Method and system for improved state estimation accuracy in battery management systems with cell balancing
US12399228B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Mar 7, 2022 |
| Grant date | Aug 26, 2025 |
| Priority date | — |
| Expiry date | Mar 7, 2042 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R27/16
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
When balancing cells in battery packs, the voltage induced by the balancing current across the parasitic wire resistance distorts the measured cell voltage, leading to inaccurate cell state estimation. A method and battery management system to extract a parasitic resistance of battery connection wires connecting a cell of a battery to a cell balancing circuit is disclosed. The parasitic wire resistances for a battery pack are extracted through the coordinated operation of a pack-level current source and cell-level balancing circuit. A voltage drop is imposed and measured across the parasitic resistances while maintaining zero current in the immediate battery cell. Maintaining zero current in the immediate battery cell avoids possible extraction error resulting from voltage drop across the battery cell impedance due to battery cell current flow.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.