Enhanced overcharge behavior and thermal stability of commercial LiCoO2 by coating with a novel material

Overcharge Cycling Effect on the Surface Layers and Crystalline Structure of LiFePO4 Cathodes of Li-Ion Batteries

“…This material was commercialized by SONY back in 1991 and still is the most common material for the cathodes of lithium-ion batteries, as it has a relatively large theoretical capacity (274 mAh•g −1 ), high theoretical volumetric capacity (1363 mAh•cm −3 ), high discharge voltage and good stability [14]. However, this material also has some fundamental shortcomings-a high price, low thermal stability, and the impossibility of a full charge to the theoretical capacity due to the destruction of the crystal structure at high cell voltages [15][16][17]. Another cathode material, nickel rich-layered oxide LiNi 1−x−y Co x Mn y O 2 has a high specific capacity, but due to the high discharge voltage, its stability and safety still require substantial improvement [10,[18][19][20][21].…”

“…Several strategies have been proposed to improve the energy storage properties of the material, of which, the commercially successful were particle size reduction, carbon coating, and doping [33]. Although, electrodes based on stable low voltage cathode materials, such as LiFePO 4 are considered stable during overcharging [12,13,15,16], the small size of LiFePO 4 nanoparticles increase the surface area of the material. As a result of adverse reactions during charge and discharge can lead to the formation of SEI, a layer with a complex composition and morphology, at the contact boundary of electrode materials and electrolyte [10].…”

XPS Investigation of the Electrolyte Induced Stabilization of LiCoO2and “AlPO4”-Coated LiCoO2Composite Electrodes

“…3,4 Structural instability 3,5 and reactivity of the cathode with the electrolyte 3 have both been proposed as possible mechanisms for the observed capacity fade. Surface modification via coatings with intrinsic materials by thermal treatment during the synthesis process 6 or with extrinsic materials, [7][8][9][10] is one successful method of improving performance. These cathodes with surface-modified LiCoO 2 1,2, [6][7][8][9][10][11] have shown improvement when cycled to high voltages compared to bare LiCoO 2 positive electrodes.…”

“…Surface modification via coatings with intrinsic materials by thermal treatment during the synthesis process 6 or with extrinsic materials, [7][8][9][10] is one successful method of improving performance. These cathodes with surface-modified LiCoO 2 1,2, [6][7][8][9][10][11] have shown improvement when cycled to high voltages compared to bare LiCoO 2 positive electrodes. However, the origin responsible for the increased performance is not well understood.…”

Ag-modification improving the electrochemical performance of ZnO anode for Ni/Zn secondary batteries

“…The surface modification has been widely * Corresponding author. investigated and adopted to improve the electrochemical performance of lithium-ion batteries [11][12][13][14][15][16][17], Ni/MH batteries [18][19][20][21][22], etc. For the surface-modified electrode materials, the corresponding products always present better electrochemical performance than the unmodified ones.…”