Low Budget Lifepo4 Experiences anyone?

[wholybee]

Originally Posted by Franziska

Thank you!

A 250A Daly BMS with Bluetooth it is then.
Cells will form one big block.

We have those three auto load balancers (thankfully not expensive). Guess we need one of those than instead of three.
Any thoughts how I wire that up with one big block then?

Before it was three balancers with connections for 4 cells on each....

Here is how to wire it as one block. These are CALB cells, but hooked up the same way.

[mitiempo]

I decided to go with the Electrodacus. A BMS is your control but it didn't make sense to me that all the current had to pass through it. The amperage of the Electrodacus is unlimited.

Electrodacus will control any good solar controller like Victron - eg turn it off.

It will turn off any inverter that has a simple on off switch with only soldering 2 wires to the switch. If a Victron that is not necessary.

It can control any AC charger either directly or with a Victron battery protect

It will monitor state of charge, usage, charging current etc - it does much more than a Victron BMV so one is not required.

It costs $159 Cdn - about 110 Euros. It is made in Canada.

I have mine and am waiting for the Calb cells.

ps. Do not ever put a washer under a busbar as posted by CaptainRivet. A sure way to guarantee that all cells do not get the same charge/use. Wire the cells properly.

[CaptainRivet]

Originally Posted by mitiempo

I decided to go with the Electrodacus. A BMS is your control but it didn't make sense to me that all the current had to pass through it. The amperage of the Electrodacus is unlimited.

Electrodacus will control any good solar controller like Victron - eg turn it off.

It will turn off any inverter that has a simple on off switch with only soldering 2 wires to the switch. If a Victron that is not necessary.

It can control any AC charger either directly or with a Victron battery protect

It will monitor state of charge, usage, charging current etc - it does much more than a Victron BMV so one is not required.

It costs $159 Cdn - about 110 Euros.

I have mine and am waiting for the Calb cells.

ps. Do not ever put a washer under a busbar as posted by CaptainRivet. A sure way to guarantee that all cells do not get the same charge/use. Wire the cells properly.

And why not put a washer underneath the Busbar so you can tie it down evenly?
Busbar, washer, terminal, all tied together via the stud+nut and has a proper connection. What is the problem here?
How can you do it differently with the provided busbars having 3 cells in parallel, 2 in parallel and if you connect the 3rd there is a gap if you tie it down on the 3rd cell...

Electrodadacus sounds good for 110Euro. If it’s unlimited current that means it’s just measuring and controls and you have to provide all the switching relays that it operates simalar to REC and 123Smart BMS. So a full BMS then costs you easily around 500-700 Euro as the high current relays or FETs are not cheap.

[mitiempo]

Originally Posted by CaptainRivet

Electrodadacus sounds good for 110Euro. If it’s unlimited current that means it’s just measuring and controls and you have to provide all the switching relays that it operates similar to REC and 123Smart BMS. So a full BMS then costs you easily around 500-700 Euro as the high current relays or FETs are not cheap.

Electrodacus doesn't require many extra items to operate properly. In my case I will be using a Victron MPPT which it can shut off with the simple addition os a Victron interconnect cable. The inverter can be controlled directly by the Electrodacus. For shore powered charger I will use a Victron battery protect - less than 50 Euros. The Victron Orion DC to DC charger I will use for alternator charging through the Fla start battery can also be controlled by the Electrodacus directly.

Not expensive at all.

All charge sources will be set at the proper voltages so even if this were to fail there would not be an issue.

Really quite a simple system.

[mitiempo]

Originally Posted by CaptainRivet

And why not put a washer underneath the Busbar so you can tie it down evenly?
Busbar, washer, terminal, all tied together via the stud+nut and has a proper connection. What is the problem here?
How can you do it differently with the provided busbars having 3 cells in parallel, 2 in parallel and if you connect the 3rd there is a gap if you tie it down on the 3rd cell...

The washers will add resistance leading to cell imbalance. Not good.

Extra busbars may be required @ $1 each. I ordered extra with my Calb cells.

I have never seen a bank of cells that could not be connected without leaving some busbars uneven.

[CaptainRivet]

Originally Posted by mitiempo

Electrodacus doesn't require many extra items to operate properly. In my case I will be using a Victron MPPT which it can shut off with the simple addition os a Victron interconnect cable. The inverter can be controlled directly by the Electrodacus. For shore powered charger I will use a Victron battery protect - less than 50 Euros. The Victron Orion DC to DC charger I will use for alternator charging through the Fla start battery can also be controlled by the Electrodacus directly.

Not expensive at all.

All charge sources will be set at the proper voltages so even if this were to fail there would not be an issue.

Really quite a simple system.

I have all Victron too, so will really look into the Elektrodacus. That sounds really simple and effective, too simple or why are not more using this BMS?

[mitiempo]

Originally Posted by CaptainRivet

I have all Victron too, so will really look into the Elektrodacus. That sounds really simple and effective, too simple or why are not more using this BMS?

Availability most likely. It is made in small numbers by the designer, Dacian Todea in Saskatchewan. He designed it for his off grid home, where not only does he uses it with solar for basic electricity, but also to heat his house and his water for domestic use. 40F below is not uncommon where he is.

He also designed Pwm controllers to work with it - controlling up to 30 kW of panels.

His theory for off grid is a small battery bank and panels sized for the worst winter months of the year.

I will be using Victron MPPT.

https://electrodacus.com/

[Franziska]

@all
Thank you!

@more
Thank you.
Will get the "vulgaris" version. Love the expression "vulgaris" in this case. Made me laugh, but will follow your advice.

