My Interstate Lithium Battery Adventures

[LB_3]

Did AM Solar quit selling their Sinopoly battery kits?

[lewster]

They didn't quit selling them, SinoPoly has moved on to the EV industry exclusively and are no longer supporting any other users.

They left us hanging for 3 pallets of cells that were never delivered.

[amirm]

Originally Posted by lewster

Viltron's lithiums don't require banding or cell restraints as do all of the modular cells that are being sold. They even look like a real battery.

http://www.amsolarrv.com/lbats/94v-200

Do these have internal BMS? If so, then they will shut down both charging and discharging at once, e.g. at freezing temps.

I looked deep at these integrated cells as they are easier to deploy but eventually ruled them out.

BTW, I ordered my batteries. I am now fully committed to the project!

I will sketch out the design later. It is based on Solar BMS that LB_3 suggested in the first post. Took a lot of thinking to figure out an effective way to utilize it. But I *think* I am there.

With our great sunny season here, not sure when I want to take apart the whole electrical system to do this. But with a mountain of parts and pieces in my garage, it will have to be sooner than later.

[LB_3]

I want to see your schematic. I had to put my plans on hold until November. Between work, an upcoming vacation, the hitch basket I just built, college football, and a licensing exam this fall, I've run out of time.

I plan to order my batteries in August....

[Protagonist]

Originally Posted by LB_3

Between work, an upcoming vacation, the hitch basket I just built, college football, and a licensing exam this fall, I've run out of time.

Goo thing you put that vacation in there. The fun in doing nothing doesn't come from having nothing to do. It comes from having something to do and not doing it!

[InterBlog]

Originally Posted by Protagonist

Goo[d] thing you put that vacation in there. The fun in doing nothing doesn't come from having nothing to do. It comes from having something to do and not doing it!

College football is functionally the same as vacation, except football lasts one hell of a lot longer!


But LB_3 works very hard both professionally and for our family, and typically gets carte blanche on the whole football thing, all 3+ months of it. This year in particular, there won't be a peep of complaint out of me, the football widow.

[amirm]

Originally Posted by LB_3

I want to see your schematic. I had to put my plans on hold until November.

Definitely. "Peer" review would be appreciated.

[amirm]

Quick update:

Good news:
I made the entire system work per OP from IB.

Bad news:
Have to rip out the Solar BMS and re-do the wiring to use a different unit. Its external ADC is either flakey or has self destructed. Without it, it can't measure the current usage so the battery gauge is no longer functional. There are also other issues with it:

1. Due to the number of cables going to it, it really can't be remote mounted. Mounting it near the rest of the electronics will mean getting on one's knees to monitor.

2. The Wifi interface is a rather pain to use. It doesn't not download its own code. You must store the .html file locally on the phone/tablet and run that. Phone OS doesn't make this easy. I made it work eventually but it is more of a pain that just pointing the web browser at its IP address. Also, I cannot get my Windows 10 to connect to its Wifi. It simply says it can't connect even though my phone does.

3. Had one serious lock up where the unit decided the battery was no longer there and switched to USB mode. Had to power cycle it to get it back.

4. Need a beefy heatsink on it. The one I used was larger than the unit but still let it reach maximum temp with just the charging load.

5. Even though the unit was supposed to shut down at 60 degree C, it happily shut up to 62 degrees and wanted to keep going.

6. Likewise there is a current limit of 120 amps but I exceeded that at one point and again, it did not shut down.

7. It is an absolute royal pain to take ribbon cable wires (tiny gauge) and mate them to more serious wires to connect to the rest of the electrical components. I built a harness for it but never feel good about such flimsy wires controlling the heart of my electrical system. THe problem is even worse with the 20 pin connector as a) it is not supplied and b) has one millimeter spacing/small wires.

8. It is a on-off system. Should it dies, if you have not bought a second unit, you are completely out of luck. The current design is indeed discontinued as he works on a new unit to come out next year.

9. Somewhat related to above, I plan to fully document my conversion but it would be no good for many as they can't source this BMS.

10. It has a charge current limit of 100 amps. Lithium batteries can accept a ton of charge and there is no reason to have such a "low" limit.

