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:
Nov. 08, 2011
Filed:
Jan. 23, 2008
Jian Lin, Beverly Hills, MI (US);
Brian J. Koch, Berkley, MI (US);
Damon R. Frisch, Troy, MI (US);
Michael J. Gielniak, Romeo, MI (US);
Jian Lin, Beverly Hills, MI (US);
Brian J. Koch, Berkley, MI (US);
Damon R. Frisch, Troy, MI (US);
Michael J. Gielniak, Romeo, MI (US);
GM Global Technology Operations LLC, Detroit, MI (US);
Abstract
A method for rapidly determining an initial diffusion voltage (V)as a starting point in calculating a diffusion voltage in an electro-chemical cell (e.g., a battery used in an automotive vehicle) includes obtaining a time difference tbetween a time when the cell was last turned-OFF and a time when the cell was next turned-ON, selecting a starting diffusion voltage (V)based on t, determining a trial diffusion voltage Vbased on a diffusion circuit model and (V), calculating an error voltage V=(V)−|V−V| where Vand Vare cell voltages at turn-OFF and turn-ON respectively, repeating the foregoing determining and calculating steps using for each iteration (V)=(V)+Vuntil Vis less than or equal to a first predetermined tolerance amount ε, storing in a memory a value of Vcorresponding to the condition V≦ε, and setting (V)equal to the just stored value of V. A further diffusion voltage Vis then determined using the same diffusion circuit model and the just obtained (V)and is advantageously used by a controller in an electric propulsion vehicle to determine a state of charge of the propulsion battery.