Application of magnesium oxide in batteries

Hebei Messi Biology Co., Ltd. stated that magnesium oxide is a well-known inorganic material. It is a very common alkaline oxide and the main raw material for the production of magnesium hydroxide and magnesium metal. However, with the upgrading of industrialization and the demand and development of the high-tech functional materials market, fine magnesium oxide products, especially nano-magnesium oxide, have begun to receive the attention of various industries.

As for whether magnesium oxide has any application in the battery industry? The answer is yes, and its effect is neither great nor small. Since nanoscale magnesium oxide is a new type of nanomaterial, it has obvious small size, large surface effect, quantum size effect and macro tunnel effect. The surface has been modified without agglomeration, and has better dispersion and better dispersion in the system. Nano-active, it can give full play to the light, electricity, magnetic field, thermal and quantum effects of nano-magnesium oxide particles, greatly improving the performance of products added with nano-magnesium oxide – so nano-magnesium oxide is often used in battery materials. Improve the battery’s cycleability and charge-discharge times, and extend the battery’s service life. Let’s take a look at the specific application conditions below.

1Applications in lithium batteries

The high-capacity tin composite negative electrode material of lithium-ion battery is selected to add 10-100g/L of insoluble solid particles such as SiO2, TiO2, ZrO2, Cr2O3, Fe2O3, CeO2, MgO, SiC, and BaSO with a diameter between 0.05 and 10 microns; this method The prepared nickel-solid particle-tin composite negative electrode material has high specific capacity, high first charge and discharge efficiency, and stable cycle performance as a negative electrode for lithium ion batteries.

By adding an appropriate amount of nano-magnesium oxide to the lithium-ion battery cathode material, the resulting cathode material has a reversible discharge capacity of greater than 140mAh/g and has good cycle performance. Used in cathode materials to improve conductivity, the recommended addition amount is 0.3-0.5%.

②Cathode material dopant

Using nano-magnesium oxide as a conductive dopant, a magnesium-doped lithium iron manganese phosphate is prepared through a solid-state reaction, which further produces a nanostructured cathode material with a conductivity of up to 10-2S/cm and an actual discharge capacity of 240mAh/ g. This new cathode material has the characteristics of low price, high energy and safety. It is not only suitable for small and medium-sized polymer, colloidal and liquid lithium-ion batteries, but is especially suitable for high-power power batteries.

Magnesium oxide can also optimize the capacity and cycle performance of spinel lithium manganate batteries. In the lithium-ion battery electrolyte using spinel lithium manganate as the cathode material, nano-magnesium oxide is added as a deacidification agent to remove acid, and the addition amount is 0.5-20% of the weight of the electrolyte. By removing acid from the electrolyte, the content of free acid HF in the electrolyte is reduced to less than 20 ppm, which reduces the dissolving effect of HF on LiMn2O4 and improves the capacity and cycle performance of LiMn2O4.

Nano-magnesium oxide can be added to a mixed aqueous solution containing cobalt salt and nickel salt to co-precipitate Ni-Co composite hydroxide. The specific steps are to add lithium hydroxide to the composite hydroxide, heat-treat the mixture at 280~420°C, and then heat-treat the product obtained in the above steps at 650~750°C. When this lithium composite oxide is used as an anode active material, a high-capacity lithium ion secondary battery can be obtained. The addition amount of nano magnesium oxide is about 5%.

2Applications in zinc-nickel batteries

Incorporating magnesium oxide into the zinc negative active material through physical mixing can reduce charge and discharge polarization, reduce internal resistance in the late cycle, improve the utilization rate of the negative plate active material, and extend the battery cycle life. The appropriate addition amount is 1.0%wt of magnesium oxide, and the addition amount should not exceed 2.0%.

3Applications in high chloride zinc batteries

Adding a small amount of magnesium oxide to the positive active material can adjust the acidity of the electrolyte, slow down self-discharge, inhibit battery swelling, improve storage performance, and has unique effects on increasing discharge capacity and promoting slurry gelatinization. It is recommended to add 0.5-1% and adjust the appropriate pH value.

4Applications in cadmium-nickel batteries

Adding appropriate amounts of magnesium oxide, zinc oxide and iron oxide to cadmium electrodes can improve the utilization rate of active materials; adding magnesium oxide, indium trioxide and zinc oxide can improve the charge retention capacity of sealed cadmium-nickel batteries.