While it may be fun to write a paper that attempts to analyze the feasibility of using antimatter for energy storage, in real life this does not have any chances to be done, except in a very distant future, like at least a century or more likely several centuries from now.

The energetic efficiency of producing antimatter in order to store energy in it is well approximated by zero.

Storing antimatter requires a huge volume and mass per the energy stored and it also requires a continuous power consumption, so long term storage would degrade the energetic efficiency even more.

There are methods of producing energy that nobody knows how they could be done, like nuclear fusion without producing neutrons (aneutronic fusion), but which nonetheless have a chance to be realized that is much, much greater than discovering a method of producing antimatter with high efficiency and also solving the problems of long term storage and of harnessing the energy produced by annihilation as intense destructive radiation.

For now, the only realistic research target for improving space propulsion in the next few decades is the use of nuclear fission reactors, which could allow travel inside the Solar System with much more acceptable durations.

If you could figure out production and storage of antimatter, space travel would be very different.

I remember reading a Robert L Forward book where he described all this in great detail.

EDIT: I think the book was "Indistinguishable from Magic" which was interesting science-wise but not compelling as a science fiction book.

He also seems to have written about antimatter directly: "Mirror Matter: Pioneering Antimatter Physics"