Patent ID: 8097380

Claim:
A fuel cell unit incorporated in a fuel cell device comprising: a tubular fuel cell body having a tubular inner electrode layer, a tubular outer electrode layer, a tubular electrolyte layer disposed between the inner and outer electrode layers, and a through passage formed inside of the inner electrode layer; an inner electrode terminal fixed at one end of the fuel cell body configured to take out electricity from the inner electrode layer; and an outer electrode terminal fixed at the other end of the fuel cell body configured to take out electricity from the outer electrode layer; wherein the fuel cell body has, at the one end thereof, an inner electrode exposed periphery where the inner electrode layer is exposed and extends further in a longitudinal direction than the electrolyte layer and the outer electrode layer; wherein the fuel cell body has, on a peripheral surface at the one end thereof, an inner electrode peripheral surface electrically communicating with the inner electrode layer via the inner electrode exposed periphery, and, on a peripheral surface at the other end thereof, an outer electrode peripheral surface electrically communicating with the outer electrode layer; wherein the inner electrode terminal has a cylindrical body portion disposed so that it covers over the entire circumference of the inner electrode peripheral surface from the outside thereof and it is electrically connected thereto, and a cylindrical tubular portion extending from the body portion in a direction away from the fuel cell body in the longitudinal direction, a diameter of the tubular portion of the inner electrode terminal being smaller than a diameter of the body portion of the inner electrode terminal; wherein the outer electrode terminal has a cylindrical body portion disposed so that it covers the entire circumference of the outer electrode peripheral surface from the outside thereof and it is electrically connected thereto, and a cylindrical tubular portion extending from the body portion in a direction away from the fuel cell body in the longitudinal direction, a diameter of the tubular portion of the outer electrode terminal being smaller than a diameter of the body portion of the outer electrode terminal; and wherein the inner electrode terminal and the outer electrode terminal have respective connecting passages which are communicated with the through passage and the exterior of the fuel cell body.