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- Creators: Crozier, Peter
- Creators: Hedman, Kory
- Member of: Theses and Dissertations
- Status: Published
Description
Battery energy storage has shown a lot of potential in the recent past to be effective in various grid services due to its near instantaneous ramp rates and modularity. This thesis aims to determine the commercial viability of customer premises and substation sited battery energy storage systems. Five different types of services have been analyzed considering current market pricing of Lithium-ion batteries and power conditioning equipment. Energy Storage Valuation Tool 3.0 (Beta) has been used to exclusively determine the value of energy storage in the services analyzed. The results indicate that on the residential level, Lithium-ion battery energy storage may not be a cost beneficial option for retail tariff management or demand charge management as only 20-30% of the initial investment is recovered at the end of 15 year plant life. SRP's two retail Time-of-Use price plans E-21 and E-26 were analyzed in respect of their ability to increase returns from storage compared to those with flat pricing. It was observed that without a coupled PV component, E-21 was more suitable for customer premises energy storage, however, its revenue stream reduces with addition to PV. On the grid scale, however, with carefully chosen service hierarchy such as distribution investment deferral, spinning or balancing reserve support, the initial investment can be recovered to an extent of about 50-70%. The study done here is specific to Salt River Project inputs and data. Results for all the services analyzed are highly location specific and are only indicative of the overall viability and returns from them.
ContributorsNadkarni, Aditya (Author) / Karady, George G. (Thesis advisor) / Ayyanar, Raja (Committee member) / Hedman, Kory (Committee member) / Arizona State University (Publisher)
Created2013
Description
Lithium ion batteries are quintessential components of modern life. They are used to power smart devices — phones, tablets, laptops, and are rapidly becoming major elements in the automotive industry. Demand projections for lithium are skyrocketing with production struggling to keep up pace. This drive is due mostly to the rapid adoption of electric vehicles; sales of electric vehicles in 2020 are more than double what they were only a year prior. With such staggering growth it is important to understand how lithium is sourced and what that means for the environment. Will production even be capable of meeting the demand as more industries make use of this valuable element? How will the environmental impact of lithium affect growth? This thesis attempts to answer these questions as the world looks to a decade of rapid growth for lithium ion batteries.
ContributorsMelton, John (Author) / Brian, Jennifer (Thesis director) / Karwat, Darshawn (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Lithium conducting garnets in the family of Li7La3Zr2O12 (LLZO) are promising lithium conductors for solid-state batteries, due to their high ionic conductivity, thermal stability, and electrochemical stability with metallic lithium. Despite these advantages, LLZO requires a large energy input to synthesize and process. Generally, LLZO is synthesized using solid-state reaction (SSR) from oxide precursors, requiring high reaction temperatures (900-1000 °C) and producing powder with large particle sizes, necessitating high energy milling to improve sinterability. In this dissertation, two classes of advanced synthesis methods – sol-gel polymer-combustion and molten salt synthesis (MSS) – are employed to obtain LLZO submicron powders at lower temperatures. In the first case, nanopowders of LLZO are obtained in a few hours at 700 °C via a novel polymer combustion process, which can be sintered to dense electrolytes possessing ionic conductivity up to 0.67 mS cm-1 at room temperature. However, the limited throughput of this combustion process motivated the use of molten salt synthesis, wherein a salt mixture is used as a high temperature solvent, allowing faster interdiffusion of atomic species than solid-state reactions. A eutectic mixture of LiCl-KCl allows formation of submicrometer undoped, Al-doped, Ga-doped, and Ta-doped LLZO at 900 °C in 4 h, with total ionic conductivities between 0.23-0.46 mS cm-1. By using a highly basic molten salt medium, Ta-doped LLZO (LLZTO) can be obtained at temperatures as low as 550 °C, with an ionic conductivity of 0.61 mS cm-1. The formation temperature can be further reduced by using Ta-doped, La-excess pyrochlore-type lanthanum zirconate (La2Zr2O7, LZO) as a quasi-single-source precursor, which convert to LLZTO as low as 400 °C upon addition of a Li-source. Further, doped pyrochlores can be blended with a Li-source and directly sintered to a relative density up to 94.7% with high conductivity (0.53 mS cm-1). Finally, a propensity for compositional variation in LLZTO powders and sintered ceramics was observed and for the first time explored in detail. By comparing LLZTO obtained from combustion, MSS, and SSR, a correlation between increased elemental inhomogeneity and reduced ionic conductivity is observed. Implications for garnet-based solid-state batteries and strategies to mitigate elemental inhomogeneity are discussed.
ContributorsWeller, Jon Mark (Author) / Chan, Candace K (Thesis advisor) / Crozier, Peter (Committee member) / Sieradzki, Karl (Committee member) / Arizona State University (Publisher)
Created2021