Poizot P, Laruelle S, Grugeon S, Dupont L, Tarascon J M
Laboratoire de Réactivité et Chimie des Solides, Université de Picardie Jules Verne, CNRS UPRES A 6007, Amiens, France.
Nature. 2000 Sep 28;407(6803):496-9. doi: 10.1038/35035045.
Rechargeable solid-state batteries have long been considered an attractive power source for a wide variety of applications, and in particular, lithium-ion batteries are emerging as the technology of choice for portable electronics. One of the main challenges in the design of these batteries is to ensure that the electrodes maintain their integrity over many discharge-recharge cycles. Although promising electrode systems have recently been proposed, their lifespans are limited by Li-alloying agglomeration or the growth of passivation layers, which prevent the fully reversible insertion of Li ions into the negative electrodes. Here we report that electrodes made of nanoparticles of transition-metal oxides (MO, where M is Co, Ni, Cu or Fe) demonstrate electrochemical capacities of 700 mA h g(-1), with 100% capacity retention for up to 100 cycles and high recharging rates. The mechanism of Li reactivity differs from the classical Li insertion/deinsertion or Li-alloying processes, and involves the formation and decomposition of Li2O, accompanying the reduction and oxidation of metal nanoparticles (in the range 1-5 nanometres) respectively. We expect that the use of transition-metal nanoparticles to enhance surface electrochemical reactivity will lead to further improvements in the performance of lithium-ion batteries.
长期以来，可充电固态电池一直被认为是适用于各种应用的有吸引力的电源，特别是锂离子电池正成为便携式电子产品的首选技术。这些电池设计中的主要挑战之一是确保电极在多次充放电循环中保持其完整性。尽管最近已经提出了有前景的电极系统，但其寿命受到锂合金团聚或钝化层生长的限制，这阻止了锂离子完全可逆地插入负极。在此我们报告，由过渡金属氧化物纳米颗粒（MO，其中M为Co、Ni、Cu或Fe）制成的电极展现出700 mA h g⁻¹的电化学容量，在高达100次循环中容量保持率为100%，且具有高充电速率。锂反应的机制不同于经典的锂插入/脱插或锂合金化过程，并且涉及Li₂O的形成和分解，分别伴随着金属纳米颗粒（1至5纳米范围内）的还原和氧化。我们预计，使用过渡金属纳米颗粒来增强表面电化学反应性将导致锂离子电池性能的进一步改善。
