Walk thru Video on the new Lithium TRAVATO

[avanti]

I wonder what this "8 year" warranty says about battery capacity loss. Capacity will deteriorate over time. When, if ever, would they replace the batteries due to such deterioration?

[BBQ]

Something to learn from the ARV

They have already done the research two years ago

https://www.youtube.com/watch?v=XANYxoEF_HY

[GeorgeRa]

Originally Posted by avanti

We all should hold our judgement, but I am pretty optimistic about fuel cells. I have no data, but I suspect that a LOT more R&D is going into them than quiet dyno-fuelled generators. ICE is a dead end and everybody knows it. I agree with you that gensets could be vastly better, but nobody is going to bother.

OTOH, fuel cells combined with a medium-sized AGM battery are a potential game changer. As I said above, I think that such a setup could ultimately be just as good as a huge lithium system, without the onerous management issues. Whether it will have its own downsides remains to be seen.

The key reason for my skepticism is fuel requirement, hydrogen is necessary for efficient fuel cells. It can be distributed via Schwarzenegger’s Hydrogen I-5 freeway or made in situ from a methanol or an LPG fuel or other hydrogen loaded chemicals. This in situ generation of hydrogen is a major challenge, it requires high temperature catalytic reaction very sensitive to contamination, high purity fuel would be difficult to get from LPG RV distribution. So a special LPG or other fuel would have to be distributed at likely high cost. I wish to be more optimistic but I am not.

[cruising7388]

Originally Posted by avanti

I wonder what this "8 year" warranty says about battery capacity loss. Capacity will deteriorate over time. When, if ever, would they replace the batteries due to such deterioration?

That's a good ask - whether significant battery degradation short of failure is excluded from the warranty. The Volta batteries use the same chemistry that is used in automotive EVs and hybrids and in the automotive application, the OEM is required to provide an 8 year warranty and in Carb states I think it's a ten year period.

In autos, it appears that these batteries survive this lengthy warranty period because they are computer controlled to limit the depth of discharge and recharge to levels that promote an extended life. My guess is that in the RV application, typical discharge and recharge levels will be considerably greater than that which would invite battery degradation but that perhaps this could be largely offset by a lower incident of these cycles in an RV compared to a typical EV or hybrid.

Roadtrek's lithium battery warranty contains no specific language excepting degradation but IIRC, there has been some incident where Roadtrek and a customer were at loggerheads over just this subject. The owner demonstrated loss of battery capacity but Roadtrek countered that this degradation was normal, I don't know how this was eventually resolved.

[avanti]

The Chevy Bolt guarantees 60% capacity over the 8 year warranty.

https://electrek.co/2016/12/07/gm-ch...o-40-warranty/

[avanti]

Originally Posted by GeorgeRa

The key reason for my skepticism is fuel requirement, hydrogen is necessary for efficient fuel cells. It can be distributed via Schwarzenegger’s Hydrogen I-5 freeway or made in situ from a methanol or an LPG fuel or other hydrogen loaded chemicals. This in situ generation of hydrogen is a major challenge, it requires high temperature catalytic reaction very sensitive to contamination, high purity fuel would be difficult to get from LPG RV distribution. So a special LPG or other fuel would have to be distributed at likely high cost. I wish to be more optimistic but I am not.

Well the WATT people seem to think they can do it. Their website says:

WATT Fuel Cell Corporation is a developer and manufacturer of Solid Oxide Fuel Cell (“SOFC”) stacks and systems that operate on common, readily available hydrocarbon fuels such as propane, natural gas, JP-8, and diesel.

I don't really know enough to be optimistic or pessimistic, but I am hopeful. I find the RV fuel cell scenario to be pretty compelling. But wishes don't catch fishes...

[Davydd]

Originally Posted by BBQ

Something to learn from the ARV

They have already done the research two years ago

Neither of those two alternators are in the Volta system. I've had both installed in my ARV and can tell you the Delco is vastly superior to the Nations. The Volta alternator to my understanding is smaller than the Nations and of course the major benefit is twice the current of my Delco, maybe more than the Nations though no one has advertised it as such and, of course, smaller wiring that saves weight. I probably have at least 20 ft. of 4/0 wiring and that is heavy.

I understand, though I haven't investigated yet with ARV, that they are providing a second 12v alternative. Clients can have LiFeMgPO4 batteries from Valence Technology installed. Unlike the standard LiFePO4 batteries, the Valence batteries can be safely stored down to -40 C. -40 C is also -40 F, which is the same as AGM battery limits in cold storage.

Of course charging should not take place with lithium ion below freezing temperatures. Mine is conservatively maintained at 41 degrees F. at all times. That Travato depends on a conditioned space interior at all times. I'm not sure that is practical or energy efficient. I still contend the easiest method of keeping lithium ion batteries above freezing is from the batteries themselves short term with 12v resistant heating pads local to an insulated battery box (and I have done it for a week 24/7 below freezing weather) and longer term storage with nothing more than 15amp shore power. By code every home has an outside 15amp outlet. So you don't need a special 30amp RV outlet.

What real life experience says is lithium ion batteries in use are anywhere from 10 to 20 degrees above ambient temperatures. My heating pads typically don't come on until ambient gets down to the low 20 F. and then they operate intermittently. So in the worst case with 10A of heating pads the the battery draw would probably be less than 200ah in a 24 hour period and I would guess few would camp down to 20 F. anyway. And, if so, driving less than an hour would restore the battery. With my 800ah battery bank it is insignificant.

