A different lithium battery heater setup

[gregmchugh]

Originally Posted by wincrasher

Greg, I don't think the issue is the batteries generating any appreciable heat while in use. The insulated casing keeps the generated heat from the pads inside, but also shields the batteries from summer heat outside.

It appears that it works well enough not to need a liquid cooling system like the electric cars. Davydd's been to some really hot places and hasn't reported any high temp alarms. How hot is too hot? There's alot of debate about that.

Technomadia sat in the desert heat for weeks at a time and did essentially nothing to mitigate baking their batteries.

I agree that the over heat issue may be a non issue and that a significant amount of insulation may be ideal for both summer and winter. I am sure Davydd can provide the max temps his batteries have seen so far but he seems to avoid really hot weather so it may not represent worst case for summer in the southwest.

[booster]

The "rules" as they seem to be stated now talk about 1/2 the life for every 10*C above normal, or just under a 100*F for the first halving, 110* area for the second. Of course to get max damage the heat has to be pretty constant also, I think.

I would also think that davydd's use would not be much of an issue with heat, as he goes only where he doesn't even feel the need for air conditioning (we are similar).

I do think it may turn into an issue for some hot climate folks, though. If you are in 105* heat and running the AC on batteries with fast recharges off the engine generator so they generate more heat, you could get quite warm, especially if the batteries are underneath where engine, exhaust, hot pavement could max it worse. I would think if you were in those conditions a lot, you could hit the 1/4 life level, but if you had AGMs, they would suffer about the same % loss in cycles.

I think only time will tell if lithium are more, or less, susceptible to heat damage than the initial information is stating. Still too new to know a lot about actual real world life, in general.

[Davydd]

Originally Posted by booster

The lady on Yahoo just posted that Roadtrek confirmed that the batteries only will heat off the engine generator, if they are in cold shutdown. Once warm if they are on and the inverter on, they will then heat off shore power. Stated 40 watts (200ah pack) and 2 hours to heat from -13C (8*F). I assume while you are driving to warm the batteries the engine generator would be supplying the coach, or you would have no frig, etc. If it was -20*F, I wonder if they would ever get warm? You would need to run the engine overnight.


Just don't go anywhere closer than 2 hours if want shore power to charge, I guess.

I would hope they change this, though, as with AGM there, it should be easy to do.

Maybe a battery charger on the engine generator output so could warm when AC available to preheat before leaving.

OK let's forget I told you if you know what is going on an ARV's battery will never go cold as long as there are no system failures. So I won't carry around two AGM batteries for a nuisance rather than a catastrophe that Roadtrek evidently built in. That is the same to me as carrying a spare tire I haven't needed for 160,000 plus RV miles. Crap now you tell me shore power won't bring a Roadtrek back unless you start out and remain plugged in. THAT IS WHAT I TOLD YOU I DO! Now you say run your Roadtrek engine overnight to heat the batteries. Don't you find that to be a little bit asinine after I said a little bitty 1500w ceramic cube heater would do the job faster in -5 deg F. weather? I know for a fact. Not armchair speculation. It takes energy one way or another to produce heat. 15a plug ins are available everywhere and cheaper than overnight gas or diesel or belying the fact one could drive to warm weather in that time and forgo the AGMs.

OK, I'm irrational. Oh yeah. You guys better get some experience and knowledge under your belt before further bloviating the praise of Roadtreks solution because it sounds more like a Rube Goldberg solution to prevent a catastrophe they haven't fixed. Do they have individual cell temperature monitoring with auto shut down protection? Can they maintain a recommended 41 degree temperature when it is well below zero with hands free automatic operation on the road or plugged into shore power? We already know they can't program their Voltstart and I can tell you right now if they are running an air conditioner they can blow thru their 10% SOC cushion before it catches, starts and charges.

I have been camping from 0 to 90 degrees on this current trip with no problems at either end. Never below 41 degrees and I don't think over 100. No I will not ever be going to Death Valley, Palm Springs, Joshua Tree, the Salton Sea or Arizona in the summer. February is fine. I enjoyed a fine lunch today high in the mountains where you meet the snow in Idyllwild, CA. It was 64 degrees. I

[booster]

Wow, now davydd can get all cranked up when we are talking about how the Zion works, and it's possible weaknesses, and somehow he thinks we are attacking him????

Time for the tin foil hats, I think.

