An exemplary battery is provided in the present invention. The battery comprises a carbon rod, a positive-electrode structure, a separation structure, a negative-electrode structure and a housing. The positive-electrode structure, the separation structure, the negative-electrode structure and the housing encircle the carbon rod in sequence. At least one of the positive-electrode structure and the negative-electrode structure contains chlorophyll. The battery of the present invention stores hydrogen by the chlorophyll to generate electricity. Thus, not only is the manufacturing process of the battery simple, and economical, but also natural, non-toxic substances are employed, unlike the conventional batteries, the battery of the present invention will not cause environmental pollution even when discarding after being used.