Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang, Sichuan, 621900, P. R. China.
Sichuan Research Center of New Materials, Chengdu, Sichuan, 610200, P. R. China.
Adv Mater. 2019 Jan;31(3):e1804439. doi: 10.1002/adma.201804439. Epub 2018 Nov 25.
The rapid development of wearable electronics requires a revolution of power accessories regarding flexibility and energy density. The Li-CO battery was recently proposed as a novel and promising candidate for next-generation energy-storage systems. However, the current Li-CO batteries usually suffer from the difficulties of poor stability, low energy efficiency, and leakage of liquid electrolyte, and few flexible Li-CO batteries for wearable electronics have been reported so far. Herein, a quasi-solid-state flexible fiber-shaped Li-CO battery with low overpotential and high energy efficiency, by employing ultrafine Mo C nanoparticles anchored on a carbon nanotube (CNT) cloth freestanding hybrid film as the cathode, is demonstrated. Due to the synergistic effects of the CNT substrate and Mo C catalyst, it achieves a low charge potential below 3.4 V, a high energy efficiency of ≈80%, and can be reversibly discharged and charged for 40 cycles. Experimental results and theoretical simulation show that the intermediate discharge product Li C O stabilized by Mo C via coordinative electrons transfer should be responsible for the reduction of overpotential. The as-fabricated quasi-solid-state flexible fiber-shaped Li-CO battery can also keep working normally even under various deformation conditions, giving it great potential of becoming an advanced energy accessory for wearable electronics.
可穿戴电子设备的快速发展需要在灵活性和能量密度方面对电源配件进行革命。最近提出了 Li-CO 电池，作为下一代储能系统的新型有前途的候选者。然而，目前的 Li-CO 电池通常存在稳定性差、能量效率低和液体电解质泄漏等问题，迄今为止，很少有用于可穿戴电子设备的柔性 Li-CO 电池得到报道。在此，通过采用负载在碳纳米管（CNT）布上的超细 Mo C 纳米粒子的自支撑混合薄膜作为正极，展示了具有低过电势和高能量效率的准固态柔性纤维状 Li-CO 电池。由于 CNT 基底和 Mo C 催化剂的协同作用，它实现了低于 3.4 V 的低充电电位、约 80%的高能量效率，并可以可逆地放电和充电 40 次。实验结果和理论模拟表明，通过配位电子转移稳定的 Mo C 中间放电产物 Li C O 应该是降低过电势的原因。所制备的准固态柔性纤维状 Li-CO 电池即使在各种变形条件下也能正常工作，这使其有望成为用于可穿戴电子设备的先进能源配件。