I must say, it is a wonderful product for what it is designed for: living off-grid. Key there is that it is in a home, not vibrating or shaking like mad (so connectors not as big of an issue), and you walk by it and can verify it operating. When stuck underneath the bed/seat in our coach, and bumped like the AI can constantly, it is not a good fit.

It all worked for a couple of days though. And during that time it was a pleasure. Overnight consumption of both fridge and freezer running only brought down the capacity by 25%!

I now plan to use the BMS that I have on my battery operated Quad. With all the options it costs 3X of solar BMS but it is an industrial unit designed for EV use. Has tons of fail safe options and importantly, it is a black box with remote battery gauge. Has excellent Wifi access. It will take a few days to a week or more to get it so I am stalled at such a late stage of the project .

Wanted to get this out in case IB wants to still proceed with this unit. If so, I am happy to explain how the system worked. Overall the conversion to Lithium is a delight. It took me about 10 days of working on and off on it which included a lot of re-designing the existing system in AI.

[LB_3]

Sorry it hasn't worked out yet. Post the BMS model used on your quad. I'm planning to finally order the batteries this week.

I can't remember if I posted these earlier, but this was my intended solution for the ribbon cable nightmare:

[amirm]

Oh, I didn't mean to imply that you led me astray LB. I enjoyed playing with the device and learning to use it. If the input had not broken, my final solution would have been it.

Here is the device I will be using: http://www.orionbms.com/products/orion-bms-jr/

Once I get the new system I will outline the design.

[InterBlog]

Thanks Amirm for the detailed list above. Husband and I were discussing this yesterday before I read your latest comments. I was thinking strongly about creating a removable closet floor for this assembly, for easy access to the system. Husband was noting that, if the build goes well, we shouldn't have to worry about accessing it, therefore not necessarily a lot of effort needs to go into that. My response: "Yeah, right!" There will always be changes, modifications, troubleshooting. It's going to need to get opened up again and again.

You caught my eye with the words "heat sink". Given our previous near death experiences with the electrical converter, my intention is to put some effort into researching a fire stop material to line the chamber. Just in case.

We have to rip the thing all apart anyway - might as well do it right. LB_3 will be responsible for most of the final spec-ing and installation, but I am hoping to help out with some of the logistics and carpentry.

[amirm]

My pleasure LB. Your husband pointed the way for me, and I bushwhacked my way through the jungle .

I too ripped out everything and redid it. Indeed more hours and sweat and blood went into redoing what was already there, than the Lithium part.

I tried to negotiate a space in the closet above and lost that battle . I must say, I agree with it as the Solar BMS is not exactly what you want to stick somewhere visible.

And yes, he absolutely would want to mess with it. Lots of dials and reports in there. For a while at least you would want to adjust the lithium battery threshold voltages. I have been on my knees constantly doing that and I am paying for it with pain in my right knee. Every time I lay on the floor to work on this (all of my electrical stuff is under the bed) it reminds me of the picture you posted of someone (your husband?) laying on the floor of the AI. What a joy and easy job this would have been on a larger RV with out side enclosures for all the electronics!

[InterBlog]

They're he-ere!! Christmas in October. It will be a while before we pull this entire project to completion, but it is still moving forward.

[amirm]

Congrats!

As it turns out, I just debugged the last problem with the new BMS. It was a lot more work and surprises than I expected as the new BMS works very differently.

It is an ugly solution though. Lots of kludges to make things work. A BMS made for EVs or offline use does not make for the best system in an RV with three different charge sources.

There needs to be an integrated solution rather than trying to piece together all the bits. I have just started the design process for a new system built from scratch to do this right. It will take me some time to get it off the ground but I am determined to get there.

[amirm]

I should say the final solution though, is superb. Great to wake up from an evening of power usage and still have 75% of usable charge left! And be able to have fully charged batteries after 45 minutes of driving/idling the engine. No more worrying about power. We are much more willing to dry camp now than we were before.

[FlyFishinRVr]

Originally Posted by amirm

And be able to have fully charged batteries after 45 minutes of driving/idling the engine.

Just as a point of clarification, but doesn't it say somewhere in one of the manuals to not idle the engine longer than 20 minutes?

[amirm]

Originally Posted by FlyFishinRVr

Just as a point of clarification, but doesn't it say somewhere in one of the manuals to not idle the engine longer than 20 minutes?

I have read both 20 minutes and 30 minutes. The latter reference came from Advanced RV saying it is the EPA limit for running the engine.

