Makes powercells produced by the protolathe start uncharged.

code/modules/research/circuitprinter.dm

@@ -195,7 +195,7 @@ using metal and glass, it uses glass and reagents (usually sulphuric acid).
 		reagents.remove_reagent(C, D.chemicals[C] * mat_efficiency)
 
 	if(D.build_path)
-		var/obj/new_item = new D.build_path(src)
+		var/obj/new_item = D.Fabricate(src)
 		new_item.loc = loc
 		if(mat_efficiency != 1) // No matter out of nowhere
 			if(new_item.matter && new_item.matter.len > 0)

code/modules/research/designs.dm

@@ -55,6 +55,11 @@ other types of metals and chemistry for reagents).
 		desc = "Allows for the construction of \a [item_name]."
 	return
 
+//Returns a new instance of the item for this design
+//This is to allow additional initialization to be performed, including possibly additional contructor arguments.
+/datum/design/proc/Fabricate(var/newloc)
+	return new build_path(newloc)
+
 /datum/design/item
 	build_type = PROTOLATHE
 
@@ -212,6 +217,11 @@ other types of metals and chemistry for reagents).
 		var/obj/item/weapon/cell/C = build_path
 		desc = "Allows the construction of power cells that can hold [initial(C.maxcharge)] units of energy."
 
+/datum/design/item/powercell/Fabricate()
+	var/obj/item/weapon/cell/C = ..()
+	C.charge = 0 //shouldn't produce power out of thin air.
+	return C
+
 /datum/design/item/powercell/basic
 	name = "basic"
 	build_type = PROTOLATHE | MECHFAB

code/modules/research/protolathe.dm

@@ -196,7 +196,7 @@
 		reagents.remove_reagent(C, D.chemicals[C] * mat_efficiency)
 
 	if(D.build_path)
-		var/obj/new_item = new D.build_path(src)
+		var/obj/new_item = D.Fabricate(src)
 		new_item.loc = loc
 		if(mat_efficiency != 1) // No matter out of nowhere
 			if(new_item.matter && new_item.matter.len > 0)