Batteries have become essential components to human life. Since the development of the first lithium ion batteries (LIBs) in the 1970s and Sony commercialising the first rechargeable product in 1991, the world has become accustomed to the convenience of portable power - for the ever increasing range of devices such as mobile phones that are in daily use.
LIBs also play a serious role in global efforts to clean up the environment. As the world endeavors to replace fossil fuels with clean energy, take-up of electric cars for example, which are powered by LIBs, is set to increase.
Mining lithium, however, is fraught with challenges and not without environmental consequences, as the toxic leak from the Ganzizhou Rongda Lithium mine in 2016 amply demonstrated - dead fish found floating in the Liqi river was clear evidence of a disrupted local ecosystem.
There is, therefore, a real need for battery research and development. New technology needs to be developed that uses more common, more environmentally friendly and less toxic materials to make batteries. But a balance needs to be struck: it will be futile if new batteries are less dense or use more expensive materials as their overall impact on the environment could be negative.
Battery Research using NMR, EPR and MRI
Central to achieving these goals, and developing next-generation technology that can overcome current energy limits of LIBs, is the need for a deeper understanding of the underlying chemistry of the materials at a researcher's disposal, and important aspects of the key reactions happening in LIBs.
Bruker's long experience and range of technologies, including nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR) and magnetic resonance imaging (MRI), are helping researchers to achieve these goals.
Although techniques such as electron and optical microscopy offer high resolution imaging, they are often limited to surface imaging and are difficult to interpret quantitatively. NMR and EPR spectroscopies are both non-invasive methods with quantitative capabilities, and research is continuing to improve sensitivity and increase resolution. In addition, associated powerful imaging techniques such as MRI are being used in a new multi-technique analytical paradigm.
Towards the Batteries of the Future
A range of strategies are in development and under review to push the performance limits of current LIBs. In parallel, research into more radical alternatives is also accelerating. All-solid-state batteries are a good example of these new approaches.
Solid-state batteries would represent a major shift in battery technology. This concept is far from new, but during the past 10 years new families of solid electrolytes have been discovered, which could offer a marked improvement in safety, as they are non-flammable when heated, unlike their liquid counterparts. In addition, solid state batteries permit the use of innovative, high-voltage, high-capacity materials that may help overcome performance issues. The resulting battery would potentially offer significantly increased energy density and improved battery life.
As research scientists work to balance our future portable energy needs with reducing environmental impact, they will rely more and more on analysis using NMR, EPR and MRI.