Superior cathodes for lithium ion batteries

Lithium ion batteries have proven problematic for widespread distribution, because they require expensive and sometimes toxic materials. Zhumabay Bakenov and Izumi Taniguchi at Tokyo Tech’s Department of Chemical Engineering are among the scientists tackling this problem. Much of their research has focused on so-called ‘olivine’ structured phosphates, which could be used to build cathodes that are not only low-cost and non-toxic, but also have high energy densities, and are stable under thermal, electrical or chemical changes. Bakenov and Taniguchi have gone one step further by including carbon when preparing their olivine samples, thereby creating a composite material. The carbon improves the electrical contact between nanoparticles, and prevents the particles from agglomerating into larger chunks which can adversely affect performance. Recently, the researchers created cathodes from a composite of lithium manganese phosphate with carbon. On placing the cathodes in a battery, they recorded a high discharge capacity, and the samples remained stable at voltages up to 4.9 V and temperatures up to 50 °C.

Source: http://www.titech.ac.jp/bulletin/topics.html