Battery Issues

TemboTusk

Rendezvous Con
I have a Sears Diehard Platinum group 34 as my 2nd battery which I use to run an Engel 35 liter fridge. I use the National Luna split charger to maintain both the starting and accessory batteries.

Suddenly I found my battery pushing 8.5 volts after about 8 hours of running the fridge. I put a charger on the battery and brought it back to 13.5 volts and it dropped back to 12.2 not long after removing the charger.

After running the fridge for another 6 hours, the battery reading is now 11.8 volts and dropping.

The battery is about 5 month old and I had Sears check it. They indicate the battery is fine.

Back ground info: For the last few days, I have been making only short trips around town with the vehicle. In other words; 5 minutes here, 10 minutes there, maybe 15 minutes somewhere else. It could be not enough time to maintain the auxiliary at full charge?

Do you think I have a dying battery or some other issue. I'm concerned about the rapid drop in voltage after a full charge.

Thanks for any help.
 

4RunAmok

Explorer
Hey Jerry!

You didn't mention the type of battery charger you used. For AGM's, we use CTEK chargers at work. They understand how an AGM needs charging, and uses the right modes to do it (Bulk, Absorption, Float, etc), and many of their models include Recondition modes, to help restore a battery's health.

This is one of their better models, $149.00
http://smartercharger.com/products/batterychargers/ctek-multi-us-7002/

Something you might consider if your truck sits for awhile, hard mount the charger inside the vehicle, wire it into the battery posts, and either install a shore power port on the side of the truck, or just let the cord dangle out the back while you have it hooked up to an extension cord. It's perfectly fine to let this device keep a battery on a trickle all the time. It will help keep sulfation down.
 

TemboTusk

Rendezvous Con
Mitch,

I use a charger I inherited from my Dad; A 10 amp charger bought in the late 1960s. . . It might be time I buy a new one!! Thanks for the link.

I use the vehicle as a daily driver; that's why I was so surprised at the rapid drop in the voltage. It might be a perfect storm of using the aux battery and short trips around town. But, since I'm heading to Moab in a few days, I want to make sure the battery is OK.
 

4RunAmok

Explorer
A new charger is definitely in order. AGM batteries require much smarter chargers than just throwing heat at them! :)

Sounds like a solar setup might be in your future as well! haha!

The battery is quite young to be having these issues, but then, Odyssey batteries have been known to have faults. Will Sears replace it, no questions asked? If yes, I would do it.

It could be that your charger just didn't give the battery what it needed to stay charged.
 

TemboTusk

Rendezvous Con
I will return to Sears in the AM. Their limited test indicated it was fine, but I would feel much better with an exchange. Funny, I bought the battery thinking I was buying the best. Odyssey/Platinum was expensive.

I hear you about "throwing heat". That old charger is like a blow torch.
 

4RunAmok

Explorer
You did buy one of the better batteries out there. One can slip through QA now and then. And the battery could be just fine, but your charger isn't up to par. But if you're leaving on a trip, take advantage of the warranty for peace of mind.
 

TemboTusk

Rendezvous Con
I hear you on the warranty, however, I'm afraid they may deny me on account they view the battery as good according to their test. I might have to throw a fit!!
In the mean time, I will be picking up the recommended charger and give the battery a proper charge.
 

unseenone

Explorer
Hi Jerry;

I would suggest taking the battery in for an overnight test. Try and independent auto part shop or batteries plus for example. They may not charge you, ask for the printout and bring it with you if it turns out it is bad. That's the route I went with a bad 2 year old Optima Yellow top purchased from NAPA. Brought in the battery and test results, and they ordered a replacement, which came in the next morning. You can't tell much without a more extensive test.

On another occasion my interstate primary battery went bad (again) and I run it through a few days or charging overnight on the ctek, etc. I was 100% confident it was bad. Took it down to their distribution store, and they said, no, it's fine. I pushed the issue and said, I insist it is bad. and they relented and provided a replacement under warranty.

I also have the ctek-7002 mentioned, it does a decent job, just remember it's slow slow slow. I'm looking into solar as well, it makes the most sense for keep the batteries topped up, and hopefully last longer by not discharging them as much.

Nice products by the way, one of these days..
 

TemboTusk

Rendezvous Con
Early update: After putting the battery on a charger for six hours, I ran the fridge all afternoon and night set at 32 degrees. Checked voltage this morning and it says 11.5 volts. I think that is acceptable. The fridge has been running since 1pm Tuesday till 6am Wednesday with no engine.

I think my initial low battery may have been caused by too much auxiliary battery use in the couple of days leading up to the low battery reading ands too little driving. The National Luna Split Charger unit only starts charging the second battery after five minutes of the start of the engine. Because I have been doing only short runs to the store this week, such as a five minute drive to the Home Depot and a five minute drive back home, or eight minute drive to the office etc. The battery may have never received an adequate charge. I don't typically run with the fridge on while at home, but this week I needed the fridge for various reasons.

My conclusion is that the battery is fine and that I just ran it down with the short drives around town. Lesson learned.

