shit man… I really hope your ankle is ok.
here is what likely happened
The Low Voltage Cut off (LVC) of S.P.A.C.E Cell is 28v
This is roughly how the LCD is programmed.
42v = 100%
40v = 80%
37v = 50%
35v = 30%
33v = 10%
32v = 0%
Once the battery reaches 0% under load you will probably be hitting the LVC - which means OFF
I am not sure what your readout would have said once it started up the hill & and the motors started drawing more current… but i would assume that your voltage dropped to 0% very quickly. Basically, the LVC of the BMS came on and that makes the board stop accelerating whilst your body continued.
Honestly, I never bothered using the LVC cutoff built into the VESC because I never ride the board uphill with very low battery power. But this is no excuse, I now have to think about all the possibilities that will occur when other people ride.
So from now on I’ll program a soft voltage cut-off at 33V and hard cutoff at 28v, this way if you approach a hill like the one in your video the board won’t shut off rapidly. It will slow down.
Based this video I highly recommend that everyone considers making this change or not riding up hills with low % battery
ALSO, you guys might want to get something like this to help with accessing the USB port on the VESC.
search something like this: "Mini USB Male to Female Right Angle 90 Degree Adapter"