The design of Li-ion batteries with high energy storage capacities and efficiencies is a subject of increased research interest, being of key importance for their large-scale applications and further commercialization. However, conventional Li-ion batteries are expensive and have stability-related concerns, which limit their practical applications. In our search for cheaper and safer Li-ion batteries, we use a concentration gradient method to prepare LiNi_0.9Co_0.1–xTi_xO₂ (0.02 ≤ x ≤ 0.05) cathode materials surface-enriched with Co and Ti that exhibit decreased oxygen loss and improved structural stability. The corresponding crystal structures and morphologies are analyzed by X-ray diffraction and field emission scanning electron microscopy, with the Ni, Co, and Ti concentration distributions determined by energy-dispersive X-ray spectroscopy. The material with the best performance (x = 0.04) exhibits a discharge capacity of 214 mAh g⁻¹ in a charge/discharge voltage range of 3.0–4.3 V (vs. Li/Li⁺), and possesses an excellent 50-cycle capacity retention of 98.7%. Thermogravimetric analysis shows that partial substitution of Ni with the strongly oxophilic Ti solves the problem of oxygen loss observed in Ni-rich cathode materials such as LiNiO₂.

具有高能量存储容量和效率的锂离子电池的设计是日益引起研究兴趣的主题，这对于锂离子电池的大规模应用和进一步的商业化至关重要。然而，常规的锂离子电池昂贵并且具有与稳定性相关的问题，这限制了它们的实际应用。在我们的较便宜的，更安全的锂离子电池的搜索，我们使用了一个浓度梯度方法来制备的LiNi _0.9钴_0.1〜X的Ti _X Ô ₂（0.02≤  X ≤0.05）表面富含Co和Ti的阴极材料，它们显示出减少的氧损失和改善的结构稳定性。通过X射线衍射和场发射扫描电子显微镜分析相应的晶体结构和形态，并通过能量色散X射线光谱法确定Ni，Co和Ti的浓度分布。性能最佳（x  = 0.04）的材料在3.0-4.3 V（vs. Li / Li ^+）的充电/放电电压范围内的放电容量为214 mAh g ^-1），并具有98.7％的出色50循环容量保持率。热重分析表明，用强亲氧性Ti取代Ni可以解决在富Ni阴极材料（如LiNiO _2）中观察到的氧损失问题。