Lithium Ion Battery

wincrasher · 10-26-2014, 05:04 PM

What do you guys think of this battery?

http://www.lithiumion-batteries.com/...m-ion-battery/

Basically they are claiming you can draw it down 100% each time. After 2000 cycles, you'd have 20% degradation - so it would be an 80ah battery after that.

I do like the drop in aspect of it - so you don't need to change your charger or converter from what you already have. Also only 28 lbs!

Pricey at $1300, but with 3x the cycles, it may be worth it.

With that capacity, instead of rigging up a frame to hold a second AGM, one of these smart batteries may be like having two of the AGM's.

gerrym51 · 10-26-2014, 06:50 PM

Wincrasher-more knowledgable than me have commented on lithium before. It's not just the batteries but also heated compartments to keep above freezing so they can always be re-charged and useful. I believe Davydd and Advanced Rv uses and will use these.

mikes47 · 10-26-2014, 07:00 PM

Be aware that you need to plan for charging when temp drops below freezing. Perhaps install in a heated, sealed enclosure like the folks @ Advanced RV are doing. The batteries work fine to provide power at those freezing temps, but they don't like taking a charge under those conditions.

Davydd · 10-26-2014, 09:04 PM

There have been some Advanced RVs that had those batteries installed with a lot of energy management behind them, but they are no longer offering them. This is their strategy now:

Go Farther Off the Grid:Advanced RV Redesigns Battery System

The don't use those Smart Batteries as they now use LiFePO4 built up from single cells into 400, 600 or 800 ah assemblies. The batteries would be more like this:

Elite Power Systems GBS Batteries

We are getting the 600 ah assembly installed. The battery management is very sophisticated. For one it is governed so the draw down doesn't go below 20%. There is an autostart charging system. Each battery cell is monitored for both voltage and temperature. The charge patterns are different than lead-acid batteries so I doubt it is as easy to just drop a substitute battery in for a lead-acid battery. A lot of this was already covered in my Advancing Alvar thread.

wincrasher · 10-27-2014, 12:51 AM

Thanks Gerry, didn't realize the issue with freezing. For those of us not interested in $200k vans, I thought these Smart Batteries might be a good upgrade option to get little more capacity. Not very practical in my case unless I found a place inside my van to install one or two of these.

Davydd · 10-27-2014, 01:46 AM

Wincrasher,

You dare not over charge a lithium ion battery either. Lead-acid wet cell you just boil out water you can replace if you over charge. Lithium ion will distort permanently. I'm not sure what kind of charging system is in your Travato but I do know the 2013 Winnebago ERA did not have intelligent 3-stage charging so would have had a good chance of destroying a lithium ion battery. As I mentioned too, the charging is not the same so even if you had the 3-stage intelligent charging I don't know if it would work or be enough to manage lithium ion batteries.

If your batteries were placed inside your van and you decided to personally stay warm, the freezing issue should not be a problem. They still function if they have charge in them and I think better than lead-acid. You cannot bulk charge if the cells are below freezing. Think about it. The same problem exists with your laptop computer, tablet and cell phone in your van.

As far as space goes, those Smart Batteries you referenced are designed to be similar size to lead-acid or discreet car batteries as they are called for direct replacement as you surmised. That size is probably artificial. The single cell modules put together to create a 12V battery are not only lighter but smaller.

I might be early with adopting lithium ion battery systems but I am enjoying the challenge of it. I suspect in a few years it will be the standard in Class Bs especially if the prices continue to drop and Roadtrek has their way and are successful with their Etrek boondocking movement forcing the other converters to wake up and think about challenging and competing. Maybe when Roadtrek decides to get back in the lithium ion game it will then be standard that can't be ignored. Advanced RV is all in on it.

wincrasher · 10-27-2014, 02:46 PM

I got a nice message this AM from the Smart Battery people. They say their batteries are good down to -20c. If you are going beyond that, they provide 12v heating pads for the batteries. Depending on draw, I'm not sure how nutty an idea that is.

As there materials show, charging is controlled internally by the circuitry inside the battery. That makes me wonder how any external battery charger would really work with it. Winnebago started using the PD charger/controllers a while ago which purport to do 3 stage, but I certain there are better out there, but what good is it if the battery controls it anyways.

Sent from my iPhone using Tapatalk

Davydd · 10-27-2014, 03:48 PM

Here are a couple of websites that have installed LiFePO4 battery banks in RVs and Sailboats that seem similar to what Advanced RV is doing. There is a couple of years success behind them. They might give more insight as both websites go into great detail about the pros and cons of all the battery systems.

