Advancing Alvar

[wincrasher]

I think you guys just enjoy pushing Davydd's buttons.

If you don't like this horrible, kludgy ARV system, you can always buy a Roadtrek and save a couple bucks. I hear they're sorta working now and have unbelievable performance for every possible environmental situation now that they've spliced in an AGM battery!

[booster]

Originally Posted by wincrasher

I think you guys just enjoy pushing Davydd's buttons.

And of course we all know that you would never do that!

[gregmchugh]

Originally Posted by wincrasher

I think you guys just enjoy pushing Davydd's buttons.

If you don't like this horrible, kludgy ARV system, you can always buy a Roadtrek and save a couple bucks. I hear they're sorta working now and have unbelievable performance for every possible environmental situation now that they've spliced in an AGM battery!

Or save even a lot more bucks and buy one of those state-of-art Winnebago Eras. I hear it comes with one of those fancy Onan propane generators, a state-of-art converter/charger, and you can even get a cool electrical upgrade from the factory, a second one of those AGM batteries. Oh, wait, I guess my 08 Roadtrek RS is equipped with those things, except for that converter/charger, I just have a lowly inverter/charger... I guess I may just live with what I have... 😀

[avanti]

OK, gang, be nice.

[gregmchugh]

Originally Posted by avanti

OK, gang, be nice.

Well that would surely be a change of pace for the New Year...😳

[Davydd]

Originally Posted by wincrasher

I think you guys just enjoy pushing Davydd's buttons.

If you don't like this horrible, kludgy ARV system, you can always buy a Roadtrek and save a couple bucks. I hear they're sorta working now and have unbelievable performance for every possible environmental situation now that they've spliced in an AGM battery!

I just don't have an AGM battery now according to the collective intelligence to solve my non-existent problem. I fear I may have to ask for a half-dillion electrical diagrams now to figure out a kludge.

[Davydd]

Originally Posted by pattonsr

Davydd,

Have a stiff drink. You are starting to sound like Donald Trump tossing out insults..

The Donald is getting results.

[Davydd]

Originally Posted by booster

Davydd, just reread post #893. You sound exactly like what you always criticize.

Real world example at my house. If I had your ARV, it would not fit in the heated garage so I couldn't keep the batteries warm. I also wouldn't want it in the driveway all the time in the way of the snow clearing, etc. I also hate having cords draped through the snow all the time to get chewed up in the snow blower. Great, get lithium so you don't have to have them on charge all winter because of the low self discharge rate. Oh, wait, you still need to keep it plugged in all the time if you don't want to wait for warm weather to thaw it out, or beg someone to park it inside for you.

Not leaving it in the driveway and no cord are things I want, you obviously think otherwise. They are my choice of things not to compromise. Should I now go on a tirade about how silly and and unintelligent you are to accept them?

Personally, there is no way I would ever consider that having to put a heater on the ground under a $200K van to thaw the batteries could be considered an OK procedure. That is a Rube Goldberg.

Sideline, the no power when in battery shutoff was said to be no different a compromise than being winterized. I would only agree with that if it is possible to carry a jug of electricity to use to run the heat and lights when needed, like you can with water for it's purposes.

Here again you have an answer for everything. If I said I enjoyed brewing a cup of coffee anytime anywhere or needed to reheat it a quick 30 seconds in the microwave at 6 AM in the morning during campground quiet hours, your predicted answer would be I don't drink coffee.

[tinman22]

David, I cannot tell you just how much I have enjoyed reading your first-hand information regarding Alvar and AVR. Your research, testing, and honest owner/driver reports are most welcome to so many of us who may be interested in buying AVR - the detracters and naysayers, once excersing their thoughts on new strategies/ideas/inventions, seem to have become the usual negates that surface when utilizing non face-to-face discussions.
May this be a much better year for all of us!
Question 1: Will the 4x4 also allow for the VB Air Suspension?
Question 2: Seems to be much exposure of underfloor systems - have you driven much on gravel/unimproved roadways? And, with what results?
My hat's off to you, David.

[Applegater]

Couldn't agee more with tinman 22. Looking forward to picking up our new ARV in two weeks.

[gregmchugh]

Very interesting, I have not seen any ARV detractors or naysayers on this thread, in fact I don't recall anyone saying anything negative about ARV anywhere in the Class B Forum. Many would surely want an ARV of their own if they were able and willing to spend the money and wait for the delivery. Maybe you are taking opinionated discussions of what features would be desirable for different individuals as somehow being negative about ARV.

[Davydd]

Originally Posted by tinman22

David, I cannot tell you just how much I have enjoyed reading your first-hand information regarding Alvar and AVR. Your research, testing, and honest owner/driver reports are most welcome to so many of us who may be interested in buying AVR - the detracters and naysayers, once excersing their thoughts on new strategies/ideas/inventions, seem to have become the usual negates that surface when utilizing non face-to-face discussions.
May this be a much better year for all of us!
Question 1: Will the 4x4 also allow for the VB Air Suspension?
Question 2: Seems to be much exposure of underfloor systems - have you driven much on gravel/unimproved roadways? And, with what results?
My hat's off to you/ David.

Thank you. I am a willing face to facer. I am already scheduled in for four Class B rallies this year.

1) The 4x4 works with VB Air Suspension.

2) I have driven a little bit on gravel roads in northern Minnesota driving in the 40 - 50 mph range like the 24 mile gravel Sawbill Trail. Everything is pretty well protected especially the batteries with a substantial skid plate. ARV takes a lot of care on the underside. I think that comes from Mike N's neat freak nature. He gets involved with the details as if he were building it for himself. Example: At the last minute he told his team to add a padded leather bumper to the end of my bed because he felt someone could bump their shins on the wood base. Every customer gets that treatment.

