Merged LiFeYPO4 1000Ah Winston prismatic cells and all electric galley...

[CatNewBee]

The battery size is about right for us and what fits under the bunk. There is no space for more.

In a bigger boat with 24V systems I would think about either 8x700Ah or 8x1000Ah.

More is always better, but you have to charge it too somehow...

[Philtao]

Originally Posted by Steve_C

will definitely be using Winston cells, and I am currently strongly leaning towards the 1000ah size.
Any thoughts or suggestions?

I read somewhere that those big cells may be more sensitive to vibration and shocks (which sometime happens on a catamaran ). It does make intuitive sense that larger plates would have more chance to flex... I would be very much interested to hear opinion from someone who has already opened a Winston cell and know how / if the plates are supported other than by the edges.

For my boat and my program (live aboard away from civilization most of the time) each cell is made of two cells in parallel. Like that I have some redundancy and if a cell fails I can rebuild the bank half size until I get a replacement cell.

BTW, what BMS are you planning to install?

Sorry if that point has already been covered in this thread, but I did not have (take ) the time to read through the previous 26 pages of messages.

[alaskanviking]

CatNewBee, its been enough time since your install, how well does the REC BMS interface with the Victron gear. Victron says its compatible but i haven't seen many real life examples of the two working together.

i was planning to use a victron cerbo/venus monitor. REC was one of the few BMS's that reasonably appear to talk and play well together. there's also that new smart regulator, and id be curious if the REC can control that as well. never could find anything concrete.

Can you use the programmable relays in the Quattro or REC to run the water heater or fridge compressor when the batteries are topped off from solar?

I am leaning hard to remove propane and go in a similar electric cooking direction. I will not have the solar capacity with a monohull, but looks like i will be fitting a 800-1000AH @ 24v under the salon. how often are you topped off from solar, compared to how often you have to run engines/generator to top off? do you have backups for cooking in case of power outage?

Thank you

[Philtao]

Originally Posted by alaskanviking

Can you use the programmable relays in the Quattro or REC to run the water heater or fridge compressor when the batteries are topped off from solar?

You may want to look at the TAO BMS with 6 programmable relay outputs. Each can be activated by one or more criteria on cell voltage, temperature or SOC.
For example I turn the water heater ON when the SOC is above a minimum and turn it OFF when it gets too low.

[CatNewBee]

REC ABMS was for me the right decision. I use the 1000Ah cells, no issue with "vibrations", they are 41kg each, they do not "vibrate" more than a 130Ah GEL battery, same weight.

Integration into Victron. Possible via VeCAN. I don't NEED this, I rely on simple signals, like stop charge, stop discharge, over voltage disconnect, under voltage disconnect. I do not need DVCC and fancy software related protocols. I like the simplicity and reliability of this BMS. I use 2-wire BMS integration only into the Quattro as the biggest load and charge source. Victron MPPT controller are awesome standalone, they dont NEED integration. YMMW.

Any way, there are other solutions using Victron integration with a computer inbetween (cerbo, octo, venus, ccgx) and happy users. If you want go down that way, it's possible.


why would you pay for a smart controller, when you not use his brain, and instead just let him take orders from the BMS. It is like hiring an NASA engineer to flip burgers in McDonald's. A simple relay can do this.

[goboatingnow]

why would you pay for a smart controller, when you not use his brain, and instead just let him take orders from the BMS. It is like hiring an NASA engineer to flip burgers in McDonald's. A simple relay can do this.

There is a big difference , a microprocessor doesn’t care whether you use 1% of its capability or 90% , the NASA engineer probably has a different opinion

I use a software defined solution. To me it’s “ simple “

[newhaul]

Originally Posted by goboatingnow

There is a big difference , a microprocessor doesn’t care whether you use 1% of its capability or 90% , the NASA engineer probably has a different opinion

I use a software defined solution. To me it’s “ simple “

Your money your boat your choice

[goboatingnow]

Originally Posted by newhaul

Your money your boat your choice

Of course , merely pointing out to the relevant poster ( who was not you ) that microprocessors don’t have opinions.

[CatNewBee]

Originally Posted by goboatingnow

There is a big difference , a microprocessor doesn’t care whether you use 1% of its capability or 90% , the NASA engineer probably has a different opinion

I use a software defined solution. To me it’s “ simple “

I do know about software development, that's why I prefer hardware for critical systems, distributed systems over centralized ones, and with a manual override option.

I am not keen on debugging software in a gale.

