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About the Amazing Lithium-ion Battery System in Our New RV

Tomorrow, Jennifer and I head to American RV in Grand Rapids, Mich. to pick up our brand new Roadtrek CS Adventurous XL.

You’ll soon see videos and photos of it and there will be lots of blog posts as we head out across North America in our new motorhome.

But before that,  I need to address the issue of lithium-ion batteries on our new CS Adventurous XL.

Yes, we have them.

A lot of them.

But other than that, there’s not much more I can discuss publicly.

That’s because the system I will be using, like the earlier one being tested by Roadtreking Reporter RT Campskunk, is still, officially, under development by Roadtrek Motorhomes. Campskunk has been testing his system since early fall. Campskunk and some other testing has proven the concept is not only viable, but groundbreaking. Campskunk has a strong mechanical bent. He could design and probably build a motorhome singlehandedly. His use of the lithium-ion system has been invaluable in helping Roadtrek engineers fine tune their innovation.

The system Roadtrek has allowed me to use in the new CS Adventurous XL we’ll be driving is the next evolutionary step. The fact that I am part of the test shows how far along it is. I’m the everyman, the typical RVer who doesn’t profess to understand how it works, who just uses it. In other words, the fact that I am part of the test shows how close lithium-ion power will be for all of Roadtrek’s customers.

Because lithium-ion power these days is perhaps the most fiercely sought after innovation among RV manufacturers – they are all scrambling to come up with a system – you can understand that Roadtrek, which is eons ahead of the competition, is going to carefully protect the system it has developed. The system I have is sealed and proprietary.

So what can I say?

I can say that I have 20,000 watts of available power. That is not a typo. 20K.

Let me put that in perspective: I just had a whole house automatic generator installed at my sticks and bricks house. I wanted it to handle everything: Lights, heat, appliances, air conditioning, the well, my computer system, my recording studio. The contractor installed a 20K genertator. He said it was probably more than I needed.

The system in our CS Adventurous XL is 20K.

That means I can boondock and use AC for amazingly long term off-the-grid camping.

As far as price goes, you know the saying, “if you have to ask, you can’t afford it.” Lithium-ion batteries are really expensive. As it currently stands, the system I am evaluating would be many thousands of dollars above the cost of the motorhome. Roadtrek President Jim Hammill says the company is working on bringing the price into an affordable sphere and that will take some volume and negotiation. But make no mistake: Lithium-ion is a costly option.

What’s the big deal about lithium-ion batteries? Compared with the lead acid batteries found in most RVs, they have an amazingly long cycle life. Some studies suggest they can handle up to 5,000 cycle uses. Lead acid batteries are typically good for 500 to 1,000 cycles. They also charge very fast, up to 100 percent of capacity. Lead acid batteries charge to about 80 percent and then need much more time to get to not much more than 85 percent. Lithium-ion batteries are smaller and weigh about one-third less than lead acid batteries.

One concern some have when they hear talk about lithium-ion batteries is the danger of fire. Lithium-ion batteries have been around since the 80’s. We’ve seen them used in small devices like computers and electric tools for years. Remember a dozen or so years ago the stories about lithium-ion batteries in laptops suddenly bursting into flames when overcharged? Then there have been some stories about similar issues in the airplane industry.  Those issues led to a change in the formula that is used to make large lithium-ion batteries and now they are so safe that many other industries besides the RV industry are about to introduce them to their customers.

Roadtrek is all over this and the unit Jennifer and I will be driving around North America will one day be followed many others who will be able to choose lithium-ion power as an option.

The roof is covered with solar panels
The roof is covered with solar panels – 650 watts worth

Lithium-ion will probably always be an expensive, thus not for everyone.  But as you have just learned, this technology is highly advantageous for RVers like us who like to camp off the grid for extended periods of time.

Supplementing the lithium-ion coach batteries in our new CS Adventurous XL is solar power – 650 watts worth. The entire roof of our coach is covered with solar panels.

And our unit also has the proprietary Roadrek engine generator, which, when the batteries do eventually wear down after long periods of boondocking, can be used to charge it all up again. Really, though, with 20,000 watts of power from the lithium-ion system, I can’t imagine us having to do that very often.

So – for now – this is my definitive piece on the lithium-ion battery system we have. I needed to explain it to you but not reveal anything that would allow Roadtrek’s competitors from trying to rip off their technology. For most of my readers, I’m sure this will be enough. A small number of armchair engineers, however, will demand more details. I will not be providing more details until Roadtrek itself releases them.

I’m incredibly blessed to be able to be part of the test of this system which, as I said, someday soon, will be an option available to everyone.

So as you see the photos and read the blog posts about us boondocking and camping off-the-grid, you’ll be able to read between the lines and know that one of the reasons we can stay out there so long is because of that amazing lithium-ion power system.

 

 

 

7 thoughts on “About the Amazing Lithium-ion Battery System in Our New RV”

  1. yes, they are expensive, but waiting until they aren’t to do the R&D necessary to have a functioning system that works with the rest of the etreknology means losing precious time. these batteries are coming down like solar panels, and will soon be affordable – and actually preferable – to lead-acid batteries. i fulltimed for four years in my Chevy with lead-acid batteries, and always had to replace them every year because i would cycle them twice or more often per day. after a few hundred cycles, a lead-acid battery just won’t hold a charge anymore. i bought expensive lead-acid batteries. they lasted 15 months instead of 12 with my fulltiming usage pattern. four sets of batteries is about $2000. it adds up.

