Solid-State Battery Anode Layer With Amorphous Carbon for Dendrite Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The growth of lithium dendrites in all-solid-state secondary batteries using lithium as an anode active material can lead to short circuits and capacity reduction, limiting the battery's performance and lifespan.
Innovation Solution
The all-solid-state secondary battery incorporates an anode layer with a mixture of lithium as the anode active material and amorphous carbon, with a weight ratio of 1:3 to 1:1, and a sheet resistance of about 0.5 milliohms-centimeters or less, to inhibit lithium dendrite growth.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If lithium is used as the anode active material to increase energy density, then the specific capacity increases about 10 times compared to graphite, but lithium dendrites grow in a branching tree-like fashion causing short circuits and capacity reduction
Solution Approach 1:
The anode layer is constructed as a composite material combining lithium (anode active material) with amorphous carbon (conductive agent). This composite structure allows the lithium to provide high specific capacity while the amorphous carbon network prevents dendrite growth by providing alternative conduction pathways and mechanical stability, thus resolving the contradiction between high capacity and short circuit prevention
Solution Approach 2:
The patent optimizes the weight ratio parameter of lithium to amorphous carbon to be within 1:10 to 1:1, and controls the sheet resistance of the anode layer to be 0.5 milliohms-centimeters or less. These parameter changes ensure that there is enough amorphous carbon to suppress dendrite growth while maintaining sufficient lithium content for high capacity, and the low sheet resistance ensures good electrical conductivity
2Quantity of substance
If the anode layer uses pure lithium to maximize capacity, then the energy density increases, but the sheet resistance becomes too high and dendrite growth is promoted
Solution Approach 1:
The anode layer combines lithium particles with amorphous carbon particles to form a composite structure. The amorphous carbon provides a conductive matrix that reduces the overall sheet resistance of the anode layer while allowing high lithium content for maximum energy density. The composite nature ensures both electrical conductivity and dendrite suppression
Solution Approach 2:
The patent specifies that the anode layer must have a sheet resistance of 0.5 milliohms-centimeters or less. This parameter control is achieved by optimizing the amount and distribution of amorphous carbon in the composite anode layer, ensuring sufficient electrical conductivity while maintaining high lithium content for energy density
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 configuration enhances the binding force between the anode active material layer and the anode current collector, reduces sheet resistance, and improves the charge/discharge reaction speed, thereby increasing the discharge capacity and maintaining battery performance.
Implementation Method 1
an anode active material layer disposed on the anode current collector, the anode active material layer including an anode active material and amorphous carbon
Implementation Method 2
the anode layer has sheet resistance of about 0.5 milliohms-centimeters or less
Data Source
AI summary
An all-solid-state secondary battery includes: a cathode layer including a cathode active material, an anode layer including an anode current collector and an anode active material layer disposed on the anode current collector, the anode active material layer including an anode active material and amorphous carbon, and a solid electrolyte layer disposed between the cathode active material layer and the anode active material layer, wherein a weight ratio of the anode active material to the amorphous carbon is 1:3 to 1:1, and the anode layer has sheet resistance of about 0.5 milliohms-centimeters or less.