RET2
SILVER Star
A group 31 is a group 31 size wise. Terminal location/ type are the differences.
Question to Battery Gurus... (18 Viewers)
- Thread starter Markuson
- Start date
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About to bite the bullet and get the 31P-AGM7, hopefully I have better luck than what I've been reading! I'll be sure to purchase an Odyssey charger and use it monthly. Is there a particular Odyssey charger I should get?
RET2
SILVER Star
Deja vu... BTDT 
What is theSource? Do I want one?
I've had great luck with The BCDC and Northstars (AGM31A / AGM35). Not sure what all the fuss is.
4x4 sPOD
A solid state switching solution like sPod or SwitchPros is pretty fantastic. Highly recommended.
wrong msg plz delete
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Mike6158
Random Pixel Generator
I'm on the second 31P-AGM 7 in about 18 months. It doesn't seem to be holding a charge (dual battery system here too). The weird thing is that when I disconnect it completely from the LC and check the voltage I get 12.6 vs 12.8 on my backup battery. I can't help but wonder if something is fubar with the connect / disconnect relay
How are you checking the voltage? if you're testing after charging it you're probably detecting the surface charge. You need to put a load on it for a few minutes to remove that, at which point you'll get the real voltage.
As far as batteries dying, do you have the alternator diode hack or are you just charging normally along with the regular battery? AGM batteries have somewhat different charging requirements than flooded batteries. Also are you keeping that battery charged, or do you run it down and leave it? AGM can handle more cycles and go a bit deeper than flooded batteries, but it's harder to recover them if you overcharge or you drain them too far down, even once.
As far as batteries dying, do you have the alternator diode hack or are you just charging normally along with the regular battery? AGM batteries have somewhat different charging requirements than flooded batteries. Also are you keeping that battery charged, or do you run it down and leave it? AGM can handle more cycles and go a bit deeper than flooded batteries, but it's harder to recover them if you overcharge or you drain them too far down, even once.
Mike6158
Random Pixel Generator
I just made my own thread about this. This one was pretty long...
It's seeing the surface charge.
I don't have my electronic load here (I build and test Li FePO4 batteries so not completely out of my range of understanding). The load test is - after sitting a few minutes it won't crank the LC.
No diode hack. First I've heard of that one.
That's the one thing I can't claim to consistently do is keep a charge on it. I have a small solar panel that should keep it charged but, and this is a big issue that I hadn't clicked to until now, it does not have a charge controller on it. That's probably what knocked the battery out. Peak sun... who knows what the voltage is. It's designed to plug into a cigarette lighter but since Toyota turns those off
I have connected it to the battery with standard large battery clips. Since it's designed to back feed through a cigarette lighter socket I assumed the panel had a zener to limit voltage output but I don't know that...
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Ah ok. Some folks have lots of battery experience, some none. I put solar on my trailer some I have some working knowledge, but I'm not an expert.I just made my own thread about this. This one was pretty long...
It's seeing the surface charge.
I don't have my electronic load here (I build and test Li FePO4 batteries so not completely out of my range of understanding). The load test is - after sitting a few minutes it won't crank the LC.
No diode hack. First I've heard of that one.
That's the one thing I can't claim to consistently do is keep a charge on it. I have a small solar panel that should keep it charged but, and this is a big issue that I hadn't clicked to until now, it does not have a charge controller on it. That's probably what knocked the battery out. Peak sun... who knows what the voltage is. It's designed to plug into a cigarette lighter but since Toyota turns those off
If you're running a solar panel directly to the battery then I'd bet you're probably cooking it. At full sun most panels are ~19V, but batteries don't like more than ~14.6V or they start to boil. I'd probably hook up a multimeter to it to see what it's putting out at full sun before looking at much more complicated stuff.
The diode hack reduces the voltage the alternator sees on the battery which forces the alternator to run longer to reach the normal change (which would be overcharging your flooded battery but correctly charging the AGM). Or so the theory goes. I'm not sure how the alternator determines bulk vs absorption vs float charging, so I'm not entirely clear on whether the alternator charge cycle is "correct" for an AGM regardless of the peak voltage.
I didn't see your other thread. Is it in the 200 section? I've had a lot of battery experience and I've given up on AGM. I use flooded lead acid in vehicles and LiFePO4 in solar systems, with appropriate controller technology. As @linuxgod correctly noted, it's easy to damage AGM batteries beyond resurrection. If overcharged they cook themselves to death since they can't vent and if undercharged and left for a while (often even once) they sulfate up and can't be equalized to desulfate because they can't vent. AGM technology is useful in some specific applications and where they are keep properly charged, but I bought my last one a couple years ago and won't buy one again.I just made my own thread about this. This one was pretty long...
It's seeing the surface charge.
I don't have my electronic load here (I build and test Li FePO4 batteries so not completely out of my range of understanding). The load test is - after sitting a few minutes it won't crank the LC.
No diode hack. First I've heard of that one.
That's the one thing I can't claim to consistently do is keep a charge on it. I have a small solar panel that should keep it charged but, and this is a big issue that I hadn't clicked to until now, it does not have a charge controller on it. That's probably what knocked the battery out. Peak sun... who knows what the voltage is. It's designed to plug into a cigarette lighter but since Toyota turns those off
Mike6158
Random Pixel Generator
I'm definitely not an expert. I need to test the panel. I was made for cigarette lighter and had optional gator clips. I'll bet the zener is in the cigarette lighter plug I'll try to put the Fluke on it in the next day or two.
