Lithium/Alternator/Inverter Package from Xantrex

[Davydd]

Originally Posted by booster

Whatever, I guess I would rather let folks know of POTENTIAL issues rather than tell them all is rosy and perfect, when it may not be, and have them make an error,. It just seems a lot more honest to do it that way and let them make the choice.


When you bought the heated condo you distinctly stated it was because the ARV couldn't sit outside without a plug in, but I guess that wouldn't apply to anyone else, right?

If one cares to research I am the one that mentioned on this board probably first that you could not charge at below freezing and that lithium ion batteries can be damaged at -4F. So don't claim I am making it all rosy and perfect. I the have practical experience in this matter and not armchair speculation.

There was only one point last winter, December 20, 2016 to be exact when it briefly reached -20F, that I would absolutely had to plug in to be absolutely sure, but then in hindsight the batteries would have never gotten to -4F. This winter to date I would not have to plug into shore power. I know a lot of things about the behavior of lithium ion batteries and how they react to temperatures that you cannot get easily online.

Every house by code has a 15a outlet outside. It is not too onerous to have some common sense and plug in that is about all one has to say. If you invest in the technology and what to protect your investment common sense might tell you as well not to park in a rodent infested pole barn either.

You are letting folks know of POTENTIAL issues by sticking your nose in what you have no practical experience in.

[booster]

Originally Posted by Davydd

If one cares to research I am the one that mentioned on this board probably first that you could not charge at below freezing and that lithium ion batteries can be damaged at -4F. So don't claim I am making it all rosy and perfect. I the have practical experience in this matter and not armchair speculation.

Yep, you certainly did, and have been denying it could make any difference ever since, even though you, yourself, put the ARV in a heated condo so it couldn't get too cold, by your own statement. Opinions are just that, and I have mine that are fact based, IMO. Can you say that nobody would ever buy a lithium battery system and store in an outdoor storage lot, somewhere cold? I think not, but you can have your opinion, as that is what it is, and you are entitled to it, just like the rest of are.

Whomever may still be reading this discussion can make their own decisions and come up with their own opinions, as I am sure they are capable, and you know what, we don't get to vote on that.

[nebulight]

wow guys, lets settle down

Seriously though lets all agree that there is no perfect system. Lifepo4 has limitations, period. Lead acid has limitations, period. However a well designed system can attempt to address some of those limitations for both AGM and lifepo4. Lifepo4 requires a BMS to monitor the cells. It also has temp issues, but can be addressed with charging cut offs and heating batteries/planning ahead of cold weather storage. Maybe that's removing the batteries, heating the cells, ect. AGM has self discharge issues, agm has limited discharge abilities current draw limitations, can't discharge beyond 50% SOC. Current limitations and SOC limitation can be addressed with a properly sized group. Self discharge can be addressed with a trickle charge or solar to keep things topped off.

Know what works for your van and stick with that system. And stop arguing on the internet

[MsNomer]

Does anyone use AGM to power heating for LiFePO4?

[booster]

And as always, the 50% rule for lead acid batteries has risen from the dead

[nebulight]

Originally Posted by booster

And as always, the 50% rule for lead acid batteries has risen from the dead

Lithium can be charged below freezing, but you are not going to get max life out of them. AGMs can be discharged past 50% but you are not going to get the max life out of them. Best practice recommendations are there for a reason but you can do whatever works best for you.

[Boxster1971]

Originally Posted by cruising7388

Although I don't think it was part of their design plan, the Galleria Li3 battery layout could turn out to be a real plus in this regard. It isn't imprisoned under the chassis which would involve a major PITA for seasonal removal. It's located under the rear power sofa and easily accessible and presumably removable via the rear door. It's a 600ah brick and pretty heavy but isn't that why God made husky teenagers?

If it's the Lithionics 600A battery you will need more than husky teenagers. It weighs 150 lbs and would likely require a small hoist to remove.
http://lithionicsbattery.com/product...-case-module/?

- - Mike
2012 Sprinter 3500 Extended converted B-Van by Airstream

[GeorgeRa]

Originally Posted by nebulight

Lithium can be charged below freezing, but you are not going to get max life out of them. AGMs can be discharged past 50% but you are not going to get the max life out of them. Best practice recommendations are there for a reason but you can do whatever works best for you.

I thought that a permanent damage occurs not just reduced life if Li batteries are charged below freezing

“….Many battery users are unaware that consumer-grade lithium-ion batteries cannot be charged below 0°C (32°F). Although the pack appears to be charging normally, plating of metallic lithium can occur on the anode during a sub-freezing charge. This is permanent and cannot be removed with cycling. Batteries with lithium plating are more vulnerable to failure if exposed to vibration or other stressful conditions. Advanced chargers (Cadex) prevent charging Li-ion below freezing….”
Charging Batteries at High and Low Temperatures – Battery University

[avanti]

Originally Posted by nebulight

Lithium can be charged below freezing, but you are not going to get max life out of them.

What George says.

AGMs can be discharged past 50% but you are not going to get the max life out of them.

Not true either. When you draw *any* amps, you "use up" some lifetime. Nothing special about 50%

Best practice recommendations are there for a reason but you can do whatever works best for you.

"Best practice" and "Internet lore" are not always the same thing.

[Boxster1971]

Originally Posted by nebulight

Lithium can be charged below freezing, but you are not going to get max life out of them. AGMs can be discharged past 50% but you are not going to get the max life out of them. Best practice recommendations are there for a reason but you can do whatever works best for you.

