Dual-Layer Inter-Module Busbar Insulation Under Fire Exposure

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional inter-module busbars face issues with increased volume and weight due to additional fire-resistant components, and they fail to maintain insulation when the outer insulating layer is burned away, leading to potential short circuits during fires.

Innovation Solution

An inter-module busbar design featuring a metal plate with a first insulating layer that expands at high temperatures and a second insulating layer that ceramizes at high temperatures, where the first layer fills cracks in the second layer to prevent exposure of the metal plate, maintaining insulation even during fires.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a conventional single-layer insulating structure is used, then the busbar has simple structure and small volume, but the insulation is compromised when the insulating layer is burned away by fire

Engineering Contradiction:

Improveinsulation reliabilityVSAvoidinsulating structure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The insulating structure is divided into two functional layers: a first insulating layer that expands when exposed to fire to fill cracks, and a second insulating layer that ceramizes to maintain structural integrity. This segmentation allows each layer to perform its specific function, ensuring reliable insulation during fire conditions without requiring a single complex material.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent employs a composite insulating structure combining two different materials with complementary fire responses. The first layer uses expandable material while the second layer uses ceramizing material, creating a composite system that leverages the advantages of both materials to maintain insulation reliability under thermal stress.

Inventive Principle:

Principle #40Composite materials

2Reliability

If additional fire-resistant components are added to maintain insulation during fire, then the insulation reliability improves, but the volume and weight of the busbar increase

Engineering Contradiction:

Improveinsulation reliabilityVSAvoidbusbar weight

Core Design Contradiction:

ReliabilityVSWeight of moving object

Solution Approach 1:

The patent changes the physical parameters of the insulating layers during fire exposure. The first layer undergoes volume expansion while the second layer undergoes chemical transformation to ceramic. These parameter changes allow the system to maintain insulation reliability without adding excessive weight, as the protective effect is achieved through transformation rather than sheer mass.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If a thicker insulating layer is used to prevent exposure during fire, then the insulation reliability improves, but the volume of the busbar increases

Engineering Contradiction:

Improveinsulation reliabilityVSAvoidbusbar volume

Core Design Contradiction:

ReliabilityVSVolume of moving object

Solution Approach 1:

The insulating system is designed to be dynamic rather than static. The first insulating layer actively expands when exposed to fire, increasing its protective volume only when needed. This dynamic response maintains insulation reliability during fire conditions without requiring a permanently larger busbar volume during normal operation.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent utilizes phase transitions of the insulating materials in response to thermal stress. The first layer transitions from a compact state to an expanded state, while the second layer transitions to a ceramized state. These phase transitions provide enhanced protection during fire without increasing the normal-volume busbar dimensions.

Inventive Principle:

Principle #36Phase transitions

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 design effectively prevents short circuits by ensuring the metal plate remains insulated, even when the outer insulating layer is damaged, while minimizing the increase in volume and weight of the busbar.

Implementation Method 1

a first insulating layer configured to enclose at least a part of the metal plate, the first insulating layer being expandable at high temperatures

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 2

a second insulating layer added to the first insulating layer, the second insulating layer being configured to be ceramized at high temperatures

Methodology Applied

Scientific EffectCeramization: Vitrification

Data Source

PatentUS20240405381A1Inter-Module Busbar Including Insulating Layer and Battery Pack Including the Same

Publication Date: 2024.12.05 LG ENERGY SOLUTION LTD

AI summary

The present invention relates to an inter-module busbar including a metal plate for electrical connection, a first insulating layer configured to enclose at least a part of the metal plate and being expandable at high temperatures, and a second insulating layer added to the first insulating layer and being configured to be ceramized at high temperatures. The metal plate in the busbar is not exposed in the event of fire, whereby short circuit due to contact with the metal plate may be prevented.