In-operando XRD helps KETI build better batteries

The Korea Electronics Technology Institute (KETI) is a leading government body engaged in the research and development of new electronics and sustainable energy solutions for Korean companies such as Samsung SDI. Realizing the importance of next generation Li-ion batteries in portable electronics, electric cars and energy storage, KETI started an “Advanced battery research centre (ABRC)” dedicated to the battery research with pilot scale cell production facility, within its Smart Energy Manufacturing R&D division. Goal of this project is to provide more powerful and lighter battery cells for mobile phones, laptops, electric cars and a range of other portable and energy storage devices. 

In the frontiers of battery research

ABRC has its focus on enhancing the energy and power density, improving the safety and reducing the cost of new generation batteries. Its research areas include new generation of electrode materials for current Li- ion batteries, solid state electrolyte for all solid-state batteries, Lithium sulphur batteries, Redox flow batteries, supercapacitors and the efficient technologies for battery recycling. To support this cutting-edge research, KETI needed an in-house, state of the art, cell testing facility. The X-ray diffractometer was procured as part of the must have analytical instrumentation for this facility, as in operando X-ray diffrcation (XRD) provides a rare insight into the crystal structure changes as Li-ions shuttle between anode and cathode during charge/discharge cycling.
 
“While selecting the right XRD instrument for our research needs, the key criteria were the highest sensitivity to crystal phase changes, full integration of electrochemical cell with XRD, ease of use, and the local application support – and the Empyrean X-ray diffractometer proposal from Malvern Panalytical Korea fulfilled all our requirements – making our selection process straight forward. Moreover, the instrument was the first of its kind to be delivered in Korea dedicated to the battery research.”

Dr. Cho Woo Suk (left) and Dr. Kim Jeon Soo from KETI leading the research into the secondary battery

In operando XRD: A must have technique for battery research

While developing new battery materials with varying chemistry, it is important to understand the stability of these materials when cycled in a battery cell. Many materials look promising in terms of high energy density and discharge capacity, but undergo a rapid capacity decrease upon cycling. Most times the capacity decay can be traced back to the structural stability of these materials during charge-discharge cycles. Key focus of our research is to enhance the structural stability of cathode materials to improve the discharge profile over the lifetime of the battery. Changes in chemistry of cathode materials induce critical changes in the crystalline structure of the electrode materials and these need to be closely monitored. XRD is used as the first-choice analytical technique to monitor important parameters like: 

• Formation of multiple phases 
• Changes in the crystallite size of electrode materials with chemistry 
• Abrupt lattice expansions and contractions and phase transitions leading to particle cracking 
• Changes in crystallite size during cycling 
• Surface modification/plating

The Empyrean platform, equipped with an in operando electrochemical cell, helps us in understanding the battery degradation mechanisms, and develop rechargeable batteries with improved lifetime, superior charge/discharge cycling and low discharge losses.