Brief description of the material for doubling storage of lithium batteries

For many years, mass-produced lithium-ion batteries have relied on graphite and copper as their anodes. For years, researchers have been looking for alternative materials that can overcome the limitations of these materials, including high-cost production and limited storage capacity (for example, Silicon can store 10 times the energy, although it poses another series of problems).

Creating the current anode is a laborious multi-step process in which graphite is coated with copper foil. However, as Karl Kreder, a material scientist at the University of Texas at Austin and lead author of the new research, explains, in terms of manufacturing processes and the battery itself, this can lead to inefficiency.

Kreder said: "So the active material(graphite) is painted on the top of the inert collector(copper). This increases the volume of the system and the quality of inactive materials. By combining the collector and active materials, higher capacity active materials can be used while using less inactive current collection materials. "

Kreder and his team achieved this through a simplified manufacturing method that eliminated the cumbersome coating process. When tin is cast into a block, tin can be directly added to the aluminum to form an alloy which can then be mechanically rolled (relatively inexpensive and common metallurgical alloying processes) into nanostructured metal foil. In the final step, the particles in the material are reduced, which is crucial.

Kreder explained: "tin can be alloyed with lithium. Unfortunately, if tin foil is used or even micron-sized tin particles are used, tin will break when it is alloyed with lithium due to volume expansion, which means that if it is large the tin pellets make batteries that can only sustain dozens of charge and discharge cycles, but if nanoscale tin particles are produced, the particles will not split during alloying."

The researchers called the material known as the cross-eutectic alloy (IdEA) anode. They think that the thickness of the material is only one quarter of the thickness of the traditional anode material and the weight is only half that of the traditional material. They tested the anode material in small lithium-ion batteries and then charged and discharged it to measure performance. They found that the anode had twice the capacity to store electricity as a conventional copper-graphite anode.

Kreder said: "The reason for this is very good, one of the elements is active, tin, the other is inert, aluminum. "Aluminum produces a conductive matrix in which the tin remains, and aluminum provides Structure and conductivity, while tin alloys and de-alloys with lithium during battery cycling.

"It's really exciting to be able to develop a cheap, scalable process for making electrode nanomaterials," said Araugam Manthiram, director of the Texas Institute of Materials, one of the team's leaders. Our results show that this material has been successful in terms of the performance metrics required for the commercialization of lithium-ion batteries. "

The results of the study were published in the journal ACSENEY LETTERS.

The page contains the contents of the machine translation.