Dry-Processed Graphite Negative Electrode for Fast-Charging Batteries
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for manufacturing negative electrodes in lithium secondary batteries involve complex processes with high energy consumption and difficulty in quality control, particularly due to the need for magnetic fields and solvents to orient graphite, which affects the high-rate charging characteristics.
Innovation Solution
A dry process is used to orient graphite in a predetermined direction by preparing a powder mixture with a binder, forming graphite granules and films, and laminating them onto a negative electrode substrate, eliminating the need for magnetic particles and solvents, thereby simplifying the process and improving charging characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If magnetic particles and solvents are used to orient graphite in conventional wet processes, then graphite orientation is achieved, but process complexity increases and energy consumption rises
Solution Approach 1:
The invention extracts and removes magnetic particles and solvents from the graphite orientation process, replacing the complex wet process with a simplified dry process that achieves orientation through mechanical rolling alone
Solution Approach 2:
The invention replaces the magnetic field-based orientation mechanism with a mechanical rolling system, where rollers apply physical force to orient graphite particles during the coating process, eliminating the need for magnetic particles
2Manufacturing precision
If magnetic fields are applied to orient graphite in conventional methods, then graphite orientation is achieved, but energy consumption increases
Solution Approach 1:
The invention replaces energy-intensive magnetic field application with low-energy mechanical rolling, where the rollers' physical motion provides the orienting force without requiring sustained high energy input
3Ease of manufacture
If conventional wet processes are used with solvents, then graphite can be applied to the substrate, but manufacturing cost increases and quality control becomes difficult
Solution Approach 1:
The invention extracts solvents from the process entirely, using a dry coating method where graphite powder is directly applied and oriented on the substrate through mechanical rolling, eliminating solvent-related quality control issues
Solution Approach 2:
The invention uses a simple disposable coating structure where graphite powder is directly deposited without requiring solvent systems, reducing both material costs and quality control complexity
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
This method enhances high-rate charging and discharging capabilities while reducing manufacturing costs and energy density, achieving improved performance and efficiency compared to conventional wet processes.
Implementation Method 1
a binder, which binds the plate-shaped graphite to each other
Implementation Method 2
applying heat and pressure to the graphite granules, thereby orienting the plate-shaped graphite in a predetermined direction
Implementation Method 3
applying heat and pressure to the negative electrode substrate, thereby laminating the graphite film on the negative electrode substrate
Data Source
AI summary
Provided are a negative electrode manufacturing method capable of forming a graphite layer oriented in one direction by using a dry process, and a negative electrode and a lithium secondary battery manufactured using the method. The manufacturing method includes: preparing a powder mixture including a plate-shaped graphite and a binder; a granulation step of preparing a graphite granule by processing the powder mixture such that graphite is oriented in one direction; preparing a graphite film in which the graphite is oriented in a thickness direction by shaping the prepared graphite granule; and laminating the graphite film on at least one surface of a negative electrode substrate.