Time:2024.12.25Browse:0
The mesoporous matrix is composed of r-GO layers, which provide a place for electrochemical reactions and provide a highly conductive path for electrons. The highly porous structure is easily permeable by the channel solution, allowing the sulfur active species to be evenly distributed in the conductive graphene matrix and ensuring efficient electrochemical reactions. This is driven by the high capacity of 3.4 mAh cm-2 - at a high mass load - 3.2 mg cm-2 of cathode sulfur - and the total sulfur load in the Li-S cell is even double that (6.4 mg cm-2).
Graphene oxide aerogel helps lithium-sulfur batteries achieve new energy density
Graphene aerogels have high porosity properties that allow them to fully absorb sulfur, making the catholyte concept worthwhile.
Furthermore, the presence of oxygen groups in the r-GO aerogel structure stabilized the cycling performance, while Li-S cells using fluorine-free catholyte achieved a capacity retention of 85% after 350 cycles. A paper about their work was published in the Journal of Power Sources. A traditional lithium-ion battery consists of four parts: two supporting electrodes whose surfaces are coated with an active material; an electrolyte; and a separator that acts as a physical barrier that prevents contact between the two electrodes while allowing ion transfer.
Researchers have previously tried combining the cathode and electrolyte into a liquid - an electrolyte. This concept can help batteries reduce weight and provide faster charging and better power delivery capabilities. Now, with the development of graphene aerogels, this concept has been shown to be feasible and provides promising results.
Taking a standard coin battery case, the researchers first inserted a thin layer of porous graphene aerogel. Then, a sulfur-rich solution - the electrolyte - is added to the battery. The highly porous aerogel acts as a support, absorbing the solution like a sponge.
The porous structure of graphene aerogels is key. It absorbs a lot of Epsom salt, giving you a high enough sulfur load to make the concept of Epsom salt worthwhile. This semi-liquid laxative is essential here. It allows the sulfur to cycle back and forth without any loss. It is not lost by dissolution because it is already dissolved in the catholyte solution.
In order for the electrolyte to play its role as an electrolyte, part of the electrolyte solution is also added to the separator. This also maximizes the sulfur content of the battery.
The new design avoids two major problems with lithium-sulfur battery degradation: the dissolution and loss of sulfur into the electrolyte, and the shuttle effect in which sulfur molecules migrate from the cathode to the anode. In this design, these undesirable problems can be significantly reduced. However, the researchers note that the technology still has a long way to go before it reaches its full market potential. Because these batteries are produced in a different way than most ordinary batteries, new manufacturing processes will need to be developed to make them commercially viable.
Read recommendations:
LR14
Some performance requirements of high magnification batteries.902030 polymer battery
Power type lithium battery and ordinary lithium battery difference
Nickel Metal Hydride No. 15 battery wholesaler
Column rechargeable battery