Mike Wendlends lithium batteries

[Davydd]

I do want to test in the BLM land desert near Quartzsite in February to see how all the systems work.

Edit: The more I think about this, I don't think I could sit long enough to test the systems to the limit. I know my wife couldn't. We would be up and about driving somewhere and I don't think we could last more than two days in one place like that.

[markopolo]

I deleted the last few posts mentioning Mike Wendland. He's not active on this forum so unlikely to see the post and get a chance to respond.
Bikerbill you are definitely welcome to start a topic about the Webasto unit.

Gerry posted:

william-webasto-fast heat slow hot water.

Alde-fast hot water slow heat.

That would be good info made more widely available if that is affecting some users. We could focus on finding solutions and that would be really beneficial for others having the same issues.

Needs to be in a new topic though.

[markopolo]

I just read through the blog post on the Roadtreking site and realized that it doesn't mention what type of lithium batteries Roadtrek are testing in that rig. Advanced RV, for example notes that their's are "lithium iron" which is also known as LiFePO 4.

Also, getting back to the watts. You can't express battery capacity in watts.

You can express battery capacity in watt-hours but, with lead acid batteries, doing so requires that you specify the Amp hour rating and the voltage to have any idea of the batteries actual capacity. Lead acid batteries include wet-cell, AGM & Gel etc.

Here are the specifications of a Trojan model 31-AGM battery:

2-Hr Rate: 65 Ah (approx 32.5 amps delivered continuously for 2 hours)
5-Hr Rate: 82 Ah (approx 16.4 amps delivered continuously for 5 hours)
10-Hr Rate: 92 Ah (approx 9.2 amps delivered continuously for 10 hours)
20-Hr Rate: 100 Ah (approx 5 amps delivered continuously for 20 hours)
48-Hr Rate: 107 Ah (approx 2.23 amps delivered continuously for 48 hours)
72-Hr Rate: 109 Ah (approx 1.51 amps delivered continuously for 72 hours)
100-Hr Rate: 111 Ah (approx 1.11 amps delivered continuously for 100 hours)
Capacity at 25 Amps constant draw: 177 Minutes

Watt-hour calculation:
using 2-Hr Rate: 65 Ah x 12 volts = 780 watt-hours
using 5-Hr Rate: 82 Ah x 12 volts = 984 watt-hours
using 10-Hr Rate: 92 Ah x 12 volts = 1,104 watt-hours
using 20-Hr Rate: 100 Ah x 12 volts = 1,200 watt-hours
using 48-Hr Rate: 107 Ah x 12 volts = 1,284 watt-hours
using 72-Hr Rate: 109 Ah x 12 volts = 1,308 watt-hours
using 100-Hr Rate: 111 Ah x 12 volts = 1,332 watt-hours

You can clearly see that the watt-hour rating of the battery varies greatly depending on the rate of current drawn from the battery.

Greater load = less watt-hour capacity
Lesser load = greater watt-hour capacity

If watt-hours are used to describe the capacity of a battery then you still need to know the voltage of the battery and the Ah rating chosen to be able to figure out how long the the battery will power a specific load.

LiFePO4 batteries are also affected by the amount of current drawn. Higher current draw = shorter battery runtime. Lower current draw = longer battery runtime. They are not affected as greatly as lead-acid batteries though.

[Belzar]

It will be interesting to see the pricing that RT comes up with. Currently a top of the line CS etrek with all of the options has sticker price of about $150k and retails for mid-$130's or so. I suspect the super-etrek lithium option will be pricey. Add the extended body and 4WD and retail will be north of $150k.

I think the bigger feature than the batteries is moving the AC off the roof. Makes for a much less "industrial" looking van, maybe a little better mileage and gives RT a visual brand distinction, at least till others follow suit.

