Battery Control Unit Current Measurement via Voltage Monitoring IC
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing battery control systems require two current sensors, increasing size and complexity, and necessitate separate power supplies and A/D converters due to different architectures, which complicates the arrangement and increases costs.
Innovation Solution
The system uses a cell voltage monitoring IC to measure battery voltage, eliminating the need for a current sensor by employing a resistor (bus bar) connected in series with the battery cells and cell voltage detection lines to calculate current flow, reducing the number of sensors and simplifying the system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If two current sensors are used to measure battery current, then current measurement accuracy is improved, but system size and complexity increase
Solution Approach 1:
The patent combines the current measurement function with the existing cell voltage monitoring IC by adding a current detection terminal. This merging eliminates the need for separate current sensors while maintaining measurement capability, directly resolving the contradiction between measurement accuracy and system complexity
Solution Approach 2:
The cell voltage monitoring IC is enhanced to perform both voltage monitoring and current measurement functions. By making the IC multi-functional, the system eliminates dedicated current sensors, thereby reducing device complexity while preserving measurement precision through the existing high-precision IC
2Reliability
If two current sensors with different architectures are used, then current measurement reliability is improved, but power supply and A/D converter systems must be separated increasing complexity
Solution Approach 1:
The patent merges the current detection function into the existing voltage monitoring IC architecture, allowing both voltage and current measurements to share the same power supply and A/D converter systems. This eliminates the need for separate power supply systems while maintaining measurement reliability through the proven IC platform
3Measurement precision
If two Hall ICs are provided in a gap of one magnetic core, then current measurement accuracy is improved, but arrangement space is reduced
Solution Approach 1:
The patent extracts the current measurement function from the physical current sensor hardware and integrates it into the electrical circuitry of the existing voltage monitoring IC. This extraction eliminates the need for magnetic cores and Hall ICs, thereby freeing up significant arrangement space while preserving measurement precision through electronic measurement
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 current measurement without additional current sensors, reducing system size, cost, and improving accuracy, while enabling failure diagnosis and protection against overcharge/discharge in lithium ion batteries.
Implementation Method 1
a battery controller 210 connected to the cell voltage detection lines 101 to 104, in which one cell voltage detection line 101 to 104 adjacent to the battery cell 11 or 12 includes a terminal which is branched and connected to the battery controller
Data Source
AI summary
The invention is directed to provide a battery pack in which a current sensor is eliminated and the whole size is reduced. In order to solve the problem described above, a battery pack of the invention includes a battery group in which a plurality of battery cells (lithium ion battery 11, 12) are connected in series, a resistor (bus bar 20) connected in series to the battery group, cell voltage detection lines (cell voltage detection lines 101 to 104) arranged at both ends of the battery cells (lithium ion battery 11, 12) and the resistor (bus bar 20), and a battery controller connected to the cell voltage detection lines (cell voltage detection lines 101 to 104), in which one cell voltage detection line (cell voltage detection lines 101 to 104) adjacent to the battery cell (lithium ion battery 11, 12) includes a terminal which is branched and connected to the battery controller.