CRYSTALLIZED GLASS AND METHOD FOR PRODUCING THE SAME

The crystallized glass according to the present invention contains a LiVOPO 4 crystal. The LiVOPO 4 crystal is preferably a ²-LiVOPO 4 crystal. In addition, the crystallized glass according to the present invention preferably contains a composition of Li 2 O: 25-60%, V 2 O 5 : 20-40% and P 2 O 5 : 20-40% in terms of mol%. The crystallized glass according to the present invention is suitable as a positive electrode material for lithium ion secondary batteries. The present invention provides a substance suitable as a positive electrode material for a lithium secondary battery having good battery properties and a method for producing the substance.