ecotrek batteries using 6 internal amps

[Davydd]

Originally Posted by booster

I think everyone needs to understand that you can't transfer results and design robustness from the ARV system to all the others. ARV has basically a cost is no object style system and it is very good, and very expensive, compared to what else is being offered by others.

I think you are attributing too much "cost is no objective" to what ARV does. ARV does have a philosophy of do it right as best you can. From my viewpoint after looking at what Roadtrek had and what I have, I suspect ARV's system may be less expensive. My breakdown costs of components were less than what Roadtrek was listing. To me it is clearly simpler and seemingly has more safeguards and user controls for understanding and trouble-shooting.

BTW, after less than a year and a half I am now officially ARV old technology. ARV has simplified there under body battery system in stainless steel battery boxes with Thinsulate insulation and without the steel frame box armor. Anything going out from here on in seemingly looks a lot better, functional and taking up less space than my setup.

[gerrym51]

Originally Posted by Davydd

I think you are attributing too much "cost is no objective" to what ARV does. ARV does have a philosophy of do it right as best you can. From my viewpoint after looking at what Roadtrek had and what I have, I suspect ARV's system may be less expensive. My breakdown costs of components were less than what Roadtrek was listing. To me it is clearly simpler and seemingly has more safeguards and user controls for understanding and trouble-shooting.

BTW, after less than a year and a half I am now officially ARV old technology. ARV has simplified there under body battery system in stainless steel battery boxes with Thinsulate insulation and without the steel frame box armor. Anything going out from here on in seemingly looks a lot better, functional and taking up less space than my setup.

have ARV prices dropped?

[mojoman]

After reading this thread, I'm going to convert my iPhone from Lithium to an AGM battery. Its settled science!

[booster]

IMO, most of the questions and issues brought up about lithium have little to do with the batteries themselves, but in the hardware and software needed to actually use them. The phone companies definitely have an advantage of being able to have big enough volumes to design and build in those systems, where RVs don't. I would rate a phone lithium battery design as more settled and tested than any AGM battery in an RV, so mojoman should be good with his lithium

Many get scared by high cost and possible unknown issues with lithium, when compared to lower cost and known shortcomings of AGM. Whether that is rational or not is individual tolerance, I think. Tesla has shown that well designed systems work well for the masses, but that level of expertise is certainly not prevalent in the RV business yet.

Homebuilts like mojoman, or the others that are being built are usually built with specific wants and needs, and well understood by the owners, so the chance of success are probably substantially higher than many of the factory installs, that are dropped on the masses.

[gerrym51]

Originally Posted by mojoman

After reading this thread, I'm going to convert my iPhone from Lithium to an AGM battery. Its settled science!

lol-why-nothing wrong with lithium batteries themselves-but using 6 amps per hour internally is

[Davydd]

Originally Posted by gerrym51

have ARV prices dropped?

I have no idea. I doubt it. As one ARV buyer said to me, I was lucky to buy when I did because they know their costs and margins better. They also have all the work they can or desire to handle it appears. I went with the philosophy of if you have to ask then you can't afford it.

Truth is I knew ahead of time that if I wanted a Class B that would satisfy my wants, desires, ideas and correct annoying peeves that Advanced RV would be the only one that could deliver. Custom builders like Sportsmobile couldn't do it. Roadtrek was never in consideration because I've always considered their Sprinter floor plans as major design flaws I could not accept especially after already owning two more functional Class B designs I was trying to improve on. I wasn't in the market for another dealer marketed model that has to compromise to compete in the market. I would have just kept my Great West Van Legend as it was still the best of the dealer models, IMO. The Promasters could not improve on my 2-person touring expectations. But this is all personal preferences and a subject for a different thread.

We've beat the Roadtrek battery depletion problem to death here. Any new developments on the Facebook Owner's Group? I still have this gnawing feeling that the original premise letter is flawed information. Or let's say I find it improbable 24ah per hour could be evaporating for no useable reason. If that were true you would think there would be a user uprising.

[cruising7388]

Originally Posted by booster

I think everyone needs to understand that you can't transfer results and design robustness from the ARV system to all the others. ARV has basically a cost is no object style system and it is very good, and very expensive, compared to what else is being offered by others.

