Best cell for a yacht

[Isabella Blue]

Hi battery gurus,
I have been researching replacing the 320Ah SLA’s with LiFePO4 on my sailing boat for a long long time! Why - because an off the shelf battery will not fit the defined space and I have almost given up on trying to purchase individual cells based on people getting ripped off by shady suppliers with no guarantee you will receive the new cells to the specification (endless bad reviews).
I am almost at the point of buying two SLA’s - easy straight forward transaction from one of a thousand reputable suppliers, unfortunately the same cannot be said of LiFeP04!
So - I come to this forum asking for guidance re the purchase of LiFeP04 cells from a reputable manufacturer/supplier. I am looking at a 400Ah system using a combination of cells to fit the defined space and I have narrowed the cells down to Lishen, Winston or EVE. Are any of the cells better for the intended application - installation on a sailing vessel? Who is a reputable supplier?
Any assistance is greatly appreciated.

 

[Browneye]

All of those cell brands are good, and there are a few reliable sources for them. You can buy them from an importer, shipped from a US warehouse, or order direct or from a china distributor. One ships faster and is more reliable, the other you wait and take your chances.

If you're going to build a DIY system you're going to test out all your cells before putting them into regular use anyway, so no worries. There's a lot of bad press but plenty of good ratings too.

Lots of us have bought cells from the Docan warehouse in Houston, where I got mine for my RV, you can contact Amy Zheng from this thread:

Good review on supplier.

I purchased 4 280 catl from @Amy Zheng from power wholesale, All of my contact with her was done through Facebook messaging. I purchased from usa warehouse and received them in 3 days. The packaging was excellent, packed 2 per box. Batteries arrived with no damage and no bloating. Voltage...

diysolarforum.com

There's a link to their online store that shows what they have in the US and what they have coming from China.

While the cells are the main part of a system, there's an awful lot of ancillary bits that go into making a full system. This site is a big help with spec'ing and sourcing all that. Lots of happy DIY'rs.

 

[Goboatingnow]

Before you do anything contact your insurer , many have significant policy restrictions if Li batteries are installed especially anything DIY.

 

[Browneye]

Lifepo4 batteries are not inherently more dangerous than flooded lead acid. It's all in the design and installation - nothing exclusive to chemical make up.
LFP gives you double the capacity for a third the weight and half the size. They just go and go and go, like the energizer bunny.

I've been working with 12V systems in boats and RV's for over forty years, and these new systems are nothing short of amazing.

 

[Isabella Blue]

All of those cell brands are good, and there are a few reliable sources for them. You can buy them from an importer, shipped from a US warehouse, or order direct or from a china distributor. One ships faster and is more reliable, the other you wait and take your chances.

If you're going to build a DIY system you're going to test out all your cells before putting them into regular use anyway, so no worries. There's a lot of bad press but plenty of good ratings too.

Lots of us have bought cells from the Docan warehouse in Houston, where I got mine for my RV, you can contact Amy Zheng from this thread:

Good review on supplier.

I purchased 4 280 catl from @Amy Zheng from power wholesale, All of my contact with her was done through Facebook messaging. I purchased from usa warehouse and received them in 3 days. The packaging was excellent, packed 2 per box. Batteries arrived with no damage and no bloating. Voltage...

diysolarforum.com

There's a link to their online store that shows what they have in the US and what they have coming from China.

While the cells are the main part of a system, there's an awful lot of ancillary bits that go into making a full system. This site is a big help with spec'ing and sourcing all that. Lots of happy DIY'rs.

Thanks for the information and vote of confidence. As you mentioned cells are one part of the system the other main part is a suitable BMS for my application. I have an all Victron Energy system that includes a 3000W multiplus inverter/charger, 30A MPPT, battery monitor, Cerbo GX and touch display. At this stage I have narrowed down to two options 1. REC with CAN comms to integrate with the Victron, 2. X2 BMS. I like the option of external contactors to isolate the load and charge bus.

 

[Isabella Blue]

Before you do anything contact your insurer , many have significant policy restrictions if Li batteries are installed especially anything DIY.

Thanks for the heads up. I checked this at the beginning of the Li journey as a sailing colleague mentioned the same thing. My insurer has no issues with Li batteries and I am an electrician by trade so no issues with the DIY side of things.

