Metal-air battery having folded structure and method of manufacturing the same

1. A metal-air battery comprising:

a negative electrode metal layer disposed on a first side of

a negative electrode electrolyte layer;

a single positive electrode layer disposed on an opposite second side of the negative electrode electrolyte layer, the positive electrode layer comprising a positive electrode material which is capable of using oxygen as an active material; and

a gas diffusion layer disposed on a side of the positive electrode layer which is opposite the negative electrode electrolyte layer,

wherein the negative electrode electrolyte layer is between the negative electrode metal layer and the positive electrode layer,

wherein the positive electrode layer contacts a lower surface and an opposite upper surface of the gas diffusion layer,

wherein one side surface of the gas diffusion layer is exposed to an outside,

wherein the gas diffusion layer comprises a plurality of gas diffusion layers comprising a first gas diffusion layer and a neighboring second gas diffusion layer,

wherein the negative electrode metal layer, the negative electrode electrolyte layer, and the positive electrode layer have a serpentine configuration, and

wherein the positive electrode layer directly contacts a lower surface of the first gas diffusion layer and an upper surface of the second gas diffusion layer, and

wherein the negative electrode metal layer, the negative electrode electrolyte layer, and the positive electrode layer are bent by 180 degrees.

2. The metal-air battery of claim 1 ,

wherein the positive electrode layer contacts lower and upper surfaces of each gas diffusion layer of the plurality of gas diffusion layers.

3. The metal-air battery of claim 2 , wherein, between two adjacent gas diffusion layers, the negative electrode metal layer, the negative electrode electrolyte layer, and the positive electrode layer are bent by 180 degrees so that the negative electrode metal layer is in a folded configuration and the positive electrode layer contacts both of the two adjacent gas diffusion layers.

4. The metal-air battery of claim 2 , wherein a same side surfaces of each gas diffusion layer of the plurality of gas diffusion layers is exposed to the outside.

5. The metal-air battery of claim 1 , further comprising a negative electrode collector which contacts a bend portion of the negative electrode metal layer.

6. The metal-air battery of claim 5 , wherein the negative electrode collector extends in a direction perpendicular to a major surface of each of the negative electrode metal layer, the negative electrode electrolyte layer, the positive electrode layer, and the gas diffusion layer.

7. The metal-air battery of claim 5 , further comprising an outer casing which surrounds the negative electrode metal layer, the negative electrode electrolyte layer, the positive electrode layer, and the gas diffusion layers except for the exposed side surfaces of the gas diffusion layers,

wherein the negative electrode collector is disposed between the negative electrode metal layer and the outer casing.

8. The metal-air battery of claim 1 , wherein an end of the exposed side surface of the gas diffusion layer protrudes from the negative electrode metal layer, the negative electrode electrolyte layer, and the positive electrode layer.

9. The metal-air battery of claim 8 , further comprising a positive electrode collector disposed on a protruding end of the gas diffusion layer.

10. The metal-air battery of claim 1 ,

wherein the negative electrode electrolyte layer comprises a separation layer which is ionically conductive and substantially impermeable to oxygen, and an electrolyte,

wherein the separation layer comprises a porous film, and

wherein the electrolyte is disposed in pores of the porous film.