Nickel-rich layered materials LiNi0.8Co0.1Mn0.1O2 (NCM) is a promising candidate cathode material for next generation lithium-ion battery due to its high energy density and relatively low cost. Unfortunately, NCM suffer from...

No abstract

Recycling of spent lithium-ion batteries is of great importance for environmental protection and resusing resources. This work proposes a green and environmentally friendly recycling strategy of LiNi 1/3 Co 1/3 Mn 1/3 O 2 cathode material for spent batteries by an electrochemical method. In the designed electrolysis cell, the produced gaseous species from oxidation of solvent molecules occurring at the interfaces between electrode/cathode materials and active particles/binder exert the force to separate bonded particles from current collector. Meanwhile, the efficient leaching of lithium (>98%) into electrolyte was achieved under an electric field without additional leaching process. The Al can also be recovered in the form of metallic foil. The separation of active material, the selective leaching of lithium, and recovery of Al foil are conducted by one-step electrolysis in a short operating cycle. The remaining transition metals in residues were reused to synthesize LiNi 1/3 Co 1/3 Mn 1/3 O 2 material. As the cathode material, the regenerated active material delivers an initial capacity of 161 mAh g −1 at 0.1 C and 88.3% remains after 200 cycles. The superior cycling stability is comparable to the unused commercial batteries. This innovative approach can be readily extended to recover other types of cathode materials for spent lithium-ion batteries.

A three dimensional (3D) Al2O3 coating layer was synthesized by a facile approach including stripping and in situ self-assembly of γ-AlOOH. The uniform flower-like Al2O3 nanosheets with high specific area largely sequesters acidic species produced by side reaction between electrode and electrolyte. The inner coating layer wrapping spinel LiMn2O4 effectively inhibits the dissolution of Mn by suppressing directive contact with electrolyte to enhance cycling stability. The rate performance is improved because of the better electrolyte storage of the assembled hierarchical architecture of the 3D coating layer affording unimpeded Li(+) diffusion from electrode to electrolyte. The electrochemical results reveal the as-prepared coated LiMn2O4 sample with the amount of Al2O3 at 1 wt % exhibits superior cycle stability under room temperature even at elevated temperature. The initial specific discharge capacity is 128.5 mAh g(-1) at 0.1 C and retains 89.8% of the initial capacity after 800 cycles at 1 C rate. When cycling at 55 °C, the composite shows 93.6% capacity retention after 500 cycles. This facile surface modification and effective structure of coating layer can be adopted to enhance the cycling performance and thermal stability of other electrode materials for which Al2O3 plays its role.

No abstract