RET2
SILVER Star
There is a diode fuse that will bump the charging up approximately .6 volts giving the necessary 14.4 charging volts. There are several threads about this.
Question to Battery Gurus... (1 Viewer)
- Thread starter Markuson
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mcgaskins
SILVER Star
I have the Slee upgrade tray and the Interstate 31P-AGM7 which is actually the second truck I've done the exact same treatment to. The most recent one I installed in May, and it died a couple of weeks ago. My battery tester showed 3% health even on a 100% charge. I use the Odyssey OBC-20A conditioner/charger on the AGM batteries at least once a month to keep them topped up since the alternator has been shown to not quite get it to 100%. I returned the 31P-AGM7 to get a warranty replacement, and they suggested I try the 31M as well. We wheeled it out to the truck, put it in the tray, and the terminals don't quite work with the Slee setup. I replaced with another 31P, and all has been well since. I think the key to a good long life with these AGM batteries is to put it on a good conditioner/charger periodically and monitor from time with a battery tester (like this one https://smile.amazon.com/gp/product/B01M0ARG3X/ref=oh_aui_search_detailpage?ie=UTF8&psc=1) to make sure everything is ok.
RET2
SILVER Star
I suspect something is very wrong unless you had a bad one from the start? 3 or 4 month life is crazy. Be sure to check conections on the Slee terminals as there have been reports of corrosion issues.
mcgaskins
SILVER Star
Just like Mark's original post in this thread, I got a defective unit. There's no corrosion at all - just a bad battery.
Just a head's up to those who want to know more about the diode fuse to bump alternator voltage that RET2 referenced, the below thread was helpful:
Odyssey Batteries - How to Charge? Diode or DC DC Charger?
Highlights
Odyssey Batteries - How to Charge? Diode or DC DC Charger?
Highlights
- parts cost ~$40 + shipping
- supposedly just plug and play - extract the old 7.5A Alternator Sense Circuit Fuse and insert the alternator voltage booster (includes 7.5A fuse it replaces)
- voltage alternator will increase output ~0.5V
- supposedly no negative impact to the rest of the electrical system
- does not seem to work for the '16+ LC200s
- enjoy a well fed, happy AGM battery
I wish the diode value was available, diodes are $0.10 each
I think this is mostly true as long as “happy AGM battery” is looked at as relative to without the diode. I will say that even with the diode, my AGM batteries are never 100% charged. You need a multi stage charger that has the ability to cater itself to an AGM battery. I have, but have yet to install a Redarc DC-DC charger too. This should at least keep my aux/house battery topped off.
Diodes are pretty simple, 1A, 3A and 6A being the most popular for aftermarket automotive use. I used a simple series diode and fuse. It isn’t beautiful, but it was free
And the fuse box lid hides it...
Thx for the clarification 619TOY. Good point.
For an amateur electician such as I am running a single agm in the primary tray (no aux), how often should I plan to supplement my agm battery w external charge to keep her pretty and plump?
For an amateur electician such as I am running a single agm in the primary tray (no aux), how often should I plan to supplement my agm battery w external charge to keep her pretty and plump?
^^^
For the above, assume the voltage booster is in place.
And the amateur electrician overpaid for the Aussie HKB just to play it safe...
For the above, assume the voltage booster is in place.
And the amateur electrician overpaid for the Aussie HKB just to play it safe...
Taco2Cruiser
Crazy American Off Road
A Northstar 31 marine fits (just barely) within the factory plastic battery tray. Which in my opinion is better because... what is really gained from adding a heavy metal tray that requires drilling, when there is already a super strong metal tray?
I made my own tie down, but from what I remember the interstate is 9.375” tall versus the Northstar which is 9.78”. So not putting in the Slee tray, will buy you some additional space for the Northstars tall profile. Double check my numbers though. But I think you can play with the Slee tie down to make it work.
Given the Interstate is not available locally (apparently sold out across the entire East Valley of Phoenix) and the X2Power 31M is on the shelf at multiple local Batteriesplus stores, I may just be going the Northstar route.
As the voltage booster is now on order from Oz, will see if the 31P is back in stock when the HKB arrives next week and then make a decision. The ease of getting a replacement weighs on the mind, though. Maybe I'll just get impatient, go X2 when am home on Friday, get her back on the road, and throw on the HKB whenever it arrives.