    1. Our son designed and fabricated our current system two years ago on our 34′ Open Range 337RLS (inexpensive but nice). It has 1.4 kW of panels (two sets of 3 x 235 W panels in for 90 V per series and then combined (parallel) to controller at 90V). Controller is a TriStar MPPT-45. Battery suite is 8.6 kW-hr (48 V nominal = 9.6 kW-hr at 54 V float). Suite is 4 x Manzanita Micro Batteries (EV battery fabricator) in series. Each Battery is 4 x 3.4 V (nominal) Chinese Aviation Lithium Battery (CALB) cells. Power goes to rig via Magnum 4.0 PSWI and 508 W Mean Well 48 to 12 V converter.

      John Arnold –
      We have harvested up to 8400 W-hrs on sunny days in June. We have gotten less than 300 W-hrs when “camped” in the Olympic Peninsula rain forest. We lasted 6 days there and were down to about 40% SOC. We still used the micro-wave and watched BBC Mystery Theater DVD at night. If there is good insolation, we can use the Dometic power hog a/c (1750 W draw) for 3.5 hours as combination of solar/battery suite. Our general MO is to be hiking/reading in shade during the day and then utilize the a/c for half an hour to an hour at dusk (900 to 1800 W-hrs) to cool the rig and then use 12 V fans for cooling. We have tied into line power once in two years and that was in a trailer park in Spokane when it was 103 and we were in the shade.

      We basically run the Dometic fridge (another power hog) on AC during the day. If there will good insolation on the following day, then we leave it on AC at night and face a -3000 W-hr deficit at dawn. We also run the hot water on AC when we have good insolation..

      Weight comparison with lead acid is three or four. Our battery suite is 250# and we would require 750# to 1000# to obtain the same energy reserve. Such an increase would be more than the rating for the king pin and rear axle of the pickup (8500#). As it is, we are 1000# under trailer axle rating, 3000# under trailer tire rating (Michelin), 750# under dualie rear axle rating (80 gallons of diesel, 40 gallons of fresh water etc in pickup), 4000# under rear axle tire rating (Michelin) and right on the pickup forward axle rating/2000# under front tire rating.

      We pretty much boondock/mootchdock (set up in the backyards of our kids for two or three weeks) on BLM/Forest Service dispersed sites: quietude and lots of wildlife. One photo is on the beach in Yucatan (with older rig destroyed in 70 car pileup between Orizaba and Puebla). The other was taken by son Charlie at Conchas Lake.

      Reed and Elaine

  2. 20kW of power is impressive, but it says nothing about the capacity. In other words, it looks like the battery could power your home, but you don’t know *for how long*, it could well be that drawing 20kW will deplete the battery in ten minutes.

    The spec to look for is watthours, or kWh, like on your utility bill. Any idea how many kWh this new battery can hold?

  3. I will try to guesstimate the parameters. I am assuming that 20kW means 16 batteries, 6V, 200 AmpHours. (1200 Watt Hours) each. These Would cost roughly $1200 each compared to the normal AGM battery costing roughly $200. And the weight would be 30 lb. each vs 60 lb. for the AGM battery.
    Clearly, thats a lot of battery, and should power the complete RV for 2 Days, or more, depending on how much Air conditioning is used. But at present prices it is quite expensive; but prices are expected to drop roughly 15% per year.
    I am at the other end of the spectrum, would be happy for 24 hours on a battery charge, but would like the microwave and limited Air Conditioning. Can this be done with 2 lithium batteries? In theory, a lithium battery should be at least twice as useful as a AGM battery, as they are easier to charge to full capacity, and unlike the AGM, which is considered discharged at 50% of capacity, the Lithium Battery can be discharged to 15% or less of capacity before the voltage falls off.
    Does Campskunk or anyone else have real world apples to apples experience on how long an RV with Lithium Ion will run vs comparable AGM batteries.

  4. Great innovation. Though my first sense is these efforts ought to be coordinated with the EV industries efforts especially Tesla, GM, Chrysler and others. They are driving the cost of batteries much, much lower – especially Tesla.

  5. While I appreciate that for the RV *manufacturer* using lithium ion batteries for coach power is definitely a welcome development, I believe in giving proper credit where it is actually due – to some of the pioneers who actually created their own battery banks by connecting many smaller batteries together, putting together their own control and monitoring apparatus and solar generation and using the system every day. This person in particular set up his own system 4 years ago http://www.technomadia.com/lithium/ and I am hoping that the RV manufacturers are paying attention to his findings since then: http://www.technomadia.com/2015/02/living-the-lithium-lifestyle-3-5-year-lithium-rv-battery-update/ As far as I can tell it’s the work of dedicated individuals “pushing the envelope” that eventually results in innovation on the part of RV manufacturers. From what I can see most of them are pretty far behind any technological development curve you might choose to look at. Generally speaking they are not a hotbed of research and development – nor should they be as I doubt their business model could support that.

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