Good overview of lithium batteries and a solar/lithium upgrade on a larger RV

[sheral]

Originally Posted by Reed

Son is in solar (for 25 years) and is fabricating a solar system for the Roadtrek. Reed and Elaine

Very cool and so nice to know it will get done right. Can I ask, out of interest, what solar controller(s) has he chosen to work best with the lithiums? Pics when done please

[ClassB4Me]

Originally Posted by Davydd

Scale it down? ETreks and Advanced RVs have already exceeded what they put in.
The dual alternator is the best thing you can have in a B. AGM or li-ion it charges faster since shore power and Onan generators or single chassis alternators have much lower input. This should be a standard with Bs and eliminate the Onan. Quieter, less weight, space saving, fuel saving, more versatile, probably more fail safe and less maintenance.

The 2nd alternator used by Advanced RV looks quite large. Seems like it would be hard to find space for it. Would this only fit in a Sprinter-based RV?

https://youtu.be/XANYxoEF_HY

http://www.airforums.com/forums/f240...es-136063.html

Are there 3rd-party companies that specialize in RV-based 2nd alternator charging systems other than Roadtrek and ARV? Seems like a smart way to go if buying a new RV. Is there a clear downside as compared to a traditional generator?

FYI... I did read through prior thread conversations but wanted an update because technology is always changing and getting cheaper.

[avanti]

Originally Posted by ClassB4Me

The 2nd alternator used by Advanced RV looks quite large. Seems like it would be hard to find space for it. Would this only fit in a Sprinter-based RV?

Are there 3rd-party companies that specialize in RV-based 2nd alternator charging systems other than Roadtrek and ARV? Seems like a smart way to go if buying a new RV. Is there a clear downside as compared to a traditional generator?

Both ARV and RT source their 2nd alternators from Nation's Alternators (or at least the have done so in the past). They make bolt-on kits for many platforms:

Commercial Service Vans

We totally love ours. The only downside is the possibility of having to idle your engine, which some people think is not good for it. The upsides are to many to mention.

[ClassB4Me]

Originally Posted by avanti

The upsides are to many to mention.

• Weight Savings
• Less Maintenance
• Lower overall cost compared to a generator?
• Are they more efficient than using a generator?
• Seems like they can be quieter

- Do many people who go the 2nd generator route not do solar?

- So, if I don't need a generator, I guess I can buy a larger array of house batteries

- If I am traveling to my boon-docking site, I can turn on the 2nd alternator en-route and top off my array of house batteries quicker?

Sounds like this is the type of work best left to specialists. Thanks for the info.

[avanti]

Originally Posted by ClassB4Me

• Weight Savings
• Less Maintenance
• Lower overall cost compared to a generator?
• Are they more efficient than using a generator?
• Seems like they can be quieter

- Do many people who go the 2nd generator route not do solar?

IMO, you still want modest solar. Not to supplement the alternator (it is a drop in the bucket), but to keep your battery fully-charged and healthy when parked. This is less compelling if you park indoors.

- So, if I don't need a generator, I guess I can buy a larger array of house batteries

Sure. You will have freed up a lot of space and weight.

- If I am traveling to my boon-docking site, I can turn on the 2nd alternator en-route and top off my array of house batteries quicker?

Mine doesn't even have a switch. The Balmar regulator that Nation's sells is a fully-programmable 3-stage charger. It takes care of itself. My 440Ah battery will fully charge in about one hour's driving. I rarely think about it.

Sounds like this is the type of work best left to specialists.

I did a self-install, with a little help from my local mechanic. Not rocket science but it is not a beginner's project.

[pattonsr]

I believe the Sprinter Store in Tualatin, OR sells and installs the Nations alternator kit.

[gregmchugh]

The new alternator ARV is using is clearly a major upgrade and best of all, one of our favorite ARV owners can continue to justifiably claim "Mine is better than yours..."

[avanti]

Originally Posted by gregmchugh

The new alternator ARV is using is clearly a major upgrade

Clearly.

But, I would sure like to hear a little more about exactly what problem(s) they are addressing that motivate a nearly 3X increase in cost.

[gregmchugh]

Originally Posted by avanti

Clearly.

But, I would sure like to hear a little more about exactly what problem(s) they are addressing that motivate a nearly 3X increase in cost.

I don't think ARV ever got the Nations alternator cooled to the level that they wanted but someone may be able to confirm that cooling was one of the issues resolved by the new alternator.