Edit: It has worked for me over three winters now.

[cruising7388]

Originally Posted by avanti

The Chevy Bolt guarantees 60% capacity over the 8 year warranty.

https://electrek.co/2016/12/07/gm-ch...o-40-warranty/

Because of the difference in use patterns among the owners, I can't see how degradation can be uniformly quantified. The Bolt has a maximum driving range of 240 miles. Wouldn't an owner that never drives more than 50 miles between recharges enjoy a significantly better degradation profile than an owner that drives 200 miles between recharges?

Faced with a 40% drop off, I think I'd skip the Bolt and go for the series hybrid Volt.

[avanti]

Originally Posted by cruising7388

Because of the difference in use patterns among the owners, I can't see how degradation can be uniformly quantified.

I think what they mean is that they are guaranteeing that your range won't degrade more than 40% over the lifetime of the warranty.

[gregmchugh]

Originally Posted by BBQ

Something to learn from the ARV

They have already done the research two years ago

Going to a 48v battery bank allows a smaller, lighter, higher power alternator for charging. Here is the spec for the Volta alternator. Specs for the rest of the system components are also on their website at the second link.

https://voltapowersystems.com/wp-con...et_9.15.17.pdf

https://voltapowersystems.com/energy-storage/

[avanti]

Originally Posted by gregmchugh

Going to a 48v battery bank allows a smaller, lighter, higher power alternator for charging. Here is the spec for the Volta alternator. Specs for the rest of the system components are also on their website at the second link.

There are certainly a lot of advantages to higher voltages, but there are negatives as well. 48VDC cars have been "just around the corner" for 15 years now, due to a number of technical challenges. One of the big issues is the severe arcing (and consequent short component life) that occurs across dry contacts (such as switches and relays) with high voltage DC. This is not an easy problem to solve with mechanical switches. This is apparently one of the things that has slowed progress in 48V vehicle design. I imagine that solid state relays have made this less of an issue. I just hope that the RV world is aware of such long-term issues. It is one thing to make it work. It is another to keep it working. Yet another reason to go with real engineers.

[BBQ]

.

Now all they need is a tensioner that won't shred the belt.



.

[cruising7388]

Originally Posted by gregmchugh

Going to a 48v battery bank allows a smaller, lighter, higher power alternator for charging. Here is the spec for the Volta alternator. Specs for the rest of the system components are also on their website at the second link.

Looking at the alternator specs, it doesn't cut in until the alternator shaft speed is above 2732 rpm. With a 2:1 pulley ratio that would require an engine speed of 1366 rpm. With a 3:1 ratio it would be 910 rpm. Aren't either of these engine speeds higher than conventional idling produces?

[Davydd]

Originally Posted by cruising7388

Looking at the alternator specs, it doesn't cut in until the alternator shaft speed is above 2732 rpm. With a 2:1 pulley ratio that would require an engine speed of 1366 rpm. With a 3:1 ratio it would be 910 rpm. Aren't either of these engine speeds higher than conventional idling produces?

MB fixed high idle option is about 1200 rpms. That's the option ARV used for mine. The variable option can be higher. For the life of me, why does everyone think about just idling? I don't have to idle my ARV. Just drive it. I seldom ever idle our ARV to charge batteries.

[cruising7388]

Originally Posted by Davydd

MB fixed high idle option is about 1200 rpms. That's the option ARV used for mine. The variable option can be higher. For the life of me, why does everyone think about just idling? I don't have to idle my ARV. Just drive it. I seldom ever idle our ARV to charge batteries.

You seldom idle for charging because you have the luxury of 800ah.

[Davydd]

Originally Posted by cruising7388

You seldom idle for charging because you have the luxury of 800ah.

You sink money into a lithium ion battery system, second alternator and inverter you are not doing yourself a favor to not go big where no AGM system can go for weight and space restrictions.

Does the Travato Volta system have an auto start and high idle feature for idling?

[BBQ]

Originally Posted by Davydd

...

Does the Travato Volta system have an auto start and high idle feature for idling?

According to The FitRV... yes to both.

The auto start is based on DOC, not voltage as in RT's system.

[gerrym51]

I think the biggest thing here is this. Most of us agree that ARV tries to do the BEST in improving. They charge for it but they do it.

If at this point they think the Volta system is the best and are installing it on their vans why should we question it.

Will something come along that will be better eventualy-i'm sure it will.

However if Travato uses the same system-but smaller battery-obviously because of space- why wouldn't one have as much confidence as can be inferred.

[BBQ]

Originally Posted by gerrym51

I think the biggest thing here is this. Most of us agree that ARV tries to do the BEST in improving. They charge for it but they do it.

If at this point they think the Volta system is the best and are installing it on their vans why should we question it.

....

They have also chosen recycled denim as insulation.


They are an experimental shop.
Everyone one of their RV is different.
Not saying it is bad,
just saying that blind faith is not recommended.

[booster]

Has anyone seen how the Volta alternator is mounted on the various engines yet?

At some point, you have to start getting concerned about pulling horsepower off a cantilevered pulley in the front of the engine, due to load on the front main bearing of the engine. The Volta will basically double the sideload, so that starts to get to be a quite a lot of power being pulled off, especially with AC, power steering, etc.

I think the Nations setup on Sprinters put another pulley outboard of the stock belt setup, so more lever arm there, except maybe on Roadtreks. On the Chevy system, they used the stock belt system with a longer belt