Why to buy a high performance battery?

A few weeks ago, my Cadillac battery had to be
jumped to start, after that it ran pretty good. Once I
turned it off it wouldn’t start again. Someone told
me it needed a new battery, but there isn’t a lot of
places that sell high performance batteries and it
has to be ordered with a deposit. Still haven’t found
a auto place that sells high performance batteries
and I am left with looking at my truck in the
driveway. Having a electric truck gives you many
unresolved problems. Does anyone have any
suggestions?