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Sailboat upgrade to EVE LiFePO4 600ah @ 12v - design review

HI @captainrivet

that is very interesting, but in which case would you need such draw?
I will only have 600ah, thus I would run out of capacity in about 1 hour:eek::eek:
what is the size of your battery bank? and most importantly, size of solar array? any other chargers on board?

cheers
I have a 3p4S 816AH bank made from 12 272AH Lishen cells. I need it because I have a 3burner induction cooktop that uses 3500W (15A/230V) and a 1300W convection oven that needs 1800W from the inverter so 5300W if all runs full power. That will hardly happen but you need to spec for it, as it will happen one day. But what will happen frequently is 2500W from cooktop and 1800W oven=4300W for 15-20min.
The cooktop pulses, the oven too so you mostly see around 200-250A with sometimes goes to 300-330A. But your inverter needs to be able to handle that. Especially the convection oven is quite demanding on the inverter.

Your 600Ah and my 816AH bank are capable of handling that, you don’t run that for an hour. A normal meal is around 50-100AH of battery capacity. A typical day with breakfast, quick lunch and big dinner is around 150AH cooking and cleaning
 
I have a 3p4S 816AH bank made from 12 272AH Lishen cells. I need it because I have a 3burner induction cooktop that uses 3500W (15A/230V) and a 1300W convection oven that needs 1800W from the inverter so 5300W if all runs full power. That will hardly happen but you need to spec for it, as it will happen one day. But what will happen frequently is 2500W from cooktop and 1800W oven=4300W for 15-20min.
The cooktop pulses, the oven too so you mostly see around 200-250A with sometimes goes to 300-330A. But your inverter needs to be able to handle that. Especially the convection oven is quite demanding on the inverter.

Your 600Ah and my 816AH bank are capable of handling that, you don’t run that for an hour. A normal meal is around 50-100AH of battery capacity. A typical day with breakfast, quick lunch and big dinner is around 150AH cooking and cleaning

Hey Captain. So you're running a 12vdc house system. Is that Victron 12/3000/16 a 120vac output, or 230vac? I couldn't quite nail down the Multiplus model you're running.

I'm sure I know the answer already, but is there any compelling reason to use a 24v or 48v house system separate from the boat's 12v system? My guess is 'no'. Boat gear, for better or worse, is designed for 12v, simply because all was commonly available for decades were 6 and 12v batteries. Converting the boat systems therefore wouldn't any make sense. I read a post of one guy who considered converting his boat system, but said it would cost thousands to do it -- hardly worth the cost.

However, the AC 'house' system with the 3500+ watt cooking loads you mentioned could benefit from a 24v or 48vdc inverter to reduce those DC current and wire sizes. But I assume your battery to inverter runs are very short, so it may not be an issue for you.

What's your typical DC current draw again when you're at max AC power load? Did I read 200 amps earlier? I'd expect even more amps if all those appliances are on and you're loads are 5300 Watts (more like 450 amps!).
 
Can you tell me the make/model of your induction plate?
For boat use you may want to look at the Kenyon 'Silken 2' built in cook-top
edit: Home depot has them for a price under list.
 
Hi @captainrivet

that sounds great, how do you recharge that bank?

Hi @BobR

Thanks!!! I have been trying to find out the cooker that sv Delos was using, and they didn't seem to be sharing the manufacturer, yet, you have just pointed it out!

Cheers
 
I just want to add my 2 cents. I'm a liveaboard doing a world circumnavigation on a 55ft monohull with my kids. I built a 24V 840Ah EVE cells battery. My advise is to keep it as simple as possible as the battery and power system is actually a thing you want to build and forget.

I choose the Batrium BMS (cost about 1000USD) and all other equipment is Victron. The boat has an 11kW generator, and I've a Quattro 120A charger / inverter and a Skylla i 100A charger. So I charge at around 200A. A Cerbo GX with display is used as central hub. The alternator is controlled by a Wakespeed WS500.

