401030 polymer battery.The United States develops P2S5 electrolyte additive for lithium-sulfur batteries

　　According to foreign media reports, recently, researchers at the University of Texas at Austin developed a new electrolyte additive. A scientific research team led by Professor Arumugam Manthiram found that by using phosphorus pentasulfide (P2S5) as an electrolyte additive, commercialized Li2S particles can be directly used as high-capacity cathode materials for lithium-sulfur batteries, without the need for complicated synthesis or Use a rechargeable termination voltage (resulting in reduced electrolyte stability and safety). The large-scale use of commercialized particles can significantly reduce the production cost of lithium-sulfur batteries using lithium-sulfur as the cathode. The paper was published in the American Chemical Society's Journal of Physical Chemistry Letters. The researchers pointed out in the paper that this discovery is of great significance to the safe and efficient use of Li2S as a battery cathode material and the manufacture of low-cost, lithium-free lithium-sulfur batteries. The theoretical capacity of lithium-sulfur batteries is very high, reaching ∼2500Whkg−1, and requires the use of lithium metal as the anode. However, lithium metal will gradually degrade in the battery anode and affect the safety and performance of the battery. An alternative is to connect a lithium-free battery anode (such as tin and silicon) to a lithium sulfide cathode (∼1166mAhg−1). Studies have confirmed that using lithium sulfide has great difficulties in the initial charging stage, which is related to the accumulation of new polysulfide compounds. The voltage barrier can be solved by using a termination voltage in the early stages of charging, but this will cause instability in the commonly used ether-based electrolyte and a degradation of the battery's electrochemical performance. The researchers compared the performance of lithium-sulfur cathode in electrolyte and P2S5 in CR2032 button battery. By comparison, the reversible discharge capacity of lithium sulfur anode is ∼800mAhg−1. After 80 times of charge and discharge, the capacity can still be as high as 83%, and the Coulombic efficiency is still close to 100%. The researchers concluded that the interaction between P2S5 and Li2S will cause the tank resistance to decrease, accelerate the oxidation of Li2S into polysulfide compounds, and greatly reduce the voltage plateau of the initial charge. The researchers added that when the molar ratio of Li2S and P2S5 is 7:1, the most efficient electrochemical reaction occurs before a thick layer of solid electrolyte is generated on the surface of Li2S. Since the core structure of P2S5 is activated, micron-level Li2S will be retained when activation occurs, and activation is only a surface effect.

Read recommendations:

R20

Water lithium battery.LR754 battery

What should I pay attention to when using robot lithium battery?

Ni-MH battery packs Vendor

Nickel Hydride No. 5 battery