Do keep in mind that you may need to have progressed to a certain point in the story (denoted below) to reach the required locations, but you can always return to these areas if you've already beaten the game.

In order to get the Shield-Weaver outfit in Horizon Zero Dawn, you'll need to locate five Power Cells around the game world which can then be taken to the Ancient Armory in order to solve a couple of door puzzles. Horizon Zero Dawn: All Power Cells Locations

For an exact explanation, as well as locations, you can check this video.

Horizon Zero Dawn: How to Get the Shield-Weaver Outfit Keep in mind in order to obtain them all, you need to beat a good portion of the game.

Completing this quest unlocks the Got the Shield-Weaver Trophy.

Horizon Zero Dawn: All Power Cells Locations This page contains the walkthrough for the Ancient Armory side quest, as well as the hidden Power Cell locations in Horizon Zero Dawn.

You'll also pick up the Got the Shield-Weaver Outfit Trophy along the way. How do you get the Shield-Weaver outfit in Horizon Zero Dawn? And what are all Power Cells locations? As part of our Horizon Zero Dawn guide, we're going to help you recover an ancient technology and put it to use by explaining how to complete the Ancient Armory side-quest, find all Power Cells, and unlock the best armour in the game, which effectively makes you invincible to enemy attacks.

Horizon zero dawn power cell locations