Hydride bottles

A hydride bottle, complete with attendant valves that can be easily con-nected to whatever apparatus you want to feed hydrogen to, can be purchased, which is the easiest way to go. There are suppliers in the resources I list starting on page 348. 

You can also do it yourself and buy your own hydrides, a bottle, and attendant fixtures. If you are interested in this approach there is more information available in The Solar Hydrogen Chronicles. 

When purchased, hydride bottles are initially activated by charging with hydrogen for extended periods of time, and/or at higher temperatures and/or at higher pressures. The particular process depends on the nature of the alloy used. It is common practice for the supplier to do the initial charge, however you can activate the bottle yourself. 

The manufacturer (HCI) of this particular hydride bottle has several different hydride formulas available which they designate as A, L, M, and H. The bottle in the photos contain this manufacturers alloy A which is considered a nonflammable solid when discharged. This means that it can be shipped without hazmat charges. The manufacturer will initially charge the bottle, then de-charge and ship it to you. The L, M, and H alloys that they offer are considered flammable solids and must be shipped as hazardous materials with the extra hazmat charge. 

This particular iron/titanium alloy requires a pressure of 400 psig to charge effectively. Lower pressures can be used to charge the alloy, but it will not charge to its full storage capacity. 

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If the gas production is a supply for recharging hydride bottles, the gas should be as dry as possible. Moisture deteriorates the performance of the hydrides in the bottle. If you use the hydride bottles to supply a fuel cell system, it may be necessary to re-moisturize the hydrogen by running it through a bubbler. 

Generally speaking a 0-100 psi gauge will meet a wide range of needs, unless you are refilling hydride bottles which will require higher pressures. 

Charging is a simple procedure. You need a gas source that can deliver 400 psig and a regulator that can deliver 400 psig at the outlet. Most hydride bottles are filled from commercial high pressure hydrogen cylinders. 

The cylinder regulator is connected to the hydride bottle by a flexible stainless steel hose with a Vs" male NPT on one end and a Vs" NPT male fit-... 

DESO stem used to connect to hydride bottle... 

This DESO stem fits on to the Swagelok quick-connect DESO body on the hydride bottle. Depending on the regulator you choose, the Ys" NPT male end of the hose will either fit into the port on the regulator, or the regulator will have a 34" NPT female outlet. If it has a 34" NPT outlet, use a Vs" female x 34" male adapter to connect to the regulator. 

To charge the hydride bottle, connect the hydride bottle to the cylinder regulator via the DESO stem connection. 

When the cylinder charges it will become very warm. When it is done charging, it will cool down. You can speed up the charging process a bit by placing the hydride bottle in a container of cold water. 

Remove the quick-connect stem on the hose from the hydride bottle. click here for Charging the hydride bottle in print format... 

To use the hydride bottle, connect a braided hose with DESO stem and a small regulator to the bottle. The other end of the hose will have the connection that goes to your particular hydrogen device, such as fuel cell stack. 

Most hydrogen fueled devices use around 2 to 6 psi, and not over 15 psi, although there are some that use 25 psi. Whatever your application, you must use a regulator that has the precision needed to Connect regulator to hydride bottle work in the correct pressure range... 

Regulator for hydride bottle Fuel Cell Store 595618 1... 

Remove the quick-connect stem on the hose from the hydride bottle. 

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