LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

[donradcliffe]

Originally Posted by Oceanride007

^^^
Its all new to me but I am being cautious, Absorb set to 13.7, Float 13.2, No more charge on float as Terminal Voltage is higher around 13.4. So I reckon I'm down about 30 Ahr when First Mppt goes to float, insufficient oompff in the remaining Mppt to get Volts up higher, so when evening comes battery already down about 40Ahr. Of course I can reset it by using software to turn charger off and back on again. But that not solution. My tail current is set to zero. have now Limited my 100/30 to 15 Amps so both MPPT the same, will monitor tomorrow, but probably better to change panels around so that can use single MPPT.

I'm at the same point in the process you are, and will be interested in the responses. I was more aggressive because my LiFePo4 bank was free. I set the absorb to 14.1 and the float to 13.7 I did a 20 hour load test yesterday and got 100% of the rated capacity at a cutoff point of 12.0v. I set the float voltage to keep the Yandina combiner connected to the AGM start battery during float.

Did your terminal voltage ever get to 13.7? If it did, was it the voltage at the batteries or the voltage as seen by the MPPT? I note at voltage drop of 0.2v between the two when I am charging at 25 amps--it will be a lot less as the charge current tapers. What is your bank capacity?

[Ontario32]

Originally Posted by Wood

Here's a 10amp model: https://www.ebay.com/itm/30V-10A-Adj...EAAOSwz2VeevPi

This is the 30amp one I got for $85 [currently sold out]: https://www.ebay.com/p/2146314506

These are not really "lab" quality. You will want a reasonably good multimeter to double check your settings. Although the one I got tracks with my fluke meter.

Finally taking delivery of a 0-30V/0-10A power supply today. Trying to rescue a single cell and thinking 3.6V as the voltage, but what amperage should I set to? Seems like 10A should be ok (?) since my 400A/24V bank is normally charged by a 100A Mastervolt unit.

[CatNewBee]

Originally Posted by Ontario32

Finally taking delivery of a 0-30V/0-10A power supply today. Trying to rescue a single cell and thinking 3.6V as the voltage, but what amperage should I set to? Seems like 10A should be ok (?) since my 400A/24V bank is normally charged by a 100A Mastervolt unit.

Throw all you've got on it, it will stop at the set voltage.

[beckett]

CatNewBee - thank you for your help and all the materials you have posted on this forum! Your "LiFePO4 Batteries" thread is a great source of knowledge, encouragement, and help for anyone who is considering DIY lithium conversion.
I am just starting to plan a conversion on our 53ft sailboat from 8 Trojan lead-acid to Winston cell LifePo4 battery. I would like to borrow as much possible from your system and just make some adjustments for the 24V system. I would like to do things in stages as we are full-time-live-aboard ... currently in Tangier, Morocco for the last 5 months and waiting to be free and sailing again. I have some questions:
1. I am planning 8 X Winston 400 Ah in the 8S configuration. Do you think I should consider 700 Ah cells even if I don't need that much power right now ...but just in case I would need it in the future?
2. Have you used any project management to complete your planning, sourcing, and conversion? Just wondering what timeframe looks like and if this is possible to do while living on the boat? I understand that a lot of it depends on existing wiring and equipment which is very similar but still wonder if it is possible to execute and be with power while living/working on the boat?
3. Are there resellers that you used that can put together the entire package:
Winston cells, REC BMS, Latching relays, Victron Inverter ... etc? or you sourced all the components separately? Do you mind sharing?

Thank you in advance!!

[Ontario32]

We continue to limp along with one weak cell. I’ve used the power supply to periodically bring it up to the other 7, but it does discharge faster than the others. We are REALLY thankful that we have a couple of 100 ah lead acid batteries available to replace the lithium bank when it is offline due to that weak cell needing a charge. The 30V/10A variable power supply takes a long time to bring up one of these Winston 400A cells. I set it to 3.6 or 3.7 V and crank the amps, which in this unit’s case is 7 amps or so at the most. I have to re-wire the setup somewhat each time, but it sure is nice to have the back-up! The power supply runs off an inverter, which is powered by the lead acid battery pair.

[CatNewBee]

Originally Posted by beckett

CatNewBee - thank you for your help and all the materials you have posted on this forum! Your "LiFePO4 Batteries" thread is a great source of knowledge, encouragement, and help for anyone who is considering DIY lithium conversion.
I am just starting to plan a conversion on our 53ft sailboat from 8 Trojan lead-acid to Winston cell LifePo4 battery. I would like to borrow as much possible from your system and just make some adjustments for the 24V system. I would like to do things in stages as we are full-time-live-aboard ... currently in Tangier, Morocco for the last 5 months and waiting to be free and sailing again. I have some questions:
1. I am planning 8 X Winston 400 Ah in the 8S configuration. Do you think I should consider 700 Ah cells even if I don't need that much power right now ...but just in case I would need it in the future?

