If you want to win this battle, we recommend fighting as Diluc or Ganyu, who can do a lot of damage to this boss.
As the confrontation begins, Baal will step back and begin charging. He will start pushing everything and everyone with the help of some purple circles. Given this you will have to avoid these attacks and avoid damage. Make sure to stay away and use ranged attacks.
When you manage to reduce at least a quarter of Baal's health, the second phase of the encounter begins and here you will have to deal with a frenzy in which you will find yourself behind. what you have to do is keep attacking until you see the scene that marks the end of the encounter.
Now that you know how to beat Baal / Raiden Shogun in Genshin Impact, you are ready to deal with this boss and take him out without any problem.