Lithium-ion batteries can be recharged during use and are a type of secondary rechargeable battery. The main working principle is the repeated movement of lithium ions between the positive and negative electrodes. Regardless of the shape of the battery, its main components are electrolyte, positive electrode sheet, negative electrode sheet and separator. At present, the production sites of lithium-ion batteries in the world are mainly concentrated in China, Japan and South Korea, and the main lithium-ion application markets are mobile phones, computers and Electric Vehicles.
With the continuous development of lithium-ion batteries, the application field is also gradually expanding. Its use of positive electrode materials has changed from single to diversified, including: olivine-type lithium iron phosphate, layered lithium cobalt oxide, spinel lithium manganese oxide, etc., to achieve the coexistence of multiple materials.
Nano magnesium oxide (VK-Mg30D) is a new type of nanoparticle material with a white powder appearance, high purity, large specific surface area, and composed of fine grains. It has obvious small size effect, surface effect, quantum size effect and macro tunnel effect. There is no gas in the electrode, the surface is easy to regenerate, the hydrogen and oxygen overpotential is small, and the price is cheap. Therefore, it is widely used.
A brief introduction to adding nano magnesium oxide (VK-Mg30D) to lithium batteries:
1. Lithium-ion batteries choose to add 10-100g/L of insoluble solid particles such as TiO2, SiO2, Cr2O3, ZrO2, CeO2, Fe2O3, BaSO4, SiC, MgO with a diameter between 0.05-10μm, and the prepared materials have the characteristics of good charge and discharge efficiency, high specific capacity, and stable cycle performance as lithium ions.
2. Lithium battery positive electrode material, using nano magnesium oxide (VK-Mg30D) as a conductive dopant, through solid phase reaction to generate magnesium-doped lithium iron manganese phosphate, and further made into nanostructured positive electrode materials, its conductivity can reach 10-2S/cm, and the actual discharge capacity reaches 240mAh/g. This new positive electrode material has the characteristics of high energy, environmental protection, and low price, and is suitable for liquid and colloidal lithium-ion batteries, small and medium-sized polymers, especially for high-power power batteries.
3. Optimize the capacity and cycle performance of spinel lithium manganese oxide batteries. In the electrolyte of lithium-ion batteries using spinel lithium manganese oxide as the positive electrode material, nano magnesium oxide (VK-Mg30D) is added as a deacidifying agent for deacidification, and the addition amount is 0.5-20% of the weight of the electrolyte. By deacidifying the electrolyte, the content of free acid HF in the electrolyte is reduced to below 20ppm, reducing the dissolution of HF on LiMn2O4, and improving the capacity and cycle performance of LiMn2O4.
4. Nano magnesium oxide (VK-Mg30D) is mixed with an alkaline solution as a pH regulator and an ammonia solution as a complexing agent, and added to a mixed aqueous solution containing cobalt salt and nickel salt to coprecipitate Ni-CO composite hydroxide. Lithium hydroxide is added to the Ni-CO composite hydroxide, and the mixture is heat-treated at 280-420°C. The resulting product is heat-treated in an environment of 650-750°C. Depending on the coprecipitation time, the average particle size of the lithium composite oxide is reduced or the stacking density is increased. When lithium composite oxide is used as the anode active material, a high-capacity lithium-ion secondary battery can be obtained, and the actual amount of nano magnesium oxide (VK-Mg30D) added depends on the specific formula.
With the promotion and use of nano magnesium oxide, our ecological environment can be significantly improved and energy conservation can be achieved, which is of great significance to the country’s long-term development.