It is necessary to store energy generated during low demand periods and use it during periods of high demand. Excess energy generated during this low demand period can be used to charge an energy storage device. Energy grids cannot cope with a surge in demand for electricity and increasingly volatile supply from renewable power sources. Among other storage methods and technologies, chemical energy storage devices (batteries, fuel cells, supercapacitors etc.) remain the leading electrical energy storage technologies today. However, current electrochemical storage technology cannot meet the required demand for transportation, commercial residential applications, and large scale stationary renewable energy storage applications. Fundamental basic science research is necessary to understand the underlying principles in each related process in the electrochemical storage systems in order to address future energy storage requirements.
Lithium ion batteries currently dominate in portable electronic industry, the electric vehicle market, and the utility market for grid-energy storage. The goal for electrochemical storage technology in the transport sector is to develop the technologies to reduce battery costs from their current $500-600/kWh to below $125/kWh. Current battery technology is far from its theoretical energy density limit. In the near-term, with rapid advances in lithium-ion technology, it’s envisioned to improve the battery pack energy density from 100 Wh/kg to 250 Wh/kg through the use of novel high-capacity electrodes and higher voltage electrolytes. In the longer term, “beyond Li-ion” battery chemistries, such as lithium-sulfur, magnesium-ion, zinc-air, and lithium-air, offer the possibility of energy densities that are significantly greater than current lithium-ion batteries as well as the potential for greatly reducing battery cost. Aqueous Na-ion batteries provide an economical avenue for rechargeable batteries despite its low energy density. For stationary energy storage applications flow batteries and Na-S batteries may offer promise for high energy density storage at reduced cost.
The Conn Center strives to be at the forefront of the next generation energy storage devices. The Energy Storage lab is dedicated to discovering and manufacturing tomorrow’s energy storage capabilities.
The Conn Center has been actively involved in the development of new materials and innovative chemistries for Li-ion batteries, Na-ion batteries, Li-S batteries, Mg-S batteries, fuel cells, and flow batteries etc. The facility is focused primarily on development of high energy density and high power density batteries in large scale at low cost. Energy storage requirements demand the development of long-lasting rechargeable batteries with nano-materials based electrodes, novel electrolytes (ionic, polymeric, gel, solid state) and advanced membranes, rapid screening of materials for batteries, and modeling of battery performance at the molecular level.
Near Term Objectives
Low cost, high energy density lithium ion battery technology through high energy density anode and reduced cost of manufacturing.
Demonstrate new battery chemistry concepts for lithium metal free Li-S battery technology.
Demonstrate pre-lithiated anode technology.
Establish facilities for flow battery research and choose a redox couple.
Mid Term Objectives
Demonstration of Li-S pouch cells (200 mAh) to achieve > 450 Wh/kg over 100 cycles at C/3 rate
Develop solid state electrolytes for Li-ion and Li-S batteries with lithium ion conductivities necessary for scalable storage.
Demonstrate feasibility of a flow battery concept
Long Term Objectives
Translate low cost and durable high energy density storage systems for transport and stationary applications.
Develop flow battery technology at scale necessary for solar farms (10 – 100 MWs).
Gamini Sumanasekera, PhD
Professor of Physics & Astronomy
Theme Leader Energy Storage
Conn Center for Renewable Energy Research
University of Louisville
Ernst Hall Room 302, 216 Eastern Parkway
Louisville, KY 40292
Email Dr. Sumanasekera