Agreed it's well documented that taking AGMs regularly below 50% SOC will reduce their performance life. But from the information I can find on Lithiums charging below freezing and storing below -4F causes some form of permanent damage. Of course freezing an AGM also does permanent damage - just at a much lower temps.

http://batteryuniversity.com/learn/a...w_temperatures

http://lithionicsbattery.com/wp-cont...cations-R0.pdf

This is all a good discussion. Considering the power density and performance advantage of Lithium batteries they make a lot of sense in B-vans. They are bound to be more common as other manufacturers adapt them. Temp issues can be dealt with if users are aware of limitations.

Of course research continues to make Lithiums more cold tolerant.
https://spectrum.ieee.org/energywise...o-temperatures

- - Mike
2012 Sprinter 3500 Extended converted B-Van by Airstream

[avanti]

Originally Posted by Boxster1971

Agreed it's well documented that taking AGMs regularly below 50% SOC will reduce their performance life.

Yes, but so will taking it down 20%. It is just a matter of degree. The 50% thing is just a simple-minded rule of thumb.

[booster]

Originally Posted by avanti

Yes, but so will taking it down 20%. It is just a matter of degree. The 50% thing is just a simple-minded rule of thumb.

Yes.

The charts for battery life do show that you get the about 1/2 the number of lifetime charge cycles at 20% compared to 50%, but if you look at the lifetime number of AH put in and taken out, the difference is much smaller.

All battery manufacturers are different and some of the charts hard to get an accurate read on, but if you use the twice as many cycles at 50% than 20%, you get roughly the following, which can tilt both ways based on the manufacturer.

Going from 50% discharge cycles to 80% discharge gives:

20% less total AH over the life of the battery

60% more usable capacity from the same battery bank 80% usable instead of 50%

About 1/3 less battery capacity needed for the same usable capacity so 1/3 less weight and space.

For us, and likely many others, we rarely would need to go to 80% discharged, but want the capacity if we do need to. Why haul a whole bunch more batteries around for the 5% of the time we need the extra capacity? Since the discharge vs life "averages" that 5% is an extremely small factor in the life of the battery. The poor charging control that is in most class B RVs will do way, way, more damage than the deeper discharges do.

We hear all the time that you "can't discharge AGMs below 50%" which is obviously not correct. We also hear you "shouldn't discharge AGMs below 50%", which IMO is severely over stated. We also hear that even a couple of deep discharges will ruin the AGM battery. Per the manufacturers this is only true if the battery is not a true deep cycle AGM.

Personally, if you are going to run AGM and are worried about life, I would spend the money on good charging equipment way before I would buy more batteries so they would only ever be discharged to 50%.

Currently, the 50% rule is one of the big selling points for the lithium battery sellers and manufacturers that they use for cost comparison purposes, but the limited data we were able to find showed that lithium may actually suffer more from deep discharges than AGM does.

[BBQ]

Originally Posted by booster

And as always, the 50% rule for lead acid batteries has risen from the dead

Your pet peeve is as bad as David's

[booster]

Originally Posted by BBQ

Your pet peeve is as bad as David's

Now I wouldn't go quite that far , but certainly this would rate very high on my list of things that I really think folks need to hear, as it can have a big influence on camping convenience and system selections, and the misconception is so widespread it is taken as gospel.

So, I guess I would rate that statement as "somewhat true" as the fact checkers would say

[Bud]

Originally Posted by booster

Now I wouldn't go quite that far , but certainly this would rate very high on my list of things that I really think folks need to hear, as it can have a big influence on camping convenience and system selections, and the misconception is so widespread it is taken as gospel.

So, I guess I would rate that statement as "somewhat true" as the fact checkers would say

Mr. booster, you sure did assist me with your almost pet peeve.

Thanks again.

Bud

[Phoebe3]

Originally Posted by Bud

Mr. booster, you sure did assist me with your almost pet peeve.

Hear, hear! I was all wrapped around the axle thinking we needed the ever-so-expensive lithium and GU options, but the deep cell batteries we have are so cheap to buy and we may only run them down past 50% once or twice a year. It just wasn't worth worrying about and gave us a LOT more options regarding which RV we could purchase.

I DO miss being able to run the microwave to heat water for tea, though...

[kite_rider]

Back to the Lithium part of the discussion... I think we can all agree that one shouldn't charge their Li batteries below 0C; but I'm not so sure there is an issue with using or storing the batteries below 0C.

I don't have Lithium in my campervan (yet), but my bike gets used and stored in sub 0C weather all the time with zero issues to date. Same is true everyone I know who does winter e-biking. Is this just a mfg suggestion or a real issue with Lithium batteries?

[booster]

The temp things is usually stated in 3 steps for the rv style batteries, it think. 32*F for warmer for charging but usable in discharge down to the -4*F, and then not even stored at colder than that.

I think the last I heard, Tesla has some different way of stating cold use. I think it was no charging under freezing like above, but no allowable storage without being plugged in if it got below something like -22*F for 24 hours.

[kite_rider]

Interesting. Seems tough to disallow storage below -4F.

My brother owns a 2013 Model S Tesla. He's overseas about 2/3 of the year and has left his car in a parking structure (open to the elements) in the Denver area for months at a time. No issues to date with that...

[booster]

Originally Posted by kite_rider

Interesting. Seems tough to disallow storage below -4F.

My brother owns a 2013 Model S Tesla. He's overseas about 2/3 of the year and has left his car in a parking structure (open to the elements) in the Denver area for months at a time. No issues to date with that...

I would totally agree that -4*F as a limit is tough, and that is why it is also important for folks to hear about it. In the beginning there wasn't any low end storage limit that I am aware of, and the -4* came recently, as davydd said and relayed, from ARV first. We have found similar recommendations other places now, also, like the Lithiounics literature lined earlier, so likely is correct.

It would be interesting to see what your brother's manual says about cold storage, or if that is a relatively new spec for Tesla also.