That said, the information that davydd has posted about how many AGM batteries would be needed to be equivalent to his lithiums is not how I would portray the same comparison. Most of the time, the comparisons are done, like davydd has done, assuming the AGMs can only be discharged to 50% or they fail very quickly. We had a very good discussion of this on the board a few months ago, and the actual data we were able to find was very interesting, to be sure. Yes, you get about 1/2 the number of total recharge cycles at 80% discharge when compared to 50%, but if you look at the total number of amp hours in and out over the life of the battery, which is what really counts, the difference drops to only 10%. If you have even a moderate number of shallow cycles, the 10% also disappears. The same data indicated lithiums to be more susceptible to losing cycle life, based on total amp hours in and out over the life of the battery, do to deep discharges, than AGM, although they still have considerably longer life than AGMs.

Based on that information, I think the more realistic and fair comparison would use the 80% discharge capacity of the AGM batteries. That would make 800ah of AGM batteries have 640ah usable, which is about the same as davydd has usable in his setup. That could be four big six volt AGMs that would weigh about 500#. Davydd's batteries will be lighter, but he also has a very heavy insulated frame and case, so the difference is reduced some.

Using the 80% discharge also allows faster recovery of daily use, as you are in the high acceptance rate area of the battery more of the time, basically from 80% DOD to about 20% DOD. Lithium still wins here as they stay in the high acceptance until almost full.

Using the 80% discharge does not change the fact that you need to get a full charge on the AGM batteries every 70-10 cycles or so, and should be done with charging methods much better than the ones Roadtrek, or most others, offers. You need good equipment and at least 12 hours of reliable charging power to do it. IMO, this is the biggest downside of the AGMs.

The lithium systems are getting better, and cheaper, and likely will be taking over most of the RV market, unless there is something new showing up, but most of the RV manufacturers are still learning how build them. Roadtrek is a prime example of this, as they have had a very rough rollout of their lithium systems. Of course, the e-trek AGM systems had/have lots of issues, too.

I would love to have a lithium system, but it would need to be of the ARV level of durability, although with simplified systems. It is getting to be closer all the time to having the parts available to put together a basic, reliable lithium system off the shelf, which should change things a bunch for the manufacturers.

Your analysis of the real world operating life of an AGM seems spot on but doesn't it have to be considered in the larger context of real world RV use?

The worst case scenario for a lithium battery with a BMS is that it will shut down to protect the battery before the depth of discharge causes degradation. Not so with the AGM which as a practical matter in RV applications is often subjected to discharge depth much higher than 50% resulting in permanent and cumulative degradation of its usable life span.

Ironically, even the set point for the VoltStart to engage is not 50% DOD. Unless it's a misprint in the Roadtrek VoltStart exposition, this setpoint is 11.2 volts which is the practical equivalent of complete discharge. This obviously would create a wider window of operation by the AGM before VoltStart kicks in, but I can't see how this level of discharge can do anything but drive the life of the battery significantly lower than your calculation.

[booster]

Originally Posted by cruising7388

Your analysis of the real world operating life of an AGM seems spot on but doesn't it have to be considered in the larger context of real world RV use?

The worst case scenario for a lithium battery with a BMS is that it will shut down to protect the battery before the depth of discharge causes degradation. Not so with the AGM which as a practical matter in RV applications is often subjected to discharge depth much higher than 50% resulting in permanent and cumulative degradation of its usable life span.

Ironically, even the set point for the VoltStart to engage is not 50% DOD. Unless it's a misprint in the Roadtrek VoltStart exposition, this setpoint is 11.2 volts which is the practical equivalent of complete discharge. This obviously would create a wider window of operation by the AGM before VoltStart kicks in, but I can't see how this level of discharge can do anything but drive the life of the battery significantly lower than your calculation.

Yep, real world is what counts, and that is why it all gets so difficult at times. From what we found in the previously mentioned discussion on cumulative amp hours over life, discharges to 80% down don't really seem to have any real significant penalty, and certainly not the "certain death" claims that have been standard for years. Several in this discussion mentioned the 50% myth, which is pretty accurate, IMO. In the data we saw, even going totally dead wasn't as bad as portrayed, but definitely bad. AGMs don't have a low battery cutout because the RV manufacturers chose not to put one into system probably do to cost. The hardware is available, but the only ones that are any good are based on a shunt based battery monitor. Voltage triggers are nearly useless in many cases.

