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Discharging lithium-ion batteries to zero-charge state is one of the most reliable ways to avoid the thermal runaway during their transportation and storage. However, the zero-charge state causes the degradation or even complete failure of lithium-ion batteries. Specialized solutions are required to endow lithium-ion batteries with improved zero-charge storage performance, namely, the ability to tolerate zero-charge state for a long time without unacceptable capacity loss. Here, we report that a Li5FeO4 cathode additive can improve the zero-charge storage performance of LiCoO2/mesocarbon microbead (MCMB) batteries. The irreversible charge capacity of the Li5FeO4 additive results in the downregulation of anode and cathode potentials when the battery is at zero-charge state. More importantly, the Li5FeO4 additive offers a small discharge plateau below 2.9 V versus Li/Li+, which can hold the anode potential at zero-charge battery state (APZBS) in a potential range of 2.4∼2.5 V versus Li/Li+ during storage for 10 days. Such a precise control on APZBS not only suppresses the decomposition of the solid electrolyte interface film on the MCMB anode and inhibits the dissolution of the copper current collector occurring at high potentials but also avoids the excessive decrease of the cathode potential at the zero-charge battery state and consequently protects the LiCoO2 cathode from overlithiation occurring at low potentials. As a result, the Li5FeO4 additive with a charge capacity percentage of 23% in the cathode increases the capacity recovery ratio of the LiCoO2/MCMB battery from 37.6 to 95.5% after being stored at the zero-charge state for 10 days.

Truncated octahedral cuprous oxide (Cu 2 O) crystallites with highly uniform morphologies and sizes ranging from 2.4-2.5 µm were prepared by using a green and convenient approach and their antibacterial activities were studied. They were obtained through the chemical reduction of copper chloride by glucose in the presence of sodium hydroxide and polyethylene glycol at room temperature for 2 h. X-ray powder diffraction, energy dispersive spectrometer, scanning electron microscopy, and transmission electron microscopy as well as high-resolution transmission electron microscopy (HRTEM) were used to characterise the obtained products. Structural analysis revealed that these truncated octahedral crystallites were composed of eight {111} faces and six {200} faces. The effects of time, temperature and polyethylene glycol on the formation of truncated octahedral cuprous oxide were investigated. The possible growth process and mechanism of truncated octahedral cuprous oxide were proposed. The antibacterial activities of truncated octahedral Cu 2 O were also explored. They exhibited significant antimicrobial activity against both gram-negative and gram-positive bacteria. The result of antibacterial study revealed that the prepared Cu 2 O can be a promising candidate for wide range of bio-medical applications.