Some advice from living 8 months on board:
  • If possible use CANBus to communicate. The Batrium BMS is fully compatible and shows all information on the GX display. The system uses DVCC so the BMS is in charge of communicating to the chargers and sets their voltage /amps. This is more advanced than you would think. The Batrium BMS can balance each cell with 2A, so when balancing is needed it lowers the amps of the charger to a much lower value to be sure it can be burnt off.
  • Check how your BMS triggers balancing. There are multiple strategies (above a certain cell voltage, auto levelling during charging based on voltage difference, ...). If you balance incorrectly or with to much current, you'll be inefficiënt and burn off a lot of heat. Chargers have no clue on balancing, so forget "bulk, float, storage, ..." modes. The BMS should be in charge and the whole system has to be aligned properly.
  • Not all equipment can talk through canBUS (eg Victron Skylla-i). There you'll need a hardware shutoff wire. This trip should be at a lower level than the big critical shutoff. If not, you're alternator will spike the voltage for a split second and it will destroy your equipment.
  • Charge / discharge relays won't work with Multiplus / Quattro chargers/inverters as they both charge and discharge
  • Hardware issues:
    • Most BMS measure voltage on each cell. These measurements have inaccuracies and can drift over time.
    • Does the BMS allow for voltage recalibration or voltage offset? (Batrium does)
    • What will you do if a cell runs away, take spare cells with you on the boat as you cannot fly them in. I made this mistake and can only get spare cells through shipment on a ship. These cells are not allowed on planes (even cargo).
    • Same for BMS hardware. I have 20% spare "blockmons" with me. These are the distributed cell monitors that report to the central Baterium Watchmon unit.
  • You need to protect the system on multiple levels:
    • Cell level: voltage (will you measure each cell, or will there be cells paralleled)
    • Shunt level: voltage and amps (you need to protect the max amp draw to protect your contactors, eg max 500A)
    • Heat: you need to monitor balancing heat, the BMS will need to be configured to allow for external fans to be activated
    • ...
  • The Batrium has several layers of protection than can all be configured. In my setup:
    • @ 3.5V balancing starts, output amps of charger is reduced to allow for dissapating heat. If you're not using canbus, the charger will keep pumping full amps into the battery.
    • @ 3.6V charging is stopped, this is communicated through CANBUS and through a relay to shutoff the "dump" equipment
    • @ 3.65V critical stop is triggered, and this shuts the big 500A continuous relay at the bank itself
 
I just want to add my 2 cents. I'm a liveaboard doing a world circumnavigation on a 55ft monohull with my kids. I built a 24V 840Ah EVE cells battery. My advise is to keep it as simple as possible as the battery and power system is actually a thing you want to build and forget.

I choose the Batrium BMS (cost about 1000USD) and all other equipment is Victron. The boat has an 11kW generator, and I've a Quattro 120A charger / inverter and a Skylla i 100A charger. So I charge at around 200A. A Cerbo GX with display is used as central hub. The alternator is controlled by a Wakespeed WS500.