That said, the Voltstart and the inverter both will trigger off voltage, even though voltage is a bad way to do it. Most would say that AGMs at 11.0 volts are very close to dead, but a small battery bank running at 100 amps to the inverter may only be able to hold 11.0v even when at 80% full, so the Voltstart will kick in without the battery being actually discharged much. Same thing can happen with inverters kicking out, but they are mainly protecting themselves from low voltage problems.

Real world tends to knock the pants off many of the claims and things like setpoints and triggers, and any voltage based reading and trigger on a loaded system is inherently inaccurate.

[mojoman]

6 amps per hour could be all of the controls, control screens,USB plugs, gauges, sensors, etc... and anything else with a transformer or circuit board. I have a similar draw if I turn the power on to everything. I have a switch on every component in my rig, AC and DC to eliminate parasitic losses. That would be a nuisance for most RVers and a higher cost.

[gerrym51]

Originally Posted by mojoman

6 amps per hour could be all of the controls, control screens,USB plugs, gauges, sensors, etc... and anything else with a transformer or circuit board. I have a similar draw if I turn the power on to everything. I have a switch on every component in my rig, AC and DC to eliminate parasitic losses. That would be a nuisance for most RVers and a higher cost.

Roadtrek engineers exact words-battery uses 6 amps internally. what that actually means only roadtrek knows

[cruising7388]

Originally Posted by booster

Yep, real world is what counts, and that is why it all gets so difficult at times. From what we found in the previously mentioned discussion on cumulative amp hours over life, discharges to 80% down don't really seem to have any real significant penalty, and certainly not the "certain death" claims that have been standard for years. Several in this discussion mentioned the 50% myth, which is pretty accurate, IMO. In the data we saw, even going totally dead wasn't as bad as portrayed, but definitely bad.

Real world tends to knock the pants off many of the claims and things like setpoints and triggers, and any voltage based reading and trigger on a loaded system is inherently inaccurate.

I think there are two additional factors that affect the bottom line regarding the longevity of batteries subjected to high levels of discharge:

1. Timely recharge before the amorphous lead sulfate degrades into a crystals that resist the conversion back into lead. The rule of thumb should be the sooner the better.

2. Physical stability. IMO, a really bad thing is to subject the discharged battery to any vibration that encourages the lead sulfate to slough off the plate and sink to the bottom of the case where it will never be recovered and in the worst case will short out the plates. The unique construction of an AGM may mitigate this but doesn't eliminate it.

That said, your skepticism regarding conventional doomsday predictions on highly discharged batteries is well taken. I had a Concord Lifeline 31 AGM battery that (because of my world class propensity to screw up), discharged to a terminal voltage of three volts and didn't discover it until after months after it happened. I couldn't even get my battery charger to recognize it. So I replaced it. But subsequently, I tried using a fixed variable voltage power supply on it just for kicks and surprisingly it came back to life. I then put it through a normal charging process and not only did it rejuvenate itself, it shows a perfectly respectable discharge curve under a carbon pile load tester. Who wudda thunk?

[gregmchugh]

Originally Posted by cruising7388

That said, your skepticism regarding conventional doomsday predictions on highly discharged batteries is well taken. I had a Concord Lifeline 31 AGM battery that (because of my world class propensity to screw up), discharged to a terminal voltage of three volts and didn't discover it until after months after it happened. I couldn't even get my battery charger to recognize it. So I replaced it. But subsequently, I tried using a fixed variable voltage power supply on it just for kicks and surprisingly it came back to life. I then put it through a normal charging process and not only did it rejuvenate itself, it shows a perfectly respectable discharge curve under a carbon pile load tester. Who wudda thunk?

The battery lifetime spec in the Lifeline Technical Manual show 375 cycles at 100% discharge and the manual describes the process to use to revive a fully discharged battery.

For reference, 1000 cycles at 50% discharge and 550 cycles at 80% discharge.

[cruising7388]

Originally Posted by gregmchugh

The battery lifetime spec in the Lifeline Technical Manual show 375 cycles at 100% discharge and the manual describes the process to use to revive a fully discharged battery.

For reference, 1000 cycles at 50% discharge and 550 cycles at 80% discharge.

