Odyssey (or general Battery) Maintenance Charging

Airmapper

High-Tech Redneck
Long post alert, nerd and geek territory ahead.

I've been having some difficulty understanding the best practice regarding Odyssey batteries, and what you might call routine maintenance charging. I assume this would carry over to general automotive batteries as well, but I'm mostly curious about Odyssey. (I presume Optima batteries would fall under nearly identical care guidelines.)

I've seen charging discussion on here, but most of those deals with either deep cycle or extended drain, running relatively power hungry equipment overnight while camping and such. However I don't see much discussion on day-to-day charging. I've read in various places that Alternators, and the irregular cycles of driving, really don't give the battery a proper top off like a charger would, therefore making it desirable to charge your vehicles battery on a regular basis, even if it is not in a state of discharge, to top it off completely, perhaps other benefits as well.

In my situation I have a Group 31 Odyssey installed in my Xterra. I do not deep cycle it, I got it for expanded potential power, and the benefit of being able to get more from it in an extreme situation, (winching, 12v air compressor, charging electronics, etc...) but that is secondary to it's primary function of the boring life of a typical automotive battery. On a typical week the most draining task I may place on the battery while the vehicle is not running is playing the radio for several hours. It is driven regularly, my normal commute is almost an hour, I do that twice a day. In the future I may ask more of it while camping, but that is another topic more frequently discussed here.

I've seen documentation on needing a "special" charger for the Odyssey. On researching it, it appears this is primarily to supply a 14.7V charging voltage and ensure high amperage charging (as much as 50A) as the Odyssey seems to recharge better at those specifications, particularly in situations where it has been deeply discharged, and while you may not "need" this special charger, it is recommended if your using it in an application where it is deep cycled frequently. I could see myself purchasing a charger of that grade if I repeatedly deep cycled my Odyssey, which as of yet I do not.

I have a few chargers at my disposal. My newest and favored is a NOCO Genius 3500. (3.5A max) I do have an older (but still "smart") charger capable of higher amperage (4A,10A, & 20A I think.)

So my question is, as a standard practice, is it best to charge an Odyssey, needed or not, on a regular basis. Say every other weekend, once a month, or such. Or is it purely a matter of voltage, so long as it's in the full range (12.84V or more is considered 100%) am I fine just ignoring it, confident the alternator is keeping it charged and healthy so long as I don't do anything extreme to it.

Just a minute ago, I checked my voltage. It is 12.79, that is very close to 100% but not quite. I figure that is it's typical voltage, I have not placed it on a charger since installation a few months back. It has been maintained solely by the vehicle's charging system since.

And while we are on the topic, if it is necessary to charge on a regular basis, would a small solar setup eliminate the need for scheduled charging, and make it nearly maintenance free so long as you never deeply discharge?
 

228B

Observer
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I have a Group 31 Odyssey/DieHardPlatinum 100Ah AGM battery. According to the profile output by an EnerSys OMAX - 50A - 1B (a recommended charger for the Odyssey AGM), and at a battery resting State Of Charge of 70%, 50 amps will go to the battery @ 13.6 during the bulk charge sequence, with amps tapering off as voltage rises to 14.7 for absorption, which takes an additional 3 to 4 hours. Finally, the charger will float this battery at 13.6 volts. EnerSys says that the charger may remain connected to the battery indefinitely.
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An Odyssey battery tech I spoke with last year, the fella who recommended that charger, told me that these batteries like to be hit hard during the bulk phase of the charge profile, that they require 14.7 during absorbtion, and should be floated (indefinitely without harm) at 13.6 volts.
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I'm making the necessary changes now to a solar charge controller to accommodate these parameters, although the maximum bulk amperage from solar may never really be higher than 12 to 13 amps @ +/- 14V.
 

comptiger5000

Adventurer
A vehicle alternator will do a great job of meeting the high bulk amperage desires of that battery. If you don't drain it particularly far, an hour of driving a day is probably enough to keep it pretty well topped off without outside charging, assuming the alternator is putting out a high enough voltage.
 

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Wicked 2007

Observer
I use the EnerSys OMAX - 50A - 1B for my engine bay battery to charge/tend while parked. For my house battery in my NLPP I use my solar setup to keep it topped off. I am able to program my charge controller to charge per Odyssey specs for each phase of charging/tending.
 

