Patent ID: 11901501
Assignee: PANASONIC HOLDINGS CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 0:
1. A secondary battery comprising:
a wound electrode group;
an electrolyte;
a cylindrical battery case that houses the electrode group and the electrolyte;
a sealing body that seals an opening of the battery case and includes a discharge valve; and
an insulating plate disposed between the electrode group and the sealing body,
wherein the insulating plate has a disk shape with a thickness T of 0.1 mm or more,
the insulating plate has a first hole formed centrally therein and at least one second hole,
a ratio (=T/D) of the thickness T to a diameter D of the insulating plate is 0.016 or less, and
the insulating plate has an opening ratio of 36% or less,
wherein the first hole is smaller than at least one of the at least one second hole.