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Parallel connection vs dual connection

Yurtdweller

Solar Enthusiast
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Nov 23, 2020
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273
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USA
I have a simple question, I think. I just need to ask it. I am preparing to wire two separate 12v 280ah LiFePo4 packs together for 12v service. Of course, the recommended method is parallel, with POS on one pack and NEG on the other, and leads going to pos and neg load buss bars.
My question. My load terminals are very close to the batteries. Is there a reason to not attach leads to each battery pos and neg, and then connect those leads to the load busses?
I'm guessing that the two batteries act as a more cohesive unit if they are wired in parallel? Just curious. Thanks.
 
I have a simple question, I think. I just need to ask it. I am preparing to wire two separate 12v 280ah LiFePo4 packs together for 12v service. Of course, the recommended method is parallel, with POS on one pack and NEG on the other, and leads going to pos and neg load buss bars.
My question. My load terminals are very close to the batteries. Is there a reason to not attach leads to each battery pos and neg, and then connect those leads to the load busses?
I'm guessing that the two batteries act as a more cohesive unit if they are wired in parallel? Just curious. Thanks.
If I am following your question, you are suggesting something like this:

1642018036551.png

This is a good way to do it as long as the wires from the negative busbar to the batteries are all identical and the wires from the positive busbar to the batteries are identical.

However, for only 2 batteries I like the 'diagonal' better.

1642018080461.png
Notice that fewer cables need to be made identical.

The reality is that as long as you are careful with building the cables, either method will work fine... but I like to minimize the opportunities for me to screw something up.


Note: For 3 or more batteries, I prefer your method. (The diagonal method is well balanced for 2 batteries but less balanced for each additional battery)
 
Last edited:
Ok. You read my question correctly, and confirmed my suspicions. I also see the need for matched cables. I build my own, and wanted to ask before I start cutting and crimping. If there is no particular advantage either way, I will most likely follow the established norm for parallel wiring for simplicity. It just seems like having each pack on it's own leads might result in better charging, individually, but perhaps traditional parallel wiring will result in a more balanced set of packs? And since one cannot draw more than the lowest pack, I don't suppose there's any advantage to having them seperate. Thanks.
 
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