Advice on my 280Ah Lifepo4 configuration

gorbypark

New Member
I think it is not that difficult to explain here ;)
I know what DDP is and DAP, taxes not included but I don´t know what DPP is.
I think DPP is just a typo of DDP. According to my quick google searches, DPP in relation to logistics is "Damage Protection Plan (DPP) is an additional insurance of containers, provided by the container leasing companies to their clients. When the client pays a small daily contribution, the leasing company insures him against certain types of damage or against maintenance costs for the containers he leases.", so that more for when you are leasing a physical container.
 

Nol

New Member
Depending if your alternator is able to deliver it, you might go for the DCC1212-40 (40A version)
It's currently on sale at the German Renogy store for 130 eur

I think the 40A is more suitable for a 280Ah bank. If you ignore any available solar and plan to be able to use it in the wintertime as well, the 20A might be too slow. If you use 60Ah / day it requires 3 hours of driving to charge with a 20A.

I have gone for the 40A version, and installed a switch on my dash, so I can manually disable it if I want to (for example on a full sunny summer day, the solar will work, so no need to charge it by the alternator in a 2-3 hour drive). The sun is free, so if it takes a whole day to top-up the cells, who cares.


I think (hope) that my alternator can handle the 40A version and looking at the German price maybe it is worth to buy the 40A version
Before I order it I have to know if my alternator can handle the 40A version but as far as I can see the lowest alternator is 100A and I think my Ducato 2,3-120hp from 2011 have the 110A version
I can´t find the 20A version on the German website, like to know that.
I don´t make a manual switch on my dash but let the BMS handle that
 

DJSmiley

Solar Addict
Just contact them. When I ordered mine last year, none of the DC-DC chargers was on the German website.

I did see them on the UK site, but wasn't able to order them (NL wasn't available). Since the UK website, at that time, said 'shipping from Germany' it was likely the DE store could send it also ;)
They have added it to the German website after my request, and since it's still there

If you order it on the UK website (not sure if they allow shipping outside UK now), you can use the code WELCOME10 to get 10% off, so the 20A version would come to 102.59 GBP. (Approx 115 eur). I see now, besides UK, only Slovenia is listed, but I think you can get them to add your country as well.

Since the difference is small compared to the 40A version (as said, 130 eur at this moment) I would go for that one ;)

No problems for your alternator, the 2.3 has either a 110A or a higher one, <110A hasn't been used on the 2.3 versions of the X250
 

remedyx

New Member
I just bought 4 280ah lifepo4 cells. Which are the correct BMS units for these cells? I also thought the BMS balanced cells. I plan to buy more 280ah cells later.
 

GSXR1000

Solar Addict
I just bought 4 280ah lifepo4 cells. Which are the correct BMS units for these cells? I also thought the BMS balanced cells. I plan to buy more 280ah cells later.
I used 120a bms x 2 i don't plan on pulling more then 100a so no reason to spend extra

so my battery will be based on 280a cells.
so 8 cells 4S2P
12VDC @560AH at a C rate of 200A
 

Nol

New Member
No problems for your alternator, the 2.3 has either a 110A or a higher one, <110A hasn't been used on the 2.3 versions of the X250
Thanks this help me a lot.
UK send them to the Netherlands and S&H cost £12, the 20A was cheaper but that is over now.
I send Renogy Germany a mail so I hope to get an answer tommorow and then I order the 40A version together with the AC-DC charger.


I just bought 4 280ah lifepo4 cells. Which are the correct BMS units for these cells? I also thought the BMS balanced cells. I plan to buy more 280ah cells later.
Mine 4 x 280Ah are on the way and I also bought a 120A BMS even I prefer a 150A version because of my inverter which is 1500W otherwise so far I never pulling out more then 65A (700W hairdryer) so the 120A should be enough.
I bought this BMS and a BMS balance the cells, that is what they told me
 

Acho_303

Solar Enthusiast
Question, I saw a post on a YouTube video that said the 280 cells are not intended for mobile use because the plates are too thin. Is that true? I am trying to source a good LiFePO4 battery to replace my AGMs and thought these 280ah cells would be a great option if they can handle the paved and grated dirt roads

Also, if someone has a 3000watt inverter what size bms should they use?? 250a? I am looking at the 3000watt victron inverter for my new system
 

GSXR1000

Solar Addict
Question, I saw a post on a YouTube video that said the 280 cells are not intended for mobile use because the plates are too thin. Is that true? I am trying to source a good LiFePO4 battery to replace my AGMs and thought these 280ah cells would be a great option if they can handle the paved and grated dirt roads

Also, if someone has a 3000watt inverter what size bms should they use?? 250a? I am looking at the 3000watt victron inverter for my new system
will said the lugs are 3 small not the plates.
also you can plan on atleast 100amp per 1000w of inverter
 

Nol

New Member
I finish my LFP with the BMS and going to install it in the RV but I have a question about the Victron BP65A
Does the BP make any sense with a LFP / BMS ?
As soon as the battery is under voltage the BMS should switch off and as far as what I understand that is what the BP also do.
Maybe I am wrong so please advice me : should I install a BP ?
 