Thanks guys for the help. It got me thinking in the right direction and I will be picking up new charger!!


Unseenone, thanks for the compliment! It only hurts once, but lasts a life time!
 

unseenone

Explorer
Agreed. I've got a National Luna I would like to mount up, but the slide needs to extend / drop beyond the tailgate because I don't have storage box. It's an LR3, can we get there.
I thi
I would suggest putting a 100w solar panel and a Small Morningstar controller. That's the route I've decided to go, I think perpetual continuous discharge is worse for the battery than anything else.
 

TemboTusk

Rendezvous Con
I will start investigating for a solar system.

The biggest problem with an the LR3 is the limited cargo space behind the back seats. The drop down needs at least 35" of space behind the back seat. Once deployed it should clear the rear bumper. If you don't have storage boxes, a flat slide may very well do what you need. The TemboTusk flat slide only needs 28" inches and extends 100 percent. When you are ready, send me a PM or email and we can discuss what will work best.
 

Martyn

Supporting Sponsor, Overland Certified OC0018
Jerry, the dual battery system will stop recognizing the aux. battery if the voltage drops below 10.0 volts, or so. Basically it thinks that there is no battery in the system and won't send a charge to it. We fit low voltage disconnects into the auxiliary battery side so that the accessories are disconnected before this point is reached.

On the charger side I'd agree with what has been said about smart chargers, they are the way to go in most cases. We have had a few 'dead' AGM batteries that the smart charger will not bring back to life. Alternating between a smart charger and a standard charger has returned them to full health.

Sears batteries. Good batteries, branded by Sears and made by good manufacturers. What seems to be missing is the QC. Not a huge factor as Sears will replace the battery if it goes bad. An issue if you are remote the battery stops working and your beers is warm.
 

TemboTusk

Rendezvous Con
Thanks Martyn,

I don't currently have a low voltage disconnect. My fridge is too old to have that built in. I'll look into it and talk to you about it at Expo.
 

wrcsixeight

Adventurer
Odyssey makes a good battery.

They also have a great data sheet informing their customers how to properly recharge their batteries, and an alternator with short trips around town comes no where near the same galaxy as their prescribed regimen.

Check page 12 on the following PDF
http://www.batteryplex.com/sheets/Odyssey%20Application%20Manual.pdf

When Deeply cycled, an Odyssey battery wants a 40% charge rate.

A group 34 is 68 amp hours?, then it wants a charger capable of at least 27 amps.

It wants 27 amps until 14.7volts are reached. Once reached, 14.7v is to be held for 4 hours as the current tapers, then float at 13.6v.

Not meeting these specs when deeply cycling an Odyssey battery will yield poor performance and a short life and an indignant customer.

If the battery is just used as a starting battery and not deeply cycled then this 14.7 for 4 hours regimen is not required.

An odyssey engineer I spoke at length with told me an improperly recharged battery would require 3 cycles down to 50% and proper recharge before the battery will be back at its full remaining capacity.

It is not easy to find a regular charger which will meet the 40% rate and hold 14.7 for several hours.

The List of odyssey approved chargers is small. DO not bother buying one which can't at least meet the 40% rate. Odyssey does have their own line of chargers made by Schumacher but they are $$$.

There is more than charging a lead acid battery than just slapping a charger on it or a quick run around town with a high dollar Split charge relay. Odyssey is one of the best AGM batteries out there, but they are finicky how they are recharged.

Traditional low and slow mentality and 'trickle' chargers or even new high tech maintainers, are NOT sufficient.

Old school manual chargers can eventually get the battery voltage high enough to pop the vents. Thermal runaway can be an issue with AGM on manual chargers too.

Proper recharging is paramount.

Slapping just any charger on it is unwise.
Not having thick cables to transfer maximum alternator current to the battery, is unwise.

Sure any battery manufacturer can send out a bad unit, but jumping to that conclusion when the battery is obviously improperly recharged is... unwise.
 

unseenone

Explorer
Thanks Martyn,

I don't currently have a low voltage disconnect. My fridge is too old to have that built in. I'll look into it and talk to you about it at Expo.

Thanks for the offer, I'll drop you a PM with my info.

I used Anderson connectors on the feed line to the rear, with a 40amp rated disconnect. There is another company that makes a 20amp one that you can set the cutoff behavior on jumpers. Mine are installed in the battery box. The only annoying thing is over over voltage cut off, which might be tripped when it's deeply discharged after you start the vehicle. You may be able to disabled it, I haven't looked into it. The nice thing, is you can also protect your radio equipment, as well as your fridge and battery. Wired with Anderson plugs, you can remove it in an emergency.

I put on two of the PWRguard plus on this page (one for each power run) http://www.powerwerx.com/fuses-circuit-protection/

I snapped a picture for you of them installed, if you want to see it. http://www.disco3.co.uk/gallery/thumbnails.php?album=35750
 

Forum statistics

Threads
185,541
Messages
2,875,682
Members
224,922
Latest member
Randy Towles
Top