At present, the widely used lithium-ion battery can achieve an energy density of 265 WH / kg and a capacity of 185 MAH / g, while the lithium sulfur battery theoretically has an energy density of 2600 WH / kg and a capacity of 1675 MAH / g. In other words, the performance of lithium sulfur battery is 10 times better than the current lithium-ion battery, and the application prospect is very promising. However, the sulfur conversion reaction is slow in the process of charge and discharge, resulting in low utilization rate and serious dissolution of sulfur, The research team led by Professor Liu Jian and Professor Wu Zhongshuai from Dalian Institute of Chemical Physics (DICP), Chinese Academy of Sciences, seems to have found a solution recently: carbon nanosphere lithium sulfur battery cathode.
The study was published on the international top journal advanced energy materials in the field of energy materials on April 16. The working mode of these nanospheres is similar to that of battery cathode nano reactor. The key problem of lithium polysulfide (lips) dissolution in lithium sulfur battery can be solved through Fe1 XS electrocatalyst decoration. It should be known that when lithium polysulfide is dissolved, the battery will lose sulfur and charge discharge cycle stability.
These nanospheres have high porosity and can adsorb up to 75% of the high sulfur load, so as to avoid the dissolution of lithium polysulfide. According to the researchers, the capacity of nanospheres remained stable after 200 charge discharge cycles at a current density of 0.5 C, with little attenuation from the initial value of 1070mah / g. It is worth mentioning that electric vehicles may face greater current density, which can reach 4C during fast charging. If scientists can prove that these carbon nanospheres can resist such high current density, the lithium sulfur battery made from them may be 10 times higher than the range provided by the current electric vehicle battery, or half the size of the compromise battery, but get 5 times the range.
In addition, lithium sulfur battery has a cost advantage that can not be underestimated. The materials used in lithium sulfur batteries are much cheaper than lithium-ion batteries, and sulfur is very rich in nature. Therefore, the price is much lower than that of lithium-ion batteries. It is expected to realize the cost of $100 / kWh of the lifeline of the popularization of electric vehicles.
In fact, LFP lithium iron phosphate battery has made gratifying development recently, but it is still a certain distance from the above cost line. With the continuous development of battery technology, electric vehicles have a bright future, but it takes a long time to finally arrive.