Battery State Determination via Segmented Estimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional battery state determining devices fail to accurately assess the degradation state of storage batteries experiencing two types of degradation modes, such as corroded collectors and sulfation, leading to decreased accuracy in determining the State of Health (SOH).
Innovation Solution
A battery state determining device that includes a voltage measuring part, remaining capacity estimating part, internal resistance measuring part, and calculating part, which estimates the degradation state by using open-circuit voltage, internal resistance, and regression analysis data to differentiate between the two degradation modes, providing a more accurate estimation through first and second estimation processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional degradation state calculation methods are used, then the device complexity is low, but the measurement precision of degradation state is insufficient when two types of degradation modes are present
Solution Approach 1:
The patent segments the degradation state estimation into two distinct components: first estimation based on remaining capacity and internal resistance degradation rate, and second estimation that corrects the first estimation using the relationship between open-circuit voltage and remaining capacity. This segmentation allows each estimation method to address specific aspects of battery degradation, improving overall accuracy while maintaining manageable complexity through structured multi-step processing
2Reliability
If single estimation method based on internal resistance is used, then the calculation process is simple, but the reliability of degradation state determination decreases when multiple degradation modes exist
Solution Approach 1:
The patent introduces an intermediary correction mechanism where the open-circuit voltage serves as a mediator to verify and adjust the first estimation result. The second estimation uses the open-circuit voltage to determine remaining capacity, which then corrects the first estimation to account for sulfation effects that internal resistance alone cannot detect, thereby improving reliability without requiring completely new measurement systems
3Measurement precision
If conventional single-parameter estimation is used, then the ease of operation is high, but the measurement precision decreases for batteries with fluctuating loads
Solution Approach 1:
The patent performs preliminary measurements of open-circuit voltage, internal resistance, and remaining capacity before conducting the degradation state estimation. These preliminary actions establish baseline data that enable the two-stage estimation process to accurately differentiate between corrosion and sulfation effects, ensuring high measurement precision even under fluctuating load conditions while maintaining operational simplicity through automated sequential processing
Data Source
AI summary
A battery state determining device includes a voltage measuring part, a remaining capacity estimating part, an internal resistance measuring part, a calculating part, and an estimating part. The voltage measuring part measures an open-circuit voltage of a storage battery. Based on the measured open-circuit voltage, the remaining capacity estimating part estimates a remaining capacity of the storage battery. The internal resistance measuring part measures an internal resistance in the storage battery. Based on the measured internal resistance, the calculating part calculates a degradation rate of the internal resistance. Based on the estimated remaining capacity and the calculated degradation rate of the internal resistance, the estimating part performs first estimation on a degradation state of the storage battery.