Composite Electrode Terminal Structure for Conductive Stress Relief

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The characteristics of conventional battery electrode terminals need enhancement.

Innovation Solution

The electrode terminal is composed of a first member made of copper or copper alloy, a second member made of copper alloy, and a third member made of aluminum or aluminum alloy, with the first and third members being adjacent but not in contact, and bonded with a conductive member using laser bonding, ensuring electrical conductivity and durability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the electrode terminal uses a single material (e.g., copper or aluminum), then the manufacturing process is simple, but the electrical conductivity and durability characteristics are insufficient

Engineering Contradiction:
Improveelectrical conductivity and durabilityVSAvoidmaterial composition
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The electrode terminal employs a composite structure consisting of a first terminal body (copper or copper alloy) and a second terminal body (aluminum or aluminum alloy). This composite material approach allows the terminal to combine the high electrical conductivity of copper with the lightweight and corrosion-resistant properties of aluminum, thereby improving overall reliability while managing manufacturing complexity through a structured multi-material design.

Inventive Principle:
Principle #40Composite materials

2Reliability

If the first member and third member are in direct contact, then the electrical conductivity is maximized, but stress concentration and deformation occur

Engineering Contradiction:
Improveelectrical conductivityVSAvoidstress resistance
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The second terminal body (aluminum or aluminum alloy) serves as an intermediary component between the first terminal body (copper) and the external conductive member. This intermediate aluminum layer maintains electrical conductivity pathways while mechanically decoupling the copper and aluminum components, thereby preventing stress concentration and deformation that would occur with direct contact between dissimilar metals.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Strength

If the electrode terminal uses traditional bonding methods, then the manufacturing process is simple, but the bonding strength and durability are insufficient

Engineering Contradiction:
Improvebonding strengthVSAvoidbonding process
Core Design Contradiction:
StrengthVSEase of manufacture

Solution Approach 1:

The patent replaces traditional mechanical bonding methods (such as riveting or screw fastening) with laser welding technology. This substitution enables direct metallurgical bonding between the copper-based first terminal body and the aluminum-based second terminal body, achieving superior bonding strength and durability while maintaining manufacturing efficiency through automated laser processing.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

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 configuration enhances the characteristics of the battery electrode terminal, improving electrical conductivity and durability while maintaining a gap for stress reduction and assemblability.

Implementation Method 1

bonded with the first member and including the first metal

Methodology Applied
Scientific EffectLaser bonding: Laser Beam Welding

Implementation Method 2

The third member is bonded with a conductive member including the second metal, on a facing surface facing the conductive member that electrically connects a first battery and a second battery

Methodology Applied
Scientific EffectLaser bonding: Laser Beam Welding

Data Source

PatentEP4629430A1Electrode terminal and battery
Publication Date: 2025.10.08 VEHICLE ENERGY JAPAN INC
  • EP4629430A1 patent drawingFigure 1
  • EP4629430A1 patent drawingFigure 2~3
  • EP4629430A1 patent drawingFigure 4~5

AI summary

An electrode terminal (negative electrode terminal 420) includes: a first member 421 that is electrically connected with a charge/discharge body 100 of a battery 1, and includes a first metal (copper or a copper alloy); a second member 422 that includes a first insertion section 422x into which the first member 421 is inserted, the second member 422 being bonded with the first member 421 and including the first metal (copper or a copper alloy); and a third member 423 that includes a second insertion section 423x into which the first member 421 is inserted, the third member 423 being bonded with the second member 422 and including a second metal (aluminum or an aluminum alloy) which is a material different from the first metal (copper or a copper alloy). The third member 423 is bonded with a conductive member (busbar 10) including the second metal (aluminum or an aluminum alloy), on a facing surface P facing the conductive member (busbar 10) that electrically connects a first battery 1 and a second battery 1. The first member 421 and the third member 423 are adjacent to each other on a side of the facing surface P.