Pamidi Venkat, Trivedi Shivam, Behara Santosh, Fichtner Maximilian, Reddy M Anji
Helmholtz Institute Ulm (HIU) Electrochemical Energy Storage, Helmholtzstraße 11, 89081 Ulm, Germany.
Faculty of Science and Engineering, Swansea University, Fabian Way, Swansea SA1 8EN, UK.
iScience. 2022 Apr 4;25(5):104205. doi: 10.1016/j.isci.2022.104205. eCollection 2022 May 20.
Confining the particle-electrolyte interactions to the particle surface in electrode materials is vital to develop sustainable and safe batteries. Micron-sized single-crystal particles offer such opportunities. Owing to the reduced surface area and grain boundary-free core, particle-electrolyte interactions in micron-sized single-crystal particles will be confined to the particle surface. Here, we reveal the potential of such materials in sodium-ion batteries. We synthesized and investigated the chemical, electrochemical, and thermal properties of single-crystalline P2-type NaMnMgO as a cathode material for sodium-ion batteries. Single-crystalline NaMnMgO with a mean particle size of 8.1 μm exhibited high cycling and voltage stability. In addition, the exothermic heat released by the charged single-crystal NaMnMgO cathodes was four times lower than that of the corresponding polycrystalline NaMnMgO. This significantly enhances the thermal stability of electrode materials and possibly mitigates thermal runaways in batteries. Surprisingly, single crystals of NaMnMgO were relatively stable in water and ambient atmosphere.
将电极材料中颗粒与电解质的相互作用限制在颗粒表面对于开发可持续且安全的电池至关重要。微米级单晶颗粒提供了这样的机会。由于表面积减小且核心无晶界，微米级单晶颗粒中颗粒与电解质的相互作用将被限制在颗粒表面。在此，我们揭示了此类材料在钠离子电池中的潜力。我们合成并研究了作为钠离子电池阴极材料的单晶P2型NaMnMgO的化学、电化学和热性能。平均粒径为8.1μm的单晶NaMnMgO表现出高循环稳定性和电压稳定性。此外，带电的单晶NaMnMgO阴极释放的放热热量比相应的多晶NaMnMgO低四倍。这显著提高了电极材料的热稳定性，并可能减轻电池中的热失控现象。令人惊讶的是，NaMnMgO单晶在水和环境大气中相对稳定。
