A fully charged, healthy battery MUST be in circuit as it presents a ballast/load/resistance to the flow of current.
Uber-high voltage is the order of the day w/o a proper battery present.
As an imbittered old mechanic i fully expect bad news about these light weight Shorai batteries.
Turn the clock back several years...
Remember the cell phone batteries that were blowing-up in ppls pockets?
Yep. There were metal fines in the gel causing cells to dead short = BANG!
The Shorai accepts charge very fast and that generates heat. i think it does not offer the proper ballast for M/C or car use. These types of batteries are TITS for RC aeroplanes however.
Just my $0.02