Sourcing and build LFP bank for marine application.

[Philipay]

Hello guys, I would like to share my LFP build (on going) staring from buying the LFP raw cell to build a battery bank for my boat's house battery.

Here is my story, Im planning to do a blue water voyage with my 42ft sailboat. The conventional AGM battery wont last long enough for my equipment's power concumption in case of any engine or power generator failures. The previous house battery consist of 6 -115ah parallel which provide up to 690ah. Im planning to work on a full upgrade to LFP with the newest EVE 314 ah (MB31) and the new build is gonna be 4S 4P which will be total of 1256ah for my 12v system.

1. Buying raw cells from wholeseller.
Staring from the battery sourcing I did a lot of research and seem EVE is one of the top brand in LFP and they are one of the brand that selling 314ah to the consumer market with 8000 cycles. I read and heard a lot of stories regarding those raw battery bank are refurbish from old vehicles, repackage and put a new lable on it, or those cells are poor quaility that sell to the market and reserve the best quality batch for big EV companies. So I pay extra caution when buying LFP. Giving my geography advantage, I found a battery wholeseller and I visit them in person to purchase the raw cells.




I picked the battery on my own just like picking fruit from the supermarket, and they help me to laser weld the battery stud on-site.

2. Buying the BMS
I picked Daly for the BMS system, they used to have a parallel BMS for battery storage, it is the older model and I know they have a new BMS call Daly 100 (blue lable) which build in 1A active balancing, buildin bluetooth. I just bough 4 sets with a Nov11 discount and waiting for them to come!.

 

[packrat1969]

Hello,
I would be interested in observing the progress of your house battery build. You said 4S4P, so that means (4) 314Ah 12V batteries parallel, right? Each with its own 100A BMS? What is your expected maximum current draw? (4) 100A BMS units in parallel will give you a lot of amps, but what plans do you have if one or more BMSes fail? Also, even if you get new and good quality cells, is 1A of balancing on 314Ah going to be enough to balance things in a timely manner. Is there more engineering and planning going on that you have yet to tell us?

packrat

 

[HRTKD]

2. Buying the BMS
I picked Daly for the BMS system, they used to have a parallel BMS for battery storage, it is the older model and I know they have a new BMS call Daly 100 (blue lable) which build in 1A active balancing, buildin bluetooth. I just bough 4 sets with a Nov11 discount and waiting for them to come!.

If I was in a situation where I was relying on the battery bank, I sure as hell wouldn't be putting a BMS from Daly on my batteries.

 

[Ohms_Cousin]

Hello,
I would be interested in observing the progress of your house battery build. You said 4S4P, so that means (4) 314Ah 12V batteries parallel, right? Each with its own 100A BMS? What is your expected maximum current draw? (4) 100A BMS units in parallel will give you a lot of amps, but what plans do you have if one or more BMSes fail? Also, even if you get new and good quality cells, is 1A of balancing on 314Ah going to be enough to balance things in a timely manner. Is there more engineering and planning going on that you have yet to tell us?

packrat

Good questions Packrat - I am wondering the same things that you have asked. I hope the OP comes back and fills the thread out in some detail.

 

[Brucey]

If I was in a situation where I was relying on the battery bank, I sure as hell wouldn't be putting a BMS from Daly on my batteries.

At the very least maybe a couple spare units for inevitable failure mid ocean.