Secondary battery

A secondary battery comprising:

• a substrate;
• a first current collector;
• a first electrode;
• a solid electrolyte;
• a second electrode;
• and a second current collector;
• said first current collector being formed on said substrate and serving as a current collector of said first electrode,
• said first electrode being formed on said first current collector,
• said solid electrolyte being formed on said first electrode,
• said second electrode being formed on said solid electrolyte,
• said second current collector being formed on said second electrode and serving as a current collector of said second electrode,
• at least one of said first and second electrodes containing an electrode material and at least one conductive material which is different from said electrode material, said different conductive material comprising at least one of an ion conductive material and an electron conductive material,
• wherein said at least one electrode contains at least said electron conductive material, said electron conductive material extending in a thickness direction of said electrode to form at least one electron conducting path connected with the current collector thereof, and
• wherein the amount of said electron conductive material forming said electron conducting path decreases from the current collector side to the solid electrolyte side.