Battery Parameter Estimation Under Low Diffusion Length Conditions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing Single Particle Models (SPM) for state of charge (SOC) estimation in batteries are inaccurate under low diffusivity conditions, leading to errors in SOC estimation, which can cause over-discharge, accelerated aging, and short circuits due to invalid profile approximations at low temperatures and initial times.
Innovation Solution
A method and electronic device that determine the diffusion length of intercalation material in a battery electrode, calculate its concentration based on specific parameters, and estimate battery parameters such as SOC, state of health, or electrochemical parameters using a processor, employing techniques like similarity variables and open circuit voltage profiles to improve accuracy under low diffusivity conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If Single Particle Models (SPM) are used for SOC estimation, then computational efficiency and speed are improved, but measurement precision deteriorates under low diffusivity conditions
Solution Approach 1:
The patent dynamically switches between different estimation models based on diffusion length conditions. When diffusion length is below the threshold, the system transitions from standard SPM to the improved model using similarity variables, ensuring accuracy adapts to changing operational conditions while maintaining computational efficiency through conditional logic rather than always using the more complex model
Solution Approach 2:
The patent changes the mathematical parameters and variables used in the estimation model based on diffusion length conditions. By introducing similarity variables and modifying the concentration calculation approach when diffusion length is low, the system maintains measurement precision across different operational regimes without sacrificing the computational efficiency of the underlying model structure
2Device complexity
If profile approximations are used in SPM, then computational complexity is reduced, but measurement precision deteriorates at low temperatures and initial times
Solution Approach 1:
The patent applies different calculation approaches in different operational regions. When diffusion length is below the threshold (low temperatures/initial times), it uses the improved method with similarity variables and explicit concentration calculations, while allowing standard approximations to suffice when diffusion length is adequate, thus optimizing the balance between complexity and precision for each specific condition
3Speed
If standard SPM is used under low diffusion lengths, then computational speed is maintained, but reliability deteriorates due to accumulated SOC errors
Solution Approach 1:
The patent implements a feedback mechanism where the diffusion length is continuously monitored and compared against a threshold. Based on this feedback, the system automatically selects the appropriate estimation method, ensuring reliability is maintained by using the improved model when low diffusion conditions are detected, while preserving computational speed through efficient conditional branching
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach provides more accurate SOC estimation and state of health assessment in low diffusivity conditions, reducing errors and safety issues like over-discharge and short circuits, thereby enhancing battery management and safety.
Implementation Method 1
determining whether a diffusion length of an intercalation material in an electrode of a battery is lesser than a threshold, calculating a concentration of the intercalation material in the electrode based on a result of the determination
Data Source
Figure 1A
Figure 1B
Figure 1C
AI summary
Methods and an electronic devices for estimating battery parameters, where the method of estimating battery parameters performed by a processor includes determining whether a diffusion length of an intercalation material in an electrode of a battery is lesser than a threshold, calculating a concentration of the intercalation material in the electrode based on a result of the determination, and estimating at least one battery parameter of the battery parameters based on the concentration of the intercalation material.