I’ve not familiar with the product at all but I’m always skeptical of any additive that promises the world. If this product actually worked then one should ask themselves why the battery manufacturers are not dribbling a bit of this stuff into every battery they make. What better way to prevent pro-rated battery returns and especially considering the fact the battery makers could produce this stuff themselves for pennies.
What I would really be concerned about is the bit about “cadmium”. I have no idea what any cadmium substances would do in a battery but cadmium plating can produce cyanide gas and one whiff of that could send you to the graveyard pretty quickly.
That is one reason why many plating operations (other than aircraft) have done away with cadmium plating, which is not to be confused with Copy Cad plating (similar in appearance only).