American PNNL uses mixed anode to extend lithium sulfur battery life

　　Author ：Iflowpower – Portable Power Station Supplier

Recently, the Northwest Pacific National Laboratory (PNNL) published by the US Department of Pacific said that they designed a mixed anode structure made of graphite and lithium to control the poor surface reaction of the lithium sulfur battery. Specifically, it is to add a layer of lithium hydroxide modified graphite in front of the lithium electrode, and such artificial protective layers can effectively reduce negative effects during the reaction. Researchers said: "Although the rechargeable lithium-ion battery is widely used in portable charging equipment and automotive electrification, they cannot store enough energy to meet the requirements of electric vehicles on renewal miles.

It is necessary to find theoretical alternative energy storage system than energy. In these techniques, lithium sulfur batteries are very promising. In theory, the specific capacity and energy distribution of lithium sulfur batteries are 1675mAhg-1,2600WHKG-1, which is much higher than ordinary lithium-ion batteries.

Sulfur has a rich reserve, non-toxic, making this idea attractive. However, there are still many problems in practical applications to solve. "Compared with ordinary lithium ion batteries, the energy density of lithium sulfur batteries is 2 to 3 times higher, and the maximum problem that limits the development of such batteries is that during the battery reaction, the flow of sulfides shortens the life of the battery.

About how to overcome sulfide flows, most of the previous research is committed to blocking sulfide leaks, but the difficulty is very difficult and obvious. "We envision, with it to protect the metal anode with an electrolyte additive or unreasonable barrier, perhaps we can design a completely different anode structure interface so that the interfacial oxidation reacts away from the metal surface. "Researchers said.

Lithium sulfur battery using conventional electrodes is only about 100 times, and this mixed anode can increase the cycle life of lithium sulfur batteries to 400 times. The researchers said that although the sulfide still flows, the battery life did not have a big impact, and during the experiment, the energy density of the lithium sulfur battery was only attenuated by 11%, and the coulomb efficiency was as high as 99%.