Curved Secondary Battery Reinforcing Layer Shape Stability

Solution Overview

Problem

Secondary batteries with curved designs face challenges in maintaining their shape due to volume expansion forces during charging and discharging, which can lead to shape deformation and damage within electronic devices.

Innovation Solution

A secondary battery design that includes a reinforcing layer with a curvature matching the battery's surface, made from materials like polypropylene, polyethylene terephthalate, or polyimide, which provides greater bending strength than the volume expansion force, coupled with a bonding layer to maintain the battery's shape and prevent deformation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a curved secondary battery is designed to fit electronic devices with curved surfaces, then the battery can maintain ergonomic design and adapt to device shapes, but the battery experiences shape deformation and damage due to volume expansion forces during charging and discharging

Engineering Contradiction:

Improveadaptability to curved electronic device shapesVSAvoidshape stability during charging and discharging

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The battery structure is segmented into multiple functional layers: a flexible pouch body for curvature adaptation, a reinforcing layer for shape stability, and a bonding layer for coupling. This segmentation allows each layer to perform its specific function - the pouch provides flexibility for curved surfaces while the reinforcing layer counteracts volume expansion forces during charging cycles

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The battery employs a composite structure combining the flexible pouch material with a rigid reinforcing layer made of materials such as polypropylene, polyethylene terephthalate, polyimide, or polyphenylene sulfide. This composite design enables the battery to simultaneously achieve flexibility for curved surface adaptation and structural rigidity to resist deformation from electrochemical volume expansion

Inventive Principle:

Principle #40Composite materials

2Ease of operation

If the battery structure is made flexible to conform to curved surfaces, then the battery can be installed in various electronic devices, but the battery cannot resist volume expansion forces and maintains its shape

Engineering Contradiction:

Improveease of installation in curved devicesVSAvoidresistance to volume expansion force

Core Design Contradiction:

Ease of operationVSStrength

Solution Approach 1:

The battery uses a flexible pouch shell that can conform to curved surfaces of electronic devices, providing ease of installation and adaptation. The pouch structure allows the battery to be bent and shaped to fit various device geometries while maintaining sealing and protection of internal components

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The battery structure is segmented into multiple functional layers: a flexible pouch body for curvature adaptation, a reinforcing layer for shape stability, and a bonding layer for coupling. This segmentation allows each layer to perform its specific function - the pouch provides flexibility for curved surfaces while the reinforcing layer counteracts volume expansion forces during charging cycles

Inventive Principle:

Principle #1Segmentation

Solution Approach 3:

The battery employs a composite structure combining the flexible pouch material with a rigid reinforcing layer made of materials such as polypropylene, polyethylene terephthalate, polyimide, or polyphenylene sulfide. This composite design enables the battery to simultaneously achieve flexibility for curved surface adaptation and structural rigidity to resist deformation from electrochemical volume expansion

Inventive Principle:

Principle #40Composite materials

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 reinforcing layer effectively maintains the battery's shape by reducing volume expansion, ensuring the battery retains its curvature even after repeated charging and discharging cycles, preventing damage and efficient use within electronic devices.

Implementation Method 1

a bonding layer coupling the reinforcing layer to the first sealing sheet

Methodology Applied

Scientific EffectAdhesion: Adhesive

Implementation Method 2

a volume expansion force generated when the electrode assembly is charged

Methodology Applied

Scientific EffectVolume expansion: Thermal Expansion

Data Source

PatentUS9768419B2Curved secondary battery and method of manufacturing the same

Publication Date: 2017.09.19 SAMSUNG SDI CO LTD

AI summary

A curved secondary battery includes an electrode assembly; a first sealing sheet at a first surface of the electrode assembly; a second sealing sheet at a second surface of the electrode assembly, the first sealing sheet and the second sealing sheet together sealing the electrode assembly; and a reinforcing layer on the first sealing sheet, wherein the first sealing sheet has a concavely curved surface, and wherein the reinforcing layer has a curvature corresponding to a curvature of the first sealing sheet.