Progress of material coating repair technology for failed graphite anode

With the rapid development of new energy automobile industry, the demand for large capacity, high performance battery is rising rapidly, lithium battery is widely used in new energy automobile field because of its high energy density, long cycle life, low self-discharge rate and other advantages. Accompanied by the large number of lithium batteries, the demand for graphite anode is rising rapidly. As a key component of lithium batteries, graphite has become the most dominant anode material in commercial lithium batteries by virtue of its lower cost, higher energy density, excellent electrical conductivity and good cycle stability. However, as the number of lithium battery cycles increases, solid electrolyte (SEI) interface layer and lithium dendrites will gradually form on the surface of graphite anode, leading to the damage of graphite structure and the decrease of electrochemical performance, which will lead to a large amount of wasted graphite resources. In order to achieve the sustainable development of graphite, we need to regenerate and repair the failed graphite anode and put it into trial again. In this paper, we review the progress of the application of material coating technology in the repair of failed graphite anode, we briefly introduce the decontamination methods of failed graphite anode, and then we focus on the repair of failed graphite anode by three methods, namely, asphalt coating repair, metal oxide coating repair and polymer coating repair. These coating techniques can effectively repair the damaged structure of the failed graphite and restore its electrochemical performance. Finally, this paper puts forward the challenges faced by the current material capping technology and puts forward an outlook on the future research direction to promote the sustainable development of the new energy battery industry.