Final Fantasy XV released for PS4 and Xbox One in Nov 2016.  To upgrade the Bio Blaster, you need an item called as Dynamo. You need to start the quest A Better Bioblaster in order to perform this upgrade. This dynamo locations guide will show the location of the Dynamo in the game.

Final Fantasy XV Dynamo Locations

Location 1

• In A King’s Struggle quest in Chapter 13 where you activate the central elevator to reach the warehouse, a dynamo can be found.
• Go to the lower level of the warehouse and head north.
• Search between the canister racks for a staircase.
• Climb it to reach a platform with the dynamo.

Location 2

• This one is located in the north-west area of the map.
• It is located towards the west of Coernix Bypass and towards the south-west of the Burbost Souvenir Emporium.
• Go inside the cave behind the waterfall.
• Follow the river to reach the area with the treasure spot.
• Take down the level 50 snake guarding that area to get the Dynamo.

You can find the complete Final Fantasy XV Guide here.