[alaskanviking]

i am looking into the Victron network compatible system as supposedly this allows the BMS to also tell the other charge sources to stop sending power, specifically the alternator if you use the newer smart regulators. theoretically it prevents your alternator diodes from blowing if the BMS shuts off the battery on an overcharge, which also means your less likely to lose DC power from the battery until the BMS is reset or happy. there are diffrent ways to address these issues, but i was thinking the victron stuff would be easier.

the cerbo/color-gx is more to monitor power, if the BMS can connect to it via VEbus or CAN/NMEA2k than it should work with the quattro and other VEbus/NMEA2k gear. i suspect this would also let you use one of the programmable relays in the quattro or cerbo to turn on the water heater or some such if the batteries are topped off to utilize the extra power. again all in theory lol trying to figure out the best way to configure things, keep it redundant, robust, and safe ect

Thank you, your info helped

[goboatingnow]

Originally Posted by CatNewBee

I do know about software development, that's why I prefer hardware for critical systems, distributed systems over centralized ones, and with a manual override option.

I am not keen on debugging software in a gale.

That’s why I test it first and why the code is very defensive

Most hardware these days is actually embedded firmware anyway

[CaptainRivet]

Tao and Rec BMS are great but if you go above 300A continues load or charge you get into various problems switching these high currents and the relays or other switch getting very expensive.

Well suggest to use the Electrodacus BMS with Victron equipment and you don't have to worry about all this... No current flows through the BMS, no high current relays needed and no related high current issues. Instead of interrupting the charge or load current it simply switches off or on the source that creates it and this on the SOC level you want it or needed in an emergency situation. The only "relay" needed is for your orginal legacy circuit box to switch this on/off, a cheap victron battery protect in the current you need does that job.
If the BMS breaks you have a 2nd one as spare because its only 130Euro and 2nd you can just switch on or off the source on the source itself and disable the remote control. The battery is still "online". All around it was just switched off...
Different concept, perfect for high current installs.

[CaptainRivet]

If you install from scratch I would go 24V with 8x500Ah cells as current that flows is half, so all needs to be rated half and therefore mech cheaper. No issuse with the 1000Ah cells though.

[Philtao]

Originally Posted by alaskanviking

i am looking into the Victron network compatible system as supposedly this allows the BMS to also tell the other charge sources to stop sending power, specifically the alternator if you use the newer smart regulators. theoretically it prevents your alternator diodes from blowing if the BMS shuts off the battery on an overcharge, which also means your less likely to lose DC power from the battery until the BMS is reset or happy. there are diffrent ways to address these issues, but i was thinking the victron stuff would be easier.

the cerbo/color-gx is more to monitor power, if the BMS can connect to it via VEbus or CAN/NMEA2k than it should work with the quattro and other VEbus/NMEA2k gear. i suspect this would also let you use one of the programmable relays in the quattro or cerbo to turn on the water heater or some such if the batteries are topped off to utilize the extra power. again all in theory lol trying to figure out the best way to configure things, keep it redundant, robust, and safe ect

Thank you, your info helped

I fully agree with you and I believe this is a good way to have a robust, redundant and safer installation. There are a few BMS that can do that (see attached file).

I think it is important for the BMS to have multiple ranges to trigger alarms and other events so that you do not find yourself suddenly in the dark without navigation equipment and other functions that are vital for the safety of the boat. For example lets say the chargers absorption is set at 13.8v for 12v battery (3.45v per cell):

1. one cell reaches 3.45v: reduce charge voltage (CAN bus) to eventually give time for the balancer to do its work (the charger will go into float when all cells are 3.45v)
2. one cell reaches 3.55v (something is not normal as the chargers should have stopped or gone into float) warning at the chart table + shut down the charge via CAN bus - this should recover automatically when the cell voltage drops below about 3.35v
3. one cell reaches 3.60v (maybe the CAN cable has been disconnected / Cerbo setup has changed... and previous commands had no effect): command a relay to open the charge bus - for Victron Quattro, MultiPlus, MPPT, that can be done via the remote control wires (should not recover automatically and requires manual relay reset)
4. one cell reaches 3.65v (something is terribly wrong): alarm at the chart table + command a relay to isolate the battery - maybe keep vital functions powered (should not recover automatically and requires manual relay reset)

OK, this is a bit extreme and step 3 could be skipped based on your requirements and budget (consider using separate charge and load bus relays for step 4)

Regarding the control of external equipment (water heater, water maker, start of generator....) I am not sure how that would be handled by Quattro / Cerbo. This can be handled by the BMS if it has capability of multiple ranges and multiple relay outputs. Voltage may not be the most practical way to control as it varies based on load and charge current - and those equipment use / produce high current. SOC can be a good trigger for these commands IF you can trust the SOC estimated by the BMS (but that is another discussion...). For example turn on the water heater if SOC > 75%, turn it off if SOC < 50%...

[Philtao]

Originally Posted by CaptainRivet

Tao and Rec BMS are great but if you go above 300A continues load or charge you get into various problems switching these high currents and the relays or other switch getting very expensive.

Both TAO and REC BMS can remotely command external equipment either by wire or CAN bus (in addition to relays) - so no current limit.
I would add Electrodacus to the BMS comparison chart, but I have not found specifications in a clear format that correspond to the criteria in the chart (see previous post). If someone can post a link or send that information...