Regarding size, as we have 3 panels of 400Wp attached to 3 Epever MPPT with 40Amp each and the wind controller (Cuts out at 35A@12V) as well, we have a theoretical max charge current of:
3x40A+1x35A=155A @ 12V
Its unlikely we would ever reach this, but for safety we get the Daly 400A with fan in the non smart superior version which has a max charge current of 200A (+-20%).
Good thought?

Regarding the Rutland controller, I am aware that we may need to swap it or have it reprogrammed which Marelec already offered.

All controllers go to a common positive and a common negative rail, which then get connected to the Daly.


@wholybee
Thank you for that picture. Mighty helpful!

Regarding washers I do not see them as problematic, you have the bus bars touching the aluminium terminal plates directly. Main current goes through those plates, no?

Essentially you treat three cells as one cell and instead of balancing individuall cell elements you balance sets of three and treat them as if they where one cell.
Should one (or two) of the actual cells in any block of three fail, its block of three still delivers the full voltage, but at reduced capacity.
Wired this way we can use the one Daly 400Amp instead of three smaller ones.
Correct?

Attached a graphic all wired up with the Daly. Can anyone please confirm that this is generally correct if we use one BMS?
We will balance the individual cells before putting it all together.

Once more, thanks to all!!!! Great help!!!

Originally Posted by wholybee

Here is how to wire it as one block. These are CALB cells, but hooked up the same way.

[wholybee]

Originally Posted by Franziska

@all
Thank you![B]


Attached a graphic all wired up with the Daly. Can anyone please confirm that this is generally correct if we use one BMS?
We will balance the individual cells before putting it all together.

Once more, thanks to all!!!! Great help!!!

Yup, that looks like you got it.

[Franziska]

Thanks.

Now that the wiring is cleared up and we know which equipment we have, I have one more issue (haven't we always :-)?)

The main charger we still have is a Dometic Perfectcharge MCA 1235 (or 1250 dont remember exactly).

There are confusing infos on the web if this can be used for the LiFePo4 setup.
Does anyone know if it can be used?

If not I see the following alternatives:

Mastervolt Chargemaster 12/50-3 50A@745€

Victron Centaur 12/80-3 80A@910€

Sterling PCU 1260 60A@630€

Any thoughts on something cheaper but reliable?

I'm leaning towards the Sterling as it says specifically that it can charge LiFePo4.
The lower cost appeals too.
We could get second one later and use two if we feel a need for higher charging current.

Still, as we are mostly at anchor I hope that we can get by with our large solar+wind sources most of the time.

The charger is only needed when connected to shore power or when running the genset, higher charging current has the advantage though that we can charge more quickly and need to run the genset less.

Thanks once more, Fran

[newhaul]

Originally Posted by Franziska

Thanks.

Now that the wiring is cleared up and we know which equipment we have, I have one more issue (haven't we always :-)?)

The main charger we still have is a Dometic Perfectcharge MCA 1235 (or 1250 dont remember exactly).

There are confusing infos on the web if this can be used for the LiFePo4 setup.
Does anyone know if it can be used?

If not I see the following alternatives:

Mastervolt Chargemaster 12/50-3 50A@745€

Victron Centaur 12/80-3 80A@910€

Sterling PCU 1260 60A@630€

Any thoughts on something cheaper but reliable?

I'm leaning towards the Sterling as it says specifically that it can charge LiFePo4.
The lower cost appeals too.
We could get second one later and use two if we feel a need for higher charging current.

Still, as we are mostly at anchor I hope that we can get by with our large solar+wind sources most of the time.

The charger is only needed when connected to shore power or when running the genset, higher charging current has the advantage though that we can charge more quickly and need to run the genset less.

Thanks once more, Fran

The link will automatically download the pdf of your setup manual
And if I read correct it can be set to charge your lfp bank via dip switches

https://www.google.com/url?sa=t&sour...=1620413464916

[Franziska]

Hi Newhaul,

thanks, the problem is the "I read it correct" I have exactly the same issue.
LiFePo4 is not exactly Li-Ion.
The manual mentions Li-Ion, but not LiFePo4.

Maybe someone can shed some light on this when looking at the voltage numbers in the manual.
Unfortunately I can not...

Originally Posted by newhaul

The link will automatically download the pdf of your setup manual
And if I read correct it can be set to charge your lfp bank via dip switches

https://www.google.com/url?sa=t&sour...=1620413464916

[newhaul]

Originally Posted by Franziska

Hi Newhaul,

thanks, the problem is the "I read it correct" I have exactly the same issue.
LiFePo4 is not exactly Li-Ion.
The manual mentions Li-Ion, but not LiFePo4.

Maybe someone can shed some light on this when looking at the voltage numbers in the manual.
Unfortunately I can not...

No the iirc is more like I did read it correct.

Setting the dip switches as thus
Switch 1 to on , sets charge voltage to 14.4vdc.
Switch 2 to on sets retention voltage to 13.5vdc or off sets to 13.8vdc.
Switch 3 to off.
Switch controls the cooling fan .

[Franziska]

So that means it should work with the dipswitch settings as described below by you?

Originally Posted by newhaul

No the iirc is more like I did read it correct.

Setting the dip switches as thus
Switch 1 to on , sets charge voltage to 14.4vdc.
Switch 2 to on sets retention voltage to 13.5vdc or off sets to 13.8vdc.
Switch 3 to off.
Switch controls the cooling fan .

[newhaul]

Originally Posted by Franziska

So that means it should work with the dipswitch settings as described below by you?

That's how I read it . Yes