Method and system for improving battery capacity estimations

US11255917B2 · kind B2 · utility

Assignee

• VOLVO CAR CORPORATION · SE

Inventors

• Anton KLINTBERG · Gothenburg, SE
• Torsten Wik · Gothenburg, SE
• John Skötte · Gothenburg, SE
• Marcus Hedegärd · Mölndal, SE
• Louise Almquist · Gothenburg, SE

Key dates

• Filing date: Jun 15, 2020
• Grant date: Feb 22, 2022
• Expiry date: Jun 15, 2040

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/70
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for estimating a capacity of an electrical energy storage device with higher accuracy than what is provided in the prior art. The uncertainties in measured electrical current or voltage used in the estimation of the capacity of the electrical energy storage device are at least partly compensated for by using a bias compensated capacity estimator instead of the often-used prior art capacity estimator. The accuracy of the voltage and/or electric current sensor becomes of less importance which leads to that less complicated and less costly sensors may be used and to improve accuracy of the estimated energy storage capacity. The above advantages are obtained by providing a bias compensated capacity estimator that includes at least one bias term which is related to a deviation of an expected value of an original capacity estimator from a true capacity value.