[booster]

Very good information, Marko, as many folks I run across take the 20 hour rating and apply it to all their use and calculations, and expect accurate state of charge determination. Not unexpectedly, they then wind up with highly inaccurate battery state of charge information when actually using their systems in real life, even if they have a battery monitor, and even if the monitor has Peukert correction (by most accounts that correction isn't very accurate with variable draw rates in RVs). Trimetric doesn't do Peukert for that reason, and bases their state of charge on a continuously resetting calibration point (full battery at 100%) that is determined by the battery charging current (shunt measured) at absorption voltage, which is the best way to do it. Most monitors do this reset, I think, whether they use Peukert or not. Inaccuracies show up when you discharge (Peukert) and recharge (charge efficiency), so the more times you do the cycle without getting full, the less accurate you are on the meter, as you don't hit the recalibrate point. If you are only one or two cycles or so before a full charge, the monitor will be quite accurate unless your use pattern changes a lot. For us, with 375AH of Trojan wet cells, I have upped the setting in the Trimetric and the Blue Sky solar controller to 450AH to be more accurate on them for state of charge. This is totally because of the Peukert, as is shown in the actual capacity at discharge rate that Marko listed. Our discharge rate is even lower than the 100 hour rate shown, which makes sense because we can go considerably longer than 100 hours on batteries, so when we are set at 20 hour rate we are quite inaccurate (we can be over a day off in real use if we use the meter set on 20 hour rate). On recharge, we only go by amps to the batteries, with all the charging systems, so what state of charge things are saying is not a concern for us.

All the fancy stuff above aside, that brings you back to the open circuit voltage to determine state of charge, which can be influenced by any loads that are on, and want the battery resting for an hour at no load to be accurate (a real PITA to do in real life). One step further is the open circuit voltage at a fixed load, which is pretty easy if you have a monitor meter, but you have to make a chart by hand which is also a big PITA, but you only do it once. You will be very accurate with this method once it is in place.

Lithium may make all the Peukert stuff obsolete as, from what we are hearing, there is much lower Peukert with them and the charge efficiency is very consistent. I think it will be very interesting to see if this turns out to be totally correct once some systems get out and are closely monitored and tested

[booster]

Originally Posted by Belzar

It will be interesting to see the pricing that RT comes up with. Currently a top of the line CS etrek with all of the options has sticker price of about $150k and retails for mid-$130's or so. I suspect the super-etrek lithium option will be pricey. Add the extended body and 4WD and retail will be north of $150k.

I think the bigger feature than the batteries is moving the AC off the roof. Makes for a much less "industrial" looking van, maybe a little better mileage and gives RT a visual brand distinction, at least till others follow suit.

Roadtrek has been probably been noticing that Advanced RV is doing well in the uber high end market and wants a piece of that. Margins are almost always much, much better in that kind of market, and margins are what keeps the doors open.

I would not be surprised if a 4 wheel drive totally decked out Roadtrek hits $200K.

[Davydd]

Going by the video of the battery bank they focused on very briefly and searching the web to find a battery that looked similar the closest I could come up with was this one - a LiFePO4 Prismatic cell CALB 3.2v - 180ah battery. Visually the physical size is about right. Whether it is this specific one is a little bit immaterial. Sizes, weight and arrangements would ultimately be similar.

LiFePO4 Prismatic cell CALB 3.2v - 180ah battery

They show them in metal trays in banks of 8 cells. They could be assembled in blocks of 4 to get 12v. If my calculations are right each tray would be 360ah worth of batteries or two 180ah 12v blocks in a tray. Gerry said he saw 5 trays being lifted in place. That would equate to 1,800ah total. That would be 21,600 watt-hours? Hammill did say the number was rounded off. It seems plausible. The metal trays could be 8" x 24" each. The number of cells would be 40 total at a retail price of $226 equaling $9,040. This is just a guess from the video visual evidence and statements made.

But it is all "proprietary and sealed" so we may never know. But from this it appears plausible and could fit under the floor and weigh under 500 lbs. That is closely equivalent to about 800ah worth of AGM batteries in weight. So, it appears to be doable as stated by Roadtrek. Add solar contribution and maybe something like a 12v 85ah draw air conditioner and you can get your theoretical 24/7 air conditioning with full sun and a few hours of re-charge on the second alternator. My 160 mile per day driving history average would support it possibly without ever idling. The thing is, why? I don't use air conditioning hardly at all. Campskunk is running around claiming he doesn't either. I have had to reach to justify the 800ah I am installing in my B considering all plausible use scenarios. This leads me to believe this is all for demonstration of the possible but will it ever go into production?

