Large Lithium BMS Set up for a Large Boat

Hello to all and to those whom will advise, a thanks in advance.

Situation:
I am about to convert my vessels house bank over from 16 Trojan T-105s (4S4P), 24v system, which served as my house and engine bank over to Lithium system.
Important side note; I have an additional two wet cell 8D's up in the bow which serve the Windlass and Bow Thruster and are charger by the engines alternator with an islation switch in line.

Moving forward:
I have just inherited/been gifted, 48 Calb CA180F 3.7 V cells which are in extremely good service condition. Included was 6 Valence XP Series U27-12XP's. They came off a 10 plus million dollar yacht, as the owner wanted to go with a new full victron system. The vessel was pretty much was a dock hotel with constant shorepower and rarely utilized the batteries while underway.

My concern:
Installation issues; First my vessel does not need so much power, so I intent to install 32 of the CALB's, retain 8 for replacement or future use and gift out the remaining 8 or maybe make a solar powered dinghy drive system..lol. Of the 32 I will Install as my house bank I want to maximize my systems ability to monitor each cells state because a fire on board is pretty much a total loss; may include loss of life if out to sea.

So my question:
Is there another way to monitor each cell other than a 4 Series/Parallel 200amp BMS? First of all, this is costly, not to mention the additon of newer charging, solar (I currently have 800 watts @ 24v of solar on board) controller and inverter. If this is the path I must take, then reccomendations on a BMS supplier would be appreciated. Note; I may go with a newer hybrid Charger, Inverter, Controller so any suggestions here would be greatly appreciated. I also have an 8KW Generator aboard, but obviously my intentions are to not use that equipment.

I'd prefer to parallel and then series for a one large battery bank, but with 4 banks of 8 cells it would be easy for an unrealized imbalanced cell or cells to arrise; thoughts?

OK, where there it is and as stated you input and or comments are greately appreciated.

Be well
Gil

My opinion is that I would not build one big bank. I would build four smaller banks for 8s4p. The 4p gives you redundancy in case something in that battery fails. That configuration would require four BMS of the simply FET-based type such as the Overkill Solar 8s 100 amp BMS. With four batteries/BMS in the bank you'll have 400 amps @ 24v to work with.

Other, much more expensive, BMS can manage the four 8s batteries with a single master device. This makes it much easier/faster to manage the batteries. Batrium is one BMS that would be used in this situation. I believe that the amp limit on a system like this is governed only by the size of contactor you use.

HRTKD, Understood and I have gone the 8s4p route... well actually 8s5p (I added another bank as back up...smile). I have reached out to Daly for their 200A 8s BMs units, with Bluetooth being the each bank of the five will can put out nominalm 180A's a bit twice under heavy loads which I should never experience due to the sharing of the loads.

I am also educating my self as far as Active Cell Balancers in the event that some do not charge/discharge equally as I get the grid operational. Any one have insight on these? I am thinking of a 2amp version just to help expidite the process. Second question about ACtive Cell Balancers is can they be wired along with the BMS? My thoughts was to get one ACB with heavy duty clamps and use as needed.

In addition I feel I will go the Daly 200A (5 of them) BMS, with Bluetooth route to help with heat disipation and wiring compatibility of the full system. Note: each of the 5 banks are actually rated at 180 amps with a 2C discharge rate; not that I will ever run with a single bank. The more banks in service the less amps draws per bank.

In speaking with Daly China, odly they reccomended a single 8S300 amp Daly??? I'm sure it is some sort of "lost in communication event" as it's been a few days of trying to clarify my layout below... That or they have created a 40 cell monitoring, 5 main, independant charge lead BMS... ???

I guess some sort of a large 5S control on pre BMS's on the drawing could help manage each of the banks, but I think if I keep all the cable sizing right I should be ok there.... Thoughts?

I reached out to Overkill to see if they were planning on making a 200a BMS, but there seems o be a snafu with communications over there as the replay back dealt with ordering and/or returns....

I haven't found a need for an active balancer. My cells are staying balanced enough using the built-in balancing from the Overkill Solar BMS.

this one? then you can connect several bms systems together

Boon, I'm hoping that will be the case with my lithiums, but being that they are used, I feel it best to have one on hand should the need arrises.

