Four years ago I bulit a Jr Dragster for Grandson. I used Milwaukee M28 tool batteries. Two packs of six in parallel. The two packs are in series for a total of 56V to controller. This ran consistent for 4 years.
I want to step up to next class and am looking at Milwaukee M18 9ah batteries. 6 batteries in series will give 108 Volts. I am thinking of 2 or 3 packs in parallel.
My question is is it feasible to put 6 tool packs in series?
I don’t know why not. Seems an expensive way to buy batteries. Do you have a bunch around?
Actually the first car was sponsored so I hope to get sponsor to buy these batteries.
This concept makes it easy and simple. The use of the battery packs eliminates a BMS system and with multiple batteries can always have freshly charged batteries. Just unplug and snap in fresh batteries. The turn around time at local track is very short.
I’ve thought of doing the same thing. 
Cost got in the way.
HEY!
How about a picture or 2 and more info on what your talking about?
Rodney