Graphene Cathode Pouch Cell Without Sintering Activation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional lithium-ion batteries face issues such as capacity fade and safety risks due to liquid electrolytes, while solid-state batteries suffer from costly and time-consuming fabrication processes, especially in pouch cells, which also require high manufacturing costs and complex processes.
Innovation Solution
A solid-state battery design comprising a cathode with Li ions, graphene, and optionally a binder, an electrolyte, and an anode, particularly in the form of a pouch cell, which omits the need for spark plasma sintering and pressure activation, utilizing activated graphene to enhance cycle stability and conductivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional fabrication methods (spark plasma sintering, pressure activation) are used to improve solid electrolyte/electrode contacts, then interfacial resistance is reduced and cycle lifetime is extended, but manufacturing cost and fabrication time increase significantly
Solution Approach 1:
The cathode is pre-coated with a conductive layer (graphene, carbon black, or metal oxide) during the standard slurry coating process, before electrode assembly. This preliminary conductive coating ensures good interfacial contact with the solid electrolyte is achieved from the outset, eliminating the need for subsequent costly and time-consuming sintering or pressure activation steps.
Solution Approach 2:
The invention changes the chemical and physical parameters of the electrode surface by incorporating conductive materials (graphene, carbon black, metal oxides) into the cathode slurry. This modifies the interfacial properties between the cathode and solid electrolyte, improving conductivity and contact without requiring extreme temperature or pressure conditions.
2Weight of moving object
If pouch cell design is adopted to reduce weight and improve packing efficiency, then battery weight decreases and energy density increases, but fabrication complexity and manufacturing cost increase
Solution Approach 1:
The conductive coating is applied to the cathode during the standard slurry coating process, before electrode assembly into the pouch cell. This preliminary action ensures that the conductive layer is already in place when the pouch cell is assembled, simplifying the overall fabrication process despite the complex pouch cell structure.
Solution Approach 2:
The conductive coating serves multiple functions: it improves electrical conductivity at the solid electrolyte interface, enhances cycle stability, and can be applied using standard slurry coating equipment. This multi-functionality reduces the need for additional specialized process steps in pouch cell manufacturing.
3Ease of manufacture
If liquid electrolytes are used in lithium-ion batteries, then ionic conductivity is high and manufacturing is simple, but safety risks increase due to thermal runaway and electrolyte leakage
Solution Approach 1:
The invention changes the physical state of the electrolyte from liquid to solid, fundamentally altering the safety profile. Solid electrolytes eliminate thermal runaway and leakage risks while maintaining ionic conductivity through the use of conductive interfacial layers that facilitate ion transport at the solid-solid interface.
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 battery achieves high capacity retention, maintaining at least 60% of its original capacity after 150 cycles, significantly outperforming conventional solid-state batteries, and allows for lighter, more efficient pouch cells with improved mechanical stability and electrical conductivity.
Implementation Method 1
utilizing activated graphene to enhance cycle stability and conductivity
Implementation Method 2
laminating said cathode, electrolyte and anode to form said solid-state battery
Data Source
AI summary
A solid-state battery, preferably a pouch cell, includes a cathode including cathode active material comprising Li ions, graphene, and optionally a binder; an electrolyte; and an anode, preferably a lithium anode, wherein said electrolyte is positioned in between said cathode and said anode.