I don’t think I’ve had a pacman update take longer than 10 minutes before. Sounds like OP was updating all their AUR packages too.
Still absolutely a terrible thing to do on 10% battery life. I bet there’s an AUR package for “check battery level before update” out there somewhere though.
OPs meme is "use distro whose model is ‘give users enough rope to hang themselves’ " and complaining he’s at the gallows