Battery Available Capacity Estimation Using Recoverable Fade Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for estimating the available capacity of batteries cannot accurately distinguish between unrecoverable and recoverable capacity fade, leading to inaccurate estimation of residual capacity and aging state.
Innovation Solution
A method and device that determine the available capacity of a battery by obtaining SOC and DOD intervals, cycle number, and temperature, calculating the recoverable amount of capacity fade, and adjusting the actual available capacity based on this information, with the option to eliminate recoverable fade through full charge and discharge cycles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If current estimation methods (offline capacity test with aging curve or online OCV-SOC curve) are used, then the estimation process is simple, but the measurement precision of available capacity is insufficient due to inability to distinguish unrecoverable and recoverable capacity fade
Solution Approach 1:
The patent segments capacity fade into two distinct components: unrecoverable capacity fade (permanent degradation) and recoverable capacity fade (temporary effects like memory effect). By separately tracking and estimating these two components through different methodologies, the system achieves more precise available capacity estimation while maintaining manageable complexity through modular processing of each fade type.
2Measurement precision
If current methods calculate only the sum of unrecoverable and recoverable capacity fade, then the calculation process is simple, but the measurement precision of available capacity is insufficient
Solution Approach 1:
The estimation process is segmented into separate calculation streams for unrecoverable capacity fade (based on cycle number and temperature) and recoverable capacity fade (based on SOC intervals and discharge depth). This segmentation enables parallel processing of different fade mechanisms, maintaining computational efficiency while significantly improving measurement precision through differentiated analysis of each fade type.
Solution Approach 2:
The patent employs different parameter sets for estimating different fade types: unrecoverable fade uses cycle number and temperature parameters, while recoverable fade uses SOC intervals and discharge depth parameters. This parameter differentiation allows the system to capture the unique characteristics of each fade mechanism, improving estimation accuracy without requiring a single complex unified model.
Data Source
AI summary
A method and device for determining an available capacity of a battery, a battery management system, and a storage medium, relating to the field of battery technologies. The method includes: obtaining the at least one DOD interval corresponding to the SOC interval of the operation of the battery, and the number of cycles and the cycle temperature corresponding to the at least one DOD interval; obtaining a recoverable amount of capacity fade of the battery according to the at least one DOD interval, the number of cycles and the cycle temperature, and determining an actual available capacity of the battery.