Lexio, I took a quick look at Seplos, but a bit too late; I already ordered the Daly's. Besides, Daly's cost less and seem to manufacture so many more that they should have most of the bugs worked out.

then again as in life no gaurantees

thanks for input.

gil

You appear aware of the added dangers of a fire at sea, and the need for very good cell-level management but yet make choices on BMS that are counter to those points.

1) None of the common-port BMS belong in a marine environment. Why? Because the FET's used to control the power flow are prone to failing in a closed state - therefore the BMS emergency shut down can not be counted on.

2) Better yet if it's failed closed your China BMS likely is not aware of such a situation so you get no notice until it is too late. Therefore most good BMS have double or triple level safeties (or are programable to provide this) on these emergency cut-offs. Once the emergency disconnect is open is cell voltage still climbing? Is temp still climbing? These are all things that seem trivial but important when a fire means a hole in your hull. Multi level safeties are critical.

3) In any yacht that would have a house bank as you describe it is likely a monitoring system for all critical systems is also in place. It likely speaks NMEA or perhaps a proprietary protocol. You will want the BMS to talk to that system as house bank details should be included in this monitoring.

I won't get into 8S4P versus 4P8S but really take a look at what the industry accepted standards are for large lithium packs in marine environments. It's not multiple isolated BMS's.

Jwelter so many good comments..... much appreciated and many have loomed throughout my thought process during this upgrade.

1. I have thought of a monitoring system that will link to my inhouse GSM alarm as a device input; still working on details and methodologies for this. in addition thoughts of relays/disconnects etc may come into as the system takes shape, but triggering to action need be worked through.... so just thoughts for now; I do understand the pro/con situation.

2. Base on the larger sized bank I have, I will be able to run the batteries at safer 20% to 80% range and still retail the Watts required. Doing so will permit me to establish a lower/safer high/low monitoring points for my alarm interface; more time for physical input as needed.

3. NEMA 0183/2000 interface lead to very high dollar systems (like all things nautical) such as Victron, etc. Not in the budget


8S5P... smile is due to availablity and smaller onboard charge rate, so a bank or two can be on standby for time when on shore power.....
4P8S... voltage indifference to my exsisting 24v, requires too many additons and further changes.

Before I end, I do thank you for your insight.... that said.


As a 57 year old sailor, one must accept that weather reports are not written in stone. As such we sailors, must weigh the perils of our choices and deal with the conditions we have place our vessels and/or ourselves in... weather related or otherwise. Besides sailor are much more frugal than power boaters.... smile

There are many sailors/boaters/ wannbe captains who have no clue as to what that means... I am not one of those.... smile.

be well
Gil

My Lady Stella Maris.... she is a very stable platform for Lithium... smile

nice yacht worked on jongert yachts some where in the nighty's

CapnGil said:

Jwelter so many good comments..... much appreciated and many have loomed throughout my thought process during this upgrade.

1. I have thought of a monitoring system that will link to my inhouse GSM alarm as a device input; still working on details and methodologies for this. in addition thoughts of relays/disconnects etc may come into as the system takes shape, but triggering to action need be worked through.... so just thoughts for now; I do understand the pro/con situation.

2. Base on the larger sized bank I have, I will be able to run the batteries at safer 20% to 80% range and still retail the Watts required. Doing so will permit me to establish a lower/safer high/low monitoring points for my alarm interface; more time for physical input as needed.

3. NEMA 0183/2000 interface lead to very high dollar systems (like all things nautical) such as Victron, etc. Not in the budget


8S5P... smile is due to availablity and smaller onboard charge rate, so a bank or two can be on standby for time when on shore power.....
4P8S... voltage indifference to my exsisting 24v, requires too many additons and further changes.

Before I end, I do thank you for your insight.... that said.


As a 57 year old sailor, one must accept that weather reports are not written in stone. As such we sailors, must weigh the perils of our choices and deal with the conditions we have place our vessels and/or ourselves in... weather related or otherwise. Besides sailor are much more frugal than power boaters.... smile

There are many sailors/boaters/ wannbe captains who have no clue as to what that means... I am not one of those.... smile.

be well
Gil

Click to expand...

Consider a rPi running Venus OS with the "large" image and signal-k activated. It allows a huge amount of capabilities for interfacing for under $50. It might be the easiest way to get interfaced to your GSM alarm depending on what model/make.

