Battery Equalization Circuit Using Switch Matrix and Dual Units

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing battery systems face complexity in their equalization circuits due to the need for complex driving apparatuses to manage voltage differences among battery cells, leading to inefficiencies and increased costs.

Innovation Solution

A control circuit apparatus with a switch matrix network and parallel equalization units that utilize resistors and transformers to simplify the equalization process by reducing the need for complex components and driving solutions, enabling efficient voltage equalization through resistor discharge and power supply charging.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a traditional equalization circuit is used to equalize battery cell voltages, then voltage equalization can be achieved, but the driving apparatus becomes complex

Engineering Contradiction:
Improvevoltage equalization capabilityVSAvoiddriving apparatus complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The equalization circuit is segmented into two independent units: a first equalization unit for discharging high-voltage cells and a second equalization unit for charging low-voltage cells. Each unit has its own simplified driving circuit, avoiding the need for a single complex bidirectional driving apparatus. The switch matrix network separately controls each unit based on cell voltage status.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The first equalization unit and second equalization unit are combined in a parallel configuration within the same control circuit apparatus, sharing common components like the switch matrix network and control unit. This merging reduces overall system complexity while maintaining independent simplified driving circuits for each equalization function.

Inventive Principle:
Principle #5Merging (Combining)

2Measurement precision

If complex driving apparatus is used to control equalization circuit, then precise voltage control can be achieved, but component count and cost increase

Engineering Contradiction:
Improvevoltage control precisionVSAvoidcomponent count
Core Design Contradiction:
Measurement precisionVSQuantity of substance

Solution Approach 1:

The control system is segmented into two independent driving circuits, each dedicated to one equalization function. This segmentation allows each driving circuit to be optimized for its specific function with fewer components, while the control unit uses voltage sampling to precisely determine which cells need equalization and directs them to the appropriate unit.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The control unit acts as an intermediary that samples battery cell voltages, determines which cells require equalization, and controls the switch matrix network to connect the appropriate cells to the corresponding equalization unit. This intermediary approach enables precise voltage control through simple switching operations rather than complex continuous control circuits.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If traditional equalization method is used, then voltage equalization can be achieved, but circuit structure becomes complex

Engineering Contradiction:
Improvevoltage equalization functionVSAvoidcircuit structure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The equalization function is segmented into two separate units with dedicated simple circuits: the first unit uses a resistor for discharge equalization and the second unit uses a power supply for charge equalization. This segmentation eliminates the need for complex bidirectional energy transfer circuits, significantly simplifying the overall circuit structure while maintaining effective voltage equalization.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The first equalization unit uses a resistor for discharge equalization, which is a simple, inexpensive component that converts excess energy to heat. This approach trades energy efficiency for circuit simplicity, using a basic passive component instead of complex active circuitry to achieve the equalization function.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

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

The solution simplifies the circuit structure, reduces component count, and lowers costs while effectively equalizing battery voltages, enhancing the reliability and efficiency of battery systems.

Implementation Method 1

The first equalization unit is configured to discharge the to-be-discharged battery unit through a resistor unit

Methodology Applied
Scientific EffectJoule heating: Joule Heating

Implementation Method 2

The second equalization unit is configured to charge the to-be-charged battery unit through the power supply

Methodology Applied
Scientific EffectElectrical energy transfer: Conduction (electrical)

Data Source

PatentEP4277078B1Control circuit apparatus of battery system and battery management system
Publication Date: 2025.08.27 HUAWEI DIGITAL POWER TECH CO LTD
  • EP4277078B1 patent drawingFigure 1
  • EP4277078B1 patent drawingFigure 2
  • EP4277078B1 patent drawingFigure 3

AI summary

This application provides a control circuit apparatus (300) of a battery system and a battery management system, and is applied to the field of battery equalization technologies. The control circuit apparatus (300) in this application includes a switch matrix network unit (301), a first equalization unit (3022), and a second equalization unit (3021). The switch matrix network unit (301) is configured to: form a loop between m battery units in the battery system and the first equalization unit (3022), and form a loop between the m battery units in the battery system and the second equalization unit (3021). The first equalization unit (3022) discharges a high-voltage battery unit through a resistor unit, and the second equalization (3021) unit charges a low-voltage battery unit through a transformer. In technical solutions of this application, because an MOS transistor of the second equalization unit (3021) is easier to drive compared with an MOS transistor of a bidirectional equalization circuit in the conventional technology, complexity of a driving apparatus of the MOS transistor of the equalization circuit of the battery system may be reduced.