Given the fast-growing demand for lithium-ion batteries (LIBs) and the upcoming climax of LIB retirement, efficient recycling of spent LIBs has shown increasing importance in both economic benefit and environmental conservation. The LIBs with LiFePO4 (LFP) cathodes account for half of the LIB market, so developing an appropriate recycling way for spent LFP (SLFP) batteries is imperative. In this work, a closed-loop regeneration of SLFP cathodes is proposed, in which a facile cold stimulation route is invented to peel the SLFP layer from Al foil, and then Li and Fe elements are selectively and efficiently extracted from the peeling SLFP layer under mild conditions based on an oxidant of NaClO. The leaching rate of elemental Li could reach 98.3%, and the regenerated LFP synthesized by recovered Li2CO3 and FePO4 shows exceptional performance with a discharge capacity of 162.6 mAh g-1 at 0.5 C. This regeneration route has greatly reduced the use of chemical reagents, shortened the process of impurity removal, and, therefore, realized the closed-loop regeneration of SLFP batteries.
Haichuan Peng,Yan Zhou,Chuxi Zhang,Manyu Wang,Siyu Zhao,Yingying Xu,Wei Zhang,Hongbo Xin,Xiaolei Wang
Obesity is a chronic and recurrent disease with potential risks. Traditional weight-loss methods (like exercises, surgeries, oral drugs, etc.) have shown different side effects. In this experiment, the microneedle (MN) patch was selected as the drug carrier of the weight-loss drug Rosiglitazone (Rosi). Besides, melanin was added to enhance the photo-thermal effect and accelerate the release of drugs to the target fat region under near-infrared (NIR) light. Afterwards, with exterior cold stimulation, the significant and accurate effect of body slimming could be achieved. This combination of soluble MN patches and variable temperatures provides an attractive nonsurgical method for future accurate body slimming management.