Non-tubular-biomass-derived nitrogen-doped carbon microtubes for ultrahigh-area-capacity lithium-ion batteries.

The ever-increasing electric vehicles and portable electronics make lithium-ion barreries (LIBs) toward high energy density, resulting in long driving range and standby times. Generally, excellent electrochemical performance can be obtained in thin electrode materials with low mass loadings (<1 mg cm-2), but it is difficult to be achieved in commercial electrodes with high mass loadings (>10 mg cm-2). In this work, we report a facile method for fabricating nitrogen doped carbon microtubes (N-CMTs) consisted of crumped carbon nanosheets for high-performance LIBs with ultrahigh mass loading, where non-tubular biomass waste (i.e., peanut dregs) is employed as the precursor. Benefiting from the hollow tubular conductive network, high graphitization, and hierarchical structure, the as-synthesized N-CMTs exhibit ultrahigh area capacity of 6.27 mAh cm-2 at a current density of 1.5 mA cm-2 with a high mass loading of 15 mg cm-2 and superior cycling stability for LIBs. Our approach provides an effective strategy for the preparation of nitrogen-doped carbon microtubes to develope high energy LIBs with high mass loading electrodes.