Your battery was down to 48V when it shut down. I call that a noticeable drop if it started fulled charged around 54V and all it has to do is spin the motor with no load. Your earlier data does not show any of the cell groups to be off on voltage. All I would say is that maybe the battery is tired out.
You can, if you wish, look at LVC on that LCD3 display. It will will the C12 setting. If it was set too low, like at 0 which lowers LVC to 40V, that would have been harder on the battery.
Last edited by Doc_Wui; 08-02-18 at 06:54 AM.