Self-healing lithium battery anode material is used for high energy density lithium battery

As part of the ongoing development of battery technology, a large number of anode studies are being conducted around the world. One of the ideas was to replace the commonly used graphite with anodic lithium metal, which may be due to a significant increase in some of the research at Rensselaer Polytechnic Institute in New York.

The competition for much better energy density has been more than a decade and seems to be getting stronger. The battery density has become better and the price has dropped, but there is a lot of room for improvement. These breakthroughs are mainly through the use of different chemicals, but sometimes only to improve known chemicals, including some known chemicals, which provide high energy density (ideal in electric vehicles because it means the same weight) More mileage, or the same mileage is at a lower weight).

One of the biggest challenges of certain battery chemistries is the deterioration and loss of energy storage capacity due to dendrite build-up - which prevents researchers from extruding enough life from the battery to gain commercial competitiveness. A potential new solution is to use heat to self-heal the lithium metal battery, which eliminates dangerous dendrite buildup in the anode. The accumulation of dendrites on the lithium metal electrode reduces efficiency and ultimately causes the battery to "wear", using non-technical terms. As the battery is charged and discharged, a tree structure is formed. The faster the dendrites accumulate, the lower the energy storage capacity of the battery is acceptable to the consumer. Think of it as a plaque on your teeth - the longer you leave it, the more likely it is to create cavities and shorten the "useful life" of the teeth.

According to an article at the Green Car Conference, the new heating solution causes the lithium dendrites to fuse and fuse into a uniform (smooth) surface. This also eliminates the risk of electrical shorts in the battery and battery pack. More here:

Although lithium (Li) metal electrodes have extremely high energy densities, they have not yet been deployed in commercial rechargeable batteries because electrochemical plating and stripping always lead to dendrite growth, which reduces coulomb efficiency and ultimately leads to battery short circuits. Many methods have been proposed to eliminate dendrite formation.

Now, a team at Rensselaer Polytechnic Institute (RPI) has basically taken the opposite approach. The researchers increased the current density (charge-discharge rate) of the cell, which led to widespread self-heating of the resulting dendrites, leading to surface diffusion of lithium - in other words, diffusing the dendrites to a uniform layer. Their work papers are published in the journal Science.

Lu Li, one of the original researchers, explained: "People generally believe that dendrite problems will increase at high current densities. Here, we report a tree-like evolutionary mechanism, which in turn is correct. In our experiment in the middle, we found that when the plating and stripping current density is increased to more than 9 MA per square centimeter, the dendrites will have a large amount of self-heating, which leads to extensive surface migration of Li. This surface diffusion cures dendrites and smoothes Lithium metal surfaces. We show that repeated doses of high current density healing treatments can provide high coulomb efficiency for safe cycling of lithium-sulfur batteries."

Technically, by using the internal resistance heating of the battery (also known as Joule heating), which is the result of the metal material resisting current flow and you can smooth the dendritic grains - as evidenced by the proof of concept using lithium battery.

We have been used to the breakthrough of batteries for many years. The frantic pace of development has made the oil industry feel ashamed and has provided billions of dollars in funding every year, which is an elusive fuel source.

In the past decade, lithium batteries have assumed the main motor dynamic load, and their exotic chemicals continue to imply more performance and longevity. The self-healing lithium metal anode seems to be another positive development.

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