Preparation method of lithium-philic carbon nanotube paper and preparation method of composite metal lithium negative electrode

Abstract

The invention provides a preparation method of lithium-philic carbon nanotube paper. The preparation method specifically comprises the following steps: uniformly mixing carbon nanotube powder and lithium-philic nano material powder, and carrying out papermaking to form a film by using a wet papermaking process. In order to improve the film strength under low thickness, nanocellulose can be added,then the film is heated in an inert gas environment to enable the lithium-philic nano material and the carbon nano tube to be tightly combined, and the nanocellulose is carbonized to form the carbon nano fiber with the lithium-philic surface. According to the prepared lithium-philic carbon nanotube paper, better chemical contact exists between the lithium-philic nano material and the carbon nanotubes, and the lithium-philic nano material in the carbon nanotubes is wide in dispersion and stable in deposition; the lithium metal negative electrode prepared by the method has the effects of inhibiting lithium dendritic crystal growth and modifying solid electrolyte interface film components, and also has the effects of providing space for lithium metal deposition, reducing the nucleation barrier of lithium deposition, remarkably improving the cycle stability of the lithium metal negative electrode and prolonging the cycle life of the lithium metal negative electrode.

Description

technical field [0001] The invention belongs to the technical field of secondary batteries, and in particular relates to a preparation method of lithium-friendly carbon nanotube paper and a preparation method of a composite metal lithium negative electrode. Background technique [0002] Since the 21st century, mobile electronic information products have developed rapidly, and the capacity requirements for energy storage batteries have become increasingly stringent. The energy density of traditional lithium-ion batteries is close to the upper limit, making it difficult to meet the needs of 3C products. Li metal anode has attracted extensive attention due to its ultra-high specific capacity of 3860mAh / g and the lowest reduction potential of -3.04V. However, metal lithium anodes have been difficult to be applied in practice so far, mainly because of the problems of dendrite growth and low Coulombic efficiency during the battery cycle: on the one hand, lithium ion deposition is ...

AI Technical Summary

Problems solved by technology

However, metal lithium anodes have been difficult to be applied in practice so far, mainly because of the problems of dendrite growth and low Coulombic efficiency during the battery cycle: on the one hand, lithium ion deposition is greatly affected by the current density, the larger the current, the more lithium ion deposition Faster, the more conducive to the growth of dendrites, until it pierces the separator to cause an internal short circuit in the battery, there is a danger of battery combustion explosion; on the other hand, lithium metal has strong chemical activity, and will continue to have side reactions with the electrolyte, resulting in low Coulombic efficiency

In addition, metal foam or carbon fiber is relatively hard, which is easy to pierce the separator and cause a short circuit of the battery, which poses a potential safety risk