On this Ratchet & Clank Rift Apart game guide page, we answer the question of whether real shields can be used in the game to increase the defensive capabilities of the characters. In addition, you will learn how to use energy shields.
As you progress through Ratchet & Clank Rift Apart, you can collect armor pieces, but they do not add any new energy bars or lengthen your health bar. They only allow you to unlock various passive stat bonuses, which you will retain from the moment you acquire each piece of armor until the end of the game (i.e. even after removing a particular armor piece).
What you won't find in the game are physical shields, i.e. ones that Ratchet and Rivet could hold in their right hand and shield themselves with.
The fact that you can acquire a weapon that allow you to generate energy shields is at least some consolation. Specifically, we mean the Void Repulser, which costs 17500 bolts and first becomes available for purchase from Mrs. Zurkon in the final part of your first visit to planet Savali.
The Void Repulser functions in two main modes. Pressing R2 halfway generates a shield that is capable of stopping enemy ranged attacks. However, keep in mind that every deflected projectile depletes the energy (ammunition) of the Vacuum Cleaner. Always keep an eye on the small energy bar of your weapon, so you won't be surprised if the Void Repulser suddenly turns off and exposes your hero to enemy attacks.
The Void Repulser is of course worth upgrading further by spending raritanium on weapon upgrades. Among other things, you will be able to increase the total amount of available energy.
It is equally important to get the Void Repulser to level 5 through frequent usage. This will transform the Void Repulser into a better weapon, the Void Reactor. This enables the shield to be able to additionally "store" stopped projectiles, which are marked by purple dots appearing on the shield (example marked in the screenshot). You can send these gathered projectiles back towards your enemies by pressing the R2 button all the way down.