Mar Azul Sailboat on Lithium Ion Batteries

Technomadia on Lithium Ion Batteries

Then there is a wealth of info from Battery University. This is where I confirmed about charging under freezing temps.

BTW, the lithium ion batteries presumably function well down to -20C. They just can't be recharged below 0C or 32F without suffering some permanent damage. The heating pad has to be capable of maintaining the the battery cells above freezing so you can recharge them. I still have questions about this. Where do you get the energy for a heating pad? Obviously the alternator while driving and shore power when parked. But boondocked?

Davydd · 10-27-2014, 04:33 PM

Quote:

Originally Posted by wincrasher

I got a nice message this AM from the Smart Battery people. They say their batteries are good down to -20c. If you are going beyond that, they provide 12v heating pads for the batteries. Depending on draw, I'm not sure how nutty an idea that is.

As there materials show, charging is controlled internally by the circuitry inside the battery. That makes me wonder how any external battery charger would really work with it. Winnebago started using the PD charger/controllers a while ago which purport to do 3 stage, but I certain there are better out there, but what good is it if the battery controls it anyways.

Smart Battery is claiming a built-in each battery a battery management system. When the cells drop to 8 volts they just shut down. No more power for you. Same at the other end. When fully charged they cut off further charging. I think your cell phone batteries behave similarly. So if they are governed at 8 volts that means they don't 100% discharge nor do they probably 100% charge as I would guess there would be a protection cushion at both ends. They want to keep their batteries viable for thousands of cycles. So, in theory you would not need intelligent charging. You don't need 3-stage at any rate because lithium ion batteries would not go through an absorption phase as lead-acid does nor float since you bulk charge until topped off.

The 100% discharge is a theoretical number. All batteries can be discharged 100% but doing so greatly diminishes life cycles. Sometimes very rapidly. Some claim you can discharge AGM batteries 80% but if you read that Mar Azul Sailboat web page it would also mean frequent replacement of batteries. 50% discharge is the practical limit for AGMs. Advanced RV told me they think lithium ion batteries could be discharged down to 10% with no problems but they are building a battery management system to shut down at 80% discharge for safety leeway. So their tests say their batteries will last 5,000 cycles with that leeway. I noticed Smart Battery has increased their cycle claims as well. Criminy, even if you full timed and charged every day (which you wouldn't) 2,000 cycles would get you 5.5 years. I suspect if battery management works as claimed, once installed is the last worry. So the batteries could be placed anywhere. They don't outgas. You don't have to maintain connections because of corrosion, and you don't have to keep water in them as you would a wet-cell.

wincrasher · 10-27-2014, 06:20 PM

I think you have to take that 100% discharge with a grain of salt.

I suspect that they mean you can draw out the rated capacity (100 AH in this case), not every bit of amperage out of the battery. On some tables, I've seen the actual "real" capacity as 102 AH. So that may be what they are doing. Below 8 volts is kinda useless anyways, is it not? For that matter, what will run below 11 volts?

I think that if I consider getting one or two of these, then placement inside the van is a necessity. I can't imagine expending the power to run heating pads so they can be under the van. I have a spot under the banquette that may work nicely.

I'll probably mull this a bit more. An extra frame and AGM battery to put under the van is alot cheaper, and in the end, may be less to fiddle with.

Davydd · 10-27-2014, 06:48 PM

You might be right. I just wonder if they are over selling. I am a little confused on the 8 volts because I thought 10.5 volts meant 100% discharge. I'm sold somewhat on lithium ion batteries as I am going for it. I just know from my lead-acid experience that abuse is the biggest culprit. I started out with my 2005 Pleasure-way Plateau with a non-intelligent charging PD 9100 series converter and my first battery didn't last a year though I think the 6 months sitting on the dealer's lot contributed heavily. I fixed the problem with intelligent charging with a Charge Wizard 3-stage charger but then found back then they hadn't optimized it for AGM batteries and thus another quickly diminished battery. Having one house battery was another problem. I was always discharging to its limit. I had to remove the passenger seat to get at the battery so maintenance was a hard and reluctant chore maybe not done as frequently as should have been done in checking connections and water levels.

With the Great West Van my two group 31 lead-acid wet-cell batteries were still going full bore when I sold it after four seasons. With those batteries I never once, to my recollection, discharged them near their limit; and since they were much easier to access I never let the water levels go down. So they were well maintained and well monitored. Did the charging intelligence behind the setup help? I don't know if there were improvements made in that regard but it might have been possible. Maybe I just got more intelligent. A chassis battery in my vehicles never needed the attention a house battery needed in an RV.

