welded studs

[evad]

Re the welded studs
1-Are all of the studs aluminum ?
2-In a photo showing both the 6mm studs and the 8 mm studs it appeared that the plate for the 8 mm stud was larger then the plate for the 6 mm size. If that is the case it would seem that choosing a cell with a large pad on the cell and a 8 mm stud would be the best configuration to provide a low resistance connection.
3-It would seem that with lower contact area to use a one piece nut and washer and attaching the bms connection other than on the stud would be important.
4-What is the torque allowed on both sizes of studs.

 

[Stepandwolf]

Wow....just found this old question and don't know how it missed getting answered.

All of the studs I have seen are SS. In the examples I have seen, they mold a SS bolt into the aluminum, and then weld the aluminum to the aluminum battery pad. I haven't seen the batteries you are looking at as I have only seen 6mm options, none are 8mm.

Because SS has poor conductivity, it doesn't play a part in the conductivity. You want as much contact as you can get between the buss bar and the battery surface.

I read what the torque spec was but forgot. There is a debate going on whether to get the threaded holes or the studs. The studs being seen only have a 10mm pad area, smaller than the pad area when using the threaded version. Some are putting aluminum washers on the studs to expand the surface area. The other issue is the slotted buss bar reduces surface area vs. using a connector that is drilled for the stud and doesn't have the slot to contend with.