The fuel cell charger that generates electricity from water and salt

The site says everywhere that it uses salt, but this is misleading. It's not table salt, it's a special salt. (Using table salt to generate energy is ridiculous.) For example, the site tries to ensure the product is safe because it only use salt and water, but it's not the salt that everyone imagines.

Now, if it uses a special salt, what's the difference between this and an usual AAA battery?

From the FAQ:

> What is myFC Puck made of?

> The body of the Puck is an aluminum can that holds the binary fuel, Sodium silicide and Sodium borohydride (CAS number: 12164-12-4 & 16940-66-2). The aluminum can is then permanently attached to a plastic cap, which is used to control the release of hydrogen gas to the fuel cell. After the fuel mixture is fully reacted, the Puck will contain two benign by-products (sodium silicate and sodium metaborate).

> Both by-products are chemically benign, non-hazardous, and safe. In fact, these by-products are used in many industrial manufacturing processes and many common household products (like concrete, detergent, glass, makeup, and toothpaste) are produced using these materials.