Advanced Metal Oxide@Carbon Nanotubes for High‐Energy Lithium‐Ion Full Batteries

Abstract

A strategy to synthesize a Fe3O4@carbon nanotube (CNT) composite with high tap density of 1.22 g cm−3 and electronic conductivity of 4.1 S cm−1 is developed. The Fe3O4@CNT composite exhibits an extremely high capacity of over 1263 mAh g−1, even after 125 cycles at a current density of 100 mA g−1. Additionally, a lithium‐ion full battery of Fe3O4@CNT|LiNi0.5Mn1.5O4 with an energy density of 2283 Wh kganode−1 (381 Wh kgcathode−1) is successfully configured. After optimization of the work voltage windows and electrolyte additives, it has a capacity retention of 71 % after more than 400 cycles. Using this synthetic strategy, additional metal oxide@CNT (e.g., Co3O4, MnO2, CuO, ZnO) composites with high lithium storage capability are explored, and their electrochemical differences versus the cathode of LiNi0.5Mn1.5O4 are investigated in light of their superior performances. Applying this type of metal oxide‐based composite in full cells is a significant step to the development of high‐energy lithium‐ion batteries and to further applications in current sodium‐ion batteries.

X‐ray Nano‐computed Tomography of Electrochemical Conversion in Lithium‐ion Battery

“…Recently, synthetic approaches capable of retaining structural integrity and ensuring electrode stability for nanostructured metal oxides have been developed, which has only partly mitigated the voltage hysteresis issue . Indeed, the complex‐displacement reaction pathway involving massive electrode reorganization actually affects the electrochemical potential stability upon prolonged cycling and leads to capacity decay, thus limiting the practical application of metal oxide anodes …”

“…[16,[23][24][25][26] Indeed, the complexdisplacementr eaction pathway involving massive electrode reorganization actually affects the electrochemical potential stability upon prolonged cycling and leads to capacity decay, [24,27] thus limiting the practical application of metal oxide anodes. [28,29] Herein, an anometric CuO anode for lithium-ion batteries was investigated by combining electrochemical measurements and ex situ X-ray computedt omography (CT) at the nanoscale. The electrode reactedb yc onversion at about 1.2 and 2.4 Vv ersus Li + /Li during discharge and charge, respectively,t od eliver a capacityr anging from 500 mAh g À1 to over 600 mAh g À1 .…”

Preparation of CuO@PPy hybrid nanomaterials as high cyclic stability anode of lithium‐ion battery

“…Fabricate coreshell structure can enhance lithium ion battery cycling stability as the shell on the surface can prevent the powdered material detached from the Cu foil collector. The shell structure such as carbon coating [14], graphene hybrid [15], conductive polymer film coating [5], inorganic metal oxides coating except copper oxide etc. can cushion the structural stress of CuO led by the duplicate lithiation/ delithiation.…”

Bioinspired Architectures and Heteroatom Doping To Construct Metal‐Oxide‐Based Anode for High‐Performance Lithium‐Ion Batteries

“…The capacity of MnO/N−C is much higher than the theoretical value of 756 mAh g −1 for MnO, which should benefit from the lithium‐storage capability within the spaces of the nanostructures. The fine (dis‐)charge curves of MnO/N−C are presented in Figure b, in which the increased capacity may result from the activation of MnO during the cycling for the repeated (de‐)lithiiation . One interesting phenomenon we have found is that the bare MnO has no increment trend in capacity compared to that of MnO/N−C.…”