No problem, you can use 700Ah cells, but for a 24V system yo need a different BMS, the ABMS is 12V only, but you can use the larger one from REC.

Originally Posted by beckett

2. Have you used any project management to complete your planning, sourcing, and conversion? Just wondering what timeframe looks like and if this is possible to do while living on the boat? I understand that a lot of it depends on existing wiring and equipment which is very similar but still wonder if it is possible to execute and be with power while living/working on the boat?

No project management, this is a simple task. Measure the space, make a list of items, order and wait for delivery, bench test, wire up and enjoy.

Originally Posted by beckett

3. Are there resellers that you used that can put together the entire package:
Winston cells, REC BMS, Latching relays, Victron Inverter ... etc? or you sourced all the components separately? Do you mind sharing?

Thank you in advance!!

There is Nothnagel in Germany, he sells REC and Winston - not sure about the other parts, GWL power sells Vinston and 123BMS, cables, lugs, tools, solenoids, components for the interface must be sourced elsewhere. (Conrad, Amazon, Fraron...)

I ordered all parts online with different vendors around Europe and USA. The BlueSea ML RBS are almost half the price in the US, even with international priority shipping and import tax you save 30%. Also Victron stuff can be sourced at some discount. Winston cells can also come directly from China / HK for a better price. But it takes time until you have everything arrived. I needed 8 weeks to get all pieces together including solar.


You can live aboard and built your system in parallel, I have done it too. Prepare as much as you can upfront. I removed the house batteries from their compartment and added longer wires to the bus bars/ breaker switches and created a temporary LA bank from the batteries outside, then modified and fitted the lithium battery, built the circuit control board, wired everything up, but kept it disconnected by the solenoids and fuses, finally inserted the fuses, switched off the LA battery and on the LFP, it took 5 minutes with no power for the transition. Fridges and freezers were always running.

The 220V part of the inverter took a little longer, you must turn off AC power when working on it for safety, but it was done in a couple of days, interruptions as short as possible. I made one change at a time and could use the system again in the afternoon. It was a bigger project, because it also involved remodeling the galley, removing propane, altering the furniture, new countertop etc. During this time I used the new gear with temporary cabling for cooking or the propane grill outside. Was a lot of fun.

Take your time, do it step by step, test what you've done and proceed. Check and investigate your old wiring to see what is reusable and what needs to be done (serviced, new or replaced).

[Oceanride007]

My 12V 1000W Windlass looks like it needs replacement, am thinking of upgrading my LFP to 24Volt, I have not yet bought 3Kva inverter charger, Now my Fridges can run on 24V, my AP is still 12V but upgradable to 24V, is everything else is 12V.

So I believe Victron have a 24V to 12V power supply (2nd one for redundancy). Not sure about buck boost from 12V alternator.


Like the idea of more power in Windlass less I^2xR power losses, voltage drops in Domestic Fridge has been a issue. Need another LFP battery but with 360Ahr at 24V, inverter AC becomes possibility.



Thoughts, opinions, welcome.

[beckett]

Originally Posted by CatNewBee

No problem, you can use 700Ah cells, but for a 24V system yo need a different BMS, the ABMS is 12V only, but you can use the larger one from REC.

Take your time, do it step by step, test what you've done and proceed. Check and investigate your old wiring to see what is reusable and what needs to be done (serviced, new, or replaced).

Thank you, CNB. I am working on the list and already talked to GWL and messaged some other resellers.
I wish cruisersforum.com developed some tools to keep documentation, diagrams, and other tools to provide better support for a thread like this one. I am pretty sure you have been asked the same questions many times... Sorry, I might ask again: do you keep updated diagrams on line something like lucidchart or Visio, also, is there the complete components list of your build?

[CatNewBee]

Originally Posted by beckett

Thank you, CNB. I am working on the list and already talked to GWL and messaged some other resellers.
I wish cruisersforum.com developed some tools to keep documentation, diagrams, and other tools to provide better support for a thread like this one. I am pretty sure you have been asked the same questions many times... Sorry, I might ask again: do you keep updated diagrams on line something like lucidchart or Visio, also, is there the complete components list of your build?

Look at my thread, should be there... https://www.cruisersforum.com/forums...d.php?t=201795
Nothing dramatic changed since then.

Well, added a lot of serial data wires (VEDirect for the MPPT and BMV712, RS485 for the REC, MK2 VEBus for the Quattro) and built a CCGX clone with some own modules on RasPi, but it is just convenience for monitoring, not essential.