Airmapper

High-Tech Redneck
A vehicle alternator will do a great job of meeting the high bulk amperage desires of that battery. If you don't drain it particularly far, an hour of driving a day is probably enough to keep it pretty well topped off without outside charging, assuming the alternator is putting out a high enough voltage.
Yes, that is what I'm getting at. The vehicles charging system in my vague understanding of it, will treat the battery like bulk charging mode all the time, or rather it maintains a predetermined voltage by alternating off and on giving amperage as needed. It's designed to take care of the vehicles needs, not the battery. The battery never gets a dedicated absorption phase, or any controlled float. It spends all it's time when I am driving at what the vehicle decides it needs, and when I'm not driving it is at a 95-99% full state.

I'm wondering if for reasons such as maintaining chemistry, or general longevity, if regular top off charging will have any pronounced benefit over just leaving it to the vehicles charging system alone. It will never get very low, but it will never be totally full either, without some outside assistance.

The battery is only rarely going to see any significant discharge, which is an ideal life for a battery overall, but hardly necessitates expensive bulky chargers. I'm talking about something much more simple and easy to perform as opposed to either hooking it up to a high performance charger every time it's parked, or even on weekends. For example my NOCO came with quick connects, I can wire one to the battery permanently and plug it in during the weekend overnight one time, and that will be that. Depending on how I set it up, I may not even need to pop the hood. Quick and easy means it's more likely to get done.

If there is no significant benefit to be had from charging a mostly full battery, then that means they truly are maintenance free and then there is no need for anything. But if it means I'll actually get 10 years of life out of a battery touted as being capable of that kind of service, I'll rig something up to treat it well so I get that kind of performance from it. Be that weekend charging, or a small solar panel to top it off while it sits parked with the sun beating down on it.
 

228B

Observer
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I'm wondering if for reasons such as maintaining chemistry, or general longevity, if regular top off charging will have any pronounced benefit over just leaving it to the vehicles charging system alone...
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These batteries like to be floated at 13.6.
 

comptiger5000

Adventurer
Once the battery is charged and not pulling much amperage, having the vehicle running is like having a continuous absorption phase running on a charger. It's kept somewhat above float voltage and will definitely hit 100% charge after a while. The issue comes when you drain a battery down a good bit, it might take weeks of normal driving with not much drain in between to get it truly topped off. But with frequent, longer drives and not much draw in between, it should stay topped off perfectly fine from just the alternator.

FWIW, no battery in a vehicle will truly stay at 100% charge no matter what you do, as there's always small draws from the vehicle and such.
 

DiploStrat

Expedition Leader
Yes, that is what I'm getting at. The vehicles charging system in my vague understanding of it, will treat the battery like bulk charging mode all the time, or rather it maintains a predetermined voltage by alternating off and on giving amperage as needed. It's designed to take care of the vehicles needs, not the battery. The battery never gets a dedicated absorption phase, or any controlled float. It spends all it's time when I am driving at what the vehicle decides it needs, and when I'm not driving it is at a 95-99% full state.
Depends on the vehicle. Your statement is certainly NOT correct for a recent Chevrolet and I can't believe that Ford or RAM are much different. In any case, you will never run your truck long enough to need a float stage.

I would recommend some quality time with the shop manual for your vehicle before you invest any form of on board speciality charger; you probably don't need it.

Solar, on the other hand, to complete the absorb stage, is invaluable.
 

Airmapper

High-Tech Redneck
Thanks guys. My understanding of electronics is just enough to be dangerous but not enough to be good at it. I'm sure I'll get formal education on it at some point as I'm in college in a technical field.

At most what I had planned was to periodically charge the battery if the vehicle was not really taking care of a battery like an Odyssey adequately. I get the impression it does an adequate job and unless I discharge it significantly I can leave it be.

Honestly, just because I like to tinker, I thought of adding some form of solar charger just for the experience. At some point I'm sure I'll be wanting to do a larger project (like a trailer) and want to do it there. Part of why I got an Odyssey is I think I could get by without an on board second battery for any reason. I can use a jump pack if I don't have enough juice to start the engine. If I ever go to a trailer setup, I could of course have a battery setup there for any significant power needs.
 

DiploStrat

Expedition Leader
I you go to my website and look under "Documents" you will find lots of pedantic information on this very subject, all with links to reasonably authoritative sources. Hope you find some of it useful.
 