Decisions, decisions...
If I do go X2, will let you know what (if anything) I use from Slee's primary tray kit. That gets delivered tomorrow.
As the voltage booster is now on order from Oz, will see if the 31P is back in stock when the HKB arrives next week and then make a decision. The ease of getting a replacement weighs on the mind, though. Maybe I'll just get impatient, go X2 when am home on Friday, get her back on the road, and throw on the HKB whenever it arrives.
Decisions, decisions...
If I do go X2, will let you know what (if anything) I use from Slee's primary tray kit. That gets delivered tomorrow.
indycole
GOLD Star
I have the X2 Power 31M and top it off every month or so and definitely before any backcountry trip with an Optima charger. Even with the BCDC1225D (which keeps my aux Odyssey as happy as can be) the X2 is never close to being charged even after a long drive. I have the HKB fuse and as mentioned above it doesn't work on 16+.
Oddly enough, I've recently been exploring ways to keep the X2 charged but haven't come up with anything reasonable.
Oddly enough, I've recently been exploring ways to keep the X2 charged but haven't come up with anything reasonable.
Markuson
SILVER Star
- Thread starter
- #54
The diode voltage booster does help, though it still falls short of optimal, mainly due to the weird way voltage is controlled. It will definitely bump you up. I just wish it would STAY up. The slternator’s charge level starts out high...and then quickly lowers after 10 minutes or so of driving. The diode DOES keep it higher than without it...and that’s helpful...but to truly make the AGM 100% (or “happy”...) it still needs more.
I may try adding IBS’ new add-on DC-DC unit for their battery management setup and report back. This would be great if effective, because I could keep my main IBS setup, monitor and controls...which I like.
I may try adding IBS’ new add-on DC-DC unit for their battery management setup and report back. This would be great if effective, because I could keep my main IBS setup, monitor and controls...which I like.
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A proper Lithium, nearly all problems solved.
Bulk charge at 14.2.
Float at 13.6
Built in charge and temp protection.
5000 cycles vs 1000-ish for AGM
1/3rd the weight
Nearly twice the usable capacity
Charge rate insanely faster
Many dollar signs.
Bulk charge at 14.2.
Float at 13.6
Built in charge and temp protection.
5000 cycles vs 1000-ish for AGM
1/3rd the weight
Nearly twice the usable capacity
Charge rate insanely faster
Many dollar signs.
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Markuson
SILVER Star
- Thread starter
- #56
Hey Tony,
I was thinking you had run into problems with your new Lithium in Baja.
Maybe I misunderstood.
Can you clarify?
If that was resolved...did you ever have a chance to determine performance with a fridge and run-down times during non-engine use/camping, etc?
It just drained constant from usage from a big ass fridge, charging drone/phone/ect batteries, and running a 2000W inverter. Mostly the fridge which isn't efficient at all and me just not paying attention.
I'd guess with a more efficient fridge and being more mindful of charging stuff the 100aH Lithium should last 3 or 4 days or so. If you plug in a solar panel, it'll never drain out.
Heat was my main concern since it was mounted in the engine bay. But with 140F intake temps on the way out from the mission, hauling dick through the desert, it never cut power. I also wrapped the battery in gold heat reflecting tape.
After a couple hours of driving it was fully charged again. An AGM would take at least all day (and then some) to charge back up from just an alternator.
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I believe the diode "solution" is misdirected, and we're addressing a symptom of a larger issue that the diode actually exacerbates.
The root issue here is that AGM's are fundamentally not compatible with the vehicles charging system. To charge and maintain an AGM, requires a different charging "profile". The alternator voltage regulators onboard vehicles are tailored for flooded cell batts, period. Any other architecture of battery is going to be compromised.
This is not really about deep cycle/starting amps/capacity/charge level. It's also not about the low charge level you experience on a trip, and you need more charge, and bigger batts. This is because the batt has already been compromised and cannot effectively hold charge any longer.
