基于三维导电膜的锌镍电池及其在智能门锁上的应用

Zinc-nickel battery based on a 3D conductive film and its application in intelligent lock

锌镍电池是非常有发展前景的绿色储能技术,然而,由于锌负极形变、枝晶生长、钝化、严重的副反应等问题,影响了锌镍电池的大规模应用。本工作采用氧化还原石墨烯(rGO)、科琴黑(KB)和碳导电膜(CCF),通过喷涂技术制备了具有三维导电网络的CCF@KB-rGO膜,采用该三维导电膜的AA型锌镍电池展现出良好的电化学性能。超支化KB和层状rGO形成三维的导电网络,提高了电子和离子的传导能力,使锌镍电池具有良好的快速充电和低温放电性能,充电80%仅需要43分钟,-20℃条件下0.5 C可以放出60%以上额定容量;层状rGO有助于锌负极的均匀沉积,提高了电池的循环稳定性,经过300次循环,锌负极没有发现明显的枝晶;CCF@KB-rGO中高比表面积的KB和rGO可以吸附部分游离的电解液,抑制了锌负极溶解,同时降低了电池的自放电。采用CCF@KB-rGO的AA锌镍电池电化学性能突出,安全性好,各方面的表现均优于一次性干电池,更好地满足了智能门锁对电池性能不断提高的要求。本工作基于三维导电膜的设计有效提高了锌镍电池性能,为锌镍电池的研究提供了新的思路。

Zinc-nickel battery(ZNB)is regarded as a prospective green-energy storage technology.However,the large-scale application of ZNB is impeded by the deformation,dendrite growth,passivation,and serious side reactions of the zinc anode.In this study,reduced graphene oxide(rGO),Ketjenblack(KB),and carbon conductive film(CCF)are used to prepare the CCF@KB-rGO film with three-dimensional(3D)conductive network based on the spraying technology.The results show good electrochemical performance by AA ZNBs with CCF@KBrGO.The hyperbranched KB and layered rGO form a 3D conductive network to enhance electron and ion conduction,thus improving the fast charge and low temperature-discharge performance of ZNB.Furthermore,an 80%capacity charge could be achieved within 43 min,and more than 60%rated capacity is output at 0.5 C at-20℃.The layered rGO enables zinc to be deposited uniformly and improves the cycle stability of the zinc anode;no obvious dendrites are found in the zinc anode after 300 cycles.The KB and rGO with high specific-surface area in CCF@KBrGO can adsorb part of the free electrolytes,thus inhibiting the dissolution of the zinc anode and reducing the self-discharge of the battery.The outstanding electrochemical performance and safety of the AA ZNB with CCF@KB-rGO is far better than that of a disposable dry battery in the application of intelligent locks.Thus,the ever-growing requirements of smart lock are met for battery performance.The design based on the proposed 3D conductive film improves the performance of ZNB effectively,thus providing a new idea for the research of ZNBs.