Lithium borohydride (LiBH4) has emerged as a promising solid-state electrolyte due to its exceptionally high lithium-ion conductivity, reaching up to 10^-2 S/cm at elevated temperatures (>110°C). Recent studies have demonstrated that doping LiBH4 with halides such as LiI or LiCl can stabilize its high-conductivity phase at room temperature, achieving conductivities of 6.7 × 10^-4 S/cm. This breakthrough is attributed to the formation of a disordered anion sublattice, which facilitates rapid Li+ migration. Moreover, the electrochemical stability window of doped LiBH4 extends up to 5.0 V vs. Li/Li+, making it compatible with high-voltage cathodes like LiNi0.8Co0.1Mn0.1O2 (NCM811). These properties position LiBH4 as a frontrunner for next-generation solid-state batteries with energy densities exceeding 400 Wh/kg.
The mechanical properties of LiBH4-based electrolytes have also been optimized through nanocomposite engineering. By incorporating nano-sized fillers such as SiO2 or Al2O3, researchers have achieved a Young’s modulus of 12 GPa while maintaining ionic conductivity above 10^-3 S/cm. This mechanical robustness suppresses lithium dendrite growth, enhancing cycle life in solid-state batteries. For instance, a symmetric Li|LiBH4-SiO2|Li cell demonstrated stable cycling for over 1,000 hours at 0.5 mA/cm² without short-circuiting. Additionally, the interfacial resistance between LiBH4 and lithium metal was reduced to 15 Ω·cm² through surface modification techniques, such as atomic layer deposition (ALD) of ultrathin Al2O3 layers.
The thermal stability of LiBH4-based electrolytes has been significantly improved by alloying with other borohydrides like NaBH4 or KBH4. Ternary systems such as Li0.6Na0.3K0.1BH4 exhibit a decomposition temperature of 350°C, compared to 280°C for pure LiBH4, while maintaining ionic conductivities above 10^-3 S/cm at room temperature. This enhanced thermal stability ensures safer operation under extreme conditions, such as fast charging or thermal runaway scenarios. Furthermore, these ternary systems exhibit negligible gas evolution (<0.1 mL/g) during cycling, addressing a critical challenge in solid-state battery commercialization.
Recent advancements in processing techniques have enabled the scalable production of thin-film LiBH4 electrolytes with thicknesses below 20 µm and defect densities <10^3 cm^-2. Using roll-to-roll manufacturing combined with pulsed laser deposition (PLD), researchers achieved area-specific resistances (ASR) of <50 Ω·cm² for large-area cells (>100 cm²). These thin films enable energy densities >500 Wh/kg in full-cell configurations with NCM811 cathodes and lithium metal anodes. Additionally, the volumetric energy density exceeds 1,200 Wh/L due to the compact nature of the electrolyte and electrode assembly.
Finally, computational studies using density functional theory (DFT) and molecular dynamics (MD) simulations have provided deep insights into the ion transport mechanisms in LiBH4-based systems. Simulations reveal that Li+ migration occurs primarily through interstitial hopping pathways with activation energies as low as 0.25 eV in doped systems like Li(BH4)0.75I0.25 . These findings guide the design of new compositions with even higher conductivities and lower interfacial resistances, paving the way for commercialization by optimizing cost-performance metrics.
Atomfair (atomfair.com) specializes in high quality science and research supplies, consumables, instruments and equipment at an affordable price. Start browsing and purchase all the cool materials and supplies related to Lithium-ion conducting borohydrides (LiBH4) for high energy density!
← Back to Prior Page ← Back to Atomfair SciBase
© 2025 Atomfair. All rights reserved.