It is beyond any doubt that lithium-ion batteries have significantly impacted the world with their high energy density and ability to be recharged. Unfortunately they are also fairly near their current limits, without the development of new technology. Many researchers and institutions are working such technologies and those at Rice University have recently created a battery with three times the capacity of what we see today.
What makes this new battery special is that its anode is not made of graphite, but a hybrid of graphene and carbon nanotubes. This hybrid is actually a metal and can hold more lithium ions than modern batteries, but most importantly it overcomes an issue common with other lithium-metal batteries. Dendrites are lithium structures that can grow inside of a battery, crossing the electrolyte possible connecting the two electrodes, causing a short circuit. Such a short circuit could cause the battery to fail, catch on fire, or explode. The hybrid materials has a high surface area and a low density, which is a valuable combination as it means the lithium particles are free to move in and out as the battery charges and discharges. This also allows the lithium to evenly distribute itself, which suppresses dendrite growth.
The prototype batteries the researchers have built have their capacity limited by the cathode, but this anode material is still able to hold near the theoretical limit of 10 times more energy than traditional lithium-ion batteries. When tested, the full batteries also were able to retain 80% of their capacity after some 500 charge-discharge cycles and were free of dendrites when examined with an electron microscope.
Source: Rice University
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