Some advice from living 8 months on board:
  • If possible use CANBus to communicate. The Batrium BMS is fully compatible and shows all information on the GX display. The system uses DVCC so the BMS is in charge of communicating to the chargers and sets their voltage /amps. This is more advanced than you would think. The Batrium BMS can balance each cell with 2A, so when balancing is needed it lowers the amps of the charger to a much lower value to be sure it can be burnt off.
  • Check how your BMS triggers balancing. There are multiple strategies (above a certain cell voltage, auto levelling during charging based on voltage difference, ...). If you balance incorrectly or with to much current, you'll be inefficiënt and burn off a lot of heat. Chargers have no clue on balancing, so forget "bulk, float, storage, ..." modes. The BMS should be in charge and the whole system has to be aligned properly.
  • Not all equipment can talk through canBUS (eg Victron Skylla-i). There you'll need a hardware shutoff wire. This trip should be at a lower level than the big critical shutoff. If not, you're alternator will spike the voltage for a split second and it will destroy your equipment.
  • Charge / discharge relays won't work with Multiplus / Quattro chargers/inverters as they both charge and discharge
  • Hardware issues:
    • Most BMS measure voltage on each cell. These measurements have inaccuracies and can drift over time.
    • Does the BMS allow for voltage recalibration or voltage offset? (Batrium does)
    • What will you do if a cell runs away, take spare cells with you on the boat as you cannot fly them in. I made this mistake and can only get spare cells through shipment on a ship. These cells are not allowed on planes (even cargo).
    • Same for BMS hardware. I have 20% spare "blockmons" with me. These are the distributed cell monitors that report to the central Baterium Watchmon unit.
  • You need to protect the system on multiple levels:
    • Cell level: voltage (will you measure each cell, or will there be cells paralleled)
    • Shunt level: voltage and amps (you need to protect the max amp draw to protect your contactors, eg max 500A)
    • Heat: you need to monitor balancing heat, the BMS will need to be configured to allow for external fans to be activated
    • ...
  • The Batrium has several layers of protection than can all be configured. In my setup:
    • @ 3.5V balancing starts, output amps of charger is reduced to allow for dissapating heat. If you're not using canbus, the charger will keep pumping full amps into the battery.
    • @ 3.6V charging is stopped, this is communicated through CANBUS and through a relay to shutoff the "dump" equipment
    • @ 3.65V critical stop is triggered, and this shuts the big 500A continuous relay at the bank itself
Are you by chance on Facebook? I am also a circumnavigator and like to follow others. s/v Eliana.
I second the statement about simplicity. To me, that means an integrated BMS that uses FETs instead of relays. I use overkill solar. I don't think the BMS should control charging because it adds complexity, and you defeat the concept of the BMS being a last line of defense-it becomes the only line. All of my charging sources are programmed for LiFePO4.
There are some valid reasons for the BMS to control charging though, and huge loads like 4kw+ for cooking is one of them. Large loads require more balancing, especially if the cells are not perfectly matched. But for my ~1kw load it isn't necessary.
Once a month, i launch the bms app on my phone. I see the SOC is very close to the same as my Victron meter, that no disconnects have happened (none ever, in over a year) and that my cells are all still in balance.
Otherwise, zero maintenance. It's the best upgrade ive made.

Fair winds!
 
Nuwave Pic Gold
Good one. Nuwave also has a 1800W dual burner model that diverts it power needs between the 2burners and doesn‘t exceed 1800W in total….sadly only 120V US…my cat is 230V. Cannot find link at the Moment. Best for a mono as it also fits on top of gimbal stove.
 
I just want to add my 2 cents. I'm a liveaboard doing a world circumnavigation on a 55ft monohull with my kids. I built a 24V 840Ah EVE cells battery. My advise is to keep it as simple as possible as the battery and power system is actually a thing you want to build and forget.

I choose the Batrium BMS (cost about 1000USD) and all other equipment is Victron. The boat has an 11kW generator, and I've a Quattro 120A charger / inverter and a Skylla i 100A charger. So I charge at around 200A. A Cerbo GX with display is used as central hub. The alternator is controlled by a Wakespeed WS500.

