Electrical feedthroughs are presented that are integrated within a wall of a battery housing. In some embodiments, an electrical feedthrough includes a battery housing defining an opening. The electrical feedthrough also includes a collar disposed around the opening and forming a single body with the wall. The electrical feedthrough also includes an electrically-conductive terminal disposed through the collar. The electrical feedthrough additionally includes an electrically-insulating material disposed between the collar and the electrically-conductive terminal and forming a seal therebetween. In some embodiments, the wall has a thickness equal to or less than 1 mm. In some embodiments, the collar protrudes into the battery housing. In other embodiments, the collar protrudes out of the battery housing. In some embodiments, a cross-sectional area of the electrically-conductive terminal is at least 40% of an area bounded by an outer perimeter of the collar. Batteries incorporating the electrical feedthroughs are also presented.