Lithium-ion batteries are at the heart of devices that include smartphones, laptops and ever-growing electric cars, etc. So many researchers are interested in using advanced materials to improve lithium-ion battery performance, making them lighter and more compact, Can store more energy.A new tin-aluminum alloy developed by Texas engineers may work in three areas, even at the same time may make its production faster and lower production costs.
Over the years, mass-produced lithium-ion batteries have relied on graphite and copper for their anodes. Over the 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 constitutes another series of problems).
Creating today's anodes is a laborious, multi-step process in which graphite is coated with copper foil However, as explained by Karl Kreder, a material scientist at the University of Texas at Austin and a leading researcher in the new study, the manufacturing process and the battery itself In terms of doing so, this can lead to inefficiencies.
Kreder said: 'So the active material (graphite) is coated on the top of an inert current collector (copper), which increases the volume of the system and the quality of the non-active material, by combining the current collector with the active material, a higher capacity Active materials, using fewer inactive current collection materials.
This is achieved by Kreder and his team through a simplified manufacturing process that eliminates the cumbersome coating process.When tin is cast into pieces, tin can be added directly to the aluminum to form an alloy that can then be mechanically Rolling (relatively cheap and normal metallurgical alloying processes) is a nanostructured metal foil. In the final step, it is crucial that the particles in the material be reduced.
Kreder explains: "Tin can form an alloy with lithium.Unfortunately, if tin is used or even micrometer-sized tin particles, tin breaks when cycled due to volume expansion when forming alloys with lithium, which means that if large Of the tin particles make the battery, only to maintain dozens of charge and discharge cycles, but if the manufacture of nano-scale tin particles, the particles will not be split during alloying.
The researchers called the resulting material a cross-eutectic alloy (IdEA) anode, which they considered to be only a quarter of the thickness of conventional anode materials and only about half the weight of traditional materials. They were fabricated in small lithium-ion batteries The anode material was tested and then charged and discharged to measure the performance, and they found that the anode had twice the power storage capacity of a traditional copper-graphite anode.
Clyde said: 'This is done for a good reason, one of the elements is active, tin, and the other is inert, aluminum.' Aluminum makes a conductive matrix in which the tin is retained and aluminum provides Structure and electrical conductivity, while tin is alloying and de-alloying with lithium when the battery is cycled.
Arumugam Manthiram, director of the Texas Institute of Materials, one of the team's leaders, said: 'It is very exciting to be able to develop a cheap, scalable electrode nanomaterial manufacturing process. Our results show that This material has been successful in the performance required for the commercialization of lithium-ion batteries. '
The research is published in ACS Energy Letters.
