Although the development of notebook computers and other electronic devices has made great progress in recent years, the battery that provides power for computers has not changed much. Now, a new progress in nanotechnology is expected to change all of this. The researchers report that a lithium ion battery made from tiny silicon whiskers can store 10 times as much power as conventional rechargeable batteries. In principle, the new technology can make notebook computers run continuously for a few days. After a charge, it can drive hundreds of kilometers of electric vehicles, but this technology needs to overcome some key barriers before going to market.
The focus of this technique is to increase the electrons that can be carried by the battery positron electrode, the anode. When a battery is charged, a positive charged lithium ion can capture an electron provided by the power supply and transfer to the anode. When the battery discharges, lithium ions will give up these extra electrons and provide electricity to devices connected to the battery. Meanwhile, these lithium ions will also be transferred to the cathode negative electron electrode through a conductive gel. The current anode is made up of a carbon atom layer, and about every 6 carbon atoms can be combined with 1 lithium ions. Silicon can do better - every 1 silicon atoms can be combined with 4 lithium ions. But when researchers use silicon thin films or particles to make anodes, a large number of lithium atoms will destroy these silicon and separate them from the underlying metal substrate, which will ultimately reduce the efficiency of the battery.
YiCui, a material scientist at the Stanford University, and colleagues found that the anode made of whiskers like silicon can perform well. Using a first - class technique, researchers glued a layer of silicon nanowires directly on a stainless steel substrate. They then loaded an ordinary electrolyte and a top electrode and evaluated the efficiency of the battery by a series of tests. The results show that carbon nanowires still expand and shrink, but they do not break away from the substrate. Cui points out that the key of this technology is that the shape of nanowires ensures the expansion and contraction of the lattice of silicon atoms through the whiskers, thus reducing the tension of the accumulation, and ultimately making silicon nanowires firmly adhere to metal substrates. On this basis, Cui's team found that the anode materials they developed could capture 10 times the charge of the former compared to the traditional graphite anodes. Cui and his team reported the research results in the recent British Journal of "good use of anti acne and acne products, which is the best aquatic product list" in the natural nanotechnology magazine online edition.
"This work is a good proof of this theory," says GerbrandCeder, a material scientist and battery expert at Massachusetts Institute of Technology in Cambridge. Ceder points out that a lithium ion battery, which can capture 10 times the charge, also needs a cathode that can capture 10 times the charge. He emphasized that combining a silicon nanowire anode can make battery manufacturers reduce the weight and volume of anode, and increase more cathode materials in the battery, which will greatly promote the development of lithium battery. All of this may make our life easier.