My 2 cents:
First all, exoskeletons in their current form is basically a weight bearing aid. It allows a human to carry more weight than otherwise allowed. HOWEVER, there are severe issues in using these by combat patrol troops.
Troops are trained to drop their "luggage" when encountering enemy. They need to run, jump, climb, crawl and fall down to find cover and to manoeuvre into firing positions. The exoskeletons of todays form only function correctly within very limited mode of movement, e.g. standing up, walking or running slowly. They hinder rapid movements required during a combat situation. Try ask a solider wearing an exoskeleton complete an obstacle training course.
Therefore, the maximum combat load should still be limited to what a soldier can carry comfortably on his own, without hindering any modes of motion. The exoskeletons are really only useful in carrying heavier loads in non-combat situations. However, unlike backpacks, which can be dropped within a 1 sec, the current exoskeleton designs take a lot longer to put on and take off. This is undesirable for combat patrols, since they may encounter an enemy unexpectedly.
For mechanised infantries, the vehicles carry most non-essential loads for them. And the vehicles provide cover, fire support, and strategic mobility. They are still much more versatile than exoskeletons. IEDs are poor-man's weapons against guided missiles, tanks, helicopters etc. They are basically homemade mines. There are a lot more deadly and more advanced anti-vehicular and anti-personal mines available to more advanced militaries. So IEDs are a poor reason for considering the advantages of exoskeletons over vehicles.
So at least in the near future, I see exoskeletons to be useful meanly to logistic sections for carrying heavy loads to areas unsuitable or unreachable by vehicles (including helicopters). E.g. when air-superiority has not been established, and transport helicopters run high risks, and the region is mountainous, forrest, or dense urban, where it would be difficult for military vehicles to manoeuvre; or in situations where heavy equipments needs to be moved into some strategic positions without taking the obvious routes like roads.
But, wearing them in combat I think will still be years away. The exoskeletons can only offset their severe disadvantages in restricting human motion by dramatically increased firepower and armour protection. But you will be looking at armour protection at least on par to that of an APC in vital areas, and that may very much mean the requirement of power assist----thus leading to the issue of power cells.