Semiconductor Device for Battery Short Circuit Detection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing battery state monitoring systems struggle to detect short circuits between terminals coupled with current detecting resistances having small resistance values, leading to erroneous measurements and operational issues in vehicle systems.

Innovation Solution

A semiconductor device with a control circuit that measures voltage differences between external terminals coupled to a current detecting resistance, employing a short-circuit test operation to detect and differentiate voltage changes caused by short circuits, utilizing two current sources and switching circuits to facilitate accurate detection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a current detecting resistance with a small resistance value is used to measure current flowing through the battery, then the measurement range and applicability are improved, but the ability to detect short circuit states deteriorates because the resistance value becomes too close to wiring resistance

Engineering Contradiction:

Improvemeasurement rangeVSAvoidshort circuit detection ability

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The system performs a short circuit test operation before normal current measurement to preliminarily identify and flag potential short circuit conditions. This preliminary action allows the system to prepare appropriate response measures and prevents erroneous measurements from occurring during normal operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The short circuit detection is performed periodically through dedicated test operations where the current detecting resistance is selectively connected to different terminals. This periodic testing approach enables continuous monitoring of short circuit conditions while maintaining normal measurement functionality between tests.

Inventive Principle:

Principle #19Periodic action

2Measurement precision

If a voltage measurement system based on battery cell voltage is used, then the system can monitor battery state, but it is incapable of detecting short circuits between terminals coupled with current detecting resistance

Engineering Contradiction:

Improvebattery state measurementVSAvoidshort circuit detection capability

Core Design Contradiction:

Measurement precisionVSDifficulty of detecting and measuring

Solution Approach 1:

The measurement system is designed to perform multiple functions: normal current measurement through the current detecting resistance, short circuit detection through selective terminal connections, and battery state monitoring. This multi-functional approach eliminates the need for separate detection systems while maintaining comprehensive monitoring capability.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The control circuit acts as an intermediary that selectively connects the current detecting resistance to different terminals based on the operational mode. During short circuit tests, it connects the resistance to specific terminal combinations to induce detectable voltage changes, while during normal operation it connects to the standard current measurement path.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Loss of energy

If the resistance value of current detecting resistance is made very small to reduce power loss, then energy efficiency is improved, but the voltage difference signal becomes too small to reliably detect short circuits

Engineering Contradiction:

Improvepower lossVSAvoidvoltage difference detection

Core Design Contradiction:

Loss of energyVSMeasurement precision

Solution Approach 1:

The system dynamically switches between different measurement modes: normal current measurement mode with small resistance for low power loss, and short circuit test mode with selective terminal connections for enhanced detection sensitivity. This dynamic approach allows the system to optimize for energy efficiency during operation while maintaining detection capability when needed.

Inventive Principle:

Principle #15Dynamics

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

Enables reliable detection of short circuits between terminals with small resistance values, improving measurement accuracy and preventing operational failures in vehicle systems by distinguishing voltage differences in short-circuit test operations.

Implementation Method 1

measures a voltage difference between the first external terminal and the second external terminal

Methodology Applied

Scientific EffectOhm's Law: Ohm's Law

Data Source

PatentUS9933490B2Semiconductor device, battery state monitoring module, and vehicle system

Publication Date: 2018.04.03 RENESAS ELECTRONICS CORP

AI summary

A vehicle system, includes a battery state monitoring module including a battery state monitoring device for measuring a current monitor voltage value that varies according to a current value flowing through a current detecting resistance coupled to power supply terminals of a battery, and an arithmetic circuit that determines a state of the battery based on the current monitor voltage value measured by the battery state monitoring device and transmits the determination result at a request from a high-order system, and a central control unit for outputting an internal ignition signal that directs start and stop of a engine to an electronic load circuit for controlling the engine and a starter, the battery state monitoring device carries out a short-circuit test operation for testing a short circuit state between two external terminals coupled to two ends of the current detecting resistance, and a current monitoring operation of measuring.