The invention relates to a preparation method of a high-cycle and high-rate carbon-based negative
electrode energy storage composite material. The preparation method comprises the following steps: preparing
nickel salt hydrogel; preparing a dry gel precursor; transferring xerogel precursor particles into a tubular furnace, carrying out high temperature
calcination, and cooling the obtained calcined product; taking out the preliminarily calcined product,
grinding the preliminarily calcined product in a dry environment,
pickling the ground product, and
drying the pickled product; activating the dried calcined product under KOH
grinding and mixing; transferring the
potassium hydroxide ground and mixed product into the tubular furnace, and calcining the mixed product; naturally cooling the calcined mixed product to
room temperature; and
pickling the cooled product, washing the pickled product with
distilled water or
ethanol until the washed product is neutral, and
drying the neutral product to obtain the high-cycle and high-rate carbon-based negative
electrode energy storage composite material. Compared with other negative
electrode energy storage composite materials, the carbon-based negative electrode energy storage
composite material has the advantages of extremely high initial capacity, excellent cycle stability and good rate performance. The preparation method has the advantages of simplicity, low cost, excellent performances, and suitableness for producing large-scale commercial batteries.