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Orion-Tr Smart DC-DC Charger

Sunday

New Member
Hi Everyone,

My AGM battery is nearing end of life and I like to replace it with a LifePo4 80Ah battery. It is for a Marco Polo V250 2018 model.

Because the Start/Stop battery is not going to be replaced and to get a better charge for the LifePo4 battery a booster has to be installed.

My mind is set on the, Orion-Tr Smart DC-DC 12/12 30A. No moving parts meaning no sound and due to the LifePo4 battery that is much smaller there should be space available under the seat.

My question is the following, the booster charger has 4 connectors *if you take the isolated version (Not sure if a none isolated version is better)

How difficult can it be to connect?! Seems to be quite difficult as searching online didn't give me any clear answers. I understand there is a relais that connects the leisure battery and the start/stop.

Question is, where can I get the power from to use as an input for the Orion? Do I need to remove the relais or can I just extend the current battery cables as an input?

Hope you have experience and can help me that would be great and images speak a 1000 words.
 

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Samebutdifferent

Active Member
I think this is the relay you need to replace, it's towards the back of the battery box and can be seen when you remove the battery. I'm guessing one positive is from the starter battery and the other from the leisure.

Relay.jpg

You do not need the isolated version as both your source and target batteries share a negative return, that is they both share a chassis ground. So two positive and a common ground are what you need to connect to the Victron charger

Look at other threads of mine to see that I share your pain regarding info on this subject.

I'd like to fit this battery as it's the same physical size of the original and this B2B due to it's small size fan cooling means it can be fitted in a more confined space. Fan cooling isn't an issue as you'll be driving when it's operating.

What battery are you planing on fitting? Where are you thinking of installing the charger? It needs 10cms above and below for efficient cooling.

Edit: should have said hi and :Welcome: to the forum
 

Steve B

Active Member
Hello, welcome, looks like you in good hands as I can't help at all here. Is that that the expected life of our leisure battery, four years?
 

Samebutdifferent

Active Member
There is an old saying that batteries don't die they're killed. Manufactures reckon on a lifespan of around 500 cycles if discharged to 50%, at that point the battery will retain 80% of it's charge, still useable but that's not a lot left in what was already a small tank. Discharging to less than 50%, leaving the battery in a discharged state etc all damage and shorten the life of the battery. They could last a few years and be shot or go on for 6 years or more, what I do know is that in motorhome circles AGM leisure batteries aren't held in very high regard. They were developed for stop start hence the battery in the MP stating 'Starter battery' on the label, and are not a true deep cycle battery.

I'm sure that the smart alternator pumping up to 14.9v through the split charge relay can't be doing the battery any good, that's why the B2B mentioned above is much better as it regulates in the same way a a smart charger.

As a comparison LifePo4 batteries have a lifespan of 2000 cycles when discharged to 20% so the only negative about them is the cost and with regard to the MP fitting them.
 

Marc o Polo

Active Member
"There is an old saying that batteries don't die they're killed". :)

Welcome Sunday to the site, :Welcome: Steve B is right, I am in awe of SBD's technical skills, just love his posts and so generous with his knowledge. I know nothing about batteries...... Wait a minute, I do!!!! I've read SBDs posts. Thanks SBD your a whizzz and soooo appreciated.
 

Samebutdifferent

Active Member
No... No... No... I'm just an old retired guy with a mechanical engineering background, a thirst for knowledge, plenty of time to use the resource that sits at our fingertips and a pinch of OCD, well maybe a bit more than a pinch:D:D:D
 

Sunday

New Member
Thanks for the :Welcome: messages.

@Samebutdifferent
You rock! that was exactly the answer I was looking for.



So the battery is charging till 80% as usual however it doesn't hold as much charge and drains to 20% quite fast.

Besides, AGM batteries are not very efficient to begin with.
Correct me if I am wrong, a 100Ah battery you can only use up to 50% so 50ah is usable, minus 20% inefficiency tax leaves 40Ah.
Only when 100% charged. Since we mostly start with 80% charged and me killing the battery doesn’t leave much to work with.


Current status, I am planning to build in:

- Victron Orion-Tr 12/12 30 Isolated version

Isolated because I read on multiple sites and got advised by the reselling company that none-clean signals could give some errors.
Rather go for 100% here ;)

- Battery: Bulltron 80Ah, it is a bit higher in price as some competitors however the form factor is important (see history story below)
80Ah because of weight reduction, short term availability, fitting and 80Ah is enough for my purpose.

- Cables and 2x 60A fuse

Installation locations:
Option 1- Preferred option however not certain it will fit.
Next to the old AGM battery, since the Bulltron 80Ah is much smaller this in theory could fit.

Option 2- See photo, below the drivers seat (UK drivers) at the back side.

After multiple calls I found the company that did the installation on the photo.
And they are willing to help with the installation, for a price. Always good to have some experience in the mix ;)

If there are any other ideas, options or questions please let me know.

Will keep you updated.






---
A bit of history, first attempt having build in a battery by professionals:
Two weeks ago a camper company tried to build in the Votronic 12/12 30 in combination with a Liontron.
That was a disaster, after 2 hours work by 2 'experts', the message was, Sorry the battery doesn't fit. It's to high.
No worries, I gave them the correct sizes of the original AGM battery 2 months earlier. That was checked and supposed to be no problem.