The charge controller that I normally used maintains the voltage for lead acid batteries. I also have some for LiFePO4's. <-- really nice batteries bit expensive
I'll try to put the Fluke on it in the next day or two.The charge controller that I normally used maintains the voltage for lead acid batteries. I also have some for LiFePO4's. <-- really nice batteries bit expensive
Mike6158
Random Pixel Generator
Well shoot... All this time I thought I was in the 100 series area. My post is in the 100 series section. When I saw this post I thought "now why would I post in the 200 section?"
I'll be scurrying back over there now...I'm going to switch to flooded lead acid. My first one died from undervoltage. I think this one did as well but there's also a good chance that I over volted it. We'll see...
LiFePO4's are nice batteries but I don't think they would be happy under the hood in the desert or anywhere else for that matter. Mine are all used in solar / remote Ham radio ops service.
Markuson
SILVER Star
- Thread starter
- #116
This is an old, long thread indeed.
That said, I can tell you that I have stopped using the Interstate battery originally referenced after two premature failures.
However...the Type 35 Odyssey batteries I used faaaar outlived their normal life spans, despite my (very likely) unprecedented level of strain I put on them.
If you haven’t heard of the resistor/diode charge hack, and you use an AGM main battery, you need to look into it....unless you’ve already moved to a DC to DC charger unit by are darcy or some others. Without either, your AGMs will never fare well long term without regular battery tending.
I use an HKB tweak that tricks the alternator into charging at its higher level voltage than it tends to without, and it’s helped a lot.
Ressurrecting an old thread.
About 3 years ago, I installed the X2 AGM and have been happy with the results. Completed the resistor/diode hack to complement the AGM.
Recently, I can sense a slight hesitation during start up. Am thinking that the battery is getting weaker and will replace proactively in the near future.
Am thinking to go back to regular flood battery. Costco Interstate batteris are inexpensive initial cost and their warranty is just hard to beat. If it dies within three years, they replace the battery for free.
My question is, going back to regular flood battery with the resistor/diode hack in place, I believe that means the regular battery will now get overcharged. Is that necessarily a bad thing? Or should I remove the resistor/diode hack before installing the regular battery?
About 3 years ago, I installed the X2 AGM and have been happy with the results. Completed the resistor/diode hack to complement the AGM.
Recently, I can sense a slight hesitation during start up. Am thinking that the battery is getting weaker and will replace proactively in the near future.
Am thinking to go back to regular flood battery. Costco Interstate batteris are inexpensive initial cost and their warranty is just hard to beat. If it dies within three years, they replace the battery for free.
My question is, going back to regular flood battery with the resistor/diode hack in place, I believe that means the regular battery will now get overcharged. Is that necessarily a bad thing? Or should I remove the resistor/diode hack before installing the regular battery?
Well, I may have stumbled across an answer.
In short, It seems the additional ~0.5v won't really be harmful. If I recall, I saw 13.7 or 13.8v with the resistor/diode in place. In fact, it could be good for the lead acid battery to be charging at 13.8V.
Battery can apparently operate 14.4V to 15V during bulk charge phase, which sounds like that is ok as long as the battery isn't fully charged. After it is charged, it sounds like dropping back to the float charge (13.8V) is recommended.
I read a complaint that the diode/resistor hack not going above 14V was a disappointment for optimally charging AGM batteries.
Having run the AGM for three years in AZ (where batteries regularly die after two years), that complaint didn't seem to be too negatively impactful. And now that I'm going back to lead acid, am thinking it is good that the diode/resistor brings the voltage to just 13.8ish.
Please check my thought process. I do not pretend really know this subject matter.
Below are the sources consulted...
In short, It seems the additional ~0.5v won't really be harmful. If I recall, I saw 13.7 or 13.8v with the resistor/diode in place. In fact, it could be good for the lead acid battery to be charging at 13.8V.
Battery can apparently operate 14.4V to 15V during bulk charge phase, which sounds like that is ok as long as the battery isn't fully charged. After it is charged, it sounds like dropping back to the float charge (13.8V) is recommended.
I read a complaint that the diode/resistor hack not going above 14V was a disappointment for optimally charging AGM batteries.
Having run the AGM for three years in AZ (where batteries regularly die after two years), that complaint didn't seem to be too negatively impactful. And now that I'm going back to lead acid, am thinking it is good that the diode/resistor brings the voltage to just 13.8ish.
Please check my thought process. I do not pretend really know this subject matter.
Below are the sources consulted...
Frequently asked questions about car batteries, how much does a car battery weigh, what is the car battery voltage, can car batteries freeze, can one battery charge another, car battery discharge?
Car cigarette lighter voltage and amps,12 volt car battery charging voltage, charger voltage,automobile battery voltage
www.powerstream.com
How to charge all lead acid batteries; how to charge SLA lead acid batteries, a tutorial for engineers about lead acid chargers and charging.
12V SLA battery charger,lead acid battery charging techniques and algorithms,sealed lead acid batteries,Pb battery,SLA,VRLA,Gel,Flooded and AGM batteries.
www.powerstream.com
If the battery is actually on its way out and can be tested to demonstrate such, don't X2Power batteries have a 48 month free replacement policy? If nothing else, a replacement battery that you can easily sell for $300 affords you a FLA battery, a fifth of nice bourbon, take out of your choice... and still a weekend's worth of beer.
Just called Batteries Plus Bulbs.
X2 automotive applications are covered by 5 year warranty.
Associate said come in and test it; if on it's way out, full replacement.
Think I'll be taking a drive this afternoon...
