Battery OCV Estimation from SOC-Specific Voltage Change Data
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for calculating open circuit voltage (OCV) of battery cells are time-consuming and resource-intensive, and they do not accurately diagnose the remaining lifetime of batteries due to reliance on direct measurement or charging/discharging experiments.
Innovation Solution
A battery data management apparatus that includes a communication module to receive battery data and a controller to generate SOC-specific voltage change information, calculate OCV, and smooth the data using interpolation and window filtering to estimate battery lifetime.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional direct measurement or charging/discharging experiments are used to calculate OCV, then measurement accuracy may be improved, but measurement time and resource consumption increase significantly
Solution Approach 1:
The system performs preliminary data collection and processing during normal battery operation, accumulating voltage and current data points before the actual OCV calculation is needed. This preliminary action eliminates the need for time-consuming charging/discharging experiments at the moment of measurement.
Solution Approach 2:
Instead of directly measuring OCV through physical experiments on the actual battery, the system creates a virtual model by processing existing voltage and current data to calculate OCV. This copying approach using mathematical models and data processing provides accurate OCV values without physical experimentation.
2Measurement precision
If conventional direct measurement or charging/discharging experiments are used to calculate OCV, then measurement accuracy may be improved, but resource consumption increases significantly
Solution Approach 1:
The system uses the battery's own operational data (voltage and current measurements taken during normal use) to calculate OCV, eliminating the need for external charging/discharging devices and associated resource consumption. The battery essentially measures itself using its own operational characteristics.
Solution Approach 2:
The system replaces resource-intensive physical experiments with computational processing of existing data. By creating a virtual representation of battery behavior through data processing, the system achieves accurate OCV measurement without consuming additional energy or resources.
3Ease of operation
If remaining capacity measurement alone is used to diagnose battery lifetime, then diagnostic simplicity is improved, but diagnostic accuracy deteriorates
Solution Approach 1:
The system segments the battery diagnosis process into multiple components: remaining capacity measurement, OCV calculation, and their combined analysis. By dividing the diagnostic approach into distinct parts that work together, the system maintains simplicity while significantly improving accuracy compared to using remaining capacity alone.
Solution Approach 2:
The system creates a composite diagnostic approach by combining remaining capacity measurement with OCV calculation results. This composite method integrates multiple measurement techniques to achieve accurate lifetime diagnosis while maintaining operational simplicity through automated processing.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A battery data management apparatus according to an embodiment disclosed herein includes a communication module configured to receive battery data from a vehicle and a controller configured to generate voltage change information with respect to state of charge (SOC)-specific charging/discharging rate (C-rate) by dividing the battery data based on an SOC range and generate open circuit voltage (OCV) change information with respect to an SOC by using the voltage change information with respect to the SOC-specific charging/discharging rate.