Abstract: The present invention provides a lithium secondary cell containing a positive electrode including a material which occludes and exudes lithium; a negative electrode containing a negative material including graphite; and a separator disposed between the positive and negative electrodes; wherein the quantity of lithium occluded in the negative material in a fully-charged state is less than 55% of the theoretical lithium occlusion capacity of the negative electrode.

Abstract: A sealed type battery is disclosed which can reduce variations in the operating pressure of a safety valve, improve the reliability for the airtightness of a battery vessel, remove the contact of electrode plates and the case due to the rightward or leftward deviation of a group of electrode plates in the direction of the winding shaft, remarkably reduce the internal short-circuiting production rate, and realize cost lowering or reduction in the number of working steps. The battery is equipped with a safety valve in which a cover plate having a hole, a metal thin plate and a holding plate of metal having a hole are stacked with the metal thin plate sandwiched and integrally fixed by laser welding.