Sorry to revive this thread but wanted to see what the experience of others in the community has been with Odyssey AGM's. I have a Group 34, that is about 2 years old and has been in my 4runner for about a year. Until about a month or so, I was periodically (once every month, sometimes more frequently) AC charging the battery (disconnected from the vehicle) overnight. A few weeks ago, I installed a voltage booster that delivers roughly 14.4 volts to the battery at startup idle. I haven't since discharged the battery significantly (maybe used the air-compressor a couple of times) or made any attempts to AC charge it. The voltage I get at the terminals after about 10-hours of engine off (but with the normal stock vehicle load (like alarm system etc) connected overnight) is around 12.77 v. Odyssey claims 100% SOC at or above 12.84 Volts so I wanted to know what I see is nominal given some discharge overnight with the load? I measure voltage at the terminals but recently ran some 4 AWG wires back to the trunk and get the very same reading there as well. I realize that I could remove the battery, AC charge it and leave it sit idle off the charger and measure resting voltage but wanted to see what others have been getting from their vehicle with the battery installed.

One of my reasons to look at it installed is to ascertain how good my vehicle (with the voltage booster) is at keeping an AGM happy. This before solar or any other form of additional support (like AC). I want to understand this before I make a decision to put in a much larger AGM in there which would be a waste if my system can't efficiently top it up and keep it healthy.
 

Attachments

RandyP

Adventurer
Sorry to revive this thread but wanted to see what the experience of others in the community has been with Odyssey AGM's. I have a Group 34, that is about 2 years old and has been in my 4runner for about a year. Until about a month or so, I was periodically (once every month, sometimes more frequently) AC charging the battery (disconnected from the vehicle) overnight. A few weeks ago, I installed a voltage booster that delivers roughly 14.4 volts to the battery at startup idle. I haven't since discharged the battery significantly (maybe used the air-compressor a couple of times) or made any attempts to AC charge it. The voltage I get at the terminals after about 10-hours of engine off (but with the normal stock vehicle load (like alarm system etc) connected overnight) is around 12.77 v. Odyssey claims 100% SOC at or above 12.84 Volts so I wanted to know what I see is nominal given some discharge overnight with the load? I measure voltage at the terminals but recently ran some 4 AWG wires back to the trunk and get the very same reading there as well. I realize that I could remove the battery, AC charge it and leave it sit idle off the charger and measure resting voltage but wanted to see what others have been getting from their vehicle with the battery installed.

One of my reasons to look at it installed is to ascertain how good my vehicle (with the voltage booster) is at keeping an AGM happy. This before solar or any other form of additional support (like AC). I want to understand this before I make a decision to put in a much larger AGM in there which would be a waste if my system can't efficiently top it up and keep it healthy.
I cannot find the tech manual they used to share on their web site. But big group 31 Odyssey batteries require a higher voltage charge than others about once a week to keep them happy. I did find this info from Odyssey about battery recovery, with similar info:


If the charger will not engage, the following procedure can be used – 1. Using jumper cables connect the positive terminal of a healthy battery to the positive terminal of the dead ODYSSEY battery; then connect the negative terminal of the healthy battery to the negative terminal of the ODYSSEY battery. If you are using the battery in a car, do not run the engine during this operation. 2. Monitor the voltage of the ODYSSEY battery with a good quality voltmeter until it reads 11.5-11.8V. 3. Disconnect the jumper cables on the ODYSSEY battery, then quickly connect the positive cable of the charger to the positive terminal of the ODYSSEY battery; then connect the negative cable to the negative terminal of the ODYSSEY battery. 4. The charger needs to be of a minimum charge current capability per the chart below. 5. Plug the charger into standard wall AC power and start monitoring the battery voltage. 6. Make sure the charge voltage at the battery terminals does not exceed 15.0V and continue charging for approximately 8 hours. 7. Disconnect the charger and allow the battery to sit open circuit with no connections for 12 hours or install the battery and turn the headlights on for 2 minutes to remove the charging surface charge voltage. Turn the headlights off, allow the battery to rest for a few minutes and read its voltage. A fully charged ODYSSEY battery will read 12.84V verifying a full charge. Battery Models Minimum Charging Amperage PC310 – PC680 6 amps* PC925 - PC1200 12 amps* PC1220 – PC1750 25 amps* PC1800-PC2250 50 amps*

it takess a 50Amp charger to perform this process on a truck battery.

Here's the technical manual I had referred to, found it.
P 15-17 for charging and p 19 is interesting for no idle applications.



