Multi-electron transfer reaction based high energy and low cost batteries.
ORLIB's approach to high-energy density began with the study of electrode active materials responsible for charge / discharge reactions.
As a result, we have developed a technology that allows (1) 4-electron reaction Si and (2) 3-electron reaction organic thioamine compounds to be used as electrode active materials for rechargeable batteries, and open up the possibility of high-energy batteries using these.
Silicon, Si, has been attracting attention as a high-capacity anode material since the atom can react with 4 or more electrons, leading the significantly large capacity up to 4000 Ah/kg. However, Si has hardly been used because it has a large irreversible capacitance, a large volume change due to a charge/discharge reaction, and the capacity is too large compared to the cathode active materials, resulting in poor anode and cathode balance. ORLIB has developed the pressurized pre-doping technology as a technology to mitigate the irreversible capacitance and the volume change during a charge/discharge reaction.
Sulfur (S, molecular weight 32) can receive electrons and react with two Li atoms, reaching an extremely high capacity of over 1200 Ah/kg. However, after the second cycle, the capacity decreases and becomes almost zero in several tens of cycles. It is considered that the Li-sulfur formed in the discharge process was dissolved into the electrolytic solution and desorbed from the electrode.
To solve this problem, various methods have been considered around the world, such as attaching S to the side chain of the polymer to prevent it from leaching, confining it in a micro cage, or solidifying the electrolyte to prevent it from leaching out.
ORLIB has succeeded in achieving both high capacity and excellent cycle life by using an organic thioamine that undergoes a multi-electron reaction as an oligomer. Their theoretical capacity of 700 Ah/kg, which is nearly 4 times higher than that of Li-ion battery.
Y. Wang, M. Satoh, M. Arao, M. Matsumoto, H. Imai, and H. Nishihara, "High-energy, Long-cycle-life Secondary Battery with Electrochemically Pre-doped Silicon Anode", Scientific Reports, 10, 3208 (2020). https://doi.org/10.1038/s41598-020-59913-4 (Open access)
ORLIB battery has been developed based on the Li-ion battery technology. Therefore, we have various facilities that can be used not only for the development of new batteries but also for the development of general Li-ion batteries.