There is provided a substrate for electronic devices, in which treatment for forming a reconstructed surface or a hydrogen-terminated surface on a substrate is not necessary, and a buffer layer formed on the substrate can be epitaxially grown in the orientation, and a manufacturing method therefor. For wavelength division multiplexing, the system has a map strength preferably between 4 and 8. The first angular dimple includes a first surface that forms an angle relative to a first plane of the first substrate. When charging or discharging the battery, the optimized battery-charging system calculates a rate of charge or discharge that assures that the battery temperature does not exceed a preconfigured maximum value.