Cylindrical Battery Current Collector for Impact-Resistant Low Resistance

Solution Overview

Problem

Conventional cylindrical batteries face issues with damage from external impacts and vibrations, excessive heat generation during rapid charging, and low energy density due to poor current collection efficiency and internal resistance, which can lead to safety concerns and inefficiencies in electrical wiring for vehicle applications.

Innovation Solution

The cylindrical battery design features an electrode assembly with uncoated portions at the top and bottom, a current collecting plate with a rim portion and terminal coupling portion, and an insulating gasket to disperse impact, reduce internal resistance, and enhance energy density, while using silicon-based negative electrodes and optimized positive electrode active materials to improve thermal stability and charge/discharge efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If electrode tabs are provided on both sides of the jelly-roll with current collecting plates coupled to maximize contact area, then current collection efficiency is improved and resistance is minimized, but the coupling portion becomes vulnerable to damage from external impacts and vibrations

Engineering Contradiction:

Improvecurrent collection efficiencyVSAvoidcoupling portion durability

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The current collecting plate is divided into a body portion and a separate terminal coupling portion connected by a connection portion. This segmentation allows the coupling portion to be designed with appropriate flexibility and strength characteristics, reducing stress concentration at the welding interface while maintaining effective current collection.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The connection portion between the body and terminal coupling portion is designed with specific structural characteristics (such as reduced thickness or increased flexibility) to locally absorb and distribute mechanical stress. This local quality change protects the welding portion from impact and vibration damage while maintaining overall current collection efficiency.

Inventive Principle:

Principle #3Local quality

2Strength

If the coupling surface area between components is reduced due to partial damage to the welding area, then structural integrity is maintained, but excessive heat generation occurs due to increased resistance

Engineering Contradiction:

Improvewelding area integrityVSAvoidheat generation

Core Design Contradiction:

StrengthVSLoss of energy

Solution Approach 1:

The terminal coupling portion is designed with sufficient initial contact area and conductivity to provide a backup current path. If the primary welding area is partially damaged, the preliminary designed redundancy in the coupling structure prevents excessive resistance increase and heat generation.

Inventive Principle:

Principle #10Preliminary action

3Quantity of substance

If a cylindrical battery is designed for large capacity and high output, then energy density is improved, but the battery becomes more susceptible to damage from external impacts and vibrations during vehicle use

Engineering Contradiction:

Improvebattery capacityVSAvoidresistance to external impact

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The current collecting plate is divided into a body portion and a separate terminal coupling portion connected by a connection portion. This segmentation allows the coupling portion to be designed with appropriate flexibility and strength characteristics, reducing stress concentration at the welding interface while maintaining effective current collection.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The connection portion between the body and terminal coupling portion is designed with specific structural characteristics (such as reduced thickness or increased flexibility) to locally absorb and distribute mechanical stress. This local quality change protects the welding portion from impact and vibration damage while maintaining overall current collection efficiency.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS20250015402A1Cylindrical battery, and battery pack and vehicle including the same

Publication Date: 2025.01.09 LG ENERGY SOLUTION LTD

AI summary

Disclosed is a cylindrical battery, which includes an electrode assembly; a battery housing accommodating the electrode assembly and electrically connected to the second uncoated portion; a cap plate configured to seal the open portion of the battery housing; a current collecting plate having a rim portion, an uncoated portion coupling portion coupled to the first uncoated portion, and a terminal coupling portion spaced apart from the uncoated portion coupling portion; an electrode terminal riveted through a perforated hole formed in a closed portion and coupled to the terminal coupling portion; and an insulating gasket interposed between the electrode terminal and the perforated hole, wherein the electrode terminal includes a body portion; an outer flange portion; an inner flange portion; and a flat portion provided on an inner side of the inner flange portion and coupled to the terminal coupling portion.