Battery Pack Coupling Circuit With Current-Matched Load Strings
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Solution Overview
Problem
The increasing electrical voltage in battery packs due to the connection of multiple cells in series poses challenges for electrical units, requiring higher dielectric strength and increased costs, and results in uneven discharge of cells, affecting the battery's life and efficiency.
Innovation Solution
A device is coupled to a battery pack, dividing it into groups, using load units and sensor units to measure and control currents across different circuit strings, ensuring equal current flow through all cells, thereby balancing discharge and reducing the voltage applied to individual components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If multiple cells are connected in series to increase energy storage capacity, then the voltage between terminals increases, but the dielectric strength requirement and manufacturing costs increase
Solution Approach 1:
The battery pack is divided into multiple independent circuit strings, each handling a portion of the total voltage. The device segments the high-voltage system into lower-voltage subsystems that can be manufactured with standard dielectric strength components, reducing manufacturing costs while maintaining total energy storage capacity.
Solution Approach 2:
The patent changes the voltage distribution parameter by using multiple parallel circuit strings instead of a single series connection. This allows the same total voltage to be achieved through parallel combinations of lower-voltage segments, enabling the use of components with standard dielectric strength ratings and reducing manufacturing costs.
2Quantity of substance
If multiple cells are connected in series to increase energy storage capacity, then the voltage between terminals increases, but the dielectric strength requirement increases
Solution Approach 1:
The high-voltage battery pack is segmented into multiple parallel circuit strings, where each string operates at a lower voltage level. This segmentation allows the use of electrical components with standard dielectric strength ratings in each string, eliminating the need for expensive high-voltage resistant components while maintaining the overall high-voltage output through parallel combination.
Solution Approach 2:
The device acts as an intermediary by introducing multiple parallel circuit strings between the individual cells and the external load. Each circuit string serves as an intermediate pathway that distributes the voltage burden, allowing standard dielectric strength components to be used in each intermediate path while achieving the required total voltage through the parallel arrangement.
3Duration of action of stationary object
If cells are controlled to have equal voltage drop, then the battery pack service life is extended, but the device complexity increases
Solution Approach 1:
The circuit strings are designed to automatically balance the voltage distribution across cells through their inherent electrical characteristics. The equalization of voltage drops is achieved through the self-regulating nature of parallel circuit paths, eliminating the need for complex external control systems while extending battery pack service life through balanced cell operation.
Solution Approach 2:
The patent creates equipotential conditions across parallel circuit strings by designing them to have equal resistance characteristics. This causes the voltage to distribute evenly across all cells in each string, automatically achieving balanced cell operation and extended service life without requiring complex active control mechanisms.
4Ease of manufacture
If the voltage is reduced for individual components, then the manufacturing costs decrease, but the number of circuit strings increases
Solution Approach 1:
Multiple parallel circuit strings are merged into a single unified battery pack structure with common terminals. This merging approach allows each individual circuit string to use low-voltage components for cost-effective manufacturing, while the combined parallel structure delivers the required high-voltage output, effectively combining the benefits of low-cost components with high-voltage performance.
Data Source
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AI summary
The present disclosure relates to a device comprising: a first terminal, a second terminal, a third terminal, a first load unit, a first sensor unit, and a second load unit, wherein the device is configured to be coupled to a first group of cells of a battery via the first and second terminals, wherein the device is configured to be coupled to a second group of cells of a battery via the second and third terminals, wherein a first circuit string of the device extends between the first and second terminals, wherein the first load unit is integrated into the first circuit string, wherein the first sensor unit is configured to measure a first current in the first circuit string, wherein a second circuit string of the device extends between the second and third terminals, wherein the second load unit is integrated into the second circuit string, and wherein the device is configured to control the second load unit based on the first current such that the second load unit causes a second current in the second circuit string corresponding to the first current. The present disclosure also relates to a system comprising the device and the battery pack. Further, the present disclosure also relates to a method for the device.