How should I configure 16 LiFePO4 cells in series for 48V in tight space?

Lily

New Member
I have a tiny cruise capable sailboat converted from diesel to electric motor Motoenergy ME0201013601, max consumption 2500W at 48V. I am moving the batteries to a deep rear storage compartment accessible from both an overhead water tight hatch and a quarter berth. Very difficult but doable. Today's question - how best to configure the pack? Is it ok to stack 2 groups of 8 on their sides with tops facing forward? Or would it be better to keep them vertical like attachment From the top? Is From the Top wired correctly?
 

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Ampster

Renewable Energy Hobbyist
Back in the day when I spent more time on the water knocking about on sailboats we always tried to keep the heavy stuff low and as close to the keel as possible. Weight in the ends makes for a lot of extra motion.

Stacking them on there sides is what I am going to do in my garage. I am more worried about earthquakes now so I will strap or clamp them as should you.
 

Lily

New Member
I'm jealous!
Stacking on their sides should not be problematic
Thank you. Two banks of 8 cells stacked on their sides makes the wiring simpler. And I already have end plates and bars to hold them together. I had them that way originally but they didn't fit in the deep locker sitting upright. I didn't consider just tipping them over one on the other:rolleyes:
 

Lily

New Member
Back in the day when I spent more time on the water knocking about on sailboats we always tried to keep the heavy stuff low and as close to the keel as possible. Weight in the ends makes for a lot of extra motion.

Stacking them on there sides is what I am going to do in my garage. I am more worried about earthquakes now so I will strap or clamp them as should you.

Agreed. Unfortunately the space between the top of my keel and cabin floor is about 4 inches; ditto for under the settees. I'll post a picture when I get them set up.
 

keimor85

New Member
Battery Pack & BMS.png Here's how I plan to configure my 48V 200Ah pack and BMS. The dimensions do not include the battery pack enclosure.
 

Ampster

Renewable Energy Hobbyist
If you want the interconnect at the top to be shorter, you could start the top left hand column so the positive terminal on the top is closer to the negative just to the right of it.
 

keimor85

New Member
If you want the interconnect at the top to be shorter, you could start the top left hand column so the positive terminal on the top is closer to the negative just to the right of it.
I tried that at first but I was worried that the two terminal (+ & -) going to the BMS were to close together. I'll see how close they are in actuality when the batteries arrive. I also thought that I could do it this way and put an insulator between them, maybe a piece of G-10 or FR-4.
Screen Shot 2021-02-22 at 9.15.49 AM.png
 

Ampster

Renewable Energy Hobbyist
Even though my BMS compenates for the extra resistance of different length interconnects I wanted to reduce that. In my 2P16S pack my negative and positive are close together with no issues. It is more personal preference.
 
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