Spin coating method and device and preparation method of thin film battery

The invention relates to a spin coating method and device and a preparation method of a thin film battery. The spin-coating method comprises the steps that a substrate to be spin-coated is integrally arranged in a manner of deviating from a rotation center, the substrate is obliquely arranged relative to a rotation plane, and an included angle alpha, 0 degree lt is formed between the back face of the substrate and the rotation plane; an included angle alt; and the spin-coating liquid is placed on one side of the bottom of the front face of the substrate and rotates around the rotation center through the substrate, the spin-coating liquid extends upwards from the bottom to cover the front face of the substrate, and spin-coating is completed. The spin coating device comprises a rotating mechanism and a substrate fixing mechanism. According to the preparation method of the thin film battery, spin coating preparation of the functional film layer of the thin film battery is carried out by adopting the spin coating