[Belzar]

Just speculating on cost: standard CS etrek $150k + lithium/extra solar options/etc $15k + extended body $3k + 4WD $7k = $175 msp or about $150-$155 retail. A bit more if go for custom paint.

[obgraham]

I think the bigger feature than the batteries is moving the AC off the roof. Makes for a much less "industrial" looking van, maybe a little better mileage and gives RT a visual brand distinction

I'm not so sure that is an advance. You're changing from a widely used and easily repairable a/c system to a new and more proprietary one, the foibles of which are yet to be determined.

In my Class A DP, I had Winnebago's "basement air" system. The system was complex, difficult to work on, and incredibly loud right under your bed. I would have been happier with a couple of roof units. On the few occasions when I needed a/c I prefer to just have it blow that cold air right on me.

[gerrym51]

i think obgraham is correct.

[Davydd]

There is a stealth appeal taking the air conditioner off the roof but you see more and more Sprinter vans with air conditioning on the roof now. We will be so stealth with ours that we will look no different than an airport transporter or passenger van. They all have rooftop air conditioning lately. Not so a few years ago.

Other advantage besides more solar potential is lower overall height if you desire that. But with the van under 10 feet now and still over 9 feet there is not a lot of practical advantage. You still will not be able to pass through McDonald's standard 9 foot drive through canopy.

Is there an advantage with air distribution, comfort and noise? Those I cannot answer as I don't know enough.

The disadvantage of course is the precious real estate taken up. Up on the roof is no hit on that other than solar. Inside the van something has to give be it just raw storage space if nothing else. It could also constrict plan layout design. Underneath the floor it seems space is precious as well and something would also have to give.

[gerrym51]

the mdonalds near me is 9 feet 6 inches

[booster]

Originally Posted by gerrym51

the mdonalds near me is 9 feet 6 inches

So you are saying a roof air conditioner could be health benefit?

[Davydd]

Originally Posted by gerrym51

the mdonalds near me is 9 feet 6 inches

Then you'll just say goodbye to your Fantastic fan cover.

Corporate standard was 9 feet at one time. These are the kinds of things I paid attention to in my architectural career. I've done a lot of franchise architectural work in my career. I was even in charge of Target Store prototype design for several years. It's ingrained in me to check just about everything out in buildings. It is kind of a habit.

[gerrym51]

promaster is 8 feet 4 inches- with AC should be less than 9 feet 5 inches. the golden arches are golden to me

[Davydd]

Yeah, but Wendland has a Sprinter. We don't know if you'll change your mind yet. Haven't you been through about three model decisions this year already?

The air conditioners are anywhere from about 8" to 10" depending on models used. We stop for coffee a lot at McDonalds. It is generally more an excuse to get out stretch our legs and take a potty break. We don't drive on freeways all that much so don't get to many rest stops.

[gerrym51]

actually i have been-however i think it will be a zion. I had to wait to the first quarter of 2015-i promised the wife-who is not gung ho like me. the first quarter is almost here. However if they introduce 'another' new model i did not know was coming who knows. I will say that if i have not ordered a roadtrek by march 31 i deserve all the derision you put upon me. it just has not been totally in my control

[markopolo]

Florida RV SuperShow in January is big. It'll be nice to get reports from it. Maybe RT will have a production lithium battery RV there ? ? ? The Zion should be there. Maybe Jim will let everyone know what will be there.

[Davydd]

Here is another video on Wendlands new CS Adventurous.

http://roadtreking.com/roll-meet-new-ro ... turous-xl/

They showed a lowering storage shelf in the back end where they stored bedding. Also there is a vent in that cabinet. Could that be where the off the roof air conditioning was moved? There is a heater in the bathroom. The galley has a 2-burner propane cooktop so despite all the battery power the van is not all electric. Inside it appears to be a standard CS Adventurous with electric sofa. Nothing was said about their solar, lithium batteries or air conditioning innovations.

[bobojay]

Humm...no mention of the ultra mega smoke & mirrors battery system. WHY! would you have all that electric and the special diesel heating system and have the propane too? Does it not have the Webasto as their previous one did?
New powered step that'll be a maintenance nightmare I see. V6 or 4 I wonder.....