Secondary Battery Current Collecting Plate Thickness Segmentation

Solution Overview

Problem

Current collecting plates in secondary batteries face challenges in achieving optimal weldability, electrical resistance, and strength, as they are either too thick, leading to decreased weldability, or too thin, increasing electrical resistance and compromising support for the electrode assembly.

Innovation Solution

A current collecting plate design featuring a thick current collecting part with a vent hole and a thinner welding part, where the welding part is inserted into the vent hole and welded to the electrode assembly, providing enhanced weldability and strength while minimizing electrical resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the current collecting plate is made thicker to reduce electrical resistance and improve strength, then electrical resistance decreases and support strength improves, but weldability deteriorates

Engineering Contradiction:

Improvestrength of current collecting plateVSAvoidweldability of current collecting plate

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The current collecting plate is divided into two distinct parts: a thick current collecting part (1.2-1.5mm) for electrical conduction and structural support, and a thin welding part (0.2-0.5mm) for optimal weldability. This segmentation allows each part to have the thickness optimized for its specific function, resolving the contradiction between strength and weldability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the current collecting plate have different thicknesses tailored to their functional requirements. The current collecting part has greater thickness for electrical performance and mechanical strength, while the welding part has reduced thickness for manufacturability. This local differentiation of properties resolves the contradiction by optimizing each region for its specific purpose.

Inventive Principle:

Principle #3Local quality

2Ease of manufacture

If the current collecting plate is made thinner to improve weldability, then weldability improves, but electrical resistance increases and support strength decreases

Engineering Contradiction:

Improveweldability of current collecting plateVSAvoidstrength of current collecting plate

Core Design Contradiction:

Ease of manufactureVSStrength

Solution Approach 1:

The current collecting plate is divided into two distinct parts: a thick current collecting part (1.2-1.5mm) for electrical conduction and structural support, and a thin welding part (0.2-0.5mm) for optimal weldability. This segmentation allows each part to have the thickness optimized for its specific function, resolving the contradiction between strength and weldability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the current collecting plate have different thicknesses tailored to their functional requirements. The current collecting part has greater thickness for electrical performance and mechanical strength, while the welding part has reduced thickness for manufacturability. This local differentiation of properties resolves the contradiction by optimizing each region for its specific purpose.

Inventive Principle:

Principle #3Local quality

3Loss of substance

If the current collecting plate is made thinner to reduce material usage, then material consumption decreases, but electrical resistance increases

Engineering Contradiction:

Improvematerial usage of current collecting plateVSAvoidelectrical resistance of current collecting plate

Core Design Contradiction:

Loss of substanceVSReliability

Solution Approach 1:

The current collecting plate is divided into two distinct parts: a thick current collecting part (1.2-1.5mm) for electrical conduction and structural support, and a thin welding part (0.2-0.5mm) for optimal weldability. This segmentation allows each part to have the thickness optimized for its specific function, resolving the contradiction between strength and weldability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the current collecting plate have different thicknesses tailored to their functional requirements. The current collecting part has greater thickness for electrical performance and mechanical strength, while the welding part has reduced thickness for manufacturability. This local differentiation of properties resolves the contradiction by optimizing each region for its specific purpose.

Inventive Principle:

Principle #3Local quality

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 achieves reduced electrical resistance, improved strength to support the electrode assembly, and enhanced weldability, ensuring stability and efficient current collection.

Implementation Method 1

a welding part configured to be welded to the electrode assembly and the current collecting part

Methodology Applied

Scientific EffectWelding: Welding

Data Source

PatentUS9012064B2Current collecting plate and secondary battery including current collecting plate

Publication Date: 2015.04.21 SAMSUNG SDI CO LTD

AI summary

A secondary battery includes an electrode assembly including a positive electrode, a negative electrode, and separators which are wound together, current collecting plates attached to the electrode assembly, a case configured to accommodate the electrode assembly and the current collecting plates, and a cap configured to cover an opening of the case and electrically connect to the current collecting plates. Each of the current collecting plates includes a current collecting part and a welding part. The current collecting parts electrically connect to the electrode assembly. The welding part is welded to the electrode assembly and the current collecting part.