Battery Internal Short Detection Using Dual-Current Voltage Drop
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Internal short circuits in batteries can lead to safety issues such as battery failure, fire, or explosion, and existing methods lack accuracy in early detection and resistance calculation.
Innovation Solution
A method involving discharging the battery with two different currents, calculating corresponding voltage drops, and determining the presence of an internal short circuit based on the ratio of these voltage drops and currents, with further calculation of internal short-circuit resistance using an equivalent circuit model.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional single-current discharge method is used to detect internal short circuit, then the detection process is simple, but the detection accuracy is insufficient and cannot accurately determine internal short circuit presence
Solution Approach 1:
The detection method is segmented into multiple discrete steps: first discharge at current I1 to obtain voltage drop ΔV1, second discharge at current I2 to obtain voltage drop ΔV2, followed by separate ratio calculations (dVRatio = ΔV2/ΔV1 and dIRatio = I2/I1). This segmentation allows each measurement to be independently performed and compared, improving detection accuracy while maintaining procedural clarity
Solution Approach 2:
The method changes the discharge current parameter from a single fixed value to multiple different values (I1 and I2). By performing discharges at different current levels and comparing the resulting voltage drops, the system can detect non-linear voltage-current relationships that indicate internal short circuits, thereby improving measurement precision
2Measurement precision
If multiple discharge currents and ratio calculations are used to improve detection accuracy, then internal short circuit can be accurately detected, but the calculation process becomes more complex
Solution Approach 1:
The method uses feedback by comparing two calculated ratios (dVRatio and dIRatio) against each other. The comparison of these ratios provides feedback that confirms whether an internal short circuit is present, as the ratios should be equal in normal conditions but diverge when internal short circuit occurs. This feedback mechanism improves detection reliability
Solution Approach 2:
The voltage drop ratios and current ratios serve as intermediary variables that mediate between the raw measurements (voltages and currents) and the final detection conclusion. By introducing these intermediate calculation steps, the system transforms complex multi-parameter measurements into comparable ratio values that simplify the final comparison and decision-making process
3Manufacturing precision
If internal short-circuit resistance calculation is performed using equivalent circuit model, then the resistance value can be obtained for quantitative analysis, but the modeling and calculation process becomes more complex
Solution Approach 1:
The method creates a simplified equivalent circuit model that copies the essential electrical characteristics of the battery system without requiring the full complexity of the actual battery chemistry and physics. This equivalent model uses standard circuit elements (voltage sources, resistors) to represent the battery behavior under discharge conditions, enabling resistance calculation through straightforward circuit analysis while maintaining sufficient accuracy for detection purposes
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 method enables accurate and early detection of internal short circuits in batteries and calculates the internal short-circuit resistance, ensuring timely intervention and enhancing safety of electronic devices and users.
Implementation Method 1
discharging a battery with a first current I1 at a moment t1
Implementation Method 2
calculating a first discharge voltage drop ΔV1 of the battery at a moment t1+dt, where ΔV1=V0−V1
Data Source
AI summary
A method for detecting internal short circuit of a battery, includes: discharging a battery with a first current I1 at a moment t1; calculating a first discharge voltage drop ΔV1 of the battery at a moment t1+dt; discharging the battery with a second current I2 at a moment t2, where I1≠I2; calculating a second discharge voltage drop ΔV2 of the battery at a moment t2+dt; and determining, based on the first current I1, the first discharge voltage drop ΔV1, the second current I2, and the second discharge voltage drop ΔV2, whether the battery has an internal short circuit. In this application, whether the battery has an internal short circuit can be accurately determined, thereby ensuring safety of an electronic apparatus and a user.