Kabushiki Kaisha Toyoda Jidoshokki Seisakusho

Other

Kazuhiko Itoh

Hidehito Kubo

Keiji Toh

Hiroyuki Mitsui

Katsuyoshi Fujita

Shinya Morishita

Shinichi Towata

Makoto Ishikura

Shin-ichi Towata

Hiroshi Kawase

Katsushi Abe

Hideki Morino

Shunsuke Yamakawa

Yutaka Ohya

Sinichi Towata

An HM reservoir for storing hydrogen includes a housing and a plurality of storage units. The storage units are stacked in the interior of the housing. Each storage unit includes a pair of plate-like molded bodies and a flat heat exchanger. The plate-like molded bodies are formed by compressing powder of hydrogen storage material. The heat exchanger is provided between the molded bodies. Each molded body includes a first side and a second side, which is opposite to the first side. The first side contacts the heat exchanger. A plurality of flat hydrogen passages are formed in the interior of the housing to face the second sides of the associated molded bodies. The structure of the HM reservoir is thus simple. Further, the molded bodies of the HM reservoir smoothly absorb hydrogen and smoothly release the same.

Reservoir with hydrogen storage material

Methods for making hydrogen storage tanks may include disposing a substantially solid block of hydrogen-absorbing alloy within an activation vessel. Hydrogen gas may then be introduced into the activation vessel under conditions that will cause the hydrogen-absorbing alloy to absorb hydrogen and crack or break apart. Preferably, a substantially powdered hydrogen-absorbing alloy is formed thereby. Thereafter, the substantially powdered hydrogen-absorbing alloy can be transferred from the activation vessel to a hydrogen storage tank without substantially exposing the powered hydrogen-absorbing alloy to oxygen. The hydrogen-absorbing alloy is preferably ingot-shaped when introduced into the activation vessel. Further, the substantially powdered hydrogen-absorbing alloy is preferably produced by continuously breaking the ingot-shaped hydrogen-absorbing alloy within the activation vessel due to volume expansion caused by the hydrogen-absorbing alloy having absorbed hydrogen. The hydrogen gas preferably contacts the hydrogen-absorbing alloy under relatively high-pressure and low temperature conditions.

Methods for manufacturing hydrogen storage tanks

Steam is contacted with a hydrogen absorbing alloy in a temperature range from 200.degree. C. to 400.degree. C. With a contact catalytic reaction of water, a metal contained in the hydrogen absorbing alloy is changed to an oxide or a hydroxide. Hydrogen produced causes the Ni compound to be reduced and thereby the Ni metal that is catalytically active is produced. Thus, the surface of the hydrogen absorbing alloy is activated. The steam is contained in an inert gas or a reductive gas. This treatment method is suitable as an activation treatment for a hydrogen absorbing alloy used as an active material of a negative electrode of a secondary battery.

Surface treatment method of hydrogen absorbing alloy

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Aichi-ken, Japan

Kazuhiko Itoh