Battery Box Beam Structure to Prevent Weld Separation Under Expansion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The welding surfaces in existing battery box beams are prone to cracking and separation due to being parallel to the extrusion force during battery expansion, compromising the anti-expansion and extrusion performance.

Innovation Solution

A battery box beam design with overlapping pressure bearing sections that are perpendicular to the extrusion force, featuring integral bending and sliding connections to enhance strength and resistance to extrusion, and a buffer section to absorb excessive forces.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the welding surface is positioned parallel to the extrusion force direction, then the welding process is simplified, but the welding surface is prone to cracking and separation under extrusion force

Engineering Contradiction:
Improvewelding process simplicityVSAvoidwelding surface integrity
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The patent changes the orientation of the welding surface from parallel to perpendicular relative to the extrusion force direction. The first and second pressure bearing sections are arranged perpendicular to the extrusion force, with their welding surfaces positioned at right angles to the force direction, thereby eliminating the cracking and separation problems that occur when welding surfaces are parallel to the extrusion force.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Strength

If the pressure bearing sections are arranged perpendicular to the extrusion force, then the resistance to extrusion force is enhanced, but the structural complexity increases

Engineering Contradiction:
Improveextrusion resistanceVSAvoidbeam structure complexity
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The patent combines the first pressure bearing section and the second pressure bearing section into a single integrated beam structure. The second pressure bearing section overlaps with the first pressure bearing section, and they are fixedly connected together, forming a unified anti-expansion beam that resists extrusion force while maintaining structural simplicity.

Inventive Principle:
Principle #5Merging (Combining)

3Reliability

If the first pressure bearing section and second pressure bearing section are fixedly connected, then the welding surface separation is prevented, but the ability to absorb excessive extrusion force is reduced

Engineering Contradiction:
Improvewelding surface stabilityVSAvoidforce absorption capability
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent introduces a buffer section that can dynamically respond to extrusion forces. The buffer section includes a sliding connection that allows relative movement between beam components when excessive extrusion force is applied. This sliding mechanism enables the structure to absorb excess force through controlled deformation while maintaining the fixed connection that prevents welding surface separation under normal operating conditions.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP4611138A1Battery box beam, battery box and battery module
Publication Date: 2025.09.03 EVE ENERGY CO LTD
  • EP4611138A1 patent drawingFigure 1
  • EP4611138A1 patent drawingFigure 2~3
  • EP4611138A1 patent drawingFigure 4

AI summary

The present disclosure provides a battery box beam, a battery box (1), and a battery module. The battery box beam includes a body wall (7); a first beam wall (8) connected to one end of the body wall (7), and the first beam wall (8) compries a first pressure bearing section (81) disposed opposite to the body wall (7); and a second beam wall (9) connected to another end of the body wall (7), the second beam wall (9) includes a second pressure bearing section (91), and the second pressure bearing section (91) is disposed opposite to the body wall (7) and extends towards and partially overlaps with the first pressure bearing section (81), thereby meeting the requirements of light-weight and strength of the battery module.