[gregmchugh]

Davydd has made it pretty clear he thinks we have no common sense, our conversations are inane, and we should just keep quiet and simply never suggest that there is a feature that anyone else could really need that he doesn't already have on his van.

Yet, he cannot resist reading and responding to our inane posts and our nonsensical thoughts rather than just ignoring them.

Reminds me of a bathroom stall poem from my adolescence...

People who write on bathroom walls, roll their sh*t in little balls.
People who read these words of wit, eat these little balls of sh*t.

[Davydd]

You all forget you were giving me **** with personal comments about me and about ARV's cold battery recovery design and then it turned out you all really didn't know **** about Roadtrek's. Roll that up in a ball and swallow it.

Until you guys actually put money where your mouth is and actually buy a lithium ion battery system and get out on the road in below zero weather I find your opinions full of it.

Greg, At least you have admitted your comments are inane and nonsensical. How can I ignore that?

[gregmchugh]

Well, I am surely humble enough to admit that I am not always the brightest one many times here but I am at least willing to admit that what works for me may not be ideal for everyone else and I know that you can very well understand how something works or doesn't work without owning it.

I don't feel any need to upgrade my 08 RS that still has two wet cell house batteries, a Tripp-Lite inverter, a loud Onan, and no solar. I expect I will do the big upgrade to AGM batteries when these wet cells finally die. All works fine for me...

In terms of understanding how the Roadtrek systems work, that is simply a matter of figuring out the design from the outside with conflicting information coming from Roadtrek on many items and reports coming from owners with various van configurations. Two weeks ago they stated the batteries could be warmed up from either the engine generator or shore power and now they are saying only from the engine generator. Just an intellectual puzzle to keep my retired engineer brain active. I have no horse in the race.

In terms of ARV vs Roadtrek, this is apples vs oranges. Different customer base, different company strategies and objectives, clearly different personalities involved. I think ARV is clearly doing a wonderful job of getting customers a custom van they will love but it doesn't come cheap or fast. Roadtrek is doing what they feel makes sense to stay competitive in a different market segment and no reason to not expect that they will sort out the current issues at some point. Is ARV more perfect than the other companies? Is Roadtrek a lot worse than other companies? Well, I took the factory tour at Roadtrek yesterday and they appear to be working at capacity to fill their orders just like ARV is doing. They both have plenty of customers waiting in line to get a van...

Now prepared for the slew of negative comments about Roadtrek...

[booster]

I just seem to find it very interesting the davydd is the one complaining about getting digs about his RV and disparaging personal comments about him.

All one has to do is read the last few posts here and see the irony in that.

[gregmchugh]

I have given up on increasing some peoples self awareness, it just ain't in their DNA...

[mojoman]

I'm almost done building a 900AH lithium power center for my build. I have spent many hours reviewing other system designs and their shortcomings and the parameters these batteries work in. I developed a system that will accommodate most any environment or situation. It just takes allot more wire, equipment and labor to do so. Understand why most MFG design their systems like they do because it would have been much easier and cheaper to do it their way. I don't care for a centrally controlled system as one malfunction shuts everything down. I opted for separate,by-passable automated controls that give me more operational options. Most people wouldn't want to deal with operating the system but I like having the extra control more than a reduction in flexibility. The charging parameters for my cells are 32-113f .

[gregmchugh]

Originally Posted by mojoman

I'm almost done building a 900AH lithium power center for my build. I have spent many hours reviewing other system designs and their shortcomings and the parameters these batteries work in. I developed a system that will accommodate most any environment or situation. It just takes allot more wire, equipment and labor to do so. Understand why most MFG design their systems like they do because it would have been much easier and cheaper to do it their way. I don't care for a centrally controlled system as one malfunction shuts everything down. I opted for separate,by-passable automated controls that give me more operational options. Most people wouldn't want to deal with operating the system but I like having the extra control more than a reduction in flexibility. The charging parameters for my cells are 32-113f .

Very good, are you using an off-the-shelf BMS? Battery heaters? More detail would be of interest to me...

[avanti]

Originally Posted by mojoman

I don't care for a centrally controlled system as one malfunction shuts everything down. I opted for separate,by-passable automated controls that give me more operational options. Most people wouldn't want to deal with operating the system but I like having the extra control more than a reduction in flexibility..

