Life after RoadTrek: Ecotrek, rebuild Ecotrek module, or DIY?

[ContinuousImprovement]

Originally Posted by chris_g19

This is Rev H

Just cracked it open. Going to make a schematic.

Build quality is much better than I expected honestly, real organized, nice battery heaters. Can't wait to test the cells. Hopefully they are good and it's just the BMS that got fried. Few hundred bucks can fix this mess, but I'll be paying more than that in labor. Oh well, it's fun, and if I can post my fix experience maybe some others will attempt it too.

Probably will change it from a 4S2P system to a 2P4S so one balancer and monitor can be used for all 400AH.

And of course, add Bluetooth so I can keep a close eye on performance.

I've had Rev H and Rev L open. If you like your Rev H you'll love Rev L. The new BMS design and the whole wiring is new. All those loose cables are gone. The "data sheet" for the cells and BMS are at suiet-hacks-llc's website.

[Davydd]

Originally Posted by silverchris

Looks like a CALB cell to me, from my research when I was buying some lifepo4 cells

They aren't. CALB cells are green. I have them in my Advanced RV supplied by Elite Power Solutions.

[gregmchugh]

Have you considered any of the open source BMS options, not sure how many cells this can handle but it also includes a solar charge controller...

https://electrodacus.com

[avanti]

The spec for that Mewyeah BMS controller says that it has a CANbus interface. Can you tell whether RT was using it?

[markopolo]

Originally Posted by silverchris

Looks like a CALB cell to me, from my research when I was buying some lifepo4 cells

Maybe CALB SE series. Looks like SE200 on the barcode in one of the photos Chris posted. Link: SE200_SE Series_CALB

[Davydd]

Originally Posted by gregmchugh

ARV used them so they must be good...

Seriously, they make high quality stuff but I get the feeling that the DIY folks prefer something that is cheaper and more hackable...

They were probably the best out there when they built my van but I think they have moved onto Lithiumwerks Valence batteries and their BMS. As I mentioned at the last Advanced Fest they described their lithium battery systems as good, better and best that they offered. It seems everyone's van I've seen has opted to the Valence batteries. That's the direction I'm going. Volta is overkill for me since I rarely use or need air conditioning. The most I have ran an air conditioner at one single time in over 200,000 miles of travel is just 3 hours and that was more for the purpose of drying out the van in South Padre Island's humidity.

[Davydd]

Originally Posted by markopolo

Maybe CALB SE series. Looks like SE200 on the barcode in one of the photos Chris posted. Link: SE200_SE Series_CALB

These are Elite Power Solutions lithium batteries. They are similar cases. Don't they all come from China?

https://www.elitepowersolutions.com/...-ion-batteries

I have 16 GBS-LFMP200AH cells.

[ContinuousImprovement]

Folks in Facebook are suggesting you join https://www.facebook.com/groups/245511276385412/

We are a group trying to fix ecotrek for every owner rather than diy for one. I posted the follow in the group,

"He's wants to be master of his system and is having fun. He will have a big learning curve. Moving to another lithium vendor or rolling your own is not a panacea.
I used to tell male engineers that the woman across the bar may look perfect but you may feel a lot different once you get to know her. It's best to work things out with the lady you picked and married."


Have fun dating

[silverchris]

From my research when buying my CALB cells, the blue ones where an older battery, with the grey being the newer cell design

[gregmchugh]

Originally Posted by ContinuousImprovement

Folks in Facebook are suggesting you join https://www.facebook.com/groups/245511276385412/

We are a group trying to fix ecotrek for every owner rather than diy for one. I posted the follow in the group,

"He's wants to be master of his system and is having fun. He will have a big learning curve. Moving to another lithium vendor or rolling your own is not a panacea.
I used to tell male engineers that the woman across the bar may look perfect but you may feel a lot different once you get to know her. It's best to work things out with the lady you picked and married."