[avanti]

Originally Posted by gregmchugh

I don't think ARV ever got the Nations alternator cooled to the level that they wanted but someone may be able to confirm that cooling was one of the issues resolved by the new alternator.

Well, as Pattonsr pointed out in the other thread, the Balmar regulator is capable of monitoring the alternator temperature and modulating the load accordingly. This would seem to be a complete solution to any overheating issues. Of course, this does reduce output slightly, so if their motivation was greater output, I guess it makes sense. But I haven't heard anybody with a Nation's alternator complaining about lack of amps. It certainly provides more than enough for us.

[avanti]

The ARV alternator video got me wondering how my stock Nation's Alternator pulley is behaving, so I made a video:

https://www.flickr.com/photos/412063.../in/datetaken/

Comparing this with the ARV video:

https://www.youtube.com/watch?v=XANY...ature=youtu.be

is interesting. I took shots at idle, with the alternator both unloaded and at load. Unloaded, there is almost no sign of the oscillation seen in the corresponding ARV clip. At load, there is minor oscillation, but nowhere near the violent motion that the old ARV setup exhibits.

It should be noted that the old ARV belt-and-pulley setup does NOT appear to be the standard Nations setup (or at least it is different from mine). I have been assuming that they were using the entire kit that Nation's sells, but this does not appear to be the case.

My conclusion is that their new pulley system is indeed much better than their old one, but it does NOT appear to be dramatically better than the system provided by Nation's. This does not surprise me, since the Nation's hardware has always impressed me as being of very high quality. The problem that their new setup is addressing appears to have been self-inflicted.

As an aside, I am somewhat skeptical that the differences in audio on the before/after ARV video clips accurately reflects the noise levels of the respective setups. Most of the noise is almost certainly coming from the engine, not the alternator. I am not suggesting that they were being intentionally deceptive--I'm sure it was just differences in camera-mic positioning. But it does misleadingly add to the "gee whiz" vibe of the comparison.

[pattonsr]

avanti,

You have an I4 engine. Is the Nations pulley system different for the 6 cylinder? I thought at one time it was but I am not sure.

Thanks for doing the video. I find the sound level just fine which is what I expected.

[avanti]

Originally Posted by pattonsr

avanti,

You have an I4 engine. Is the Nations pulley system different for the 6 cylinder? I thought at one time it was but I am not sure.

That is a good point. I have never seen an install on a V6, and it is a different SKU. Here is a picture from the Nations website:



This is completely different from the I4 kit--looks a lot more complex. It is hard to tell for sure, but this doesn't look like the setup in the ARV video, either. I definitely could be wrong, though.

[Boxster1971]

Also if you look closer at the ARV videos you will see that all shots are of the monster Delco alternator with different pulley installations. There is no shot of the Nations alternator in the ARV video.

My guess is they installed that Delco; found a problem and had to develop a special pulley.

Edit: Actually they didn't development it - it already exists. Here is link to pulley that ARV is using.
http://www.decouplerpulley.com

[gregmchugh]

My take on the ARV upgrade is that they are always looking for ways to improve the quality, reliability, and performance of all the systems in the van. I don't get the impression that there were major issues with the prior alternator system that forced them to switch but they had seen failures and they saw that the performance was degraded due to heat and they observed the fact that belt life was going to be reduced with the load oscillations in the old setup. The issues they saw were not show stoppers and the overall performance and reliability of the old system were likely reasonable at the price point of the system.

But it is also clear that you can spend more money and get a better system with the only penalty being the added weight of the higher performance system. Since cost is likely not a major factor in the ARV trade off analysis when designing a van and quality/customer satisfaction/performance/reliability are major factors they simply decided to implement a design improvement that aligns with their goals.

Is this type of change something that would make sense for the mainline Class B manufacturers?

Probably not, the benefit vs cost trade off would not play out the same way...

The readily available Nations high performance aux alternators are not bad choices but as you might expect there are even better performing options at higher cost and not readily available as a easy to obtain package of components...

[ClassB4Me]

Originally Posted by gregmchugh

My take on the ARV upgrade is that they are always looking for ways to improve the quality, reliability, and performance of all the systems in the van. I don't get the impression that there were major issues with the prior alternator system that forced them to switch but they had seen failures and they saw that the performance was degraded due to heat and they observed the fact that belt life was going to be reduced with the load oscillations in the old setup. The issues they saw were not show stoppers and the overall performance and reliability of the old system were likely reasonable at the price point of the system.

