Here's an idea for a way to think about it.
Instead of thinking it in terms of ammo capacity What if energy weapon ammo had a condition? just like other equipment. It continues to supply ammo until the condition is exhausted at no loss of effectiveness.

The ammo display would simply tell you how many shots you have with the cell before it degrades to 0. Based on how much each shot degrades the cell with that weapon and how much condition the weapon has left.
Once a cell is emptied you chance to get to receive and empty cell as normal.

Partial cells are handled just like any other equipment that's degraded. You repair it with another item, In this case an energy cell. Unlike regular repair this would be an unmodified by skills. A 20% cell, a 30% cell and a 15% cell would always be 65% when combined. When you reload you always grab the highest charge available.
It could be taken further and any left over charge say from a 40% cell used on a 70% cell is left behind.

that is basically my idea but without the numbers

and there would still be the clutter issue, with cells of different conditions being separate from one another

that is basically my idea but without the numbers

and there would still be the clutter issue, with cells of different conditions being separate from one another

In fact why not to store those cells internally (inside program) as their respective energy capacity? So your MFC would be stored as 240 but displayed to player like 1.0. It would make calculation of shot energy usage simple as well. Everything would be calculated in "energy" internally but displayed as "cells" to player. You don't have problem with reloading as you are putting "energy" in to your gun. It is just displayed to player as if he is using cells.

Problem solved.

What if they automatically stacked until they, collectivly reached 1 whole cell, then were added to the ammo count, and a new "partial"cell began?

But it sounds simpler and it takes care of the clutter issues by spending 10 seconds in your pip boy. Or as the above basically suggests the recharge is done automatically.

@ Mako - that could work

@ Lord - I get it...hmmm... and i think cell retrieval should be 100% after usage

I keep imagining, time i press F5. that JE Sawyer posts "Wow! I now see how messed up the EW ammo system is! I will have them get to work on this right away!"" or something....

so you would have one MFC but it would count as 240? that makes sense, but there would not be any way to tell how many shots are left in that MFC.. or is it different than what i think it is?

That is beauty of it all: you do not have to know how much is left in "cell". Program stores it as "energy" anyway. It just makes same simple math to display it as "cells" to player: 240 energy = 1 cell so cell = energy / 240.

hmmm, so would it be like my 2nd option, to have MFC renamed to Microfusion Energy? with renaming it would be like gun cartridges, the cartridge being the cell

idk anymore :ahhh:

Exactly. It just would be hidden from player. He will see "cells" where program would be using "energy" (doing simple conversion math when displaying it to player).