Some advice from living 8 months on board:
  • If possible use CANBus to communicate. The Batrium BMS is fully compatible and shows all information on the GX display. The system uses DVCC so the BMS is in charge of communicating to the chargers and sets their voltage /amps. This is more advanced than you would think. The Batrium BMS can balance each cell with 2A, so when balancing is needed it lowers the amps of the charger to a much lower value to be sure it can be burnt off.
  • Check how your BMS triggers balancing. There are multiple strategies (above a certain cell voltage, auto levelling during charging based on voltage difference, ...). If you balance incorrectly or with to much current, you'll be inefficiënt and burn off a lot of heat. Chargers have no clue on balancing, so forget "bulk, float, storage, ..." modes. The BMS should be in charge and the whole system has to be aligned properly.
  • Not all equipment can talk through canBUS (eg Victron Skylla-i). There you'll need a hardware shutoff wire. This trip should be at a lower level than the big critical shutoff. If not, you're alternator will spike the voltage for a split second and it will destroy your equipment.
  • Charge / discharge relays won't work with Multiplus / Quattro chargers/inverters as they both charge and discharge
  • Hardware issues:
    • Most BMS measure voltage on each cell. These measurements have inaccuracies and can drift over time.
    • Does the BMS allow for voltage recalibration or voltage offset? (Batrium does)
    • What will you do if a cell runs away, take spare cells with you on the boat as you cannot fly them in. I made this mistake and can only get spare cells through shipment on a ship. These cells are not allowed on planes (even cargo).
    • Same for BMS hardware. I have 20% spare "blockmons" with me. These are the distributed cell monitors that report to the central Baterium Watchmon unit.
  • You need to protect the system on multiple levels:
    • Cell level: voltage (will you measure each cell, or will there be cells paralleled)
    • Shunt level: voltage and amps (you need to protect the max amp draw to protect your contactors, eg max 500A)
    • Heat: you need to monitor balancing heat, the BMS will need to be configured to allow for external fans to be activated
    • ...
  • The Batrium has several layers of protection than can all be configured. In my setup:
    • @ 3.5V balancing starts, output amps of charger is reduced to allow for dissapating heat. If you're not using canbus, the charger will keep pumping full amps into the battery.
    • @ 3.6V charging is stopped, this is communicated through CANBUS and through a relay to shutoff the "dump" equipment
    • @ 3.65V critical stop is triggered, and this shuts the big 500A continuous relay at the bank itself
Jan,
Thanks for your real life feedback. Also 100% lifeaboard on a 10years World circumnavigation.
Batrium is a great BMS but also very expensive.
A lot of good and valuable points here.
Some comments:
Multiplus/Quattro: you can switch on/off charger with remote control AUX1 and inverter with AUX2, instead a massive relay/SSR you just use a 5Euro small optocopler to cut in LCV or HCV event.
Spare cells: well a 2 sided sword…you need to keep them at 20-40SOC and they won‘t fit with the rest of the pack as this degrades while spare is lying around unused. My solution is stay 12V (high current loads are within cable length of 60cm from the bank) as 4 cells in series drift apart much less then 8, if you then also parallel cells you multiply chances to drift. also if 1 or 3 cell dies I only loose capacity of 4 cells. 2nd part of my solution is oversize the bank and use your spare eg enough is 560AH for me but I added 4 more to 3p4S 816AH (Lishen grade A 272AH, has 1C rate compared to EVE with 0.5C), so I have 4 spares and if one or till 4 cells run off I just reconfigure the bank. Also lowers the c-rate per cell for discharge. From experience for a 24V system I would not parallel cells and get 8 Winston cells in the capacity needed.
Hardware:
Cell voltage inaccuracies and drifting: even the cheapest BMS measure the cell voltages correctly, that’s kindergarten even for a cheap Daly. If you have inaccuracies then something is definitely wrong at the heart of your system and it’s Bad practice to correct that with the BMS…you need to fix it. Contact or oxidation/corrosion issue
- bad crimp of the sensing wire lugs is issue no1. These are often tiny wires, make sure you have the right tinned ! lugs for that cable size. After crimping you can solder only!!! the side facing inwards to the lug with a tiny! bit of tin to the lug to make sure it has proper contact. The other crimped end need to stay flexibel, no tin here at all!
- 2nd bad contact of the lug with the busbar, only use tinned lugs and tinned or silver plated Cooper busbars…the supplied ones are crap.
- 3rd issue these cells have Alu terminal that immediately oxidize at air and this oxide on Alu is very hard and bad conductive. Same applies to the cheap Alu busbars(See 2)…you need to sand with 2000grid wet or black scotchbride and then clean with 99%, after this put No-OX-AL or similar to insure good contact while air is sealed off to prevent oxcidation.
- 4th issue: Cooper busbar,sensing lug, serrated flange nut…no washers. Nut tightened to manufacturer of cells spec…EVE i think 8nm, check please. Secure nut with a drop of any nail polish available (from wife, girlfriend or get cheapest at supermarket).
- 5th issue: if sensing wire is not supplied, use tinned stranded marine grade wire and all wires from the same coil and exactly the same length.
If drifting cell measurements over time you have a contact issue, mostly oxidation or corrosion over time, again fix and NOT correct it with the BMS.
1) your bank is in salty marine environment, so your battery box has to be air tight
2) use no-OX-AL on all Alu surfaces in contact
3) bad contact see 4) above, only busbar, lug and serrated flange nut and re tighten the nut to highest allowed spec and secure with nail polish. no loctide here!!!, the nail polish stays flexible and fixes the nut but if you apply slight force it breaks much easier then loctide
4) seal from air/humidity busbar, stud, lug, I use liquide rubber product called plastidip that can be easily pulled off if you need to