Have fun dating

Sam,

Well, any geek engineer worth their salt would go the DIY route instead of depending on KS2 given their history of design, testing, and manufacturing issues. Sure, not something for the vast majority of owners but if I had one with problems and was looking at $7000 to get two Ecotreks working with the possibility that they would still have issues in the future, I would go the DIY route too. These systems are not rocket science, they are well understood and off the shelf parts are readily available to build a system that will be easy to maintain and keep running reliably. Not being dependent on anyone else is a big advantage...

[chris_g19]

Here's the realest of it, fuse, contactors, current clamp, tons of relays.

I admire their design, but it's a little elaborate and complex, tons of parasitics. KISS. Keep it simple ......

[markopolo]

Burying everything in the box like that ends up being a real nuisance when a part fails. I say when a part fails and not if a part fails because with that many parts you kind of expect something to fail sooner or later. It's not that uncommon to have to replace an automotive type relay or a breaker or a fuse for example so it would be much easier if they were easily accessible.

It looks like the ANL fuse nut is right on top of the lug. Maybe there's split washer under to help prevent that nut from coming loose. A large base serrated flange nut looks like a better way to go - https://www.bluesea.com/support/arti...ed_Flange_Nuts

I like to have the lug make direct contact with the fuse (or battery etc.) and not put a washer in between. I want the least amount of electrical resistance. This drawing from Magnum shows the lug making direct contact with the fuse:


fuse stacking.JPG

[chris_g19]

Originally Posted by markopolo

Burying everything in the box like that ends up being a real nuisance when a part fails. I say when a part fails and not if a part fails because with that many parts you kind of expect something to fail sooner or later. It's not that uncommon to have to replace an automotive type relay or a breaker or a fuse for example so it would be much easier if they were easily accessible.

It looks like the ANL fuse nut is right on top of the lug. Maybe there's split washer under to help prevent that nut from coming loose. A large base serrated flange nut looks like a better way to go - https://www.bluesea.com/support/arti...ed_Flange_Nuts

I like to have the lug make direct contact with the fuse (or battery etc.) and not put a washer in between. I want the least amount of electrical resistance. This drawing from Magnum shows the lug making direct contact with the fuse:


Attachment 7403

Yeah I totally agree. I try to get as much surface area in contact with my connections.

In general it's such a rats nest in there, and you're right getting in there for debugging is a 2 hours+ process. It takes a while to drop this box from the vehicle because of it's weight you need to go slow and be careful.

I'm going to be replacing all the components in there, my goal is to A) reduce parasitic so I can keep it "ON" all the time and B) make it really simple (with all the same features of course).

I think the Smart 123 BMS will fit in there just fine. That leaves that whole front area for battery connect switching. I'm thinking of using a MOSFET battery switch, 100A continuous, 600A peak. They protect batteries and only use 1mA. Probably use some FETS to control the heaters as well and go 100% solid state with no mechanical components to fail. Also having the bluetooth connection will mean I can do significant diagnosis without the 2 hours of dropping the box from the chassis.

Yeah, it will be lighter, safer, more features, and better when I'm done with it. Probably going to bleed out $500-600 dollars for the upgrade, totally acceptable to the alternative!

[booster]

Originally Posted by markopolo

Burying everything in the box like that ends up being a real nuisance when a part fails. I say when a part fails and not if a part fails because with that many parts you kind of expect something to fail sooner or later. It's not that uncommon to have to replace an automotive type relay or a breaker or a fuse for example so it would be much easier if they were easily accessible.

It looks like the ANL fuse nut is right on top of the lug. Maybe there's split washer under to help prevent that nut from coming loose. A large base serrated flange nut looks like a better way to go - https://www.bluesea.com/support/arti...ed_Flange_Nuts

I like to have the lug make direct contact with the fuse (or battery etc.) and not put a washer in between. I want the least amount of electrical resistance. This drawing from Magnum shows the lug making direct contact with the fuse:


Attachment 7403

Marko makes a good point on the fuse mounting about the importance of how the stack at a connection is made. Blue Sea is really, really, specific on wanting the cable lug directly in contact with the fuse, battery, etc.


