Batteries are not what they could be yet, and a lot of research goes into perfecting them. A team of researchers at the University of Waterloo, Canada have been focusing on perfecting the lithium-ion battery, mainly by looking at the negative anode of these batteries, which are typically made from graphite.
According to the team, graphite has been used to create the negative electrodes in lithium-ion batteries, for a long time, but with the overall improvements in batteries, this material is becoming obsolete in terms of the limited amount of energy that it can store. The team has found a way to effectively replace this material with silicon.
When graphite is used, the maximum theoretical capacity of the battery is 370 mAh/g (milliamp hours per gram), while by using silicon the theoretical capacity jumps to 4,200 mAh/g. Silicon is also a much cheaper material. However, before it can be used, a way to prevent the silicon cracking had to be found. This cracking occurs when it interacts with the lithium inside the cell during the charge cycle, which causes the silicone to expand and contracts by more than 300 percent, and it is the cause of battery failure.
To combat this shortcoming, the team has developed a flash heat treatment for the silicon electrodes, which gives them a more robust nanostructure. Because of this structure, the contact between the lithium and the electrode has been lessened, which eliminates most of the expansion and contraction.
The new battery they designed has a capacity of than 1,000 mAh/g (or over 2,275 cycles), while the team is also sure that it will have a 40 to 60 percent increase in energy density over normal lithium-ion batteries. If these batteries would be used in an electric car, for example, it could go 300 miles on a single charge, while it would also be lighter, since the new batteries are lighter. The team is hopeful that the new batteries will be available commercially as early as next year.
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