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:
Aug. 09, 2011
Filed:
Apr. 23, 2007
Karim Zaghib, Québec, CA;
Michel Gauthier, Québec, CA;
Gabrielle Nadeau, Québec, CA;
Abdelbast Guerfi, Québec, CA;
Monique Massé, Québec, CA;
Fernand Brochu, Québec, CA;
Michel Armand, Queébec, CA;
Karim Zaghib, Québec, CA;
Michel Gauthier, Québec, CA;
Gabrielle Nadeau, Québec, CA;
Abdelbast Guerfi, Québec, CA;
Monique Massé, Québec, CA;
Fernand Brochu, Québec, CA;
Michel Armand, Queébec, CA;
Hydro-Quebec, Quebec, CA;
Abstract
The present invention relates to the physical or chemical specific purification of natural mineral graphite. This purification is preferably applied to the surface of natural graphite in order to allow the formation of a passivation film during the first electrical discharge or the insertion of lithium in the graphite when the latter is used in a lithium-ion cell. The grinding to a small size before purification allows the optimization of the distribution of the particles, resulting in a more uniform electrode. This grinding is carried out in the presence of the natural impurities of the graphite that play the role of a micro-abrasive and result in a hardness of the graphite that increases its mechanical properties.