Elastic Battery Module Structure for Cell Swelling Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing battery modules face challenges in preventing battery cell swelling due to deformation during charging and discharging, which complicates the manufacturing process and requires additional pressing steps, and existing solutions are inadequate in absorbing the expansion and contraction of battery cells.

Innovation Solution

A battery module design featuring an exterior member made of elastic material, such as a thermal contraction tube, surrounding the battery cell stack with elastic members like flat springs to absorb expansion and contraction, and a simplified structure that eliminates the need for separate pressing processes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If compressive pads are attached to lateral sides of battery cell stack and pressing process is applied, then battery cell swelling is prevented, but manufacturing process complexity increases

Engineering Contradiction:

Improvebattery cell swelling preventionVSAvoidmanufacturing process complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent removes the compressive pads from the lateral sides of the battery cell stack, extracting the harmful element that caused both swelling and manufacturing complexity. Instead of using pads that require pressing processes, the invention uses the exterior member's inherent elastic properties to achieve the same protective function without the additional components and process steps.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The exterior member is designed with elastic material properties that enable it to automatically absorb expansion and contraction forces from battery cells during charging and discharging. This self-service mechanism eliminates the need for external compressive pads and pressing processes, as the exterior member inherently provides the necessary constraint and protection.

Inventive Principle:

Principle #25Self-service

2Reliability

If compressive pads are used to constrain battery cells, then swelling is reduced, but the pads become permanently deformed due to excessive reaction force

Engineering Contradiction:

Improvebattery cell swelling preventionVSAvoidcompressive pad durability

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The patent changes the material parameter of the exterior member to elastic material, which fundamentally alters how the constraint force is applied and absorbed. Unlike rigid compressive pads that become permanently deformed, the elastic exterior member can repeatedly deform and recover, maintaining its structural integrity and constraint capability throughout the battery's operational life.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The exterior member is designed to dynamically respond to battery cell expansion and contraction during charging and discharging cycles. The elastic material allows the exterior member to flexibly adapt to changing battery dimensions, providing continuous protection without suffering from permanent deformation that plagues static compressive pads.

Inventive Principle:

Principle #15Dynamics

3Use of energy by moving object

If battery cells are repeatedly charged and discharged, then energy storage function is achieved, but battery cell deformation and module swelling occur

Engineering Contradiction:

Improveenergy storage functionVSAvoidmodule dimensional stability

Core Design Contradiction:

Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

The patent implements beforehand cushioning by designing the exterior member with elastic properties that anticipate and prepare for the expansion and contraction forces generated during charging and discharging cycles. The elastic material acts as a pre-configured cushion that absorbs these repeated deformations, preventing them from propagating to the module frame and causing swelling, while still allowing the battery cells to perform their energy storage function.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

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 design effectively prevents battery cell swelling, enhances dimensional stability, simplifies the manufacturing process, improves cooling performance, and reduces component count, thereby increasing price competitiveness and efficiency.

Implementation Method 1

an elastic member (190) disposed between the exterior member (150) and the lateral side of the battery cell stack (120)

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

The exterior member may be configured as a thermal contraction tube, and the thermal contraction tube may be opened at upper and lower sides thereof

Methodology Applied

Scientific EffectThermal contraction: Thermal Contraction

Data Source

PatentEP4199216B1Battery module and battery pack including same

Publication Date: 2025.11.05 LG ENERGY SOLUTION LTD

Figure 1
Figure 2
Figure 3

AI summary

An exemplary embodiment of the present invention provides a battery module including: a battery cell stack including a plurality of battery cells stacked in a first direction; an exterior member configured to surround front and rear sides and two opposite lateral sides of the battery cell stack; a sensing block positioned at front and rear sides of the battery cell stack; and an elastic member disposed between the exterior member and the lateral side of the battery cell stack.