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:
Apr. 21, 2015
Filed:
Jan. 23, 2012
Mark W. Verbrugge, Troy, MI (US);
Sampath K. Vanimisetti, Karnataka, IN;
Ramakrishnan Narayanrao, Karnataka, IN;
Mark W. Verbrugge, Troy, MI (US);
Sampath K. Vanimisetti, Karnataka, IN;
Ramakrishnan Narayanrao, Karnataka, IN;
GM Global Technology Operations LLC, Detroit, MI (US);
Abstract
The gravimetric and volumetric efficiency of lithium ion batteries may be increased if higher capacity materials like tin and silicon are substituted for carbon as the lithium-accepting host in the negative electrode of the battery. But both tin and silicon, when fully charged with lithium, undergo expansions of up to 300% and generate appreciable internal stresses. These internal stresses, which will develop on each discharge-charge cycle, may lead to a progressive reduction in battery capacity, also known as battery fade. The effects of the internal stresses may be significantly reduced by partially embedding tin or silicon nanowires in the current collector. Additional benefit may be obtained if a 5 to 50% portion of the nanowire length at its embedded end are coated or masked with a composition which impedes lithium diffusion. Methods for embedding and masking the nanowires are described.