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:
Oct. 12, 2021
Filed:
Nov. 16, 2018
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Kenji Takahashi, Toyota, JP;
TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota, JP;
Abstract
A secondary battery system includes an electronic control unit (ECU) that estimates surface stress generated in a negative-electrode active material upon incorporation or removal of lithium in a negative electrode of a battery assembly. The ECU calculates an estimated value of the surface stress from a difference obtained by subtracting a reference lithium amount from an amount of lithium contained in the negative-electrode active material, using a linear relationship between the difference and the surface stress. The ECU sets the surface stress to yield stress when the magnitude of the estimated value is larger than that of the yield stress (compressive stress or tensile stress) of the active material, and employs the estimated value as the surface stress when the magnitude of the estimated value is smaller than that of the yield stress.