LifePo4-Request for advice about cell balancing?

[Dellmassive]

multi 12/1200/50



lithium battery mode:




defaults seem to be :


14.4v @ 90A





but:

charge current can be set.




and charge voltage can be set:






++++

 

[Dellmassive]

so that's all your separate chargers and profiles. . . .


now we need to work out how they all play together.

im not sure if they just all work separately,

or if there is some master control . . .

ie bluetooth VE-smart Network

 

[Samro]

are all the charge profiles set separately in each charge source?

We'll keep the DC-DC charger out of this as it is a loose cannon doing its own thing!

Charge profiles are set on the Multi and MPPT independently, but the combined charge current can be controlled using DVCC:

8. DVCC - Distributed Voltage and Current Control

www.victronenergy.com

This allows the total combined charge current of the solar and the multi to be capped.
I'll be jiggered if I can set the voltage limiter though!

 

[Dellmassive]

@Rids also has a Multiplus and multiple chargers . . .

 

[Dellmassive]

is yours a smart shunt712?

is see the DVCC has a very specific requirement list for it to work . . .



are you sure its actually working?

Victron are implying CAN coms with one of there battery's . . . .

so for it to work with ROAMER it takes data from the BMV712 or smart battery sense?




++++++++++++++++++++++++++++++++++++++++


3) DC Loads may not be accounted for, unless a SmartShunt or BMV-712 is installed and correctly configured as a DC meter.

8.4.2. Limit managed battery charge voltage​

Some batteries (like BYD and Pylontech) that come from the factory will take some time to settle in, and you may need to run them at a lower voltage for the first two weeks or so to help them balance.

This is what Limit managed battery charge voltage is designed for. Enabling this makes it possible to lower the maximum charge voltage until cells have balanced.

Do not use it for any other purpose as it may have unwanted side effects, for example, balancing can fail or not start at all if the charge voltage is set too low, causing the battery cells to become severely imbalanced over time. It is also not possible to set the value above the charge voltage limit (CVL) sent by the battery.

 

[Dellmassive]

We'll keep the DC-DC charger out of this as it is a loose cannon doing its own thing!

yep agreed . . .

thats why i sold off my ORION 12/12/30,

it gets silly hot at only 30A,

and it doesnt play with its Victron brothers, ie now VE Bus,

and even though its Bluetooth for t he APP, it doesnt receive or share VE Smart Network data . . . . . !

so all in all - not that great and has massive from for improvement form the might Victron.


out of all the dc-dc units I've tested i always go back to the Renogy DC50S (Bluetooth app & configurable)

 

[Samro]

Done some reading this morning and it seems that adjusting Absorption Voltage will always remain a feature of each individual charging component. I have established that limiting the maximum battery voltage via a GX device will never work for me because the "Limit Manager Battery Voltage Setting" is intended for use with the Victron's proprietary BMS.

Shame really and when you thing about it this is a bit daft as I would expect an override to be possible to centralise control, instead of having to dive into each components settings.

Anyway, this set me thinking - If I set my MPPT voltage slightly higher than the other charging sources, then this will ensure that solar is prioritised? Am I oversimplifying things in my mind with this comment?
I know that the top 0.6V don't have much of an effect on % SoC, so don't mind relying on the solar to provide an absolutely full charge.

 

[Rids]

@Rids also has a Multiplus and multiple chargers . . .

Indeed I do… & quickly reading through this I still have a lot to learn…

My Roamer battery also sat around without getting charged for about 6 months but seemed to recover without any warnings once installed.
I did get a fan onto the Orion, with speed control, and the heat sink is now held to 7C above the air temp in the van.

My problem with the Orion is puzzling me…
I have it controlled using the engine run signal and that seems to work fine; though I do plan to put a relay between the van signal and the Orion as I’ve seen a warning on VCDS about it. The problem is that if the LiPo isn’t fully charged then the Orion tries to top it up even when it’s all switched off… this has resulted in a completely dead starter battery twice now… last time accompanied but the van alarm going off at 02:30 on Christmas morning! At least I could put the charger on before I needed to drive at 8am!

I also have a switch between the engine run & the Orion so I only use it when I need it; so I’m currently switching that off all the time I’m not driving.
Maybe that relay would sort it…

 

[Dellmassive]

Don't forget that even when the H plus connected to an IGN feed . On the Orion.

The auto vsr feature is still active.

Ie if it sees the starter battery voltage high enough (say from solar) it will automatically switch on and start charging the leisure battery.


But saying that...

If the starter voltage drops a bit the auto vsr on feature should de activate. And switch off.

You could both screenshot your vic' Orion settings to compare....

 

[Samro]

The problem is that if the LiPo isn’t fully charged then the Orion tries to top it up even when it’s all switched off…

I don't understand! How?

Here's my DC-DC settings.
I have run the ignition feed to my H-pin from fuse 49 in fuse holder C.
I didn't bother with the Engine shutdown settings as i have them disabled.

 

[Samro]

@Rids
What fuse have you run your ignition feed from?

 

[Dellmassive]

Can you open and screenshot these tabs too,

For reference.

 

[Rids]

 

[Rids]

 

[Rids]

 

[Rids]

They’re as I have it…
I don’t recall doing the user diffused battery type though…

 

[Rids]

@Rids
What fuse have you run your ignition feed from?

Mine had a factory fitted 2nd battery and I’ve taken the wire which controlled the charging relay to the H pin. It is 12V when the engine is running.
All seems to operate as expected apart from this odd behaviour… which it doesn’t do when the switch is open… I’m beginning to think the van is doing something on that wire when it didn’t ought!

 

[Samro]

Mine had a factory fitted 2nd battery and I’ve taken the wire which controlled the charging relay to the H pin. It is 12V when the engine is running.
All seems to operate as expected apart from this odd behaviour… which it doesn’t do when the switch is open… I’m beginning to think the van is doing something on that wire when it didn’t ought!

Does the factory installed 2nd battery do some sort of random voltage sharing/paralleling of the batteries in certain conditions? I wonder if that could be some random feature of the factory setup? I'm sure one on here will be able to confirm or deny.
@mmi
@Deaky
@Loz

 

[Dellmassive]

Rids and samro have T6.1

which has a different setup to the T6.

The rest of us have a T6. (Loz has a T6 Calli which has a more advanced 3 battery setup)

 

[Dellmassive]

@Samro

Fwiw....

@Oceanis also has a T6.1

Which he now has a 3rd party leisure battery charge system.

he may be able to offer some insight.