[skagitstan]

I have a question and possible idea about getting lithiums warmed up for use.

This is mainly out of curiosity, since I'm building my own conversion on a Transit base, with AGMs as the house battery...at least until I figure lithium tech is much more mature.

Anyways, the question is if the car is also dependent on the house lithium system, or does it keep the stock Sprinter lead battery?

If the systems are split, I'd think it would be easy enough to start the van, and run a heater system (maybe even heat diverted/pumped from the exhaust) powered by the car electrics to warm up the house system.

Does that seem like a possible solution, or a problem, or something I'm completely missing the boat about???

Stan

[Jostalli]

Or put the batteries inside. Start the van and turn on the heat. I have 16 160ah cells installed under the sofa sleeper.

[skagitstan]

Yes, of course.
My AGMs are inside. So is my entire plumbing system (except for drains).
I'm building specifically for boonie operation with sub 0C a common occurance.
But I'm guessing ARV wants to keep space inside more open, or more storage than I need.

[booster]

The system of using running the engine to generate heat for the batteries, from electric, water, etc that Stan suggests is exactly what has been proposed by many of us, and IMO would be easy to do. Some would call it Rube Goldberg or naysaying, though.

[Davydd]

So you know what you might be dealing with, my lithium ion 800ah - 16 3.2v cells measure in a contiguous block about 19" x 24-1/2" x 9-1/2". Then you add connectors, wire, buss bars and clearance space. The usable battery capacity at 80% would be equivalent to about 13 100ah 12v AGM batteries with a usable 50% capacity. You can adjust your own numbers if you would like. Some people think they can discharge both batteries more. The lithium ion battery bank weighs about 227 lbs. The AGMs would weigh close to 900 lbs. Equivalent AGMs ain't going to happen space and weight wise in a B. I've eliminated an Onan generator and the batteries fit easily in that abandoned spot.

I guess I'll say it again. Worrying about lithium ion batteries going cold on you while in use would be a major space sacrifice in a B. Sorry I am the only one here with any actual experience in lithium ion battery use. You tell me if you think something you may never have to do as I think in Minnesota is worth the space sacrifice in an already small B.

Here is what you would be dealing with. It took me 6 days with no heat on my batteries that would normally be on to prevent shut down other than inherent heat from charging and discharging to force the batteries to shut down as designed. Those 6 days ranged from a minus 5 to a plus 27 degrees. Never above freezing. It wasn't until I stopped, arrived home and parked the final two days leaving the B unused did they finally go cold.

Is that naysaying or just some common sense real facts?

Skagistan, If 0 centigrade is seriously all you would have to worry about then you have nothing to fear. Your batteries would never go cold in use. Probably not in cold storage either.

[skagitstan]

It could just be an issue of different application needs.

To be clear, I'm not knocking ARV. If I hadn't wanted the challenge of "rolling my own", and the long lead times, I would likely have been in serious discussions with them.

I've come late to this discussion, so I apologize if I'm just beating a dead horse.
As a systems engineer, I worry about failure modes.

I would love to take advantage of the weight and energy density advantages of lithium.
I chose not to use them because of the as yet finicky temperature and charging/balance issues. The technology is just not really mature or as well characterized as AGMs.

I expect to be camping, and snow backpacking for over a week on occasion with no power source except the solar, house batteries,car battery, propane, and fuel/engine power generation.

Given the requirement that current day lithiums require a heat source (internal or external) to avoid low temperature charging problems, I am concerned that a self heating scheme with no external alternate power source, presents a clear potential failure mode...especially with externally mounted batteries. This is the design issue that I think folks are discussing. If it isn't, well I'll just crawl back into my cave.

I would hate to come back to my camper to find I had limited or no house power remaining because the system had shut down, the van buried in a snow drift, and no external heat source to bootstrap the lithiums back to a usable/chargable state.

Obviously this isn't an issue IF you never expect to be away in the cold long enough to hit the self-heating discharge limit. Since I'm not in a position to know how rapidly your external battery pack dissipates energy under your realistic extremes, I cannot know if it is an issue for your use.

So, given the likelihood that I will hit some unpredictable cold extremes with Annie, I am just wondering what sort of simple backup/reboot energy source could be used in a lithium based house battery design. It occured to me that an exhaust waste heat scavanger could be such a simple backup.

BTW, it's been well below 0C at our house for the last week, and we're not in a particularly cold locale. I used the 0C number because below that temperature you WILL eventually need some heating source for the battery pack.

Stan

[Davydd]

I was commenting to your original statement of 0C as the lowest. Batteries in use are warmer than the air temperature and it is the battery temperature that triggers a shut down not the air temperature. The ARV shutdown disconnect is arbitrarily designed to happen. If you don't put that in your system your batteries will not disconnect. In theory you could be gone for the week and temperatures could go way below freezing and if they came back up so would your battery temperature. It had to get down to -5F for my battery to drop to 32F (freezing).

[Aeronie]

Originally Posted by tinman22

David, I cannot tell you just how much I have enjoyed reading your first-hand information regarding Alvar and AVR. Your research, testing, and honest owner/driver reports are most welcome to so many of us who may be interested in buying AVR - the detracters and naysayers, once excersing their thoughts on new strategies/ideas/inventions, seem to have become the usual negates that surface when utilizing non face-to-face discussions.
May this be a much better year for all of us!
Question 1: Will the 4x4 also allow for the VB Air Suspension?
Question 2: Seems to be much exposure of underfloor systems - have you driven much on gravel/unimproved roadways? And, with what results?
My hat's off to you, David.

Tinman, I have an ARV and I live in Vermont. Home of corduroy roads. I do most of my driving on unpaved roads and I've had no issues. I've had my ARV for 6 months now. As Davydd has said, Mike N's is very particular about the underside, not just the inside.