I agree. I am all for automation in the cause of safety and convenience, but there is no good reason to put all your eggs in one automation controller basket. Their excessive reliance on the Silverleaf controller was one of the few things I disliked about ARVs design when we evaluated it, but it was a big one for me. Just as an example, in a B-van, having the heaters controlled by a central system rather than a dedicated thermostat is just not worth the benefits accrued. The same logic applies to most other systems--automate the functions but don't centralize the controls. No need for a single point of failure.

[booster]

Put me in the same camp, I would want enough automation that I wouldn't have to monitor stuff by hand all the time, but let the different systems run themselves. 3 charging sources that can easily have their own automatic, non related controls, aren't all that much. Rarely used heaters, have a light that tells you the batteries are cold and a switch to run a simple connection to engine and/or shore power.

We have separate systems and have under 15ah per day parasitic load compared to 100ah or more on the full blown systems, and if one dies, the others still work. All the pieces are off the shelf stuff, so easy to fix if they fail on the road.

[gregmchugh]

I am also in the non-automated camp or at least having manual backup available. But this really only works well for us geeks. My guess is that the average customer just won't be doing what you need to do to monitor and control the systems when they get as complex as these new high end high tech vans.

[wincrasher]

Huh?

You all go on for ages about wanting thermal protections, and cooling systems and multiple methods for heating and for charging, but you want it all manual? A bank of switches would make you happy instead of a Silverleaf type system? LOL!

I am fairly certain if you want to spring $200k+ for an ARV, Mike would be more than happy to make a few tweeks to the circuits for powering the heating pads, or other such redundancies that would make you happy. After all, you'd be paying for such changes. Would JH at Roadtrek?

BTW, I don't leave my welfare-grade Winnebago out in the weather such that it would experience a complete cold shutdown. I doubt I'd sit an ARV outside, unattended and let that happen to it. You really should already have a heated garage space if you are going to contemplate such an expensive RV. Just to protect it's aesthetics and residual value if for no other reason.

[booster]

Not manual for the everyday stuff, but they can be automatic and separated so if one dies the others still work and the bad one can be replaced easily. Charging systems are that way now for many of us. For the heaters, which would be a fairly rare, and be able to be anticipated, a manual setup would be fine for us, and more desirable than the Silverleaf and a bank of relays. But that is just us.

I thought someone had asked ARV if they would do a less automated setup and were told the wouldn't. Maybe just imagined it.

[wincrasher]

It is a standard feature. Doubt they'd just eliminate it. That would be a big project since it's the heart of their system. But add to it? I'm sure it depends largely on the request and the $.

[gregmchugh]

ARV gives you enough information to monitor the operation of the system which I personally would want. Roadtrek offers no option to have any information at all about the operation of the system. For people who do not want to be flying blind they have no option to do otherwise. They have an interface to a touch screen display that was included in some early deliveries. Hopefully they have a plan to provide it at some point at least as a diagnostic tool for dealers if not as an option for owners. As I said, if they want to automate everything I can live with that if they give me info and have some manual backup options.

[avanti]

To be concrete, here is the custom control panel that I designed and GWV build for us:
control panel1.jpg
The Paneltronics console is ideal, at least for us. I gave the selection of circuit grouping a lot of though. It provides direct control of ALL DC loads (media, telecom, fridge, propane solenoid etc), and you can see at a glance what is on and what is off (there are lights). When all the switches are off, there are NO parasitic loads except for the gas detectors. I disagree that this is only good for geeks. In my experience it is just the opposite. In our old van, DW was constantly trying to memorize the sequence of obscure menu commands to turn the inverter (for example) on or off. Now, she happily just flips a clearly-labeled switch. Yes, DavyDD can afford to leave his inverter on 24/7, but for most of us, the ability to directly monitor and control various loads has a lot of value.

As for thermal protection, etc.: I totally want those things to be automated, and a lot of other stuff, too. I just don't want one massive centralized control system. My reasons involve both robustness and usability.

[avanti]

Originally Posted by gregmchugh

ARV gives you enough information to monitor the operation of the system which I personally would want. Roadtrek offers no option to have any information at all about the operation of the system. For people who do not want to be flying blind they have no option to do otherwise.

I agree with this as well. In fact, I am working on centralized status monitor system that shows all kinds of status information on our Sprinter's nav screen. But, it will be just display and warning--separate from control.

I am not at all arguing for avoiding automation or the sensible application of technology. I am arguing against gratuitous centralization.