US 11,888,194 B2
Method for distinguishing the cause of voltage losses in a fuel cell device, fuel cell device and motor vehicle having such a device
Oscar Montoya, Ludwigsburg (DE); and Kai Müller, Bretzfeld (DE)
Assigned to Audi AG, Ingolstadt (DE)
Appl. No. 17/775,853
Filed by AUDI AG, Ingolstadt (DE)
PCT Filed Jun. 17, 2021, PCT No. PCT/EP2021/066390
§ 371(c)(1), (2) Date May 10, 2022,
PCT Pub. No. WO2022/053191, PCT Pub. Date Mar. 17, 2022.
Claims priority of application No. 102020123782.0 (DE), filed on Sep. 11, 2020.
Prior Publication US 2023/0216075 A1, Jul. 6, 2023
Int. Cl. H01M 8/04992 (2016.01); H01M 8/04537 (2016.01)
CPC H01M 8/04992 (2013.01) [H01M 8/04559 (2013.01); H01M 2250/20 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A method for distinguishing a cause of voltage losses in a fuel cell device, comprising:
detecting a quasi-stationary operation of the fuel cell device;
acquiring and storing a measured current-voltage characteristic curve with current values and voltage values of a fuel cell stack of the fuel cell device;
using a PtOx model to determine PtOx voltage losses and calculating a corrected current-voltage characteristic curve for the PtOx-free and normally humidified fuel cell stack; and
comparing the measured and corrected current-voltage characteristic curves and detecting an at least partially dried-out fuel cell stack if the measured current-voltage characteristic curve runs below the corrected current-voltage characteristic curve.