BMS parameters: for liveaboard circumnavigation from a safety standpoint I find your settings too aggressive, you don‘t need the last 5% capacity and use the upper leg of the charge curve. Important they are measured correctly at the cells with correctly well connected sensing wires.
Stop charging at 3,5V or better 3,45V, leave yourself more room for errors plus LifePo4 likes to stay between 30 and 70SOC and not full…
3,65V is 500A relay disconnect all charge sources in HVC (that would be correct)? or disconnect the whole bank= incorrect as you need loads to drive bank asap below 3,65V and therefor shouldn’t shut all off.
Suggest a 3rd 3,75V as Desaster disconnect all. My Electrodacus BMS has separate stop charging, HVC and a fault condition settings, batrium should have them too.
Just my 2 cents…
Happy sailing
Christian
 
Good one. Nuwave also has a 1800W dual burner model that diverts it power needs between the 2burners and doesn‘t exceed 1800W in total….sadly only 120V US…my cat is 230V. Cannot find link at the Moment. Best for a mono as it also fits on top of gimbal stove.
I will look at that. One thing I have noted. When you select the wattage, that is a MAX wattage. The actual wattage is related to the pot/pan. I small pan will not use anywhere near 1800W even if I have 1800W selected. But a big heavy cast iron one will. And if you think about it, that makes sense. The wattage also reduces as it comes to temperature, but that is expected.
 
I will look at that. One thing I have noted. When you select the wattage, that is a MAX wattage. The actual wattage is related to the pot/pan. I small pan will not use anywhere near 1800W even if I have 1800W selected. But a big heavy cast iron one will. And if you think about it, that makes sense. The wattage also reduces as it comes to temperature, but that is expected.
It depends induction stove work differently. They are 3 kinds and You need to measure the actual current used on all settings to figure out how they work. The worst once are always using max wattage and just pulse slower or faster depending on setting, these ones avoid... Mostly the cheap ones.
The next step up are the once that have 2 or 3 levels of the 10 settings eg 800, 1400 and 2000 wattage and inbetween they pulse. Better or great if you find on that performs good. I had 230V Rommelsbacher 3520 with official 3500W both burners but on level 7 were just 2200W and minimal differences to max power and the pulsing made it work on a 1600W multiplus as it was short enough to fit well with peak power, overload warning came partly on but all worked fine.

Best but also expensive ones that actually every setting gradually increase the current and only pulse on each level due to sensing when to keep the heat level. If switch then to temp settings and the current level is different from 1 to 10 settings thats the proof that its commercial grade quality and each burner is really fully regulated.
German Bartscher is one of the Cheapest commercial grade burner and electronic but chassis is plastic, saved money on the right spots as plastic works well/better then in marine. Thats what i have now
 
I will look at that. One thing I have noted. When you select the wattage, that is a MAX wattage. The actual wattage is related to the pot/pan. I small pan will not use anywhere near 1800W even if I have 1800W selected. But a big heavy cast iron one will. And if you think about it, that makes sense. The wattage also reduces as it comes to temperature, but that is expected.
Huh. Good point. I never thought to put the meter on the cooktop to see how much power it's actually drawing. Som
 
Nuwave Pic Gold
Great. Thanks.

I found a demo video on YouTube. Looks like it still cycles a relay to maintain a temp, just with more granularity. I assume it's maintaining a preset temp? Or is it maintaining a preset power level? Perhaps you can set either?
 
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