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The most convenient place for me to put the shunt resistor for checking current in my system is between the two halves of the battery pack. I have 8 modules total, each 1 kwh 4s3p modules. The shunt resistor is one of the typical 500a / 50mv types.

Question is: would I expect to see 100% of the current at this point or just half?
 

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It's always a good idea to put the current shunt on the most negative terminal of the battery. Because you are aiming to measure a voltage drop across the shunt, it needs to be referenced to 0 V, and that can only happen at the battery negative.

An isolated voltage measurement is possible, but if you plan on using a Coulomb counter for measuring state of charge, it will also need to measure voltage, and for that it expects to measure a potential between pack (+) and pack (-).
 

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You would see 100% of the current (the current is the same in each component of a series string), but for example, the voltages across the shunt will be 64.01 to 64.00 for 100A thru the pack.

It would require an isolation op amplifier or other countermeasures to read that 10mV on top of the 64 V at mid pack.

That is why jones recommended to put the shunt at the bottom of the pack, it's easier to read 10 mV above ground, than 10 mV at 64 V above ground.
 

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Thanks for the advice everyone!

I hadn't considered the voltage difference thing. I have a Raspberry Pi that is monitoring the voltage but it would be at chassis ground. Now I need to figure something else out...
 
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