Manufacturers still use lithium-ion batteries almost exclusively in smartphones and other gadgets, because this technology is already proven, easy to manufacture and relatively cheap. However, it also has flaws: batteries typically lose 50-80 percent of their capacity during 4-500 charging cycles, and the starting capacity can’t be called the best either. To cite just two examples: phone manufacturers are unable to launch a mobile phone that can last reliably for at least two days, and in the case of electric cars, manufacturers play with the range and the weight of the battery to find a good ratio.
It is no coincidence that the aim of countless researches is to develop a better alternative to the lithium-ion battery. Now, researchers at Monash University in Melbourne have come up with a new idea: they replaced the metal oxide electrode that acts as a cathode with a sulfur-based one.
With the change, the theoretical capacity of the battery is eight times compared to the lithium-ion core solution, and in practice it is roughly five times – the difference is that the sulfur electrode expands and contracts more during charging and discharging, so it needs more space than a metal oxide in the case of an electrode. In other words, with the same size, “only” five times the capacity can be achieved, which is, of course, still remarkable. After all, this means that a smartphone can last for five days on a single charge, and the range of electric cars can reach over 1,000 kilometers, while the weight of the battery is reduced by hundreds of kilos.
Researchers have experimented with sulfur before, but they failed to achieve a breakthrough because they limited the expansion of sulfur with additives, which led to premature decomposition and thus a rapid decrease in capacity. In contrast, with the current method, the durability of the battery is also excellent: after 200 charging cycles, 99 percent of the initial capacity is still available. Another advantage of sulfur is that it is also much cheaper, as it is available in much larger quantities than the rare earth metals used in lithium-ion batteries.
The problem is that we always have to write at the end of the news about new battery technologies that it is only an experimental solution for the time being; and it is no different now. Unfortunately, it is not possible to know when the technology can be commercialized, the researchers only said that they are investigating the possibility of how the solution could be sent into production in the coming years.
Source: geeks.hu
