Battery Cell Impedance Charging Control for Fast Charge Safety
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional techniques struggle to optimize the charging time of power storage devices, particularly in quick charging scenarios, as they do not effectively account for the deterioration and temperature variations of individual cells within a battery pack.
Innovation Solution
A power storage system and method that utilizes a complex impedance measuring unit to determine the charging current based on the deterioration and temperature of each cell, optimizing the charging process by using an alternating current excitation and controlling the charging current accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional charging techniques are used, then the charging process is simple, but the charging time cannot be optimized and safety is compromised due to inability to account for individual cell deterioration
Solution Approach 1:
The patent divides the battery pack into individual cell units, measuring complex impedance for each cell separately to detect deterioration states. This segmentation allows targeted charging control for each cell based on its specific condition, improving safety while managing complexity through modular measurement and control approaches.
Solution Approach 2:
The patent changes the charging control parameters dynamically based on measured complex impedance values and detected deterioration states. By adjusting charging current and voltage parameters according to real-time cell conditions, the system optimizes charging safety and efficiency without requiring overly complex hardware architecture.
2Loss of time
If quick charging is implemented with high charging current, then charging time is reduced, but cell deterioration and overheating risks increase
Solution Approach 1:
The patent implements a feedback mechanism where complex impedance is measured during charging, and the charging current is adjusted based on the measured values and detected deterioration states. This closed-loop control allows the system to maintain high charging currents when cells are healthy while reducing current when deterioration is detected, optimizing charging speed while preventing damage.
Solution Approach 2:
The charging current is made dynamic rather than fixed, adjusting in real-time based on cell condition. The system transitions between different charging phases and current levels according to measured impedance changes and deterioration detection, enabling safe quick charging by adapting to instantaneous cell states.
3Measurement precision
If individual cell monitoring is implemented, then charging safety and optimization are improved, but measurement and control complexity increases
Solution Approach 1:
The patent uses a universal complex impedance measurement approach that can be applied to each cell using the same measurement circuit and methodology. This multi-functional measurement system detects both deterioration states and provides data for charging control, reducing overall system complexity by using a single versatile measurement technique rather than multiple specialized sensors.
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 allows for efficient optimization of charging time, ensuring safe and rapid charging by considering the individual state of each cell, thereby reducing the charging time while preventing overheating.
Implementation Method 1
an alternating current excitating circuit that excitates the charging current using an alternating current
Implementation Method 2
a complex impedance measuring unit that measures a current value of the alternating current used to excitate the charging current and a voltage value of each of the plurality of power storage cells, and measures a complex impedance of each of the plurality of power storage cells from the measured current value and the measured voltage value
Data Source
Figure 1
Figure 2
Figure 3(a)~3(c)
AI summary
A power storage system (1) includes: a power storage device (100) including a cell stack (101) including power storage cells (B0 to B5) connected in series; and a charging device (200) that supplies a charging current to the power storage device (100). The power storage system (1) further includes: an alternating current excitating circuit (148) in the power storage device (100) or the charging device (200) that excitates the charging current using an alternating current; a complex impedance measuring unit (110) in the power storage device (100) that measures a current value of the alternating current used to excitate the charging current and a voltage value of each of the power storage cells (B0 to B5), and measures a complex impedance of each of the power storage cells (B0 to B5) from the measured current and voltage values; and a charging control unit in the power storage device (100) or the charging device (200) that controls the charging current based on the complex impedance.