(6dn) Fit Batteries to the Grid or Grid to the Batteries?

The CapEx of batteries accounts for 60% of the entire microgrid components, which is the most significant portion as a single component,¹ but current approaches to integrating batteries into the entire microgrid components do not make batteries economically feasible. Typically, batteries are treated as a black box that does not account for their internal states in current microgrid simulations.^2-5 This might lead to under-utilization and over-stacking of batteries. In contrast, detailed physics-based battery models, accounting for internal states, can save a significant amount of energy and cost, utilizing batteries with maximized life and usability.^6,7 It is important to identify how efficient physics-based models of batteries can be included and addressed in grid control strategies.⁸

In this talk, simple examples for Battery-PV microgrids and the direct simulation of the same including physics-based battery models will be presented.⁶ It is straightforward to implement other batteries in this efficient equation-based microgrid framework. For example, one might visualize a situation in which lithium-ion batteries with different chemistries being used simultaneously, sometimes even flow batteries in combination with lithium-ion batteries. The model of the battery as a pack can be considered as well (e.g., a set of cells in series and parallel with slight inherent variation in SOC and SOH). The results of the proposed approach are compared with the conventional approaches and improvements in performance and speed are reported.

References

1. N. Ivanova, Energy storage update, London, UK, 2015. Available: http://analysis. energystorageupdate.com/lithium-ion-costs-fall-50-within-five-years
2. D. A. Beck, J. M. Carothers, V. Subramanian, and J. Pfaendtner, AIChE Journal, 62 (5), 1402-1416 (2016).
3. X. Li, IET Renewable Power Generation, 6 (5), 340-347 (2012).
4. X. Li, D. Hui, and X. Lai, IEEE Transactions on Sustainable Energy, 4 (2), 464-473 (2013)
5. P. Naderi, Journal of Solar Energy Engineering, 135 (2), 024506 (2013).
6. S. B. Lee, C. Pathak, V. Ramadesigan, W. Gao, and V. R. Subramanian, Journal of The Electrochemical Society,164 (11), E3026-E3034 (2017).
7. M. Pathak, D. Sonawane, S. Santhanagopalan, R. D. Braatz, and V. R. Subramanian, ECS Transactions, 75 (23), 51-75 (2017).
8. V. R. Subramanian, (A. Staller, ed.), ECS redcat blog, The Electrochemical Society, USA, 2017. Available: https://www.electrochem.org/redcat-blog/free-batteries-towards-bottom-r…

Research Interests:

My research interests are centered around battery simulation, model-based experimental validation, and battery and renewable application integration (e.g., renewable grids and electric vehicles). These challenging problems are multi-disciplinary and require collaboration with scholars in other engineering or industrial fields. These types of collaborations tend to be strongly encouraged by funding agencies. My research background in the renewable energy field of modeling (Ph.D.) combined with my previous experimental experience (M.S.) will help to facilitate active collaboration. If I can continue my research as an assistant professor, I plan to submit several proposals to funding agencies in government and industry, including NSF, DOE, ECS Amazon Catalyst, and Samsung global research outreach. My research capabilities include:

• Developing physics-based battery models for the present and the next-generation batteries (e.g., lithium-ion, lithium metal, and flow batteries)
• Validating physics-based models with experimental data and analyzing chemical/physical phenomena with mathematical models
• Combining data science tools with model-based approaches
• Identifying efficient ways to integrate batteries with renewable energy applications for cost-effective systems (e.g., renewable grids and electric vehicles).

Teaching Interests:

I have degrees in Chemical Engineering (Bachelor and Ph.D.) and Chemistry (M.S.). I am confident in my abilities to teach the core Chemical Engineering curriculum from the perspectives of engineers as well as scientists.

∙ Core chemical engineering curriculum: mathematical methods in engineering, chemical reaction engineering, process control, transport phenomena, and thermodynamics at the undergraduate and graduate levels.

Also, my research background makes me well placed to develop and teach technical electives, which are invaluable from the perspective of current employment in industry and performing academic research (e.g., data science and battery/ grid integration).

∙ Technical electives: Electrochemical engineering, microgrid architectures and controls, renewable energy storage/conversion systems, and data science for chemical engineering and material science.