A lathe-cutting apparatus and a method with a structure of a chuck being simple, which are capable of lathe-cutting an eccentric part of a crankshaft with high accuracy are provided. Furthermore, the architecture of the illustrative embodiment ameliorates the well-known \u201cadd-before-drop\u201d problem. A first layer of phase change material is between the first and second electrodes. The SOC if the battery is calculated from the open circuit voltage. Since there are some components of the image portion even in the compensated desired signal, that signal indicative of the image portion is used to compensate for that undesired portion.