Fiberized Zinc Battery Negative Electrode for Longer Cycle Life
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Zinc secondary batteries face shortened cycle life due to morphological changes of the negative electrode active material, leading to increased resistance and difficulty in charge and discharge processes, which existing solutions have not adequately addressed.
Innovation Solution
A negative electrode comprising ZnO particles and Zn particles with a binder that is a mixture of binder particles and fibers, where the average fiber diameter of the binder fibers is between 0.05 to 0.17 μm and the fiberization ratio is 20 to 70%, inhibiting morphological changes and enhancing durability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If zinc is used as negative electrode active material, then high capacity is achieved, but morphological changes occur during charge/discharge cycles leading to shortened battery life
Solution Approach 1:
The patent applies preliminary action by pre-forming the negative electrode with a specific composite structure containing zinc particles, zinc oxide particles, and binder resin before battery operation. This pre-configured structure proactively prevents morphological changes during subsequent charge/discharge cycles, addressing the reliability issue before it manifests.
Solution Approach 2:
The patent employs composite materials by combining zinc particles, zinc oxide particles, and binder resin in a specific composition ratio. This composite structure leverages the advantages of each component: zinc for capacity, zinc oxide for structural stability, and binder resin for maintaining morphology, thereby resolving the contradiction between high capacity and long cycle life.
2Productivity
If zinc repeatedly dissolves and precipitates during charge/discharge, then electrochemical activity is maintained, but pore clogging occurs causing high resistance
Solution Approach 1:
The patent utilizes porous materials by incorporating zinc oxide particles with controlled porosity into the negative electrode composite. The porous structure of zinc oxide provides pathways that prevent pore clogging during zinc dissolution and precipitation, maintaining low resistance while preserving charge/discharge activity.
Solution Approach 2:
The binder resin acts as an intermediary material between zinc particles and the electrode substrate. It mediates the repeated dissolution and precipitation of zinc by providing a flexible matrix that accommodates volume changes and prevents direct contact between zinc deposits and pore structures, thereby preventing resistance increase.
3Quantity of substance
If isolated zinc accumulates on the negative electrode, then active material is lost, but charge/discharge becomes difficult
Solution Approach 1:
The patent applies merging by combining zinc particles with zinc oxide particles and binder resin into a unified composite structure. This merged structure prevents isolated zinc accumulation by ensuring zinc remains integrated within the composite matrix, maintaining both active material content and charge/discharge performance.
Solution Approach 2:
The patent utilizes parameter changes by controlling the particle size distribution, composition ratio, and morphological parameters of the composite materials. By optimizing these parameters, the electrode structure maintains zinc in a dispersed, integrated state rather than isolated accumulations, preserving both quantity and operational efficiency.
Data Source
AI summary
Provided is a negative electrode for use in a zinc secondary battery, including a negative electrode active material containing ZnO particles and Zn particles, and a binder that is a mixture of binder particles composed of a binder resin and binder fibers composed of the binder resin, in which, in an image analysis of the negative electrode, an average fiber diameter of the binder fibers is 0.05 to 0.17 μm, and a fiberization ratio, which is a ratio of an area of the binder fibers to the total area of the binder particles and the binder fibers, is 20 to 70%.