Hydrogen storage alloy has for quite some time now been attracting attention as a single unit for the storage and transport of hydrogen. Although not going so far as to be called an explosive demand in terms of performance and price, nevertheless the demand for nickel hydride battery for use with hybrid vehicles (HV) is expanding. Accordingly the demand, which had dropped by half in 2005, is gaining ground again, reaching an annual level of 10,000 tons.

Hydrogen storage alloy reacts with hydrogen and forms metallic hydride. A feature of this metal is that when it is heated the stored hydrogen is released. As of this time over 90% of the application is for nickel hydride batteries for daily use by consumers and for batteries used with hybrid vehicles.

Annual production in the market overall came to about 10,000 tons last year, with the players in this field being Japan Metals and Chemicals, Mitsui Metals, Chuden Rare Earth, and Santoku Industries. The price is in general is around 2,000-5,000 yen a kilogram and is greatly controlled by the import price of rare earth, which accounts for about 40% of the raw material used. Since the appearance of a problem with China regarding rare earth, the development of a storage alloy using magnesium and a change of the country from which the raw material is imported are now under consideration as national projects. As for the amount used, in the case of the nickel storage batteries for private use this amounts to about 6 grams for a AAA battery.

The demand is linked to the demand for nickel hydride batteries. In the case of lithium ion batteries, in 2005 the amount came to 5,000 tons, a temporary decline. With the appearance of hybrid vehicles, however, the trend has been one toward recovery. In addition, the Fuel Cell Commercialization Conference of Japan is aiming at 2 million fuel cell vehicles in operation by 2025. Because of this it seems that the producers are placing their hopes on fuel cell vehicles as a new source of demand.

Aiming at a 10% reduction in the price for cells mounted on cars and a 5 fold increase in storage

At Japan Metals and Chemicals, a leading producer of hydrogen storage alloy, it has been provisionally calculated that, “if 2 million fuel cell vehicles go into use by 2025, the overall demand for hydrogen storage alloy will reach 20,000 tons a year, double the current amount.”

The company is a long standing producer which became involved in the development of hydrogen storage allow in 1979. In 2002 as part of the New Energy and Industrial Technology Development Organization (NEDO) project WE-NET it sold a large hydrogen storage allow tank to a hydrogen station in Osaka. In April of this year in conjunction with Honda it became involved in the recovery of rare earth. The company is therefore also putting effort into the business of the functional material in addition to that of the hydrogen storage alloy. The company has an annual production capacity of 6,000 tons. Half of its sales is for the negative electrode of nickel hydride batteries for the private sect while the other half is for use with fuel cells.

According to the Functional Materials Division regarding the status of development, “Right now 1 cc of alloy can absorb 1 liter of hydrogen but we are aiming at having 1cc of alloy being able to absorb 5 liters. The price for use with car is 30,000 yen a kilo, but we need to reduce this down to 1,000-2.000 yen a kilo.”

Regarding hydrogen tanks, the latest one is a tank which enables continuous running at a speed of 100 km/h for 2 hours which was developed last year for the NEDO business. They are striving for a reduction of the weight of the heat exchanger of which a weight is now 90kg.