LFP Positive Electrode Material With OCV Modifier for Accurate SOC
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium ferrum phosphoric acid (LFP) secondary batteries face challenges in accurately predicting state of charge (SOC) due to a flat open circuit voltage (OCV) profile, leading to high error rates, which complicates their application in vehicles where high-SOC or low-SOC regions are not used for durability.
Innovation Solution
Incorporating an OCV modifier into the positive electrode material of LFP secondary batteries, comprising a ternary active material, metal, or metal oxide that reacts with lithium in a specific potential region, to enhance the change in OCV with SOC, thereby improving prediction accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If LFP secondary battery uses flat OCV profile, then safety and fire resistance are improved, but SOC prediction accuracy deteriorates
Solution Approach 1:
The patent introduces an OCV modifier as an intermediary substance that mediates between the LFP active material and the electrolyte. This modifier has specific electrochemical properties that create additional OCV variation, allowing accurate SOC prediction while the main LFP material continues to provide safety and fire resistance
Solution Approach 2:
The patent creates a composite positive electrode material consisting of LFP active material combined with OCV modifier substances. This composite structure combines the safety advantages of LFP with the SOC prediction capabilities provided by the modifier, resolving the contradiction between safety and measurement accuracy
2Temperature
If LFP secondary battery uses flat OCV profile, then heat emission is reduced, but SOC prediction accuracy deteriorates
Solution Approach 1:
The OCV modifier acts as an intermediary that introduces measurable OCV changes without significantly increasing heat emission. The modifier's electrochemical reactions provide voltage variation signals for SOC prediction while maintaining the low heat emission characteristics of the LFP battery system
Solution Approach 2:
The patent changes the electrochemical parameters of the positive electrode by introducing OCV modifier substances with different potential characteristics. This creates additional OCV variation across the SOC range, enabling accurate SOC prediction while maintaining acceptable temperature and heat emission levels
3Measurement precision
If complex evaluation method is used for SOC prediction, then SOC prediction accuracy is improved, but device complexity increases
Solution Approach 1:
The patent changes the inherent OCV parameter characteristics of the battery by introducing OCV modifier materials. This transforms the flat OCV profile into a more variable profile, enabling accurate SOC prediction through simple OCV measurement without requiring complex evaluation methods or additional sensors
Solution Approach 2:
The OCV modifier enables the battery system to self-provide accurate SOC information through its natural OCV variations. This eliminates the need for external complex evaluation systems, current integration methods, or recalibration procedures, allowing the battery to accurately report its own SOC state
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
The addition of the OCV modifier allows for accurate SOC prediction, enhancing battery control and lifetime, while maintaining safety and reducing fire risks by limiting heat emission.
Implementation Method 1
an OCV modifier transforming the OCV... a ternary active material, an extended material of a ternary active material, an LMO-based active material, a metal that reacts with Li in a potential region of about 2.5 to 3.5 V vs. Li/Li+, and a metal oxide reacting with Li in a potential region of about 2.5 to 3.5 V vs. Li/Li+
Data Source
AI summary
Provided is a positive electrode material for a lithium secondary battery and the lithium secondary battery including the positive electrode material. The positive electrode material includes an open circuit voltage (OCV) modifier for changing an OCV to predict accurate state of charge (SOC) and state of health (SOH). A positive electrode material for a lithium (Li) secondary battery, which forms a positive electrode of the Li secondary battery, includes a main positive electrode material including a positive electrode active material formed of a lithium ferrum phosphoric acid (LFP) oxide, a conductive material, and a binder and an OCV modifier transforming the OCV.