question

kenamorosano avatar image

Cable length between two lithium battery banks

My 46" Sail Boat has 2 battery compartments due to space limitations. 3 batteries on the starboard side, 2 batteries on the port side where the main DC power grid is based. 4 feet between banks. Batteries are wired in parallel. I understand that Lithium batteries should have equal cable length. Is there a workaround to cable this scenario or is it ok/not ok to wire them this way?

Lithium Batterywiring
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5 Answers
michelg avatar image
michelg answered ·

Hi Kenamorosano, use the same lenght for all the batteries, problem solved. Take the longest as reference.

Michel

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kenamorosano avatar image
kenamorosano answered ·

Hi Michel, that would mean 4-foot cables between each battery. Is that what you mean?

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wkirby avatar image
wkirby answered ·

I'd wire the two banks together in parallel with equal cable lengths for positive and negative. These two cables must be equal length.

Then take the positive from one bank and the negative from the other bank to the DC system. These cables do not need to be equal length.

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kenamorosano avatar image
kenamorosano answered ·

Thanks wkirby. Like this?screen-shot-2022-01-01-at-123302-pm.png


1 comment
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Yes, just like that.
seb71 avatar image
seb71 answered ·

Do you have room to place busbars in the middle? Preferably in a water tight enclosure.

Then connect each battery to the busbars (with fuses on the positive wire). All positive wires same length. All negative wires same length.

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