Common ground for several batteries.

Thread Starter

crchisholm

Joined Jun 28, 2012
1
I 3D printed a box to hold about 50 AA batteries. All the battery negative poles touch the bottom of the PLA box. i wonder if it would be a bad idea to place a metal plate at the bottom of the box so that the batteries are all grounded tho the plate. The box offers access to the positive pole of the batteries so I could quickly check the voltage of batteries and discard those that have fallen below a certain voltage (say 1v). Seems like this would not be an issue but after i got myself into trouble about “ground loops” a while back, might be better to get guidance.
 

dl324

Joined Mar 30, 2015
16,788
Welcome to AAC!

I doubt that ground loops would be much an issue, but getting a good contact to the negative terminal might.
 

crutschow

Joined Mar 14, 2008
34,201
Seems like this would not be an issue but after i got myself into trouble about “ground loops” a while back, might be better to get guidance.
"Ground loops" are generally only a problem in small signal AC circuits.
There's no problem with connecting all the negative battery terminals together.

But as dl324 noted, there could be a problem making good contact to the flat negative battery terminal unless there was a raised contact for each battery.
Might work better to store the batteries with the plus terminal down, as that likely would make a better contact, especially since you would be pushing down on the battery when measuring it with a probe.
 
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