Pyrotechnic Battery Disconnect Circuit for Thermal Runaway Isolation

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Solution Overview

Problem

Existing mechanical switches for energy storage units in high voltage systems are bulky and costly, making them unsuitable for efficient disconnection during safety events like thermal runaway or overvoltage.

Innovation Solution

Employing pyrotechnic switches with a control unit to manage the connection and disconnection of energy storage units, utilizing pyrotechnic charges for rapid and compact switching, allowing for adjustable time delays in switching sequences.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If multiple separate battery modules are used to increase energy storage capacity, then the energy storage capacity is improved, but the system complexity and space requirements increase

Engineering Contradiction:
Improveenergy storage capacityVSAvoidsystem complexity
Core Design Contradiction:
Quantity of substanceVSDevice complexity

Solution Approach 1:

The patent combines multiple battery modules into a single integrated battery pack structure. The battery pack housing encloses multiple battery modules, controllers, and thermal management components in one unified assembly, reducing the number of separate components and simplifying the overall system architecture while maintaining high energy storage capacity.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The battery pack housing serves multiple functions simultaneously: it provides structural support, thermal management pathways, electrical isolation, and mechanical protection. This multi-functionality reduces the need for separate dedicated components for each function, thereby reducing system complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Quantity of substance

If multiple separate battery modules are used to increase energy storage capacity, then the energy storage capacity is improved, but the space occupation increases

Engineering Contradiction:
Improveenergy storage capacityVSAvoidspace occupation
Core Design Contradiction:
Quantity of substanceVSVolume of moving object

Solution Approach 1:

The patent employs a nested arrangement where battery modules are positioned within the battery pack housing in a compact configuration. The modules are arranged to utilize space efficiently, with controllers and other components integrated into the same housing structure, minimizing the overall volume required for a given energy storage capacity.

Inventive Principle:
Principle #7Nested doll (Nesting)

3Volume of moving object

If battery modules are closely arranged to improve space utilization, then the space occupation is reduced, but the heat dissipation efficiency deteriorates

Engineering Contradiction:
Improvespace occupationVSAvoidheat dissipation efficiency
Core Design Contradiction:
Volume of moving objectVSTemperature

Solution Approach 1:

The patent introduces thermal management components as intermediaries between the battery modules. These components facilitate heat transfer from the closely arranged battery modules to the cooling system, enabling efficient heat dissipation despite the compact arrangement. The thermal management system acts as a mediator that resolves the conflict between close spacing and heat dissipation.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Device complexity

If a fixed battery pack structure is used to simplify the design, then the device complexity is reduced, but the adaptability to different installation environments deteriorates

Engineering Contradiction:
Improvedesign simplicityVSAvoidinstallation adaptability
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent incorporates adjustable and configurable elements within the battery pack design. The housing and mounting structures allow for adaptation to different installation environments while maintaining a relatively simple overall design. This dynamic capability enables the same basic design to be deployed in various configurations without requiring completely different designs for each application.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP4515584B1An energy storage system
Publication Date: 2026.04.15 HITACHI ENERGY LTD
  • EP4515584B1 patent drawingFigure 1
  • EP4515584B1 patent drawingFigure 2
  • EP4515584B1 patent drawingFigure 3

AI summary

An energy storage unit comprising a first unit terminal and a second unit terminal, an energy storage element having a first element terminal and a second element terminal, wherein the second element terminal is connected with the second unit terminal, and a protection circuit comprising a first pyrotechnic switch connected between the first unit terminal and the first element terminal and a second pyrotechnic switch connected between the first unit terminal and the second unit terminal.