Fast screening method for used batteries using constant-current impulse ratio (CCIR) calibration

US11656291B2 · kind B2 · utility

Assignee

• Hong Kong Applied Science and Technology Research Institute Company Limited · CN

Inventors

• Minjie Xu
• Liya Zheng · Hong Kong, CN
• Yaofeng Sun · Sha Tin, CN

Key dates

• Filing date: Feb 8, 2021
• Grant date: May 23, 2023
• Expiry date: Jan 22, 2042

Classification

• Technology area (CPC H): Electricity
• CPC primary: H02J7/007
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Used batteries are screened based on a measured Constant-Current Impulse Ratio. A used battery is charged using a Constant Current (CC) until a voltage target is reached, and the current integrated to obtain the CC charge applied, QCC. Then the battery continues to be charged using a Constant Voltage (CV) of the voltage target until the charging current falls to a minimum current target. The current is integrated over the CV period to obtain the CV charge applied, QCV. The measured CCIR is the ratio of QCC to (QCC+QCV). The measured CCIR is input to a calibration curve function to obtain a modeled State of Health (SOH) value. The used battery is sorted for reuse or disposal based on the modeled SOH value. The calibration curve function is obtained by aging new batteries to obtain CCIR and SOH data that are modeled using a neural network.