For RL lasers, I suspect the Blasters from the Star Wars Franchise to be more likely than anything in Fallout.
Good news, the United States Department of Energy has also announce a huge breakthrough in batteries like I think two weeks ago?
I guess it's these.
http://www.theguardian.com/environment/2016/mar/03/us-agency-says-has-beaten-elon-musk-gates-to-holy-grail-battery-storage
http://futurism.com/us-claims-holy-grail-energy-announces-new-battery-storage/
It's for large scale energy storage like the electrical grids for cities, but it has uses for small scale batteries like batteries powering hand held electrical devices, with new chemical and materials that can be developed to be better than lithium ion.
Make what you will of this.
Your first mistake is expecting realism in a game series that isn't even remotely realistic.
It's not simply enough to have a Laser Thread,
One must have several Laser Threads across many information distribution platforms....
No my friends one does not simply say game not remotely unrealistic....
To end this vile evil we must take the One Laser Pistol and submerge it in the fires from wince it came....
No one knows until those things come into existence and are used by the United States military and so on.
Laser gun is just like any other weapon now. If laser guns had no recoil and no sound it would offer a different strategy compared to other guns.
Making laser guns realistic would make the game more strategy based and thus more fun in my opinion.
I think people saw the ShoodyCast video on how unrealistic lasers weapons are and decided to complain.
I'm not sure the United States military would be spending hundreds of millions of dollars (USD) or billions of dollars (USD) in Research and Development (R&D) of laser weapons if laser weapons are unrealistic.
They just need to remove the silly kickback animation and remove recoil on them and the only movement the laser weapon should make is the pull back from you pulling the trigger like in fallout 3 and NV. its current animations look goofy to me. In any game with laser weapons i haven't seen them have any kind of recoil or kickback. Its not about realism its the fact it just looks wrong for a light based beam weapon to have that. Plus at the moment lasers under perform so i think of the recoil is removed it makes them a viable sidegrade.
the recoil on laser weapons is unacceptable, final words.
I don't care about twisting reality, but going against it, no.
Is there a dual-wielding mod?
I mean, truly dynamic dual-wielding, like a .44 in one hand and a Sawn-off Shotgun in the other? Not just "TWO GUNS!?" which are identical.
Edit : On topic, I want blue lasers. In fact, RAINBOW lasers! I'd actually use them then!
But a lot of things in Fallout go against reality. You might as well just not play the series if going against reality is unacceptable. As someone said Fallout is base off 1950s sci fi.
Almost every game and science fiction story gets laser weaponry wrong. Not because of not understanding how laser weaponry would work, but because laser weapons are boring. When you fire a rifle, you get the recoil, noise, and watching the bullet rip through the target in all its bloody gore. With the laser weapon, there is no recoil or noise and the laser will likely cauterize any wound that it makes. All we would see is a dot on the target before it is destroyed. A powerful enough laser should be able to ionize the atmosphere so there is some visual effect and maybe getting some type of sound from the ripping the electrons off of the air molecules, but that is just wasting resources to make laser weapons look cool. In space, it is even worse since there is no atmosphere to ionize and the distances involved are usually far longer. So a ship would fire their laser at where they expect the enemy will be in two seconds, then wait 4 seconds to determine if they actually hit the target or not. Consider how easy it is to miss a shot in space, it wouldn't surprise me if laser weaponry in space will be laser shotguns instead of focused laser beams. After all, try to hit a moving target that is about 200 meters big and 300,000 km away. Shows like Star Trek and Star Wars wouldn't be as exciting if they took a more realistic approach.
In one show that I watched, a character in the show mentioned that the visual effects and sounds were edited into battle footage to improve the ratings.