I appreciate Odyssey honesty and thorough tech info !
 
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jonyjoe101

Adventurer
I have the fullriver fullthrottle 27ah agm, its a clone of the oddysey and looks the same and has about the same voltage/amps requirement. Its a 8 year old battery, recently I been using it as my start battery. I don't drive alot and notice after sitting several days it will give me a slow crank while starting.

What I been doing is just keeping a 2 amp 14.7 volt charger connected 24/7 from the house battery to the start battery. I been doing that for the past 3 months and I get excellent cranking power when I start it every time. The oddysey also requires 14.7 to fully charge. The alternator 14.4 volts just won't fully charge these high performance batteries. The alternator can give it the high amps it needs to get to 80 percent during daily use but once in while connect a lower amps charger that can top it off to 14.7 volts. For best longevity the agm needs to be fully charge everyday.

I like the extreme performance I get with it being connected at 14.7 volts all day long, the charger is smart enough that most times its not even passing current, just maintaining 14.7 volts. When I had the fullriver connected to my house battery lifepo4 at 13.1 volts 24/7, that didn't really help, sometimes I would even get slow cranks.

I wouldn't rely on the battery voltage for SOC, if you only been charging it to 14.4 volts, the battery has never received a full charge. Chronic undercharging will result in lost capacity which will affect the SOC.

fullriver.jpg
 

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The alternator 14.4 volts just won't fully charge these high performance batteries. The alternator can give it the high amps it needs to get to 80 percent during daily use but once in while connect a lower amps charger that can top it off to 14.7 volts. For best longevity the agm needs to be fully charge everyday.
I should have been a bit more clearer in my post. Odyssey recommends that "in deep cycling applications it is important to have the charge voltage set at 14.4 – 15.0V." My alternator and VB can deliver that as I can increase my voltage from 14.2-14.4 range (which is what I have it currently set at) to 14.6-14.8 if required (again idle and after starting). I intend on doing this in the winter and when I begin cycling it with heavier loads. I'm just trying to see if, despite voltage boosted to AGM desired levels, smart alternators are still capable of keeping these things relatively happy in the long term. My AC charger was used extensively over the last year but I recently moved to an apartment that doesn't have a power source where I park so I wanted to see if physically taking the battery up 4 flight of stairs was absolutely necessary for long term health. This will be an even more PITA if and when I decide to upgrade to a G27 battery size.
 
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RandyP

Adventurer
I have the fullriver fullthrottle 27ah agm, its a clone of the oddysey and looks the same and has about the same voltage/amps requirement. Its a 8 year old battery, recently I been using it as my start battery. I don't drive alot and notice after sitting several days it will give me a slow crank while starting.

What I been doing is just keeping a 2 amp 14.7 volt charger connected 24/7 from the house battery to the start battery. I been doing that for the past 3 months and I get excellent cranking power when I start it every time. The oddysey also requires 14.7 to fully charge. The alternator 14.4 volts just won't fully charge these high performance batteries. The alternator can give it the high amps it needs to get to 80 percent during daily use but once in while connect a lower amps charger that can top it off to 14.7 volts. For best longevity the agm needs to be fully charge everyday.

I like the extreme performance I get with it being connected at 14.7 volts all day long, the charger is smart enough that most times its not even passing current, just maintaining 14.7 volts. When I had the fullriver connected to my house battery lifepo4 at 13.1 volts 24/7, that didn't really help, sometimes I would even get slow cranks.

I wouldn't rely on the battery voltage for SOC, if you only been charging it to 14.4 volts, the battery has never received a full charge. Chronic undercharging will result in lost capacity which will affect the SOC.

View attachment 604628
All you state is true. Sears used to sell a platinum line of Odyssey manufactured or relabeled batteries. Same specs as the Odyssey battery, 8 year replacement and 10 year prorated life as i remember. Used a pair for 8 years in a Ford F250 diesel pickup. About that time sears started closing it's stores and disappeared. I got 8 years of the pair, one failed at the 8 year point and was replaced by sears at no cost except retail inflation & tax to me. The Odyssey warranty was for fewer years than the Sears warranty!
If the battery cannot be fully charged by the methods I linked above, it's probably getting tired. After 8 years, its a possibility. Keeping it on the trickle charger is a good way of continuing to use it. Odyssey is still turning out good batteries, you can get a replacement from them when you are ready for one.
I'm still running a pair of Odyssey batteries in the F250.
 
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