One thing that is consistent with "offshore folks" is they are all very proud over their expertise of the seas and knowledge, even when the Coast Guard needs to come get them out of a pickle. See it a couple times a month around here during the season. The ones that say thank you and buy the rescue crew dinner at least have learnt something, but many sulk off blaming weather/equipment/etc/etc without accepting they made those choices/calls - perhaps next time Darwin takes care of them.

On the other side of that equation I've had the luxury of working along side a sailboat designer and sailor who still holds many a record today for fastest crossings and various other metrics, but as he aged he and his wife found sailing such routes challenging so he moved to yacht design to keep their freedom a little longer. He became easier to deal with once a pair of diesels available 24/7 instead of fretting every ounce added to the overall weight (now only pounds matter).

As a side note I've never been so scared (and sick!) in my life then off the coast of NZ on the way to Key West in 20 foot swells. But going through the Panama Canal was really interesting. I totally understand the desirability of that lifestyle.

OS.... topics... Now here is where I am weakest, but knwoing so has me denoting the end result so my friends (it specialist) and brother could marry the communications aspect of this monitoring/annuciating aspect of BMS/Battery charging/GSM....

Yes some are proud, others can't fight the fear and never go, then there are many who are just too plain ignorant to the realities of the seas, but mostly the ones who find themselves in need are the ones who overestimated their capabilites and not the vessels.... Like so many situations in life each has his/her cross to bear or fence to climb. I have been in seas abeam to the waves where my vessel was lost in a trough only to be sitting high on the oncomming wave leaving me in awe of it's power.

After some 15,000 miles under my keel, I am retrofitting my vessel as noted here for one last journey before its time for me to trade her in for a MotorHome and travel the States. I will spend about 6 years traveling the world, but I am too old for a camping or a tiny house lifestyle. I will go and when I do I will go in (increased) comfort and this Lithium upgrade which will help facilitate many of the electrical needs.

Now if I can find a good woman who shares my passion..... lol.

Just kidding, us sailors have a woman in each port so look out.

CapnGil said:

OS.... topics... Now here is where I am weakest, but knwoing so has me denoting the end result so my friends (it specialist) and brother could marry the communications aspect of this monitoring/annuciating aspect of BMS/Battery charging/GSM....

Yes some are proud, others can't fight the fear and never go, then there are many who are just too plain ignorant to the realities of the seas, but mostly the ones who find themselves in need are the ones who overestimated their capabilites and not the vessels.... Like so many situations in life each has his/her cross to bear or fence to climb. I have been in seas abeam to the waves where my vessel was lost in a trough only to be sitting high on the oncomming wave leaving me in awe of it's power.

After some 15,000 miles under my keel, I am retrofitting my vessel as noted here for one last journey before its time for me to trade her in for a MotorHome and travel the States. I will spend about 6 years traveling the world, but I am too old for a camping or a tiny house lifestyle. I will go and when I do I will go in (increased) comfort and this Lithium upgrade which will help facilitate many of the electrical needs.

Now if I can find a good woman who shares my passion..... lol.

Just kidding, us sailors have a woman in each port so look out.

Click to expand...

An old saying from sailors and pilots - one of the few things they agree on.

"If it floats, flies, or f@c$s it's cheaper to rent"

@CapnGil - Welcome aboard! Just to be sure, I hope you have also visited this site for issues that may not be apparent here when you do your conversion:


Little things like not immediately smoking your alternator/regulator. And a wealth of LFP and LABC things to make life more pleasant.

Yes Substrate. I am aware, but that doesn'tmean I have worked out my solutions to such issues. I would love to go full Lithium as I have 6 Valence 138 Amp 12v batteries for Aux Engine, but these are a different composition than the 40 CALB's I just installed. I have appropriate isolation/combiners aboard and could do so if both sets happen to be equal in voltage at time of combining. Of course I would need to adapt alternator with external regulator and/or go with DC to DC charger.

As it stands now, my Aux Engine (caterpillar 3306) uses two 8D Lead Acid batteries for starting.

I may just keep the system seperate to simplify, but will install a DC to DC Charger like Vitrons Orion so I could charge the Lithiums when motoring.

This will be phase 5 of the project, but who Knows maybe someone here can direct me another way.... smile

be well
gil