Halogen Salt Additives for Metal Anode Dendrite Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Rechargeable lithium and sodium metal-based batteries face instability due to non-uniform metal deposition and dendrite formation on the negative electrode anode during charge and discharge cycles, hindering commercialization.
Innovation Solution
A well-defined solid electrolyte interface (SEI) layer is formed using simple halogen containing salts in the liquid electrolyte, which facilitates uniform metal deposition by controlling metal ion migration and flux distribution, thereby mitigating dendrite growth.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If conventional liquid electrolytes are used in metal-based batteries, then the battery can operate with simple structure, but non-uniform metal deposition and dendrite formation occur on the negative electrode anode
Solution Approach 1:
The patent introduces a solid electrolyte interface (SEI) layer as an intermediary between the liquid electrolyte and the metal anode. This SEI layer, formed by specific electrolyte additives, mediates the interaction between electrolyte and metal surface, controlling metal ion flux distribution and preventing direct contact between liquid electrolyte and metal anode that causes dendrite formation
Solution Approach 2:
The patent modifies the electrolyte composition by adding specific concentrations of halogen-containing salts (such as LiCl, LiBr, LiI at 0.1-10 mM concentrations) to change the physical and chemical parameters of the electrolyte system. These parameter changes lead to formation of a stable SEI layer with controlled ion transport properties, transforming the electrolyte's interaction with the metal surface
2Reliability
If halogen containing salts are added to form a salt-rich SEI layer, then uniform electrodeposition is achieved, but the electrolyte composition becomes more complex
Solution Approach 1:
The patent applies local quality by creating a SEI layer with specific composition and structure only at the metal anode surface where it is needed. The bulk electrolyte remains relatively simple while the local region at the electrode interface has modified properties (salt-rich composition) that enable uniform deposition. This localized modification avoids the need to complicate the entire electrolyte system
3Reliability
If a stable SEI layer is formed to control metal ion migration, then dendrite formation is reduced, but the manufacturing process requires additional considerations
Solution Approach 1:
The patent employs preliminary action by including halogen-containing salt additives in the electrolyte composition before battery assembly. These additives automatically form the stable SEI layer during the initial charging cycles or formation process, before the battery enters normal operation. This preliminary formation step ensures dendrite suppression is already in place, eliminating the need for complex post-assembly treatments or specialized manufacturing equipment
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 solution provides stable and long-term cycling performance with reduced dendrite formation, enhancing the safety and efficiency of metal-based batteries, allowing for hundreds of cycles and thousands of hours of operation without instability.
Implementation Method 1
unstable electrodeposition of lithium, sodium and other metals within metal-based batteries is strongly related to the properties of a so-called solid electrolyte interface (SEI) layer formed on, for example, a lithium metal surface or a sodium metal surface at an initial stage of metal-based battery operation by chemical and electrochemical reactions with electrolyte components
Implementation Method 2
a well-defined SEI layer is thought to be advantageous for its ability to guide stable and even deposition by controlling the rate of metal ion migration and the distributing of the metal ion flux near a metal electrode anode surface
Implementation Method 3
the simple halogen containing material additives in accordance with the embodiments are constantly present in the electrolyte allowing repair of the SEI for long-term effectiveness of a resulting metal-based battery
Data Source
AI summary
A metal-based battery includes at least one metal electrode immersed within an electrolyte that includes: (1) an aprotic solvent; (2) a simple halogen containing material; and (3) optionally a metal salt that includes a complex halogen containing anion. The simple halogen containing material may include a metal halide salt that includes a metal cation selected from the group including but not limited to lithium and sodium metal cations. The metal halide salt may also include a halide anion selected from the group consisting of fluoride, chloride, bromide and iodide halide anions. The use of the metal halide salt within the metal-based battery provides enhanced cycling ability within the metal-based battery. Also contemplated are additional simple halogen containing material additives that may enhance cycling performance of a metal-based battery.