Specifically, AGMs and other sealed batts, cannot handle the higher peak voltages from the alternator after initial startup. Flooded cells like this for a quick recovery. And they have much more abilities to handle extraneous voltage and current. Sealed batts, when exposed to this, can quickly overheat and boil. Add the hot underhood temps, with higher than AGM compatible peak voltages... They don't deal with this well as they can't really "out-gas" effectively, without permanent impacts like premature failure of internal cells.
Get yourself some solid normal flooded batts. They don't have to be super duper extra large group 31s either. There's nothing inherently crazy with running small fridges, winches, lights, electronics, etc. With some of these (e.g. winch), you'll want the engine running anyways. And you have a nice generator in the form of the engine to top off for longer stretches. My 2x normal group 27 flooded batts last at least 2 days for a full blown camper with all the house amenities. Lots of lights, water pumps, furnace, electronics. And these lasts many many years in this type of use.
Normal flooded cell batts for the win here because its the right type of battery for the application.
Now if you can isolate the AGM/Gel/Lithium batt cicuit, and have a BMS/solar charger, set to the right profile... that's the trick!
The root issue here is that AGM's are fundamentally not compatible with the vehicles charging system. To charge and maintain an AGM, requires a different charging "profile". The alternator voltage regulators onboard vehicles are tailored for flooded cell batts, period. Any other architecture of battery is going to be compromised.
This is not really about deep cycle/starting amps/capacity/charge level. It's also not about the low charge level you experience on a trip, and you need more charge, and bigger batts. This is because the batt has already been compromised and cannot effectively hold charge any longer.
Specifically, AGMs and other sealed batts, cannot handle the higher peak voltages from the alternator after initial startup. Flooded cells like this for a quick recovery. And they have much more abilities to handle extraneous voltage and current. Sealed batts, when exposed to this, can quickly overheat and boil. Add the hot underhood temps, with higher than AGM compatible peak voltages... They don't deal with this well as they can't really "out-gas" effectively, without permanent impacts like premature failure of internal cells.
Get yourself some solid normal flooded batts. They don't have to be super duper extra large group 31s either. There's nothing inherently crazy with running small fridges, winches, lights, electronics, etc. With some of these (e.g. winch), you'll want the engine running anyways. And you have a nice generator in the form of the engine to top off for longer stretches. My 2x normal group 27 flooded batts last at least 2 days for a full blown camper with all the house amenities. Lots of lights, water pumps, furnace, electronics. And these lasts many many years in this type of use.
Normal flooded cell batts for the win here because its the right type of battery for the application.
Now if you can isolate the AGM/Gel/Lithium batt cicuit, and have a BMS/solar charger, set to the right profile... that's the trick!
Pretty much. But said I've said, if you can swing the cost and it suits your needs (you can't jump your rig off of a lithium (usually) and running a winch off one is a bad idea as they usually can't flood amps like cold start battery though the Battle Born can for short bursts), a Lithium is the way to go for just a power supply battery. It's expensive initially, but cheaper in the long run, lighter, and charges quicker. I don't know why people on here are so adverse to Lithium.
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Well, other than the Battle Born is $1k...
FYI, the BB batts have shown issues too. Not so much in regards to degradation. But they experience a similar issue in that they don't get fully topped off. So you pay lots for 100ah, but in use it's effectively less because the vehicle charging system may actually drag the charge level down over long drives. This is because lithium voltage profile doesn't droop as much over its usable capacity. So minute changes in voltage level represent much bigger charge level differences.
Flooded batt...
Or use a standalone battery system like a Goal Zero that offers way more flexibility. A portable folding solar setup works wonders for extended power. Forget the heavy, complicated, expensive, integrated battery setup.
Or even better and cheaper - Flooded batt, with portable solar charger! Reserve for weeks.
FYI, the BB batts have shown issues too. Not so much in regards to degradation. But they experience a similar issue in that they don't get fully topped off. So you pay lots for 100ah, but in use it's effectively less because the vehicle charging system may actually drag the charge level down over long drives. This is because lithium voltage profile doesn't droop as much over its usable capacity. So minute changes in voltage level represent much bigger charge level differences.
Flooded batt...
Or use a standalone battery system like a Goal Zero that offers way more flexibility. A portable folding solar setup works wonders for extended power. Forget the heavy, complicated, expensive, integrated battery setup.
Or even better and cheaper - Flooded batt, with portable solar charger! Reserve for weeks.
