Battery Deplating Controller for Lithium Plating Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium-ion batteries in electrified vehicles experience lithium plating when charged with currents exceeding design limits, leading to decreased capacity and increased cell resistance, potentially requiring battery replacement.
Innovation Solution
A method involving a controller that inhibits further charging and discharges the battery at a predetermined current for a defined duration to remove lithium from the anode, utilizing existing vehicle components like DC/DC converters and passive balance switches, and HVAC systems to manage the discharge process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If charge current exceeds design limit to increase charging speed, then productivity is improved, but lithium plating occurs on the anode causing battery capacity loss and increased cell resistance
Solution Approach 1:
The controller performs preliminary detection of charge current magnitude and duration before lithium plating occurs. When the charge current exceeds the threshold, the controller proactively commands a deplating discharge operation to remove plated lithium ions from the anode surface before they cause permanent capacity loss or resistance increase.
Solution Approach 2:
The invention converts the harmful effect of lithium plating into a beneficial process by using controlled deplating discharge. The plated lithium ions that would normally degrade battery performance are instead utilized as a source of discharge current, and the deplating process itself removes the harmful deposits while recovering capacity.
2Productivity
If charge current exceeds design limit to increase charging speed, then productivity is improved, but cell resistance increases due to lithium plating
Solution Approach 1:
The controller detects charge current parameters in advance and commands deplating discharge operations before resistance significantly increases. This preliminary action prevents the accumulation of lithium plating that would otherwise cause irreversible resistance increase.
Solution Approach 2:
The system implements feedback control by continuously monitoring charge current magnitude and duration, comparing against predefined thresholds, and automatically adjusting battery operations by commanding deplating discharge when thresholds are exceeded, thereby maintaining low cell resistance.
3Reliability
If deplating discharge is commanded to remove lithium plating, then battery capacity is restored, but additional time is required beyond normal charging cycle
Solution Approach 1:
The deplating discharge operation converts harmful lithium plating into useful discharge current. Instead of wasting time removing plating through idle processes, the system utilizes the plated lithium ions themselves as the discharge source, making the remediation process productive rather than purely corrective.
Solution Approach 2:
The invention merges the charging and deplating operations into a single integrated cycle. The deplating discharge is commanded immediately following high-current charging without requiring separate remediation time, effectively combining what would traditionally be two distinct operations into one continuous process.
4Reliability
If controller monitors charge current and commands deplating discharge to prevent lithium plating, then battery reliability is improved, but device complexity increases
Solution Approach 1:
The controller implements feedback control by monitoring charge current parameters, comparing them against predefined thresholds related to lithium plating occurrence, and automatically commanding deplating discharge operations when thresholds are exceeded. This closed-loop control maintains battery reliability through automated detection and correction.
Solution Approach 2:
The battery system performs self-service by using its own existing components (DC-DC converter, passive balance switch) to execute deplating discharge operations. The controller leverages already-present hardware resources rather than requiring additional dedicated deplating equipment, thereby maintaining reliability while minimizing complexity increase.
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
Effectively removes lithium plating, reducing battery aging and cell resistance, allowing safe vehicle operation and extending battery life by using existing components to manage and control the discharge process.
Implementation Method 1
discharging the battery for a predetermined time at a predetermined current both defined by an amount and duration that the charge current exceeded the threshold to deplate lithium from an anode of the battery
Data Source
AI summary
A method for a vehicle comprises, by a controller, responsive to charge current for a battery exceeding a threshold, inhibiting further charging of the battery. The method further includes, responsive to the vehicle achieving a predefined state following the charge current exceeding the threshold, discharging the battery for a predetermined time at a predetermined current both defined by an amount and duration that the charge current exceeded the threshold to deplate lithium from an anode of the battery.