DJSmiley

Solar Addict
I don't see any reason to install a BP, since the BMS does have an undervoltage disconnect (unlike a regular lead-acid battery)

Another reason might be the current surge rating: the BP series don't like the inrush current of an inverter.
Most inverters do have a low-voltage disconnect build-in anyway.

. The short circuit protection of the BP will be activated if you try to directly connect loads with capacitors on their input (eg inverters). For that use case, please use the BP to control the remote on/off switch on the inverter, instead of disconnecting the higher power DC line

So I don't see any reason to add a BP to do the same job as the BMS does.
 

Nol

New Member
Thanks for the confirmation, same thought as I so I forget the BP
If I would install the BP I would not connect the inverter across the BP
 

Nol

New Member
After a summer of traveling I can declare that I am very happy with the LFP but to keep me happy I like to know something.
Is it normal to loos 20Ah per week when nothing is connected to the LFP just only the BMS with BT module ?
 

DJSmiley

Solar Addict
No, it's not. Self-discharge is almost none, and the BMS draw is very low.

Unless you have something else drawing current (How do you determine the 20Ah loss? - any shunt / meter also draws some power) it should be very low.
Or the balancing is enabled and active,

My van is going to winter storage next week. My Victron BMV is always connected, also with the master switch turned off. I'm going to note the left capacity when put in storage, and will report back in a month or so to see what the status is at that point.
 

Steve_S

Offgrid Cabineer, N.E. Ontario, Canada
After a summer of traveling I can declare that I am very happy with the LFP but to keep me happy I like to know something.
Is it normal to loos 20Ah per week when nothing is connected to the LFP just only the BMS with BT module ?
LFP does have a normal and expected discharge rate which is pretty slow (after 3.200Vpc) it seems to discharge faster above 3.3V per cell.
A BMS like the JBD with BT does use a few Millivots in standby mode, also if it has balancing that may also eat some juice too. Some of the JBD BMS's have "pins" where you can connect an ON/OFF switch and others have no pins, just the spot where they should be. I believe that Pins can be added to accommodate a switch. Overkill Solar has additional info in their JBD Docs. JBD itself has info up as well BUT the machine translation is really terrible. I believe that our friends at CurrentConnected / HighTechLab who also carries & sells JBD in USA also has documented this as well.

ON the Draw, unless the battery is completely disconnected (with a switch or physically unplugged) from Inverter and other possible draws there may be other things pulling a small bit of power out.

FYI: BlueTooth uses very little power but the WIFI Adapter is a PIG for Power (That's WiFi), PC-RS Adapter uses nothing extra.

Please indicate the specific BMS Make. Model & Part # and that will illicit more accurate responses.
Check also to see if your BMS has the Plug / Pins for an external switch (believe it or not, it's optional, how dumb is that). If there is no plug or exposed pins, you may have to solder on pins or wire leads.

Hope it helps, Good Luck.
Steve
 

Nol

New Member
@DJSmiley
The BMV is also off and the 20Ah loss is what I read in the app from the BMS and balancing is active

@Steve_S
I have this BMS and as far as I know without any pins
I have a mainswitch in the + cable from the LFP and I switch it off
I only have BT to read the BMS

How did I connect the LFP :
On the + are 2 cables, one to the main switch and from there to the main fuse box and the other cable to/from the Renogy DCC1212-40
The DCC1212-40 should not be the problem becaus it is disconnected until the D+ have power

Left picture is from the BMS from Sept. 16 and the right picture is from Sept. 24combine_images.jpg
 

Bud Martin

Photon Sorcerer
20Ah per week, 1 week = 168 Hours and current draw of about 120mAhr, so may be start measuring current to see what current draw at idle is.
 

Nol

New Member
The van is in the garage so next time I will do that.
By the way it was 8 days so the loss is ±104mA/h but that is also (to) much
 

Nol

New Member
I am just back from the RV and could not find so much.
The only think what took 5mA was the AC-DC from Renogy which I have permanently connected to the LFP
I disconnect it just to see if that helps.
When I left I saw on the BMS app that the capacity went down to 227Ah so that is 3Ah in 3 days
Please don´t misunderstand me I am not worried as long as I use the RV but whats happen when it is in the garage for 5-6 months during the wintertime
 

Nol

New Member
Just back from the RV and nothing has change since I disconnect the AC-DC charger from Renogy
So problem is solved.
Picture shows the different between sept.27 and today
 

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