I don't think the 375 cycles at 100% spec includes driving the battery down to 3 volts and leaving it that way for six months.

I do think their batteries are awesome. The replacement I got is their upgraded 31 with a bump up in the AH capacity. One caveat, however: don't misplace or lose the cable attachment bolts - they're metric threaded. Trust me, I've been there.

[wincrasher]

LOL. As if Roadtrek has any electrical engineers on staff. None credentialed as far as I can tell. Please name one if anyone can.

All they do is trial and error experimentation at their customers expense. This is just more of the same. 6 amps draw per battery without any equipment running?!

The top line CS with the big bank and all the equipment tops $180k and they still are having issues. I can't see not considering the ARV for $40k more. It certainly would be worth the 12 month wait if postings like this are any consideration.

FWIW, my cheapo, bare bones lithium setup is running strong with no issues. Simplicity is bliss IMNSHO.

FitRV is about to unleash their Nations second alternator setup in their Travato, and I expect, a conversion to lithium. I hope they are removing their Onan and installing a big battery bank in that spot. I'm dying to see what they do and how it will work.

[gerrym51]

Originally Posted by wincrasher

LOL. As if Roadtrek has any electrical engineers on staff. None credentialed as far as I can tell. Please name one if anyone can.

All they do is trial and error experimentation at their customers expense. This is just more of the same. 6 amps draw per battery without any equipment running?!

The top line CS with the big bank and all the equipment tops $180k and they still are having issues. I can't see not considering the ARV for $40k more. It certainly would be worth the 12 month wait if postings like this are any consideration.

FWIW, my cheapo, bare bones lithium setup is running strong with no issues. Simplicity is bliss IMNSHO.

FitRV is about to unleash their Nations second alternator setup in their Travato, and I expect, a conversion to lithium. I hope they are removing their Onan and installing a big battery bank in that spot. I'm dying to see what they do and how it will work.

Ron you are funny- i must point out you live in a moderate climate zone

[cruising7388]

Originally Posted by wincrasher

LOL. As if Roadtrek has any electrical engineers on staff. None credentialed as far as I can tell. Please name one if anyone can.

All they do is trial and error experimentation at their customers expense. This is just more of the same. 6 amps draw per battery without any equipment running?!

The top line CS with the big bank and all the equipment tops $180k and they still are having issues. I can't see not considering the ARV for $40k more. It certainly would be worth the 12 month wait if postings like this are any consideration.

FWIW, my cheapo, bare bones lithium setup is running strong with no issues. Simplicity is bliss IMNSHO.


FitRV is about to unleash their Nations second alternator setup in their Travato, and I expect, a conversion to lithium. I hope they are removing their Onan and installing a big battery bank in that spot. I'm dying to see what they do and how it will work.

Well, I'm basking in the pleasure of having the opportunity to even just converse with someone for whom 40k is just chump change.

Can you provide details regarding the problems with the CS? Mechanical? Electrical?

Surfed through your blog. Awesome. Man, that's as good as it gets!

[wincrasher]

Cruising - nothing specific to the CS, it's just the most equivalent to the ARV. All the problems I've heard of are related to the Ecotrek as you'll see if you wade thru this thread on the batteries.

Gerry - when or if I installl heaters on my batteries, they'll draw a lot less than 6 amps per battery! Plus, they'll be on a switch!

[Davydd]

Hey, I have been accused of considering $40K chump change around here. You've been conversing with me.

BTW, There is way more in the $40K than just batteries. It is across the board in every aspect you desire to consider and compare.

[gerrym51]

Originally Posted by wincrasher

Cruising - nothing specific to the CS, it's just the most equivalent to the ARV. All the problems I've heard of are related to the Ecotrek as you'll see if you wade thru this thread on the batteries.

Gerry - when or if I installl heaters on my batteries, they'll draw a lot less than 6 amps per battery! Plus, they'll be on a switch!

Ron-you'll have bought another rv by then

[booster]

Another thread got to talking about warranties and such, and the Ecotrek battery drain issue came back to mind in relation the the value of a long warranty if there is no admission of a problem existing.

Has anyone heard anything lately in regards to if the 6 amps of parasitic drain, per module, was accurate, or if Roadtrek has said what they are going to do to fix the issue?