Discharge Control Device for Secondary Battery Pulse Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Secondary batteries, such as lithium ion batteries, deteriorate due to excessive charging, which leads to lithium metal deposition on the anode surface, causing a decrease in full charge capacity, often resulting from excessive current pulses during slip events in hybrid or electric vehicles.
Innovation Solution
A discharge control device that detects excessive charging pulses and controls a discharge with pulses of identical electric energy and duration to prevent lithium metal deposition, using a motor connected to the battery and applying phase control to manage the discharge.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If charging is performed by excessive current pulse when grip is restored after slip, then the battery can be quickly recharged, but lithium metal deposits on the anode surface causing battery deterioration
Solution Approach 1:
The patent converts the harmful excessive charging pulse into a beneficial process by intentionally inducing controlled lithium metal deposition followed by a recovery phase. The system applies a large current pulse that would normally cause damage, but then follows it with a smaller current pulse or rest period that allows the lithium to redistribute and the electrode to recover, thereby transforming the harmful effect into a useful activation process that maintains battery performance.
Solution Approach 2:
The patent implements periodic charging/discharging cycles to alternately repeat charging and discharging. This periodic action prevents continuous excessive charging by introducing rest periods or reverse polarity pulses, allowing the battery electrode to recover from lithium deposition and maintain its activation state, thus preventing cumulative damage while still enabling quick charging when needed.
2Quantity of substance
If constant-voltage charging is carried out, then the battery can be fully charged, but the charging process takes excessive time
Solution Approach 1:
The patent employs periodic charging/discharging cycles that alternate between charging and discharging phases. This periodic action enables the battery to reach full charge capacity more quickly by utilizing the discharge phase to redistribute lithium ions and activate electrodes, thereby reducing the total time required to achieve full charging compared to continuous constant-voltage charging.
Solution Approach 2:
The patent maintains continuous useful action by alternating charging and discharging operations. Rather than stopping after charging, the system immediately follows with a discharge phase that continues the electrochemical activation process, ensuring that the battery remains in a state of useful electrochemical activity throughout the entire cycle, thereby reducing idle time and accelerating the overall charging process.
Data Source
Figure 1
Figure 2~3
Figure 4~6
AI summary
The object aims to prevent or reduce the deterioration of a secondary battery by charge with an undue pulse. Disclosed is a discharge control device (100) for a secondary battery, which comprises: a detection unit (110) for detecting the charge of the secondary battery with a pulse having a level equal to or higher than a predetermined level; and a discharge control unit (130) for so controlling that at least one pulse having almost the same level as that of the above-mentioned pulse is discharged from the secondary battery when the charge of the secondary battery with the above-mentioned pulse is detected.