percentage of people with ther Optima /Battery Tender combination are having a problem, then something is wrong with either the Optima quality, or the Tenders design for that application.
Good Luck

 

Hi, Yes you are correct, 11 amps would not be what an optima would enjoy. I'm not sure what that statement means myself. But the excerpt comes from a write up on a specific model Batteryminder that is intended for only AGM type batteries. See Below..
++++++++++++++++++++++++++++++++++
AGM/Optima BatteryMINDer PLUS®
[12118] $54.95



Click to enlarge

Model 12118
AGM/Optima 12 Volt 1 Amp BatteryMINDer PLUS®
Maintenance Charger/Desulphator Conditioner


This specially adjusted BatteryMINDer PLUS® is designed to maintain Optima, Odyssey and all known brands of AGM sealed "dry" batteries at full charge, without ever overcharging. Special adjustment ensures complete compliance with battery manufacturer's exact specifications for cyclic long term non-use storage. One (1) Amp (constant voltage) maximum current, when battery is at less than full charge when first stored, complies with AGM battery maker's requirements.

The AGM/Optima BatteryMINDer PLUS® goes two steps further than any known maintenance charger. Using Pulse Width Modulated (PWM) circuitry the unit supplies each battery with just the amount of current needed to raise or maintain the battery's voltage at full charge level. Second step is the full-time automatic process that safely removes harmful sulphation. By using U.S. patented pulse mode technology it dissolves the crystals of sulphate that prevents the battery from delivering its full power and cycle life. It does this without raising the output voltage above the battery maker's maximum recommended voltage levels. Keeping the battery free of sulphate virtually guarantees to significantly increase your battery's life and performance. All units are individually adjusted to ensure compliance with each battery manufacturer's specifications.

VDC Electronics guarantees a sulphate-free battery over its entire life-time or you will receive 100% of your money back. This guarantee is in addition to a five (5) year "no hassle" warranty.

NOTE: Model 12118 AGM/OPTIMA BatteryMINDer PLUS® should only be used on AGM type sealed batteries, not "filler cap" liquid batteries, due to its special voltage settings. This unit is designed primarily as a maintenance charger for long term, safe storage charging of Optima and other similar AGM type batteries, not as a primary or general charging source.

Additional Features

Safely maintains and desulphates all size/type/brand starter, deep cycle, dual purpose sealed, AGM, Optima, "dry"-type batteries in accordance with battery manufacturers specifications.
Maintains from 1 to 5 batteries at a time (12 Volt batteries parallel-connected or 6 Volt batteries series-connected) for less than 15 cents per month.
Guaranteed to never overcharge any battery, regardless of how long connected.
Full-Time Desulphation automatically dissolves harmful sulphate when unit is in either the charge or maintenance modes, using safe U.S. Patented pulse technology.
Isolation transformer and smart chip technology ensure safe, long-term performance.
Auto reset thermostat - prevents damage to charger when connected to faulty battery.
Full-time battery monitoring - automatically tests battery every microsecond, supplying only the current needed to maintain battery at full charge.
Weatherproof - conformal-coated circuitry ensures trouble-free life even in high-moisture marine environments.
Allows battery to be stored safely at 0° to +120°F.
Unit comes complete with Qwik connect/disconnect battery clips and a ring terminal assembly (with easily replaceable fuse) for permanent connection.
Full year 100% money-back guarantee takes the risk out of trying this product.
Five (5) year "No Hassle" warranty covers everything except physical abuse.
++++++++++++++++++++++++++++++++++
I beleive it is noteworthy that Batteryminder specifically limits a model to AGM type batteries. Which would lead me to beleive that quite a few other maintainers, specified for ALL types are compromises at best, and are not capable of maintaining an AGM properly. I also beleive that the desulphating pulse technology is very important for an AGM type as well as not overheating it. One other point, I've seen numerous posts about people using their cars in VERY hot climates, south, and southwest. And the consensus seems to point to the overheating problems of an AGM, as many state that they have had Optima types and have had them fail in a relatively short time period, compared to other types.
Luck To ALL.

 

See FAQ #5 and #13 in the link below. Battery Tender specifically say that the "Battery Tender Plus" and the Battery Tender Junior" are designed for AGM type of batteries.

http://batterytender.com/faqs.php

Their "Selection Guide" also has info that shows they are compatible for AGM batteries.

http://batterytender.com/selection_guide.php

Chances are, if someone is having issues with an Optima battery when using a Battery Tender Plus, then it’s probably the battery going bad. Like I said earlier, I’ve used a Battery Tender Plus for 3 years on my Optima Red Top over the winter months and it the battery doesn’t self-discharge any more then it did the day I put it in when new.

 

I am on my second Red Top in two years, I got the second on warranty from Advance Auto. Call me vain, but the only reason I went back to the Red Top is because it matches my engine, I dont think it is the best battery out there. Since I got the second battery, I am out of town for long periods of time so I just disconnect the battery. When I need to use the car, I just reconnect the battery and it seems to fire right up. Am I hurting the battery by not tickle charging it with a battery tender?

 

Hi, in answer to the question , "Am I hurting the battery by not tickle charging it with a battery tender?", my opinion based on the companies own suggestions is that you are probably shortening it's useful lifespan. Optima's like all batteries need to be maintained at their full charge to last their full intended service period. And if you are not using it for extended periods of time, as it is slowly discharging , even if it is not hooked to the car, it is sulphating as the state of charge gets lower. The more times this happens, the battery looses it's ability to hold a charge. And finally one day it falls below the capacity needed to start a car. Now just to be clear on terminology, I take it from your statement that you understand that a tender is a float charger/maintainer, and not a tickle/trickle charger. There is a big difference and a trickle charger should not be used to maintain a battery for any long period of time unmonitored, especially Optimas. I just didn't want anyone to get the wrong message from this post, not being critical of you or your question. A trickle charger left unattended for a time period will definitely kill an optima and many others when the water boils out. A maintainer has the circuitry to not let this happen.
Luck to All

 

No offence taken, I will look into a float charger/maintainer when I return home next month. I knew there was a small load on the battery when sitting, so I call myself doing the battery a favor by disconnecting it. I appreciate the advise.

