3DOM Inc. (Yokohama City, CEO: Masataka Matsumura), an entrepreneurial venture company originated from Tokyo Metropolitan University, has successfully developed a lithium ion battery that has enhanced both energy density and reliability.
Application of lithium ion battery is expanding all around the world, particularly to electric vehicles (EVs), small consumer applications such as smart phones and drones, and stationary energy storage systems that are installed in houses with solar panels.
Lithium ion battery, however, uses many combustibles as materials for electrolytes and other components. The lithium-nickel-cobalt composite oxide used as the cathode material can be locally short-circuited depending on the usage such as repeated rapid charging and discharging. When Joule heat is generated because of such reasons, there is a possibility that the cathode material is thermally decomposed, thereby releasing oxygen, and at the same time, the electrolytic solution is burned to cause ignition. If another cathode material such as a lithium composite oxide having higher heat resistance is used, there is an issue of reduced energy density. Under the situation that batteries with higher energy density are required, how to improve reliability without lowering energy density has been a challenge.
This time, 3DOM has paved a way to maintain and improve the energy density of the battery through the application of 3DOM’s unique material mixing technology while improving the reliability of the battery by application of highly heat resistant material as a portion of cathode materials. Further, this particular heat resistant material is composed without the use of rare earth cobalt. As it has become possible to reduce the portion of cobalt in the entire cathode materials of the battery, this technology will lead to avoid future fluctuation in market prices of cobalt and to counteract its resource shortage.
The new lithium ion battery cell that is successfully developed this time is housed in a pouch and is in a 30 Ah class. 3DOM has started supplying samples to several companies mainly in Southeast Asia by utilizing 3DOM’s own network and Singapore subsidiary. Further, 3DOM is studying the application of the battery cells to the products of LAVLE, which is 3DOM’s US affiliate that engages in the electric vessels business. Currently, in cooperation with battery manufacturers in the alliance, 3DOM plans to use some portions of the existing factories for mass production and sales of the battery cells from 2021.
In the future, 3DOM aspires to further improve energy density while improving reliability of batteries by using higher energy density materials and applying 3DOM’s proprietary separator technology that realized a uniform three-dimensional multi-porous structure.