|Posted on November 4, 2015 at 6:00 PM|
Current rechargeable batteries are almost exclusively lithium ion-based. Since its invention in 1912 and first commercial product in 1970, the lithium ion battery has been an important part of modern mobile technologies. While it has a number of advantages, such as high energy density, low memory effect and reasonable recharging cycle time, it also has drawbacks in terms of cost and safety. With increasing demand for rechargeable batteries for portable electronics, electric vehicles and energy storage applications, there is clearly a drive to find alternative rechargeable batter materials.
Dr. Rana Mohtadi, a Principal Scientist at Toyota, and her colleagues recently demonstrated a promising result towards developing a magnesium (Mg) battery. Magnesium is a good candidate as a battery material because of its high storage capacity (twice that of lithium), abundance, and benign properties. One of the challenges in developing Mg battery has been finding electrolytes that could work with a Mg anode, conduct Mg ions, and operate in a stable manner. A recent issue has involved the tendency of Mg to corrode metallic components in the battery, such as steel castings and current collectors. Mohtadi and her colleagues found a solution to this problem in an electrolyte based on the
salt magnesium monocarborane, Mg(CB11H12)2, which is soluble in traditional solvents that conduct Mg ions and is not prone to oxidization.
With this new electrolyte, and platinum and stainless steel electrodes, Mohtadi's cyclic voltammetry tests found that the electrolytes remained stable without corroding the metallic components. A Mg battery coin cell made of their new electrolyte could charge to 3.5 V, compared to
2.5 V for a conventional halide-based electrolyte battery. Just like the Li battery, which took more than half a century to become commercially available, a Mg-based battery still has a long way to go. But Mohtadi and her colleagues' work is an important step towards making this cell commercially viable. Detail of this work were published in Angewandte Chemie, on May 26th, 2015.
Dr.Mohtadi has been working at Toyota for over 10 years, and has led many projects in developing novel battery chemistries. She was recognized in the "40 under 40" list by Automotive News and Crain's News in 2014, and received an R&D 100 Award in 2011.
- Written by Eugene Choi, Edited by Paulette Clancy