The day we dreamed our smartphones and laptops will become less dependent outlets may be closer than we think: Stanford University researchers managed to design a type of lithium battery that lasts two to four times longer than current batteries.
The research is being conducted by Professor Yi Cui, the same as in February this year announced a team of technical manufacturing batteries inspired by pomegranates .
Batteries are formed essentially of three components: electrolyte, anode and cathode.The electrolyte acts as a conductive substance between these last two, allowing electrons to be discharged one and received by another.
Scientists believe that the ideal would be to get there in pure lithium anode. Besides resulting in much more autonomy, this condition would allow the development of smaller, lighter batteries.
But in current technology, there is only concentrated lithium ions in the electrolyte. This is because the industry still could not create a pure lithium anode that was not highly unstable and unable to react to the electrolyte, problems that cause a reduction in the useful life of the battery and, under certain circumstances, increase the risk of accidents.
The solution found by Professor Yi Cui team has connection with the idea of batteries inspired by pomegranates: use layers of “nanospheres” carbon with empty cores and interconnect them as forming the cells of a honeycomb to protect molecules lithium.
Typically, the industry uses graphite and, less frequently, the silicon anode. All these elements can be expanded, but not as much as lithium. From this came the instability of the material.
The carbon spheres can control this problem because they are durable enough to prevent the lithium from expanding excessively and, at the same time, having flexibility that allows it to move along the molecules element.
The carbon layers are extremely thin, having no more than 20 nanometers thick, so it does not affect the physical dimensions of the battery significantly. To give you an idea, the researchers explained that it is necessary to stack layers 5000 so that they gain, gaskets, the thickness of a hair.
As the lithium can offer higher energy density, one can do more with less, or that produce smaller current batteries, but battery life of two to four times as reported in the early post. There is one more benefit: since the carbon layers are lithium remain stable, it is easier to develop batteries with longer lifetime.
With so many advantages, which lack the idea to be implemented on smartphones, laptops and even cars? More tests, of course. One of the challenges for scientists is to make the new batteries have “coulombic efficiency” (the difference between the amount of charge the battery during discharge and lose the gains that during recharging) of 99.9% to be viable. The most that has been achieved in the laboratory is an efficiency of 96%. It may seem a small difference, but it is not.
Anyway, as the new technique is based on current technologies (ie, it is not anything made from “scratch”), the researchers believe the adoption within a few years.
We just hope that by then, the levels of consumption of our devices do not increase in the same proportion.