The Horizon Fuel Cell HYDROSTIK Cartridge is used in the MINIPAK and has a battery-like form factor. The HYDROSTIK contains a special metal alloy that allows hydrogen to be stored in a solid-state, as part of the metal alloy matrix inside the cartridge. In contrast with ordinary compressed hydrogen tanks, the pressure inside the canister is very low, making this device the safest and most practical means of storing hydrogen. The HYDROSTIK has the additional advantages of being refillable (from pressurized gas bottles, or from water-electrolysis based devices), non-toxic, eco-friendly, and competitive on cost/performance with existing battery devices. Each HYDROSTIK can store 15Wh of energy, enough for 1-2 charges of a 3G smartphone, or 2-3 charges for average cellphones, which is more than what present primary and rechargeable batteries are able to offer at equivalent cost. HYDROSTIK can be made available in bulk for refill using industrial gas, providing a low-cost portable energy option for users. When using industrial hydrogen gas, the overall energy efficiency of the Minipak is higher than batteries being recharged from the power grid (when counting power plant efficiency, power line losses, and typical AC/DC efficiency of chargers). IMPORTANT CLARIFICATION: 1 HYDROSTIK = 10 disposable AA batteries at 1W continuous power consumption. This is because at 1W power consumption, most AA batteries can only last one hour, while the HYDROSTIK has enough energy to last 10 hours. If 1 HYDROSTIK is then refillable 100 times, the sameHYDROSTIK can replace 10x100 or 1000 disposable AA batteries over its lifetime E (INCLUDING MULTIPLE REFILLS) - when the required continuous power is 1W.