Battery Power Limit Estimation Using Fleet-Based Aging Profiles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for determining power and current limits for propulsion batteries in vehicles often lead to conservative or overestimated values due to the assumption of constant power output, which does not reflect real-world usage patterns.
Innovation Solution
A method that utilizes vehicle fleet data to categorize power usage profiles and calculate a time-dependent averaged current profile, which is applied to electrical energy storage cells to realistically age them and determine accurate power or current limits based on expected driving behavior.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a flat C-rate aging process with constant power output is used to determine battery limits, then the process is simple and straightforward, but the resulting power limits are conservative or overestimated and do not reflect real-world usage
Solution Approach 1:
The patent applies preliminary action by using real-world fleet data to pre-calculate representative current profiles before the aging process. These profiles capture actual usage patterns and are then applied during battery aging to determine accurate power limits, avoiding the need for complex real-time monitoring during testing while maintaining high accuracy
Solution Approach 2:
The patent uses copying by creating simplified current profiles that replicate real-world usage patterns observed from fleet data. Instead of directly using complex real-world data during aging, the patent creates representative copies (current profiles) that capture essential usage characteristics, making the aging process both accurate and manageable
2Reliability
If real-world variable power usage patterns are applied to age the battery, then the power limit estimation becomes more accurate, but the aging process and data requirements become more complex
Solution Approach 1:
The patent applies taking out by extracting essential usage patterns from large volumes of complex fleet data. Instead of using all raw real-world data during aging, the patent extracts key characteristics (current profiles representing different usage levels) that capture the essential variability of real-world usage, reducing data complexity while maintaining aging realism
Solution Approach 2:
The patent uses parameter changes by transforming raw fleet data into standardized current profiles with specific parameters (e.g., current levels, duration, cycles). This transformation changes the data from complex raw measurements into structured parameters that can be systematically applied during aging, balancing realism with manageability
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
The invention relates to a method for estimating a power or current limit for an electrical energy storage system (2), the method comprising: obtaining (S102) vehicle fleet data indicating power usage of a fleet (4) of vehicles (1) in a geographical area (6); categorizing (S104) the vehicle fleet data into a set of power usage profiles (10, 20, 30) depending on an expected amount of power usage determined from the vehicle fleet data; calculating (S106) a time dependent averaged current profile (12) from a distribution of the power usage profiles; and applying (S108) the time dependent averaged current profile (12) to an electrical energy storage cell (3) to age the electrical energy storage cell to a predetermined state of health, and determining (S110) the power or current limit (14) for the electrical energy storage cell.