Supermate and Transformer

Some questions about good and bad batteries:

1. I've heard that a final discharge of 6A is a good module. I'm averaging around 5.6A for each module. Is that acceptable?

2. The final discharge is somewhat relative to the amount of current that is put into it. Said differently, setting a charge limit of 7.3A will yield a higher discharge current than using a 7A charge limit. Is the standard 7.25A?

3. If a battery holds greater than 70% of the charge current when discharging down to 6V, is that considered a good battery?

 

Mine measured at 6.5+A after the third cycle, but 6 isn't bad as long as they are all about the same capacity.

Yes, a lesser charging will result in a lower capacity reading. The reason to limit the charging is to protect the higher SOC cells from over heating during the process.

As I said above, the important measure is the balance between the 28 modules, not the specific capacity. Bob Wilson did measurements on his Gen1 as the battery aged and at 50% capacity remaining, he still saw the same MPG performance as when he replaced the battery with a full capacity one from ReInVolt.

JeffD

 

Thanks for the information, Jeff.

Are his findings on the internet somewhere? How did he measure 50% capacity? Just like the way I did, where you charge the battery, discharge it and the take the percentage of charge current to discharge current? It's surprising to see that he was getting ~3.6A and his MPG's weren't affected. My batteries aren't so great due to the 5.6A discharge from full charge to 6V.

Is this a true statement? The true indication of a healthy battery is relative to the remaining capacity but as far as the Prius goes, at least in this specific case, the more important consideration are the voltage readings between cells.

When I took measurements of my batteries before I started rebalancing they were all 7.63, except one, which was 7.4.

 

The module at 7.4 was subject to a cell reversal if you ran the battery SOC down to 1 or 2 bars.

ReInVolt PHEV Plan | PriusChat is a thread where Bob discusses his early experiments.

JeffD