We have developed a newly designed high efficiency spectrometer system for ultra-soft X-rays with a VLS (Varied-Line-Spacing) grating and a two-dimensional CCD detector. This system can be adapted to the analysis of Li with Li Kα at high sensitivity. A polycapillary system is set in the upstream of the instrument as an X-ray lens to condense the ultra-soft X-rays for high efficiency measurement. There are no moving parts such as slit and drive system of grating in this system at all. And, these advantages make it possible to construct the high-resolution ultra-soft X-ray spectrometer with maximum possible desiring transmission efficiency and reproducibility. This instrument can be applied to the precision analysis of the chemical state of Li metallic, which is one of the key elements of the industrial materials such as an electrode material used for a fuel cell or a lithium battery for controlling the process of the reaction with an electrolyte.