The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 25, 1986
Filed:
Feb. 17, 1984
Tadashi Gotou, Hitachi, JP;
Fumio Kawamura, Hitachi, JP;
Norihiko Sagawa, Hitachi, JP;
Hideo Yusa, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A sodium-sulfur battery comprising molten sodium as an active material for a minus pole and molten sulfur as an active material for a plus pole, the molten sodium and molten sulfur being partitioned from each other by a sodium ion-permeating solid electrolyte such as .beta.-alumina as a boundary is provided with a sodium storage tank communicated with the molten sodium in the battery cell, a draining mechanism for withdrawing the molten sodium, when desired, from the battery cell into the sodium storage tank, and a circulating mechanism for purifying and returning the sodium from the sodium storage tank to the battery cell as the molten sodium, sodium can be discarged urgently from the battery at an accident of direct contact between the sodium and sulfur, with the result of improved safety. A power storage system comprising a plurality of the sodium-sulfur batteries connected to one another in series and further connected in parallel can be provided with common sodium storage tanks and relevant draining mechanisms, purifying and circulating mechanisms in equal potential level rows of the batteries, resulting in improved economy and safety.