Where do I find the power cells to restore the bunker door in “Ancient armory”?

I am trying to find the power cells to access the amor. Yet the placement is unmarked and I thought I would eventually stumble over them clearing the cauldrons.

Yet after clearing three cauldrons (RHO, XI, and Sigma) I still only have the one from the very beginning.

Where do I find all the power cells?

Solution 1:

This guide here lays out where all five of the cells are:

1. The Underground Bunker in the prologue. Once you are adult Aloy, go back to this locations. The cell is located on the other side of some stalactites and stalagmites inside of the bunker.

2. The All-Mother Temple. After or during the Womb of the Mountain quest, this cell can be found through two doors and a vent after you awake.

3. Makers End. The guide recommends getting this one during the quest that is also named Makers End, since you will have climbed the tower already. Once at the top of the tower on the rooftop, turn around and see a bronze looking spire. Climb the spire, and the power cell is on top of it.

4. The Grave-Hoard. You can get this one either during or after the quest called The Grave-Hoard. Enter the ruins, solve the puzzles, climb up the ledge and open the door in front of you. The power cell will be in front of you along with some supplies.

5. Inside the GAIA Prime ruins. This is towards the end of the main story line quests. You can get it once you begin The Mountain That Fell quest. After proceeding through the ruins, you will reach a zipline outside. After dropping off of the zipline, turn around. You'll see a handhold on a rock that you can climb. After climbing, you will see a purple looking entrance to a small cave. At the end of the cave, is the power cell.

_{All image links are from the above linked guide}