| CPC G01N 27/4077 (2013.01) [G01M 15/102 (2013.01)] | 6 Claims |

|
1. A gas sensor element comprising:
an element body including an oxygen-ion-conductive solid electrolyte layer; and
a protective layer that covers at least part of the element body, and has a thermal conductivity ratio R of 1.6 or higher, the thermal conductivity ratio R (=λs/λt) being a surface direction thermal conductivity λs [W/m K] to a thickness direction thermal conductivity λt [W/m K].
|