 

[Warpspeed]

I would definitely go Lithium, no acid, no fumes, no requirement for topping up, less weight and smaller size.

The different brands and cell physical sizes available give you quite a few different alternatives to stacking various sized cells in various combinations.
Its a fair bit of work nailing down all the cell packing alternatives possible, as there are no standard recognized cell dimensions between manufacturers, but its well worth exploring all the alternatives.

In a boat, it may be just about impossible to prevent some slight physical movement of individual cells.
Definitely not a good idea to use the solid busbar links supplied by the battery manufacturer.
Much less stress on the terminal posts to use lugs and fine stranded flexible cable to link up between individual cells.

 

[brendanisatsea]

Thanks for the information and vote of confidence. As you mentioned cells are one part of the system the other main part is a suitable BMS for my application. I have an all Victron Energy system that includes a 3000W multiplus inverter/charger, 30A MPPT, battery monitor, Cerbo GX and touch display. At this stage I have narrowed down to two options 1. REC with CAN comms to integrate with the Victron, 2. X2 BMS. I like the option of external contactors to isolate the load and charge bus.

Hi Isabella! I'm really curious to know where you landed in the X2 VS REC decision? I've been looking at a very similar application on my Cape George sailboat and have been stuck between REC, X2 and Tao - This said, I'm leaning towards X2 because of their extra safety systems.
Have you finished your project yet?

 

[Isabella Blue]

I have just ordered 8 x LF280K cells direct from EVE. Lead time is 3 months so plenty of time to decide on series/parallel connections and BMS. Whichever one I choose I will follow the KISS principle, one contactor will isolate the batteries from the load and chargers - the alternative, separation of charge and load bus with multiple contactors is too complex and too expensive.

If overvoltage open circuit, if undervoltage open circuit - this is the same principle as a manufactured lithium battery with internal BMS - any comments?

 

[Goboatingnow]

I have just ordered 8 x LF280K cells direct from EVE. Lead time is 3 months so plenty of time to decide on series/parallel connections and BMS. Whichever one I choose I will follow the KISS principle, one contactor will isolate the batteries from the load and chargers - the alternative, separation of charge and load bus with multiple contactors is too complex and too expensive.

If overvoltage open circuit, if undervoltage open circuit - this is the same principle as a manufactured lithium battery with internal BMS - any comments?

* correct , One "fail safe " not latching contactor which the BMS will trigger on any safety event , over voltage , under voltage , over current , or outside temperature limits . after disconnect NOTHING should remain connected to the battery except the BMS. This makes the system ISO or ABYC compliant which will be a big factor in insurance consideration

* ensure that after a safety disconnect , do not have any charge sources automatically reconnect without manual intervention

* ensure you have manual workarounds to reenable the battery if in extremis you must have dc power back

* make sure you treat the safety disconnect as just that, an event that indicates a fault and must be investigated , charging should stop before HVC and loads should disconnect above LVC , hence a smart battery saver is useful to add to cut loads before LVC occurs ( or use the Cerbo etc )

have a safe and impressive battery , note however a DIY install on a yacht , will most certainly have insurance implications. Talk to your insurers to see what their policy is

 

[Warpspeed]

The above is excellent advise.
The safest control strategy is to totally isolate the battery in the event of either overcurrent, or the voltage going beyond safe limits.

The simplest and most acceptable way is probably a dc rated circuit breaker fitted with a shunt trip coil.
The circuit breaker itself will trip on overcurrent, and will need to be manually reset in the usual way.

The shunt trip is an alternative way of mechanically tripping the breaker if the battery management system decides that the battery voltage is becoming either dangerously high, or dangerously low. Once the breaker has tripped it can only be reset manually.

If you really want to be certain, fit a suitably rated fuse in series with the circuit breaker as well.
Circuit breakers have been known to weld themselves together.
And carry some spare fuses!

 

[Goboatingnow]

I would not recommend the breaker as described. You have to have an advancing alarm capable BMS in the system , so this can manage a contactor for all safety trips. I would agree last ditch fuses should also be present.

 

[Isabella Blue]

My journey is almost complete.
The installation is finished and I am testing the system and charging devices to ensure they are communicating and playing well together - so far so good.
I have noticed the REC SOC differs from the Victron BMV, 10% at the moment. As they use the same shunt i assume it is one of the BMV configuration parameters. Has anyone had experience with this issue and found a fix?