How do I recharge my photon cannon in my ship?

My ship has a photon cannon which currently has 0% energy. I get a pop up in the bottom right saying to recharge my my photon cannon with oxides, but in the ship inventory, there doesn't seem to be an option to recharge the cannon.

The cannon still fires even though it's at 0%. This leads me to believe that there's some sort of design flaw here in the game.

Am I missing something or is this a flaw as I suspected?

Note that this is separate than the beam weapon. That has its own charge, which I can recharge no problem.

You're experiencing a glitch. I know this from personal experience - it does it to me also, and from research. This happens in one go - one second you're at 100% and the next at 0%.

The cause of the glitch is unknown, but some sources suspect it may be due to fully depleting your phase beam then switching to your cannon.

However, what I do know is this - while it may continuously ask you to recharge with oxides, the bug doesn't do anything, so it is safe to continue your normal mining operations, without any repercussions. And here's a PC "fix", involving cheat engine.

Yes, this is a flaw in the game.

EDIT: The overheat bar is separate, and the "charge" of most weapons is shown in the top right, next to the overheat bar, as "N%". This issue also makes a tooltip appear in the bottom right, asking you to recharge your cannon with oxides. This is one of the leading causes of the suspicions above. Another thought is that it may be due to buying a new ship that has the photon cannon pre-charged at that percentage - usually 0.

EDIT 2: Also, due to the bug, you lose the "lead" bug while combating enemies in space, making it much more difficult to aim at pirates with your cannon. This is most likely, due to this more major repercussion, going to probably be fixed in the next patch.

The Photon Cannon does not need any recharge, it is a weapon that has been given to you from the start of having your very first ship and is automatically a part of every ship you purchase afterwards... It over heats but does not need any recharge.