Stable Cycling of All-Solid-State Lithium Batteries Enabled by Cyano-Molecular Diamond Improved Polymer Electrolytes
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2024-06-17 |
| Journal | Nano-Micro Letters |
| Authors | Yang Dai, Mengbing Zhuang, Yi-Xiao Deng, Yuan Liao, Jian Gu |
| Institutions | Beijing Institute of Technology, Xiamen University |
| Citations | 16 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Cyano-Molecular Diamond Improved Polymer Electrolytes
Section titled âTechnical Documentation & Analysis: Cyano-Molecular Diamond Improved Polymer ElectrolytesâExecutive Summary
Section titled âExecutive SummaryâThis research validates the critical role of diamond-like structures in stabilizing high-voltage all-solid-state lithium metal batteries (ASSBs), providing a direct pathway for 6CCVDâs advanced diamond materials in next-generation energy storage.
- Core Achievement: Introduction of 1-Adamantanecarbonitrile (ADCN), a molecule containing a stable C10H15 âdiamond building block,â significantly enhances the performance of poly(ethylene oxide) (PEO) solid polymer electrolytes (SPEs).
- Interfacial Engineering: The ADCN additive promotes the formation of a dense, robust, LiF-rich Solid Electrolyte Interphase (SEI) and Cathode Electrolyte Interphase (CEI), effectively suppressing lithium dendrite growth and mitigating high-voltage degradation.
- Performance Metrics: The optimal ADCN-enhanced SPE (ADCN-2) achieved a 7x increase in Li$^{+}$ ionic conductivity (1.44 x 10-4 S cm-1 at 45 °C) and a high Li$^{+}$ transference number (tLi$^{+}$ = 0.38).
- Long-Term Stability: Li/Li symmetric cells demonstrated stable plating/stripping for over 2000 hours at 0.2 mA cm-2, and the critical current density (CCD) reached 1.1 mA cm-2.
- High-Voltage Cycling: The 4.3 V NMC811/Li ASSB achieved stable cycling for 1000 times with an impressive 80% capacity retention at 45 °C, demonstrating compatibility with high-energy density cathodes.
- 6CCVD Relevance: The work is explicitly inspired by nanodiamond research, confirming that diamond-based materials are essential for robust interfacial engineering in ASSBs, a key application area for 6CCVDâs MPCVD diamond products.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the research paper, highlighting the performance gains achieved using the ADCN-enhanced SPE (ADCN-2).
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Stable Cycling Temperature | 45 | °C | NMC811/Li ASSB performance |
| Maximum Operating Voltage | 4.3 | V | NMC811/Li ASSB |
| Li$^{+}$ Ionic Conductivity (Enhanced) | 1.44 x 10-4 | S cm-1 | ADCN-2 SPE at 45 °C (7x higher than baseline) |
| Li$^{+}$ Transference Number (tLi$^{+}$) | 0.38 | N/A | ADCN-2 SPE (vs. 0.25 baseline) |
| Critical Current Density (CCD) | 1.1 | mA cm-2 | Li/SPE/Li symmetric cell (ADCN-2) |
| Symmetric Cell Cycling Stability | >2000 | h | Li/SPE/Li at 0.2 mA cm-2 |
| NMC811 Capacity Retention (1000 cycles) | 80 | % | 4.3 V ASSB at 0.3 C, 45 °C |
| LFP Capacity Retention (1000 cycles) | 85 | % | ASSB at 0.3 C, 45 °C |
| Tensile Strength (Enhanced) | 5.1 | MPa | ADCN-2 SPE (vs. 1.3 MPa baseline) |
| LiTFSI Dissociation Energy Reduction (Li$^{+}$) | 0.10 | eV | Promoted by ADCN (3.99 eV to 3.89 eV) |
Key Methodologies
Section titled âKey MethodologiesâThe solid polymer electrolytes (SPEs) were prepared using a standard solvent-casting technique, incorporating the ADCN additive to leverage its âdiamond building blockâ structure.
- SPE Preparation Method: Classic solvent-casting approach was used to create the electrolyte membranes.
- Core Components: Poly(ethylene oxide) (PEO, Mw â 600,000) and Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) were dissolved in anhydrous acetonitrile (AN).
- Additive Incorporation: 1-Adamantanecarbonitrile (ADCN) was added at varying mass percentages (1 wt%, 5 wt%, 10 wt%) relative to PEO. The 5 wt% loading (ADCN-2) proved optimal.
- Processing Environment: All procedures were conducted in an Ar-filled glovebox (O2/H2O < 0.1 ppm).
- Membrane Formation: Solutions were poured onto a polytetrafluoroethylene (PTFE) plate and subsequently dried under vacuum at 80 °C for 36 hours.
