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Discussion Starter · #1 ·
This is the area that I am weakest. I am at a point where I need to test the individual modules from my salvaged 2013 Nissan leaf pack.
1) What do you use to test individual modules? (Have a multimeter in which I can get the static voltage).
2) What do you use to charge individual Modules for testing purpose? DC power supply?

Would this DC Power supply work?

Product Automotive lighting Font Output device Line
Product Automotive lighting Font Output device Line
 

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This is the area that I am weakest. I am at a point where I need to test the individual modules from my salvaged 2013 Nissan leaf pack.
1) What do you use to test individual modules? (Have a multimeter in which I can get the static voltage).
2) What do you use to charge individual Modules for testing purpose? DC power supply?
192.168.100.1 192.168.1.1
so you want to convert the engine to an electric one
 

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You should utilize the gear made for the RC market. That power supply is 5A max, which means to charge up a 66Ah module from nearly depleted it will take half a day, and you have a bunch of them. And then what do you mean test ? You're definitely not testing much with your multimeter, you will need a load tester / coulomb meter.
 

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Discussion Starter · #4 ·
You should utilize the gear made for the RC market. That power supply is 5A max, which means to charge up a 66Ah module from nearly depleted it will take half a day, and you have a bunch of them. And then what do you mean test ? You're definitely not testing much with your multimeter, you will need a load tester / coulomb meter.
This is why I am asking the question? I understand that using a mulitmeter will only take a static measurement. Soooooooooo educate me. How would you test the modules. Would you charge the module and see how much it charges... or would you get a Dynamic tester (Which one, what band). What charger would you use? What band do you use?
 

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I'd charge them all in parallel, up to, I dunno, I guess 4.2v if you want to test them fully. I'd use... hmm, probably something like a few surplus server power supplies or old PC PSUs with the 5v rails ganged together. It'll take forever, so, keep an eye on them, touch them ones in a while to test for heat, and manually disconnect the power before they rise above 4.2v. Maybe use a stove/oven/dryer element to limit the current to something the PSUs can handle without crapping their pants. Or if you like spending money, I dunno, maybe this for $100: 15 Volt Variable Output Switching DC Power Supply 25 Amps . 3-15v, up to 25A.

Then I'd string them all up in series, and discharge them across, I dunno, a few junkyard oven elements or a water heater element (perhaps in a convenient water tank). Enough so that it takes probably, oh, an hour or 2. That'll roughly mimic driving. While discharging, every few minutes I'd be hopping cell to cell, testing the voltages and seeing if any of them are suspiciously lower than their peers. If you start to see serious differences in some cells, I'd stop the test and yank the bad ones out and then continue. Honestly, since you'll be doing like, 100, it'll probably be like painting the Golden Gate Bridge. As soon as you finish painting all the way to the far end, it's time to start over at the beginning again.

Should be able to do it on a Saturday for nearly zero budget.

You don't really need to test them under load like you would with lead acids. Symptoms will be a refusal to rise in voltage, a quick drop in voltage, or obviously excessive heat at any point in the process.
 

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Discussion Starter · #6 ·
I'd charge them all in parallel, up to, I dunno, I guess 4.2v if you want to test them fully. I'd use... hmm, probably something like a few surplus server power supplies or old PC PSUs with the 5v rails ganged together. It'll take forever, so, keep an eye on them, touch them ones in a while to test for heat, and manually disconnect the power before they rise above 4.2v. Maybe use a stove/oven/dryer element to limit the current to something the PSUs can handle without crapping their pants. Or if you like spending money, I dunno, maybe this for $100: 15 Volt Variable Output Switching DC Power Supply 25 Amps . 3-15v, up to 25A.

Then I'd string them all up in series, and discharge them across, I dunno, a few junkyard oven elements or a water heater element (perhaps in a convenient water tank). Enough so that it takes probably, oh, an hour or 2. That'll roughly mimic driving. While discharging, every few minutes I'd be hopping cell to cell, testing the voltages and seeing if any of them are suspiciously lower than their peers. If you start to see serious differences in some cells, I'd stop the test and yank the bad ones out and then continue. Honestly, since you'll be doing like, 100, it'll probably be like painting the Golden Gate Bridge. As soon as you finish painting all the way to the far end, it's time to start over at the beginning again.

Should be able to do it on a Saturday for nearly zero budget.

You don't really need to test them under load like you would with lead acids. Symptoms will be a refusal to rise in voltage, a quick drop in voltage, or obviously excessive heat at any point in the process.
Thank you for your reply I will check this out.
 

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I would measure the internal resistance of the cells to see if any are out of whack comparatively. Also if you are paralleling LEAF modules for a lower voltage then you want to pair modules based on internal resistance; pairs should be as close to identical internal resistance as possible.
 

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Discussion Starter · #8 ·
I would measure the internal resistance of the cells to see if any are out of whack comparatively. Also if you are paralleling LEAF modules for a lower voltage then you want to pair modules based on internal resistance; pairs should be as close to identical internal resistance as possible.
Okay: I will be breaking the pack probably next week. I took a screen shot of the leaf spy so i kinda know which modules as better then others.

Thanks for this advise.
 

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If I'm not mistaken, the Leaf cells (AESC) are dual 2s2p modules. 7.2V nominal.
The central terminal is only for the BMS connection (not for power), do not connect a charger to it: the internal wire may have a small section.
 
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