Open-Circuit Voltage Estimation via Polarization Component Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing open-circuit voltage estimation techniques lack precision, particularly in environments with varying temperatures and loads, leading to inaccuracies in estimating the open-circuit voltage value of secondary cells.
Innovation Solution
An open-circuit voltage estimation device comprising an open-circuit voltage calculator, a polarization voltage estimator, and an open-circuit voltage corrector, which calculates and corrects the open-circuit voltage value by estimating and accounting for the slow polarization voltage component with a relatively large time constant, using average values of current and cell temperature, and referencing pre-acquired correspondence tables.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional open-circuit voltage estimation techniques are used, then the estimation process is simple, but the estimation precision is low
Solution Approach 1:
The invention segments the polarization voltage into multiple components with different time constants (fast component and slow component). By separating and independently estimating each component, the system achieves more precise open-circuit voltage estimation while managing complexity through modular estimation approaches for each polarization component
Solution Approach 2:
The invention performs preliminary estimation of polarization voltage components before calculating the final open-circuit voltage. By pre-estimating the fast and slow polarization components and their time constants, the system prepares correction values in advance that improve the overall estimation precision without adding significant operational complexity
2Measurement precision
If polarization voltage components are not considered, then the estimation device is simple, but the estimation accuracy deteriorates under varying temperatures and loads
Solution Approach 1:
The invention dynamically adapts the estimation process to varying temperatures and loads by separately estimating fast and slow polarization voltage components. The system adjusts its estimation behavior based on operating conditions, with each polarization component being estimated according to its specific time constant characteristics under different temperature and load scenarios
Solution Approach 2:
The invention changes the estimation parameters by introducing time constant-based component separation. By estimating polarization voltages as functions of their respective time constants (fast and slow components), the system adapts to varying operating conditions while maintaining high estimation precision across different temperatures and loads
Data Source
AI summary
The present disclosure provides an open-circuit voltage estimation device that estimates a high-precision open-circuit voltage value, a power storage apparatus, and an open-circuit voltage estimation method. The open-circuit voltage estimation device includes: an open-circuit voltage calculator that calculates an open-circuit voltage value of a secondary cell; a polarization voltage estimator that estimates a component having a relatively large time constant among polarization voltage components of the secondary cell; and an open-circuit voltage corrector that corrects the open-circuit voltage value calculated by the open-circuit voltage calculator with the component having the relatively large time constant estimated by the polarization voltage estimator.