bad Dewalt QC or what is normal and what isn't

[kbarrett]

Ok, I've opened the rest of Dewalt packs - I've got another bad pack with a cell at 0.6V. I start to wonder if there is some sort of factory sealed B-stock or they were stored for too long. This is a bit frustrating, I need to order two more packs (or one if I mess with the welded tabs and try to replace a single cell).

Do yourself a favor ... bite the bullet and break them up completely. Parallel them up 6 across, and use as many 3.3v 6 cell packs as you need to get the voltage you want.

More work in the short term, yes ... but those 10 cell series 33v packs are going to be a bear to keep balanced.

Besides, if you go that route, you can use goodrun's LVC and the BMS he and Don are cooking up.

 

[curious]

I do indeed connect each cell in parallel across packs while using welded tabs for serial connection - you can check pictures in my build thread in this forum. LVC is a must but I may do my own design (have not decided yet on that). But LVC will be external to the pack. As for the charger - I am in the process of designing my own fast charger.