The EIG NMC cells in the for sale section (sorry I forget whose thread it is) would do that; they're 5C continuous cells (10C for 10sec), so a 20Ah pack could do 100A continuous. I don't know the history on what's in that thread, but I'd bet at least most of the cells are good (you'd have to talk to the seller).
I use these on my bike and trike; all of what I got was used already, and still works fine (have had one cell of all the ones I've used degrade significantly, and one in my lighting pack died from overdischarge so far I reversed it--but the other three that were in series with it still work--and they'd already been abused to just about zero once before and recovered).
The ones in teh for sale section are nice and modular, bolt together packs, I think what he's got are 2P packs (40Ah) but you could make different busbars that make them 1p (20Ah) packs, at whatever series number gives you the voltage you need.
They're 4.15v max cells (I use 4.1v max on the lighting pack, and 4v max for the trike's traction pack for typical charge, and 4.14v for "full" charge). I'm using 14s, and a 2p pack weighs around 35-ish lbs. So a 1p 21s pack (87.1v full @ 4.15v/cell) would be about 26-27lbs bare.
You could go 22s and only charge to 4v/cell to lengthen their lifespan, for an 88v full pack.