High-energy-storage power battery and preparation method

Abstract

The invention discloses a high-energy-storage power battery and a preparation method thereof. The high-energy-storage power battery is formed by assembling a positive electrode part, a negative electrode part, electrolyte and a diaphragm. The positive electrode part, the diaphragm and the negative electrode part are sequentially arranged from bottom to top, and the positive electrode part comprises a positive electrode piece protective layer, a positive electrode active substance layer and a positive electrode piece which are sequentially stacked from bottom to top. The negative electrode partcomprises a negative electrode plate, a negative electrode active material layer and a negative electrode plate protective layer which are sequentially stacked from bottom to top, the positive electrode plate comprises a positive electrode part base material and a carbon composite material, the negative electrode plate comprises a negative electrode part base material and a carbon composite material, and the positive electrode active material layer comprises lithium nickel cobalt manganate, lithium iron phosphate and high-specific-volume tantalum powder. The negative electrode active materiallayer includes a carbon-silicon composite material. The high-energy-storage power battery disclosed by the invention can achieve the effects of no short-circuit fault, no melting combustion fault andno burning explosion fault, the charging target value is more than 85% of the rated capacity within 15-30 minutes, and the minimum charging and discharging cycle is more than 3000 times.

Description

technical field [0001] The invention relates to the technical field of electrochemistry, in particular to a high energy storage power battery and a preparation method. Background technique [0002] Clean energy such as solar energy and wind energy is widely used around the world and is the main form of next-generation energy utilization, but their disadvantage is the intermittent energy supply problem; energy storage for field facilities (such as communication base stations) is also an urgent problem to be solved. Therefore, it is particularly important to find energy storage devices with high specific capacity. On the other hand, with the strengthening of people's awareness of environmental protection and the continuous consumption of fossil non-renewable resources, it has become an inevitable trend of development for electric vehicles to replace traditional vehicles, which also increases the demand for high energy density and high power density power batteries. [0003] M...

AI Technical Summary

Problems solved by technology

Although the volume expansion problem of silicon has been solved, the efficiency of the first charge and discharge has not been effectively improved

Publication No. CN109686941A "A Method for Preparing Silicon-Carbon Negative Material for Lithium-ion Power Batteries" uses the activity of magnesium powder to reduce silicon oxide by ball milling, and compound-coats the composite material obtained by ball milling through the hydrothermal reaction of glucose aqueous solution After treatment, the obtained electrode material maintains a high capacity level in a long cycle, but silicon still has the problem of volume expansion during the charging and discharging process of the battery.

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