But it is also clear that you can spend more money and get a better system with the only penalty being the added weight of the higher performance system. Since cost is likely not a major factor in the ARV trade off analysis when designing a van and quality/customer satisfaction/performance/reliability are major factors they simply decided to implement a design improvement that aligns with their goals.

Is this type of change something that would make sense for the mainline Class B manufacturers?

Probably not, the benefit vs cost trade off would not play out the same way...

The readily available Nations high performance aux alternators are not bad choices but as you might expect there are even better performing options at higher cost and not readily available as a easy to obtain package of components...

There is a ton of brain power in this forum with zero marketing spin.

So, to summarize....

In a Class B van with two or more house batteries, and more drive time than 'parked at resort time' (2 days consecutively max.), a secondary alternator is the better approach (from a cost / benefit perspective) than attempting to add more solar arrays?

The one primary benefit to the secondary alternator (I can see) is the ability to run the coach A/C while traveling down the highway.

This has helped when you have to make a choice where to allocate $3000 (Solar, Generator, Alternator) + batteries

[gregmchugh]

Did not realize I was covering marketing, I thought I was on another topic...

The underhood generator is usually marketed as an alternative to an Onan generator and I don't see any reason to get an Onan when an underhood generator is an option. Some people will disagree with that I expect. On a diesel van the propane Onan has the negative of not using the same fuel as the van engine and propane is not very efficient for powering a generator vs gasoline or diesel. If you want to run your roof air conditioning while driving or while boondocking some type of generator is needed either the Onan or an underhood generator.

Solar vs generators of any kind is another discussion. If you can keep your daily boondocking energy needs within the solar charge capability that fits on your van then a generator could be there simply as a backup for low solar days. If you have AGM batteries the solar is a good supplement to the generator for the absorption charge phase. If you have a large battery bank and use a lot of power then solar is not going to cut it by itself on a Class B size roof unless you have a XL Sprinter with no roof air conditioner and pack it full of panels like the Campskunkmobile. 600 watts of solar is possible on a Class B roof with an air conditioner which gives you about 150-210 amp hours per day of battery charge but most people have less than 600 watts. If you have a big honking lithium battery bank and use it for air conditioning you really have no choice but to use an underhood generator when boondocking.

Deciding on the right balance between battery bank capacity and battery type and generator and solar seems to be something that is always oversimplified in the marketing and sales side of the RV business. More is always better from a marketing perspective...

That is as close as I get to a marketing discussion...

[pattonsr]

gregmchugh,

"If you have a big honking lithium battery bank and use it for air conditioning you really have no choice but to use an underhood generator when boondocking."

If boondocking in one location for several days that requires air conditioning in order to survive, I plan to use a Yamaha 2400ishc or EF2000isv2 that is converted to use propane from the onboard Unity propane tank to run the air conditioning as much as I need to which avoids idling the engine. Using a Magnum MSH3012M inverter/charger, when the air conditioner compressor is on, then the Yamaha provides the power. The hybrid Magnum will supplement with battery power if more is needed. When the compressor is not running, then the Yamaha will charge the batteries.

If one is staying only one day or one takes day trips with the Sprinter, then a large Lithium bank will stay full using the second alternator.

While driving the second alternator will provide enough power to run the roof air conditioner so dogs or people in the rear will be happy.

Davydd need not reply since he will never find himself needing air conditioning.

[gregmchugh]

pattonsr,

I guess I don't see a big advantage to carrying a propane portable generator when you have an underhood generator except to avoid engine idling which I personally don't have any problem with. Not sure how much propane a converted Honda/Yamaha uses but the propane Onan in our Roadtrek RS uses about 2 lb per hour at 2000 watts so the typical 40-50 lb propane tank needs refilling pretty often when you use it a lot at high power for AC or battery charging.

I am in the group that rarely uses air conditioning but if I was planning to use air conditioning a lot when not plugged in, I would prefer one of the high efficiency 12v DC air conditioners rather than the regular 120v air conditioners.

[pattonsr]

gregmchugh,

A Yamaha ef2000isv2 sips propane compared with an Onan 3600. Plus it is very quiet compared with the roar of the Onan.

I am not familiar with 12v air conditioners. Are there any 15000 btu models?

Florida or Texas in the summer requires a 15K which for a Unity would be a ducted model. Dometic has announced the new Blizzard NXT which seems to be the latest and greatest in 120v models.