With the "normal" style fuses like shown in Marko's diagram you can catch a break if the current isn't really high because the stud will carry current. This makes the connection to both sides of the cable cable lug and can help. I have seen a lot of the fuses with a washer above or below the cable lug, usually to compensate for a too big hole in the lug compared to the stud, that didn't overheat badly. It is still not a good idea to do, though as it is asking for trouble later on if the often steel or stainless (read high resistance) washer corrodes at all.


I just went through a place where it did make a huge difference, though, on a MRBF fuse like these.





It appears that the stud on these single mount fuses doesn't carry any current at all, so all the current has to go through a narrow (1/8") ring of contact on the top and bottom of the fuse. One ring in and one ring out. On one of them that I have mounted on the positive connection of our inverter at 250 amps I noticed it got very hot while I was testing some new cooling fans on the inverter and cabinet. It was very hot, running over 150*F at only 100 amps. I discovered that somewhere along the line of in and out of the inverter over the years, I had gotten a stainless washer under he fuse so between the little ring on fuse and the lug to the inverter. This connection is a bit of reach and hard to see, and I tend to put nuts and washers back on the place the came from when I remove stuff so it is easier to get all back where it was, so I must not have gotten the washer off before installing the fuse and cable on the stud. Removed the washer and the temps fell to under 100*F. I was really surprised an the huge difference.

[Bud]

Thanks booster, I'll be careful with those fuses.

With my vintage Roadtrek 05/04 190P, the batteries in 2 different places as you know (Lousy Design), I gave up trying to figure out how to fuse them - nothing between both batteries on one side of the B to the other side of the van.

Thanks to avanti? you? ? I used those fuses, jury-rigged a way to mount it and fused both batteries. The only one out there fused? I'll remember your post, thanks again.

Bud

[booster]

Originally Posted by Bud

Thanks booster, I'll be careful with those fuses.

With my vintage Roadtrek 05/04 190P, the batteries in 2 different places as you know (Lousy Design), I gave up trying to figure out how to fuse them - nothing between both batteries on one side of the B to the other side of the van.

Thanks to avanti? you? ? I used those fuses, jury-rigged a way to mount it and fused both batteries. The only one out there fused? I'll remember your post, thanks again.

Bud

That would have been Avanti who mentioned them quite some time ago, and many of us have used them since

[gregmchugh]

Originally Posted by chris_g19

Yeah I totally agree. I try to get as much surface area in contact with my connections.

In general it's such a rats nest in there, and you're right getting in there for debugging is a 2 hours+ process. It takes a while to drop this box from the vehicle because of it's weight you need to go slow and be careful.

I'm going to be replacing all the components in there, my goal is to A) reduce parasitic so I can keep it "ON" all the time and B) make it really simple (with all the same features of course).

I think the Smart 123 BMS will fit in there just fine. That leaves that whole front area for battery connect switching. I'm thinking of using a MOSFET battery switch, 100A continuous, 600A peak. They protect batteries and only use 1mA. Probably use some FETS to control the heaters as well and go 100% solid state with no mechanical components to fail. Also having the bluetooth connection will mean I can do significant diagnosis without the 2 hours of dropping the box from the chassis.

Yeah, it will be lighter, safer, more features, and better when I'm done with it. Probably going to bleed out $500-600 dollars for the upgrade, totally acceptable to the alternative!

If you have only one battery online will a 100 amp relay be sufficient for GU charging?

[Bud]

Originally Posted by booster

That would have been Avanti who mentioned them quite some time ago, and many of us have used them since

Now recalling avanti calling them "da bomb".

[GeorgeRa]

Originally Posted by chris_g19

Here's the realest of it, fuse, contactors, current clamp, tons of relays.

I admire their design, but it's a little elaborate and complex, tons of parasitics. KISS. Keep it simple ......

Certainly not designed for maintainability.

All this stuff to manage a battery, but, coming from Roadtrek I am sure it has fault code readout capability such as short/long LED flashes or even alphanumeric display to facilitate troubleshooting, right?

I will wait until there is a complete, justifiable and maintainable Li solution on the market. I bet a few more years.

[gregmchugh]

ARV used these Tyco relays which I have purchased on eBay for good prices before (less than $100) for their lithium battery system. Something to consider...

https://www.te.com/usa-en/plp/X289x.html