[beckett]

Originally Posted by CatNewBee

Look at my thread, should be there... https://www.cruisersforum.com/forums...d.php?t=201795
Nothing dramatic changed since then.

Well, added a lot of serial data wires (VEDirect for the MPPT and BMV712, RS485 for the REC, MK2 VEBus for the Quattro) and built a CCGX clone with some own modules on RasPi, but it is just convenience for monitoring, not essential.

Thank you. I have MasterVolt 3/80/24V Charger and Inverter 2500, MV Shunt 500, and MV EasyView 5. My MPPT is Victron 10/30. I was thinking of still replicating your setup with 4 ML RBS and eventually migrating to Victron 5000 Inverter.
In the first stage of my project, I was thinking to keep using MV Charger and the inverter and put the inverter on load side and the charger on the charge bus side behind ML RBS. This is will not have REC BMS integration with inverter and the charger but I will still have the ML RBS protection.
Later on, phase 2 I was going to add Viktron 5000 and possibly remove the MV inverter and replicate what you have done. What do you think this plan, anything you would change?
Also, how do you use your MV Inverter? Is it integrated in any way with your REC BMS? I can't easily find a space for the new Viktron 5000 and keep my MV 2500 inverter.

[beckett]

Originally Posted by CatNewBee

Look at my thread, should be there... https://www.cruisersforum.com/forums...d.php?t=201795
Nothing dramatic changed since then.

Well, added a lot of serial data wires (VEDirect for the MPPT and BMV712, RS485 for the REC, MK2 VEBus for the Quattro) and built a CCGX clone with some own modules on RasPi, but it is just convenience for monitoring, not essential.

Thank you. Very cool! I have done a bit of Arduino and XBee, would be great to see your CCGX clone, is it on RaspPi as well? Any of your development open source, GitHub?

[CatNewBee]

Originally Posted by beckett

Thank you. I have MasterVolt 3/80/24V Charger and Inverter 2500, MV Shunt 500, and MV EasyView 5. My MPPT is Victron 10/30. I was thinking of still replicating your setup with 4 ML RBS and eventually migrating to Victron 5000 Inverter.
In the first stage of my project, I was thinking to keep using MV Charger and the inverter and put the inverter on load side and the charger on the charge bus side behind ML RBS. This is will not have REC BMS integration with inverter and the charger but I will still have the ML RBS protection.
Later on, phase 2 I was going to add Viktron 5000 and possibly remove the MV inverter and replicate what you have done. What do you think this plan, anything you would change?
Also, how do you use your MV Inverter? Is it integrated in any way with your REC BMS? I can't easily find a space for the new Viktron 5000 and keep my MV 2500 inverter.

The MV is on the load bus on the other ML RBS, no other "integration" with the REC. But integrated with the other systems, daisy-chained with the victron using power assist.

You can even automate the MV to kick on when needed by macro programming of the free relay contacts on the Quattro.

[CatNewBee]

Originally Posted by beckett

Thank you. Very cool! I have done a bit of Arduino and XBee, would be great to see your CCGX clone, is it on RaspPi as well? Any of your development open source, GitHub?

No check in to Github yet, quick and dirty scripts and patches that fit my hardware. Yes, Raspi4B 4GB + 7" HDMI touch screen display, powered by a Amazon basics active 7 ports USB Hub (it has a 12V external power supply, so can be directly powered on board) .

[gscriba]

Undate regarding the Winston 700ah install now approx 6 months in use.
LiFePO4 is amazing! And I'm so greatful to both CNB and Andy Alford for all the encouragement and guidance.
Solar is up with 740 watts fixed over the bimini and another 500 watts in an under/over retracting configuration via harken track and cars. At anchor, 1240 watts. Wiring is complete with the exception of the VEDirect x 3 and VEDirect to USB x 1 cables, which should arrive Monday, 06/15.

Question for those using REC-ABMS and Victron.
I have a new Victron Cerbo GX and Touch 50, but for some reason the Cerbo is not detecting the REC. Battery monitor on the Cerbo is set to "automatic" and should be finding/detecting the REC-ABMS, but no show; states, "no battery monitor found". There are two CAN-bus plugs on the Cerbo, one for the REC and the other has a terminator in it. There is not other hardware yet connected to the Cerbo until the VEDirect cables arrive, but seems to me that should not matter. The Cerbo should still detect the REC-ABMS.
Suggestions? Thank you.

[CatNewBee]

did you order the Victron CAN version of the REC ABMS firmware, and follow the instructions how to set it up?

I assume, not. Because if you have it and it is enabled, it won't work without the cerbo / ccgx, it would throw a CAN BUS error, as discussed in another thread here. One of the reasons I am not a big fan of CAN BUS integrated system.