What phrase structure is self-cultivation energy storage?

Self-cultivation and energy storage are juxtaposed phrases, which consist of two words: self-cultivation and energy storage. There is no relationship between these two words, such as modification or modification, nor domination or control, but they each express independent meanings. "Self-cultivation" usually refers to self-cultivation to improve one's moral character and quality. In the traditional culture of China, "self-cultivation" is an important concept, which emphasizes that individuals should pay attention to their own moral cultivation and spiritual realm. "Energy storage" refers to the accumulation of energy, which is usually used to describe the accumulation of strength to prepare for action or meet future challenges. In modern society, "energy storage" is also widely used in various fields, such as energy storage technology in the energy field and reserve funds in the economic field.