But sure, use your judgement. I usually run it for 10 to 15 minutes and at nearly 100 amps/hour, it doesn't take much to build confidence that you have plenty of power then.

When I do idle the engine, I make sure to give it a good workout on the freeway or mountain road.

[InterBlog]

Originally Posted by UKDUDE

It may not be of much help to you technical gurus, but I noticed Roadtrek had put out a YouTube video on the technology they use:
https://youtu.be/LH507_7rSZE

Edit: I wish Airstream had someone like this on their development team!

Now that we are much closer to execution, I'm reviewing and re-packing my brain with necessary information. I've come to find that this excellent vid was removed from YouTube, and it doesn't seem to be on Roadtrek's website either. I don't see any video information associated with their EcoTrek news releases. Roadtrek appears to have gone dark on the issue.


If I'm having a (premature!) senior moment, and anyone else locates a copy of that vid, please re-post the link.

Now, back to what I was saying about enclosures / battery system real estate.

AMIRM, you mentioned that you were NOT going to steal closet space for your system, as we are planning on doing with ours. Physically, where and how did you achieve the install? I don't think there's much detail about that in this thread thus far, unless I missed something.

I've examined Technomadia's 3.5-year lithium review post. They have a massive vintage bus which is built like a brick outhouse, so the real estate part of the equation was a no-brainer for them. They put their equipment in a compartment which rather resembles the inside of a regular flammables cabinet. No special fire prevention measures were taken and none appear to have been called for.

I'm still thinking in terms of adding some sort of fire stop material as we enlarge the area under our closet. Research is in its infancy and I don't have a plan, or even a short list of potential solutions yet, as far as that goes. I'm interested in how Roadtrek does their installs, hence my attempt to re-access their video. Next best thing: Go look at some Roadtreks and see first-hand. I located six at a single dealer in greater Houston, all 16 and 17 model years. I'm not sure if there will be much to be learned from putting eyeballs on one or more of those, but it cannot hurt.

[amirm]

Originally Posted by InterBlog

AMIRM, you mentioned that you were NOT going to steal closet space for your system, as we are planning on doing with ours. Physically, where and how did you achieve the install? I don't think there's much detail about that in this thread thus far, unless I missed something.

I don't know that my solution to that applies to other configurations of Interstate other than our dual bunk. But in ours there was a half space lower cabinet that all it had in it was this stupid subwoofer. I say stupid because it took a ton of space and pumped its output into a closed enclosure! I shot it in the head and took it out and that small cabinet now houses 300 amp hour of lithium! I took a lot of thinking and maneuvering to get it all to fit in there. Using 100 amp hour cells that were not pre-configured like yours allowed me to get them to fit.

I am going on a business trip this week but when I come back I will document and post pictures for more.

I'm still thinking in terms of adding some sort of fire stop material as we enlarge the area under our closet.

You may be relieved to know that I sleep right on top of mine with no fire stop! With good design it is as safe or safer than lead acid. I have had two instances of lead acid batteries exploding on me, throwing acid everywhere but thankfully not on me.

Research is in its infancy and I don't have a plan, or even a short list of potential solutions yet, as far as that goes. I'm interested in how Roadtrek does their installs, hence my attempt to re-access their video.

I watched their video a few times and can explain it all. But let me see if I can find the video for you. When I post my project there won't be any information you need from them but their video does make for good inspiration.

While my custom solution won't be ready for good number of months, it will be far more advanced than anything they have done. All of these systems are kludges, theirs just less so.

[FlyFishinRVr]

Originally Posted by amirm

I have read both 20 minutes and 30 minutes. The latter reference came from Advanced RV saying it is the EPA limit for running the engine.

But sure, use your judgement. I usually run it for 10 to 15 minutes and at nearly 100 amps/hour, it doesn't take much to build confidence that you have plenty of power then.

When I do idle the engine, I make sure to give it a good workout on the freeway or mountain road.

I've read everything from early death of EGR valves to leaking oil seals as a result of idling, but the amount of time seems to be highly variable before these things can happen.

One common comment seems to be if you must idle, then a high idle is best for the health and longevity of the engine.....but then the definition of what exactly constitutes "high" idle is also debated. Sigh....

I think I'll just use the genny. That's what it's designed for......