I can’t attest to the headline “Almost a Perfect Battery†claimed by a team of researchers at MIT, but they reported that they have developed a solid-state electrolyte, which can greatly boost modern battery technology. The researchers claim that the new design will allow batteries to endure hundreds of thousands of recharges, pack more juice and be safe from combustion. The research was published in Nature Materials (published August 17, 2015).
Now researchers at MIT’s Advanced Institute of Technology in Cambridge, Massachusetts and Korean consumer electronic producer Samsung have collaborated in developing a new approach to one of the three basic components of batteries: the electrolyte, which transports charged ions from one electrode to another during charging and discharging. Modern lithium-ion batteries use liquid electrolyte, but the MIT group have developed a better all-round solid-state electrolyte. Their invention belongs to a class of materials known as superionic lithium-ion conductors, which are compounds of lithium, germanium, phosphorus and sulfur.
The new solid electrolyte can withstand hundreds of thousands of recharge cycles, meaning a battery made with it would last practically forever. It has superior energy density, packing 20 to 30 percent more energy for a given volume. It is also more stable than a liquid electrolyte, meaning the rare (but widely publicized) cases of battery combustion would no longer be possible. This solid-state electrolyte also has other, unexpected benefits: while conventional lithium-ion batteries do not perform well in extreme cold, and need to be preheated at temperatures below roughly minus 30 degrees Celsius, the solid-electrolyte versions can still function at those frigid temperatures.
The paper in Nature Materials describes a new approach to the development of solid-state electrolytes that simultaneously addresses the greatest challenges associated with improving lithium-ion batteries. The key to making this feasible was finding solid materials that could conduct ions fast enough to be useful in a battery. Apparently, there was a view that solids cannot conduct fast enough, however the research team has dispelled that paradigm. The research team was able to analyze the factors that make for efficient ion conduction in solids, and hone in on compounds that showed the right characteristics.
The team says the principles derived from their research could lead to even more effective materials. So again we see that Rare Metals – the likes of lithium and germanium – Matter.
Until soon… Ian
Source: http://raremetalsmatter.com/almost-a-perfect-battery/