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testing the batteries/cells out of an LG Chem RESU-7H system
That is great news
I found where I saw 63Ah

Later floyd

While charging just before it switched from CC to CV all my packs the cell differential has got down to 1mv-2mv then rose to 5mv as the charge ended.
How's progress going? Have you cycles the packs and done any capacity testing?
I haven't cycled the cells, trying to build fire resistant boxes for capacity testing and charging. The first couple I built weren't to my satisfaction. They will work just not my best work. Also hard to do a capacity test inside (don't feel safe) so outside it is. I couldn't move fast enough if the cells started to go thermal. Easy to toss an 18650 into a bucket of sand not so easy to move a 7s large format lipo battery to bucket.
I will be doing a regenerative discharge as soon as I can. Don't do well in the heat anymore 90f is about my limit and there doesn't seem to be enough hours in the day.

Later floyd
Good point, have you considered using the factory aluminum case? You have two cases? Maybe isolate the once pack being cycled with the remaining good packs in a separate case.

I'm doing mine open air. The only thing near by is the shade sail covering the work area. Worst case, I can't see the nylon rope spreading fire 10ft to the house.

I have been slowly recovering the 7s packs one at a time to 3.0v/cell. Then using the already charged packs in parallel to bring the newest pack up to 4.1v/cell.
Just finished getting the 4th pack to 4.1, the 5th is nearly at 3.0.
That is a thought about using the cases to do the capacity tests, will move one of the cases to the back yard where the other case is. Thank you

later floyd
I cycled my first 7s pack a few times yesterday morning. At 30a charge and discharge the pack was 5 degrees warmer than an unload pack right next to it. So, I think that's a good sign.

I don't have a spec sheet, so I have no idea what I should use for the min/max cell voltage. Any thoughts?

I used 3.5-4.1v
The first cycle was roughly 41ah, third was cut short by the heat (forecast of 110f as you probably know), at 3.6v it had discharged 48ah
I don't know the specs either but that is right around where I was going to use on the discharge test.
I was planning on 4.1v-3.43v (28.7v-24v) not sure what energy is left in the .7 volt from 3.5v to 3.43v but will see what the x8 says. I might end the discharge sooner.
Now I just have to have some cooler weather and free time to discharge test the batteries.
Later floyd
400bird I found this with a search but didn't post it cause I am not 100% sure it is for the right LGX cell
High Capacity 3C / 5C 3.7V 60Ah Polymer Lithium Li Ion Cells combine to 12V 24V 48V 72V 60Ah battery pack


Type : HR37145100300
Material system :Multivariate composite lithium (remark-Multivariate composite cathode material)
Nominal Capacity :60Ah
Minimum Capacity :60Ah
Nominal Voltage :3.7V (Mean Operation Voltage)
Delivery voltage :3.50~3.60V (Within 10 days from Factory)
Charge Voltage :4.20V±0.03V (By standard charge method)
Standard charging method:1.0C constant current,4.20V constant voltage charge to 4.20V,continue charging till current deadline to ≤0.05C (25±3℃)
Standard discharging method :1.0C constant current discharge to 2.75V,
Cell Internal Impedance :≤1.0mΩ (Internal resistance measured at AC 1KHZ after 50% charge )
Weight :0.88±0.02Kg
CC Charge :CC charge 1.0C/60A、cutoff voltage 4.20V,Capacity>60Ah 1.0C
High-Rate Discharge Big GrinC discharge 3.0C/180A、cutoff voltage 3.0V,Capacity>60Ah
Operation Temperature and relative humidity Range:Charge 60±25%R.H.
Discharge 60±25%R.H. -20~60℃
Storage temperature for a long time:-20~25℃≤Six months
-20~45℃≤one month
near the bottom of page there is a cell with lgx XXX couldn't read the last part of it.
Thanks, good find!

I feel like those last two pictures say something like LGY E49 or similar.
And on further reading it appears the units were the RESU 10H as the RESU 7H didn't come with can communications my units' dc-dc converter has a can label, Plus the 6 7s modules 1.6317 KWh x 6= 9.790 kWh is equal to the total power in the RESU 10H

later floyd

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