System design considerations much like nas devices

Info icon This preview shows pages 26–27. Sign up to view the full content.

System Design Considerations Much like NaS devices, these systems typically come in modules with higher power and energy capacity than most secondary batteries, and are generally assembled into series/parallel connections of those modules. Self-discharge The system may lose 10% or more of its energy per day if the system is not cycling (due to parasitic heating requirements to maintain the device’s temperature), while it may have zero losses if the system is operational [26]. Lifetime The major factors affecting the lifetime of these devices are corrosion and a rise in internal resistance [26]. Operation The primary operation consideration is thermal in nature. The melting point for the salt used in this device is 157 C, hence this is the theoretical minimum operating temperature, but the typical range is 270-350 C. Operation is independent of changes in the ambient temperature. The battery management interface restrict the upper temperature limit to 70 C, and there is effectively no lower temperature limit [26]. Maintenance One excellent feature of this device’s failure mode is that cells typically fail to a resistance that is comparable to that of an intact cell, so a series chain of these cells may remain operational even with a number of cell failure, making systems composed of these batteries quite robust, and requiring little maintenance. In fact, there can be a failure of 5-10% of the cells in a system, and the unit could still function properly [26]. Environmental Impact All of the components in a sodium nickel chloride battery system can be recycled into new batteries, and this has been demonstrated successfully through the recycling ZEBRA battery systems [27]. Other Resources A good technical overview of these systems and some applications are given in [26] and a couple of overviews of this system can be found in [7,27]. Summary of Device Parameters The following table summarizes the available technoeconomic parameters for sodium nickel chloride batteries from a number of studies from 2000-2010. All monetary values have been adjusted to 2010 dollars. If a value is marked with “-” either the quantity was not found in the corresponding report or the way it was presented was inconsistent with the format used here. For example, the EPRI-DOE report gives total cost in $/kW or $/kWh, not a formulation that takes into account both, simultaneously. Source: Schoenung EPRI Gonzalez Schoenung Chen 2003 [5] 2003 [2] 2004 [3] 2008 [6] 2009 [7] Techno. Params. Roundtrip Efficiency [%] - - - - 85-90 Self-discharge [%Energy per day] - - - - 15 Cycle Lifetime [cycles] - - - - 2500+ Expected Lifetime [Years] - - - - 10-14 Specific Energy [Wh/kg] - - - - 100-120 Specific Power [W/kg] - - - - 150-200 Energy Density [Wh/L] - - - - 150-180 Power Density [W/L] - - - - 220-300 Costs Power Cost [$/kW] - - - - 150-300 Energy Cost [$/kWh] - - - - 100-200 PCS Cost [$/kW] 120-600* - - - - BOP Cost [$/kW] 0-120* - - - - O&M Fixed Cost [$/kW-y] 23-61* - - - - * indicates assumptions from NaS systems.
Image of page 26

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

Image of page 27
This is the end of the preview. Sign up to access the rest of the document.
  • One '14
  • Energy storage

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern