Lithium System Upgrade (REC BMS, Victron, Other)

[Caz]

Hello all, here the partial BOM for my boat battery upgrade. I hope that it helps some with their decisions. I did not go cheap on anything, and realize that my installation is seen by some as being over the top. I don't care.

I started with Tycos but have switched to the BlueSea Remote Battery Switch based upon advice from the electrical engineer that has been my consultant on this project.
https://www.bluesea.com/products/770..._-_24V_DC_500A

Other major components include:
- 3 x Wakespeed WS500 alternator regulators. Watch this video to understand why I chose to use Balmar alternators and a custom Denso replacement for the generator from:
https://youtu.be/3uWWysz4blw?si=zHpNLokXuyhw2-um

https://ssl.whatcomelectric.com

- 3 x RecBMS with their Pre-Charge unit to control the BlueSea RBS, WiFi module
- 3 x Victron MultiPlus-II Inverter/Charger 5kVA 230 V
- 3 x Cerbo GX units
- 1800 watts of Light Leaf Carbon Composite Solar panels. These will sit on a stainless steel frame that follows the contour or my canvas but sits over it with a 1 inch air gap. It also puts no load on my canvas Bimini. https://www.lightleafsolar.com/solar-panels
- 4 x VE MPPT units to mange the solar panels
- 2 x Orion Smart Chargers to keep the GenSet and ME Starter batteries topped off
- All BlueSea and Victron Energy bus bars, fuses, Ancor wiring
- 88 CALB 230 prismatic cells (I purchased full two crates from CurrentConnected.com) - The house bank consists of 2 x batteries each using 32 cells arranged as 4P8S batteries for 920 Ah's = 1,840 Ah's. My requirements include using the house batteries to power the 24 volt, 24kw bow thruster which draws 900 amps for a few seconds so BMS that squirts amps through a few mosfets will not support the power requirements.
- The main engine start batter consists of 2P8S cells
- The Genset batter consists of 1P4S cells
- I have 4 cells as spares, but am using them for a portable 12v battery.

Worthwhile websites and good vendors:
https://www.currentconnected.com Dexter is the owner. Very knowledgable.
https://ogm-energy.com Rick has been a great resource. Be sure to check out his user forums.

I've also joined the ABYC and followed as much good advice that I can find from people like Nigel Calder. Check out his attached article on oversizing conductors.

I've also done my best to get educated:

https://www.youtube.com/@OffGridGarageAustralia

and cross referenced whenever possible with other sources of information:

- https://www.solacity.com/how-to-keep...the%20battery.

- Victron Energy community forum
https://community.victronenergy.com/index.html

- LiFePO4 Battery 101 - With Professor Jay Whitacre.

https://www.youtube.com/watch?v=QlDd3jkcxoQ&t=471s

[wholybee]

That's massive. I don't think it is overbuilt per se, as much as I think it is more power than any boat should need. If I did my math right, that is 65kW of battery storage. Are you planning electric propulsion?

You might as well skip the solar. 1.8kW of solar is far to little to charge that. Consider a large generator. 12kW should be enough.

[Caz]

My boat has 5 AC units ranging from 12k-16k BTUs. I forgot to mention, that the genset is a 17.5 kW unit. The solar is to keep the small parasitic draws at bay when at anchor and at the dock. Electricity at my marina is $.39 kWh. Normal draws are 150-550 watts - Starlink, Multiplus, MasterVolt charger and other system idle loads, 2 refrigerators, 1 freezer.

[CaptainRivet]

Originally Posted by Caz

Hello all, here the partial BOM for my boat battery upgrade. I hope that it helps some with their decisions. I did not go cheap on anything, and realize that my installation is seen by some as being over the top. I don't care.

I started with Tycos but have switched to the BlueSea Remote Battery Switch based upon advice from the electrical engineer that has been my consultant on this project.
https://www.bluesea.com/products/770..._-_24V_DC_500A

Other major components include:
- 3 x Wakespeed WS500 alternator regulators. Watch this video to understand why I chose to use Balmar alternators and a custom Denso replacement for the generator from:
https://youtu.be/3uWWysz4blw?si=zHpNLokXuyhw2-um

https://ssl.whatcomelectric.com

- 3 x RecBMS with their Pre-Charge unit to control the BlueSea RBS, WiFi module
- 3 x Victron MultiPlus-II Inverter/Charger 5kVA 230 V
- 3 x Cerbo GX units
- 1800 watts of Light Leaf Carbon Composite Solar panels. These will sit on a stainless steel frame that follows the contour or my canvas but sits over it with a 1 inch air gap. It also puts no load on my canvas Bimini. https://www.lightleafsolar.com/solar-panels
- 4 x VE MPPT units to mange the solar panels
- 2 x Orion Smart Chargers to keep the GenSet and ME Starter batteries topped off
- All BlueSea and Victron Energy bus bars, fuses, Ancor wiring
- 88 CALB 230 prismatic cells (I purchased full two crates from CurrentConnected.com) - The house bank consists of 2 x batteries each using 32 cells arranged as 4P8S batteries for 920 Ah's = 1,840 Ah's. My requirements include using the house batteries to power the 24 volt, 24kw bow thruster which draws 900 amps for a few seconds so BMS that squirts amps through a few mosfets will not support the power requirements.
- The main engine start batter consists of 2P8S cells
- The Genset batter consists of 1P4S cells
- I have 4 cells as spares, but am using them for a portable 12v battery.

Worthwhile websites and good vendors:
https://www.currentconnected.com Dexter is the owner. Very knowledgable.
https://ogm-energy.com Rick has been a great resource. Be sure to check out his user forums.

I've also joined the ABYC and followed as much good advice that I can find from people like Nigel Calder. Check out his attached article on oversizing conductors.

I've also done my best to get educated:

https://www.youtube.com/@OffGridGarageAustralia

and cross referenced whenever possible with other sources of information:

- https://www.solacity.com/how-to-keep...the%20battery.

- Victron Energy community forum
https://community.victronenergy.com/index.html
- LiFePO4 Battery 101 - With Professor Jay Whitacre.

That’s a all in, no prisoners made setup, holy cow…
These solar panels are nice but 110W solar for 782$, so 1800W is 17x782$=13294$ only for solar that’s just to top off

Just an advice from dealing with Lifepo4 since 20years:
I experienced 4P4S is problematic and always a bit hit and miss, I assume because first and last cell gets much more stress then others plus natural deviation in cells on top makes in 90% the pack at first positive terminal the lowest pack over time and if you have bad luck and that contains the weakest cell(s) that drags the whole 4P4s down. Much much better with 3p4S and then connect the main battery cable positive and negative each to the 2nd cell in the middle of the pack so loads taken as symmetrical as possible off.

I exactly have that problem now, even I know better I tried my luck and failed. I got 4 additional cells from a buddy boat 4 weeks ago he couldn’t fit (same batch matched, we bought for 5 boats cells) and thought 3p4S bank runs well within 5mV at 3.55V and the 4 just lower the load per cell by 25%. Additional they are 2nd to fifth highest capacity of all 272AH cells I have. Top balance bank and additional 4 too, then cells joined (each one per 3p pack added) to a 4P4s and the trouble started. bank gets slowly but steady out of balance and cellpack 1 starts sagging more then the 3 others. after testing over 2 weeks now to fix it I would need to route 4 cables each from each cell of the first pack to main positive busbar and same for last negative pack so the load is spread symmetrical….well easier to make 2x 2P8S banks and each route one additional cable to the main busbar and have more backup as 2 separate batteries.
Well should have known better from beginning, shortcuts always bites you in the ass…

[Caz]

Originally Posted by CaptainRivet

That’s a all in, no prisoners made setup, holy cow…
These solar panels are nice but 110W solar for 782$, so 1800W is 17x782$=13294$ only for solar that’s just to top off

Just an advice from dealing with Lifepo4 since 20years:
I experienced 4P4S is problematic and always a bit hit and miss, I assume because first and last cell gets much more stress then others plus natural deviation in cells on top makes in 90% the pack at first positive terminal the lowest pack over time and if you have bad luck and that contains the weakest cell(s) that drags the whole 4P4s down. Much much better with 3p4S and then connect the main battery cable positive and negative each to the 2nd cell in the middle of the pack so loads taken as symmetrical as possible off.

I exactly have that problem now, even I know better I tried my luck and failed. I got 4 additional cells from a buddy boat 4 weeks ago he couldn’t fit (same batch matched, we bought for 5 boats cells) and thought 3p4S bank runs well within 5mV at 3.55V and the 4 just lower the load per cell by 25%. Additional they are 2nd to fifth highest capacity of all 272AH cells I have. Top balance bank and additional 4 too, then cells joined (each one per 3p pack added) to a 4P4s and the trouble started. bank gets slowly but steady out of balance and cellpack 1 starts sagging more then the 3 others. after testing over 2 weeks now to fix it I would need to route 4 cables each from each cell of the first pack to main positive busbar and same for last negative pack so the load is spread symmetrical….well easier to make 2x 2P8S banks and each route one additional cable to the main busbar and have more backup as 2 separate batteries.
Well should have known better from beginning, shortcuts always bites you in the ass…

This is really excellent real world feedback. Thanks for sharing. I will talk to my electrical engineer, Fred about your suggestions. His credentials are pretty solid as he has done several hundred designs in the past 10 years, including off-grid, RV, and marine. He has also done numerous designs for govt. customers. I'm curious, what BMS and LiFePO4 cells are you using. Fred was very specific about using the REC BMS and CALB 230 aH cells. His company purchases full shipping containers of CALB cells directly from China and feels that these are the best quality, but I won't know what real world issues I will experience until I finish the installation sometime in January. Here is a page from the REC BMS that comments on the running cells in parallel, suggesting that heat build up is the culprit. What is interesting is that they want the balance leads to be on the end cells.

[Caz]

Originally Posted by CaptainRivet

That’s a all in, no prisoners made setup, holy cow…
These solar panels are nice but 110W solar for 782$, so 1800W is 17x782$=13294$ only for solar that’s just to top off

I forgot to mention that I was able to purchase the solar panels on sale last summer at a 40% discount. Still pricey, but not as bad as it seems on first take.

[CaptainRivet]

Originally Posted by Caz

This is really excellent real world feedback. Thanks for sharing. I will talk to my electrical engineer, Fred about your suggestions. His credentials are pretty solid as he has done several hundred designs in the past 10 years, including off-grid, RV, and marine. He has also done numerous designs for govt. customers. I'm curious, what BMS and LiFePO4 cells are you using. Fred was very specific about using the REC BMS and CALB 230 aH cells. His company purchases full shipping containers of CALB cells directly from China and feels that these are the best quality, but I won't know what real world issues I will experience until I finish the installation sometime in January. Here is a page from the REC BMS that comments on the running cells in parallel. What is interesting is that they want the balance leads to be on the end cells.

You are welcome. I done installs mainly in car audio competitions up to 1500A (crazy stuff) some RVs and boats and now since liveaboard helping for some rum kitty money or eg help with changing standing rig for help to switch to lithium banks. So no monetary interest.
How much does he charge per Calb 230AH cell?
REC is a very good choice, my no2 if money doesn‘t count…my no1 for boats is TAO‘s BMS.
That behavior has nothing to do with the BMS, I had this with various BMS REC, Electrodacus, JK, A123smart, Batrium…and various cell manufacturers.
I have now Electrodacus BMS which is special because beside typical BMS it’s the spider in the web as it’s steering all load and charge source on cell level directly with their remotes, so no high current relays that are mechanical and already failed on me several times besides very expensive. It’s open source BMS and dead cheap for 200Euro what it can do. 2nd it doesn‘t carry any current and the only limitation is the up to 1000A shunt it is using to measure in/out current. This because I use the house bank also as starter for STB engine and windlass, have a cat so in 2nd hull is another engine with a starter battery for backup.
My cells are Lishen 272AH and sourced via a friend who owns/chairman of a NPO company that’s building Powerwalls and EVs and he gets every 2nd week a container directly from Lishen and EVE factory as well as once a month one with LTO cells from Yinglong factory. Cells are grade A+ EV and matched and because I am his buddy he extra checks what I get.
We got them 2 years ago and at that time the 272AH Lishen (a tiny bit better) and 280AH EVE are the buck for the AH cells and I got a good offer from my buddy for the Lishen. Now the 304AH EVE are the goto for bucks for AH cells.
Going to 3p4S will just require a 4th REC and a 4th battery fuse and 2x battery cable otherwise no changes. And for that install that add on costs are peanuts for a lot less potential trouble…