- Electrode Fabrication: Cathodes (LiFePO4 or Ni0.8Mn0.1Co0.1O2 [NMC811]) were prepared by blending active material, conductive carbon, SPE composition, and PVDF binder in N-methyl-2-pyrrolidone (NMP).
- Cell Assembly: All-solid-state batteries (ASSBs) were assembled in 2032 coin cells using the cathode, SPE membrane, and Li metal anode.
- Characterization: Interfacial stability was confirmed using TOF-SIMS (detecting LiF2- and C10H15- species) and DFT calculations to model dissociation energies.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe research highlights that diamond-like structures are crucial for creating robust, high-voltage stable interfaces in ASSBs. 6CCVD is uniquely positioned to supply the foundational diamond materials necessary to replicate, scale, and advance this research using actual MPCVD diamond.
Applicable Materials
Section titled âApplicable MaterialsâThis research, inspired by nanodiamond additives, can be directly extended using 6CCVDâs high-purity diamond products for superior performance and stability in ASSB development:
| 6CCVD Material | Application in ASSB Research | Key Benefit |
|---|---|---|
| Polycrystalline Diamond (PCD) | Robust, large-area substrates or protective interlayers for anodes/cathodes. | High mechanical strength (up to 5.1 MPa achieved in the paper), chemical inertness, and thermal stability for high-temperature operation. |
| Single Crystal Diamond (SCD) | High-purity, ultra-smooth (Ra < 1 nm) protective coatings or windows for in situ characterization (e.g., Raman, FTIR). | Unmatched purity and structural perfection for fundamental studies of SEI/CEI formation mechanisms. |
| Boron-Doped Diamond (BDD) | Conductive interlayers or current collectors. | Excellent electrochemical stability and tunable conductivity, ideal for high-voltage cathode interfaces where stability is critical. |
| Nanodiamond Powder | Direct additive to SPEs (as referenced inspiration in the paper) to enhance mechanical modulus and Li$^{+}$ transport pathways. | Provides the high-modulus, inactive phase required to suppress dendrites, potentially exceeding the performance of molecular analogs like ADCN. |
Customization Potential
Section titled âCustomization Potentialâ6CCVDâs advanced manufacturing capabilities directly address the needs of scaling and optimizing ASSB components:
- Large-Area Diamond: We offer PCD plates/wafers up to 125mm in diameter, enabling the scale-up of SPE membrane research and the production of large-format battery components.
- Precision Thickness Control: We provide SCD and PCD layers with precise thickness control, from 0.1 ”m to 500 ”m, allowing engineers to optimize the mechanical strength and ion transport properties of diamond-enhanced interlayers.
- Custom Metalization: For integrating diamond layers into cell architecture (e.g., as current collectors or protective coatings), 6CCVD offers in-house metalization services including Au, Pt, Pd, Ti, W, and Cu deposition.
- Ultra-Low Roughness Polishing: Our SCD materials achieve surface roughness Ra < 1 nm, crucial for minimizing interfacial resistance (Rinterface) and ensuring uniform contact between the SPE and the electrode.
Engineering Support
Section titled âEngineering SupportâThe successful implementation of diamond-based materials requires specialized knowledge. 6CCVDâs in-house PhD team provides expert consultation for projects focused on All-Solid-State Battery (ASSB) Interfacial Engineering and High-Voltage Electrolyte Stabilization. We assist clients in selecting the optimal diamond material (SCD, PCD, or BDD) and geometry to maximize Li$^{+}$ conductivity, mechanical modulus, and electrochemical stability up to 6 V.
Call to Action: For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
Abstract The interfacial instability of the poly(ethylene oxide) (PEO)-based electrolytes impedes the long-term cycling and further application of all-solid-state lithium metal batteries. In this work, we have shown an effective additive 1-adamantanecarbonitrile, which contributes to the excellent performance of the poly(ethylene oxide)-based electrolytes. Owing to the strong interaction of the 1-Adamantanecarbonitrile to the polymer matrix and anions, the coordination of the Li + -EO is weakened, and the binding effect of anions is strengthened, thereby improving the Li + conductivity and the electrochemical stability. The diamond building block on the surface of the lithium anode can suppress the growth of lithium dendrites. Importantly, the 1-Adamantanecarbonitrile also regulates the formation of LiF in the solid electrolyte interface and cathode electrolyte interface, which contributes to the interfacial stability (especially at high voltages) and protects the electrodes, enabling all-solid-state batteries to cycle at high voltages for long periods of time. Therefore, the Li/Li symmetric cell undergoes long-term lithium plating/stripping for more than 2000 h. 1-Adamantanecarbonitrile-poly(ethylene oxide)-based LFP/Li and 4.3 V Ni 0.8 Mn 0.1 Co 0.1 O 2 /Li all-solid-state batteries achieved stable cycles for 1000 times, with capacity retention rates reaching 85% and 80%, respectively.