Negative Electrode SEI Pre-Formation in Lithium-Treated Reactors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for manufacturing negative electrodes for all-solid-state batteries fail to form a stable solid electrolyte interface (SEI) film, leading to irreversible lithium consumption and reduced battery capacity and lifespan.
Innovation Solution
A method involving a reactor with a lithium-treated inner surface is used to mix a negative electrode active material, solid electrolyte, and conductive agent, forming an SEI film through controlled reactions with electrolytic solution, including Stage I and II reactions to create a stable SEI film on the negative electrode active material.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a negative electrode active material is used without pre-forming an SEI film, then the manufacturing process is simple, but irreversible lithium consumption occurs and battery lifespan is reduced
Solution Approach 1:
The invention applies preliminary action by forming an SEI film on the negative electrode active material before assembling the battery. This is achieved by contacting the negative electrode active material with lithium ions in advance, creating a stable interface layer that prevents subsequent irreversible lithium consumption during battery operation, thereby extending battery lifespan without significantly complicating the manufacturing process
2Reliability
If an SEI film is formed by conventional methods after battery assembly, then battery lifespan may be improved, but the manufacturing process becomes complicated and additional lithium doping steps are required
Solution Approach 1:
The invention reverses the conventional sequence by performing SEI film formation before battery assembly rather than after. This preliminary action eliminates the need for subsequent lithium doping steps and complex post-assembly processing, while still achieving the reliability benefits of a stable SEI film
Solution Approach 2:
The invention inverts the conventional manufacturing sequence where SEI film formation typically occurs after battery assembly. By forming the SEI film on the negative electrode active material before assembly, the process simplifies manufacturing while maintaining the reliability improvements associated with having a pre-formed stable SEI film
3Stability of the object's composition
If lithium ions are continuously consumed to replenish the SEI film during charging and discharging, then the SEI film remains intact, but battery capacity is remarkably reduced
Solution Approach 1:
By forming a complete and stable SEI film before battery operation through preliminary contact with lithium ions, the invention eliminates the need for continuous lithium consumption during charging and discharging cycles. The pre-formed SEI film acts as a stable interface that does not require replenishment, thereby preserving battery capacity while maintaining SEI film integrity
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 method ensures a stable SEI film is formed before assembly, preventing irreversible lithium consumption and enhancing battery capacity and lifespan by minimizing SEI film breakdown during charging and discharging.
Implementation Method 1
lithium ions that have reacted with an electrolytic solution form a solid electrolyte interface (SEI) film on the surface of a negative electrode active material
Implementation Method 2
forming a solid electrolyte interface (SEI) film while rotating the reactor, wherein the inner surface of the reactor is treated with lithium metal
Data Source
AI summary
Disclosed is a method of manufacturing a negative electrode for all-solid-state batteries, the method including (a) preparing a powder mixture including a negative electrode active material, a solid electrolyte, and a conductive agent, (b) introducing the powder mixture into a reactor, (c) introducing an electrolytic solution into the reactor, and (d) forming a solid electrolyte interface (SEI) film while rotating the reactor, wherein the inner surface of the reactor is treated with lithium metal.