Having decided to just build in the Votronic in combination with leaving the original AGM battery. That took another 5 hours.
Paid, driving of the property, the complete dashboard became red. Not a good sign ;)
So everything build to it's original state and a day wasted by an 'expert' official Votronic and Liontron dealer.

---
@Marc o Polo
I am quite sure I killed the battery more-or-less. During corona time last year I haven't charged the battery on a regular basis.
 
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Marc o Polo

Active Member
Hey, Sunday,
Reads like your post has been directed in error to me (a total ignoramus!) rather than SBD, who is the real expert! He is our technical master and guru! I'm afraid I can't even insert more than one smiley face into my post.....
 

Samebutdifferent

Active Member
Yep, 100Ah = 50Ah usable which drops with age so 40Ah is realistic for an older battery.

Your LifePo4 is safely able to discharge to 20% so 80Ah = 64Ah so you have half again as much Ah with a smaller lighter battery that has a life 4 times as long as the original fitment.:Thumbs up:

Great idea to have a smaller size physically to release space for the charger, LifePo4 are completely sealed so can be mounted in any position. I considered using the space under the driver seat (UK) behind the starter battery for the B2B. Haven't a clue how I would route the cables though.

Will you have enough space around the charger for cooling? Victron recommends 10cm above and below I believe.

You'll have highly efficient charging from the alternator with the B2B and depending on way you use your MP that may mean you don't need any hookup. If you do the charger fitted to the MP is non adjustable and the AGM profile will not be good for the LifePo4, they have a completely different algorithm charging much more quickly and don't have a float, although the BMS in it should prevent any damage.

This one will slot straight in the space when the original charger is remove and is highly adaptable.

Are you going to fit a battery monitor, not sure how the display will react the the modification. Voltage readings are no good for LifePo4 as the volts remains high then drop of the edge of a cliff, Ah readings and Ah usage are required.

Really interested in your project, you're a pioneer so keep us informed of your progress.

BTW can't see the photo, we need loads of photos:)
 

Sunday

New Member
Hey, Sunday,
Reads like your post has been directed in error to me (a total ignoramus!) rather than SBD, who is the real expert! He is our technical master and guru! I'm afraid I can't even insert more than one smiley face into my post.....
Moved to the bottom, you are now not responsible for the error ;)
 

Sunday

New Member
Good questions!


Regarding the 80Ah that should be fine as the original (old) AGM battery, only charged during driving, held up nicely for 5 days.
Mostly in summer keeping the fridge cool and sometimes winter for 3 days and 2 nights with the heater on.

Where to place the booster is still in progress, the backup plan is as the image below (hopefully this time it is visible)
The space behind the seat is open, which should give enough cooling potential. A Swiss Marco Polo owner I am in contact with has this setup build in and that seems to work well.

Charging the LifePo4 will be done completely on the Victron booster. The booster will be set up to match the LifePo4 charging specifics, in this case, 14,4V and corresponding curve to charge.
Having the LifePo4 battery connected to the existing connection could be a short term solution however having two types of batteries on the same charger is not a good idea. The BMS will protect the LifePo4 however charging will be stopped.

I will not fit in a separate battery monitor. I accepted the fact that the Marco Polo build-in monitor will go out of service or will be giving false readings. Instead, the Bulltron has a BMS with Bluetooth. With the phone you can read the charge/status etc. Same as for the Victron booster this is adjustable via Bluetooth.

2021-07-16 17_51_59-Window.png
 

Samebutdifferent

Active Member
All be comes clear, or at least clearer. The space next to the small stop/start battery as in your photo under the right hand seat is an option I've thought of. What B2B has he fitted there?

Stop:start.jpg

The LifePo4 I linked to is not smart, as yours is you don't really need a monitor as all info from both battery and B2B will be on you phone.

I have this space under the left hand seat right behind the leisure battery, unfortunately come Monday there will be a Webasto heater in there.

Webasto.jpg
 

MarioF

New Member
Gentlemen, I know this post has been dormant for a year now but it's the only information I can find regarding the instalation of a Lifepo4 battery.
I am looking at this solution from Renogy:
And the star of the show in my opinion, which handles solar & alternator charging:
https://www.renogy.com/dcc50s-12v-50a-dc-dc-on-board-battery-charger-with-mppt/

I'm looking to install the above into my 2008 Marcopolo.
My main doubt is, given that there is already a charging circuit from the alternator, does this need to be disconnected in any way so that the charging is replaced with the charging managed through the DC-DC Battery Charger?
 
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caMPike

Member
Wondering if anyone managed to swap leisure battery into LiFePo4. Thinking to do that incl battery charge from start battery and solar charge as well.
Any smart solution/advice ? Thanks
 

MarioF

New Member
Yes caMPike, I did.
I used the kit I've outlined above. The only change I made was to use the DC30 instead of the DC50. Works a treat.
 

caMPike

Member
Yes caMPike, I did.
I used the kit I've outlined above. The only change I made was to use the DC30 instead of the DC50. Works a treat.
Thanks MarioF
Where did you instaled Lifepo4 battery and charger, iso original leisure battery ?
 
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