B

 

Hi, While reading through the sites that you provided links to I ran across some info to consider about the Battery Tender products. See Below..
++++++++++++++++++++++++++++++++++
Selection Guide


SEE THE PRODUCT SUMMARY TABLE AT THE BOTTOM OF THIS PAGE.


Deltran Charger Product Summary
Most Popular Models Highlighted
Charger Models Output Voltage Output Current Output Power Total Charging Software* / Battery Type AC Voltage / Frequency Input
(Volts) (Amps) (Watts)
Battery Tender Jr. 6V 0.750A 4.5W 3 Step STD & AGM 120 VAC 60 Hz
12V 0.750A 9W
Waterproof 800 12V 0.800A 10W 3 Step STD & AGM 100 to 240 VAC 50/60 Hz
(Automatic, Universal Input)
Battery Tender Plus 6V 1.25A 9W 4 Sep STD & AGM or GEL 120 VAC 60 Hz
++++++++++++++++++++++++++++++++++

As you can see the Batterytender Junior is rated at an output of .75 amps @ 12 volts. Now read below about the way a Batterytender Plus handles a AGM battery, and there is a big discrepancy between what the AGM battery needs and what the Junior can provide. And yet the literature from Deltran says a Junior will handle an AGM.
++++++++++++++++++++++++++++++++++
RECHARGING AGM BATTERIES: The Battery Tender Plus was specifically designed to accommodate the charging requirements of the new, Absorbed Glass Matte (AGM) style batteries. To achieve that goal, it was necessary to modify the absorption charge mode in the following way. The Battery Tender switches to float mode when the charge current drops to 0.5 amps. The Battery Tender Plus switches to float mode when the charge current drops to 0.1 amps. The result is that for an extended period of time, not to exceed 6 hours, the Battery Tender Plus output voltage will be held at a constant voltage that is significantly higher than the float voltage.

With the Battery Tender, the switchover at 0.5 amp results in an absorption charge mode length of approximately 1 hour. During this 1-hour period, the battery charge voltage is held constant at a value of approximately 14.3 volts. Because of the slightly higher voltage recharge requirements of AGM batteries, and because AGM batteries require a longer period of constant voltage absorption, the Battery Tender Plus controls the output voltage at 14.4 volts while it waits for either the charge current to decrease to 0.1 amp or for the absorption charge mode control timer to expire. The end result is that the Battery Tender Plus absorption period is longer and at a slightly higher voltage than that for the Battery Tender.
++++++++++++++++++++++++++++++++++
The comparison was between the Plus and a normal Tender, but you could extrapolate the performance of a Junior to be inadequate as well as a normal tender for AGM's
The junior only able to supply .75 amps would not be able to hold the charging rate needed for an AGM over a long enough period of time for it to come up to Full Charge. And therefore over time the Optima, or other AGM's would fail prematurely from lack of Full Charge maintenance. Possibly some of the folks out there experiencing this type of failure are using Juniors, or non plus tenders.
Luck To All..

 

Hi, no problem, that is a good idea, and you will have the added benefit of not having to unhook the battery when away.
Good Luck

 

Yes ... good catch. I see your point, and agree that the Battery Tender Jr doesn't seem to cut it for the Optima batteries based on Optima's required charging specifications. If that's the case, then I wonder why Battery Tender says the Jr. is compatible with AGM batteries ... I'm assuming all AGM batteries would require the same charging specs, but maybe not.

So, you guys who have had Optima batteries die at a frequent rate, are you using a Battery Tender Junior or some other kind of non-sophisticated "trickle charger" during the storage months?

 

I've been told previously by DELTRAN CORPORATION that their BATTERY TENDER JR. (@ .75 amp) will work on an OPTIMA battery just fine. It just will not keep the battery at peak charge as the BATTERY TENDER PLUS (@ 1.25 amp).
To some, the JR. is a "better" option due to physical size, availability at most motorcycle shops and slightly less cost.

 

I've been following this thread since it started, but some of the information in here is admittedly rather confusing to me. I have an Optima red top in my '01 Z06, and I recently ordered a Battery Tender Plus to use on the car. As of this moment I am still waiting for it to arrive.

Is the general consensus here that a Battery Tender Plus will or will not work on an Optima battery?

I'm rather baffled by the number of problems people seem to have with their batteries. My car is driven only once or twice per month, and it is usually for a short distance of no more than 18 miles. Other than that, the car just sleeps in the garage. I've had the Optima red top in it for about nine months now, and never once has the car been dead or slow to start.

I'm curious as to why I appear to be lucky in this case. I've been watching my battery voltage on the DIC when starting, driving, and parking the car. What is considered a "normal" reading?

LO PHAT

 

Yes, the Battery Tender PLUS looks to be compatible with the Optima batteries. I've used the Battery Tender PLUS on my Red Top for about 3 years now and it seems to work out well, as the Red Top holds a charge with time now just as it did when new - based on volage measurements with time as it sits in the car during storage.

Not so sure about the JUNIOR model since it only puts out 0.75A instead of 1.25A during charging mode. Even though Deltron has said it is (per Hotwheels57's post), it seems to not match Optima's charging spec data.