Grid recharge or car system charge ?

1. So, I own 2 x gen 2 Priuses in Sweden. Over 10 years now. Love them.
   
   But I am attempting my first rebuild on my high mileage gen 2 prius. 320,000km. Battery has been rebuilt before (previous owner, but now 3 modules fail, checked and confirmed via app and then individually out of the car) and as I don't have the right equipment for charge and discharge so I have bought a complete and working Gen 3 pac from a Low mile Prius recently scrapped. I have already disassembled the GEN 3 pac and have the 28 modules still bolted together but away from the harness and case and, sitting on my workshop bench, I check the voltages. They are all sitting nicely around 7,50 to 7,52v as expected with the small dip occurring in the middle cells as expected. I know from previous forum posts not to risk interchange between gen 2 and gen 3 individual modules so i'm swapping the whole block and keeping the "old" block as spares for the other gen 2 I have.
   
   The question is, is this too low a voltage (7,50-7,52 x 28 modules in gen3 pac) to bolt into the car and restart and let the Prius load them up again? Some people talk about mains powered charges as the best options (Jeff) and that the 50W regenerate from the car could damage discharged NiMH but only if its at a low SOC... and im not sure at all the SOC on a 7.51 average volt pac of modules.
   
   #1Yesterday at 4:19 PM
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yes exactly. I bolted out the complete pack of 28 modules to assist in the remounting and now you have advised the the 7.5 isn’t too low I will give it a go and see how she fires up and charges . I’m still thinking of getting the hybrid automotive system though … between myself, my wife and our best friend we have 3 gen 2 priuses that could probably love a little reconditioning..

 

Thanks Dolj. By the way, whats the formula for SoC? PS: Did you know dölja in Swedish is to hide.

 

Most excellent graph. Thank you! I swapped out the rack and plugged it back into the car and it runs like a dream. So no mains charger necessary! Thanks again. Now.... on to an newly discovered air conditioner that will not work....