Other than those Technomadia and Mar Azul Sailboat websites I mentioned, I haven't found much on lithium ion batteries in RVs with real experience and especially nothing in regard to Class Bs. It is new territory.

Davydd · 10-27-2014, 07:03 PM

Are we being watched? This was posted on Roadtreking:The Group within the last hour by Jim Hammill, the president of Roadtrek.

Quote:

"Hi Folks, there has been a lot of talk lately on various forums about lithium battery technology and I thought I would give you a general update on this technology for Roadtrek. Roadtrek has a few lithium systems on the road and has been working hard on developing and testing a new system specifically for Roadtreks. As you know, lithium is used for many types of systems out there, but in truth, no one has truly made it possible to use it for RV's. Why? Well the neophytes will tell you temperature of batteries is the issue, but that's not really true. Its much more complex than that. And we have been successful in designing and we are now refining those systems. But I wouldn't expect to buy one soon. Anybody can bolt parts together. We want it to work, and to last. And be reliable. And yes, RT Campskunk has a lithium unit. And it works great. And it is completely built and controlled by Roadtrek. How many amp hours does he have? So many that you would probably fall down. And that's the truth."

Where else is discussion going on?

wincrasher · 10-27-2014, 07:17 PM

Well, I posted this question on 3 other forums I frequent, so maybe they track trends. Or maybe "somebody" turned us in.

I'm sure there is some competition to build a viable "power pack" - a black box that can be purchased to do all this - batteries, charging, monitoring, etc.
Someone who can do that is going to have an edge. Perhaps develop a business to sell them to all the manufacturers - and not just of B vans.

wincrasher · 10-27-2014, 07:17 PM

Well, I posted this question on 3 other forums I frequent, so maybe they track trends. Or maybe "somebody" turned us in.

I'm sure there is some competition to build a viable "power pack" - a black box that can be purchased to do all this - batteries, charging, monitoring, etc.
Someone who can do that is going to have an edge. Perhaps develop a business to sell them to all the manufacturers - and not just of B vans.

mikes47 · 10-27-2014, 07:20 PM

Roadtrek got a mention by name above, seems reasonable that someone might have a bot watching for specific reference. That could have been the trigger.

Now we know one more thing about Campskunk's new rig. Although still with little specificity.

Mike

markopolo · 10-27-2014, 07:47 PM

I see that 0C or 32F no charging info on a few sites now.

How do you not charge the batteries when you have 3 input sources (alternator, solar, grid or generator)?

booster · 10-27-2014, 08:02 PM

Quote:

Originally Posted by markopolo

I see that 0C or 32F no charging info on a few sites now.

How do you not charge the batteries when you have 3 input sources (alternator, solar, grid or generator)?

I think the multiple sources thing one of the reasons why someone would build the safety and cutoff controls into the battery system. That way you should have more options for the various charging methods, as long as they don't interfere with each other. IIRC the Technomadia setup used a standard Magnum charger, didn't have solar yet, don't recall about alternator charging.

Davydd · 10-28-2014, 12:39 AM

The battery management will prevent you from charging with any source until the cells are above freezing. That's what Advanced RV has worked out. The Silverleaf readout shows you every single cell, its voltage and temperature. I am guessing Elite Power Systems has a controller interfacing with it and the batteries. Maybe it is more complicated than that. I just haven't sat down to get an explanation in detail.

The Smart Batteries Wincrasher is investigating have low voltage and overcharging cut offs built in but I don't see anywhere if they are smart enough to prevent you from charging when below freezing. I would think that would take an external battery management system that doesn't exist in a B if you are just going to drop a substitute lithium ion battery into your rig in place of an AGM. The battery itself seems to be able to prevent overcharging.

Belzar · 10-28-2014, 05:13 PM

My take on RT is that they got burned a bit when they announced that the etrek would have a lithium option and that didn't pan out as they expected. I suspect they'll wait till they have a comprehensively design system that is fully tested and validated before offering it again. RT did this too with a diesel heater in the CS which they also no longer offer. They are learning that while it is great to be a technology leader there are risks in moving things too quickly into the market. Campskunk's unit seems to be the initial prototype now in field trials.

Davydd · 10-28-2014, 06:50 PM

I know they originally announced lithium ion with the Etrek but I was under the impression no one actually bought one with that setup. I also see Jim Hammill stating that there can't be any retrofits with existing Roadtreks. That means the system is probably very extensively integrated throughout. In other words it is most likely not a drop in Smart Battery in place of an AGM.

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