[CaptainRivet]

Originally Posted by Caz

I forgot to mention that I was able to purchase the solar panels on sale last summer at a 40% discount. Still pricey, but not as bad as it seems on first take.

How do they perform?
Flexible are notorious for delivering around 50 till max 70% of their rating and working angle to sun is like 60 till 120 degrees so window they produce energy small, even super expensive solbian...and well die short after warranty of 2 till 5 years is over while fixed you get 25 and even 30 years warranty and real life.
Thats why i use fixed wherever possible as top notch brand they deliver often above rating, especially the bifacial ones. And prices is like 200-350Euro for 550W bifacials from Top10 companies.

[Caz]

Originally Posted by CaptainRivet

You are welcome. I done installs mainly in car audio competitions up to 1500A (crazy stuff) some RVs and boats and now since liveaboard helping for some rum kitty money or eg help with changing standing rig for help to switch to lithium banks. So no monetary interest.
How much does he charge per Calb 230AH cell?
REC is a very good choice, my no2 if money doesn‘t count…my no1 for boats is TAO‘s BMS.
That behavior has nothing to do with the BMS, I had this with various BMS REC, Electrodacus, JK, A123smart, Batrium…and various cell manufacturers.
I have now Electrodacus BMS which is special because beside typical BMS it’s the spider in the web as it’s steering all load and charge source on cell level directly with their remotes, so no high current relays that are mechanical and already failed on me several times besides very expensive. It’s open source BMS and dead cheap for 200Euro what it can do. 2nd it doesn‘t carry any current and the only limitation is the up to 1000A shunt it is using to measure in/out current. This because I use the house bank also as starter for STB engine and windlass, have a cat so in 2nd hull is another engine with a starter battery for backup.
My cells are Lishen 272AH and sourced via a friend who owns/chairman of a NPO company that’s building Powerwalls and EVs and he gets every 2nd week a container directly from Lishen and EVE factory as well as once a month one with LTO cells from Yinglong factory. Cells are grade A+ EV and matched and because I am his buddy he extra checks what I get.
We got them 2 years ago and at that time the 272AH Lishen (a tiny bit better) and 280AH EVE are the buck for the AH cells and I got a good offer from my buddy for the Lishen. Now the 304AH EVE are the goto for bucks for AH cells.
Going to 3p4S will just require a 4th REC and a 4th battery fuse and 2x battery cable otherwise no changes. And for that install that add on costs are peanuts for a lot less potential trouble…

Thanks for the information. I would love to see some pictures of the battery set up you are currently running, as I am always trying to learn as much as possible.

[Meaban]

"- 88 CALB 230 prismatic cells (I purchased full two crates from CurrentConnected.com) - The house bank consists of 2 x batteries each using 32 cells arranged as 4P8S batteries for 920 Ah's = 1,840 Ah's. My requirements include using the house batteries to power the 24 volt, 24kw bow thruster which draws 900 amps for a few seconds so BMS that squirts amps through a few mosfets will not support the power requirements."

Hi Caz, Tks for sharing.


I like the idea to avoid a bow thruster AGM bank. What is the distance between your LFP 24V house bank and thruster? And wire size?

And by the way, AFAIK the REC ABMS only provides 4 cell control , which means it doesn't check every 8 cells individually. So it checks cells 2 by 2? Or maybe you got their new REC 2Q BMS, which can manage 8-16 cells?