Patent ID: 6733925
Filing Date: 2004-05-11
Classification: H01M,Y02E,Y02P,Y02T

Abstract:
A non-aqueous electrolytic solution secondary battery comprising a winding group and a non-aqueous electrolytic solution accommodated in a battery container,said winding group comprising a positive electrode and a negative electrode wound through a separator; said positive electrode comprising a positive electrode collector applied with a positive electrode mixture, said positive electrode mixture comprising a positive electrode active material from/in which lithium-ions can be released/occluded through charging/discharging; said negative electrode comprising a negative electrode collector applied with a negative electrode mixture, said negative electrode mixture comprising a negative electrode active material in/from which lithium-ions can be occluded/released through discharging/charging; and said non-aqueous electrolytic solution comprising a lithium salt dissolved into organic solvent; wherein, said winding group is infiltrated into the non-aqueous electrolytic solution; porosity of the separator is larger than or the same as porosity of the positive electrode mixture and porosity of the negative electrode mixture; and an electric capacity of said secondary battery is more than 15 Ah; and wherein, when a layer thickness of the positive electrode mixture applied on both surfaces of the positive electrode collector ranges from 200 &mgr;m-300 &mgr;m, the porosity of the positive electrode mixture layer is set in accordance with formula (1), wherein xp is a number equal to the layer thickness, yp is the porosity, and 15%&lE;bp&lE;20%: yp=5%(xp)+bpâ€ƒâ€ƒ(1).