Toa Nenryo Kogyo Kabushiki Kaisha

Tonen Corporation

Isao Mukaizawa

Hiroyuki Iwasaki

Toshihiko Yoshida

Fumiya Ishizaki

Satoshi Sakurada

Nobuaki Tagaya

Yoshiyuki Someya

Osamu Yamamoto

Tsukasa Shima

Hiroshi Seto

The mechanical strength of stabilized zirconia is improved without lowering the ion conductivity by providing a solid electrolyte comprising stabilized zirconia and a metal oxide dispersed within grains or grain boundaries of stabilized zirconia, the metal oxide having an average submicron particle size and stabilized zirconia having an average particle size larger than 1 micron, typically larger than 10 .mu.m or even 100 .mu.m.

Stabilized zirconia solid electrolyte and process for preparation thereof

The present invention provides a solid electrolyte type of fuel cell of a planar type structure comprising a plurality of solid electrolyte plates, each being in the form of a flat plate and having a porous cathodic layer on one side and a porous anodic layer on the other side, which are laminated together through an interconnector plate provided in both its sides with grooves defining gas passages, wherein oxidizing agent and fuel gases are fed through said passages to the cathodic and anodic sides, thereby reducing the length of a current path running through regions of high resistance, increasing the degree of integration and improving reliability. By using heat-resistant parts for the interconnectors, cathodes and anodes, it is also possible to improve the resistance to oxidation and reduction as well as durability and obtain low resistance. it is further possible to obtain a fuel cell having satisfactory properties and capable of standing up to use over an extended period of time by using solid electrolyte for fuel cells which is obtained by sintering Y.sub.2 O.sub.3 -containing partially stabilized zirconia added with 5 to 20 % of alumina, has low resistance and high mechanical strength and is stable.

Solid electrolyte type fuel cells

Growing community of inventors

Saitama, Japan

Isao Mukaizawa