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NASA/TM—2017–219686

A Novel Solid State Ultracapacitor

A. Y . C ortés-Peña Johnson Space Center, Houston, Texas

T . D. Rolin and S.M. Strickland Marshall Space Flight Center, Huntsville, Alabama

C.W. Hill CK T e chnologies, Meridianville, Alabama

August 2017

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NASA/TM—2017–219686

A Novel Solid State Ultracapacitor

A. Y . C ortés-Peña Johnson Space Center, Houston, Texas

T . D. Rolin and S.M. Strickland Marshall Space Flight Center, Huntsville, Alabama

C.W. Hill CK T e chnologies, Meridianville, Alabama

National Aeronautics and Space Administration

Marshall Space Flight Center • Huntsville, Alabama 35812

August 2017

i

Acknowledgments

A.Y. Cortés-Peña thanks Terry D. Rolin for his invaluable guidance and insight into this project as her mentor. She also thanks NASA’s Motivating Undergraduates in Science Technology Program and the Hispanic Scholarship Fund for making her internship possible. She also thanks Mark Strickland, Patrick Mcmanus, Curtis Hill, Kathy Pressnell, Lee Allen, David Geist, Furman Thompson, Ron Hodge, Angela Shields, Angie Thoren, and staff in ES43 for supporting her project. This work has been paid in part by the Electrical, Electronic, and Electromechanical Parts, Packaging, and Fabrication Branch (ES43), the Center Innovation Fund, several NASA Marshall Space Flight Center Project Offices and has been funded by the NASA Georgia Space Grant.

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Available from:
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Mail Stop 148
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This report is also available in electronic form at
<http://www.sti.nasa.gov>

ii

TABLE OF CONTENTS

1. INTRODUCTION ............................................................................................................. 2. BACKGROUND ................................................................................................................
12
2.1 Conventional Capacitors .............................................................................................. 2.2 Electrochemical Double-Layer Capacitor ..................................................................... 2.3 Internal Barrier Layer Capacitor ..................................................................................
246

  • 3. METHODOLOGY ............................................................................................................
  • 8

3.1 Atomic Layer Deposition-Coated Ceramic Barium Titanate Nanoparticles ................. 3.2 High-Temperature and Reduced Forming Gas Sintering ..............................................
89
3.3 Pellet Electrical Characterization .................................................................................. 11 3.4 Dielectric Ink Formulation ........................................................................................... 12 3.5 3D Additive Thick Film Deposition ............................................................................. 12 3.6 Thick Film Electrical Characterization ......................................................................... 14

4. ANALYSIS ......................................................................................................................... 15
4.1 Pellet Electrical Characterization .................................................................................. 15 4.2 Thick Film Electrical Characterization ......................................................................... 20

5. CONCLUSIONS ................................................................................................................ 26 REFERENCES ....................................................................................................................... 28

iii

LIST OF FIGURES

1. 2.

  • Schematic of a conventional capacitor .......................................................................
  • 2

Ragone chart of energy storage devices. Source: Defense Logistics Agency Land

  • and Maritime .............................................................................................................
  • 5

679
3. 4. 5. 6.
Schematic of an EDLC .............................................................................................. IBLC effect ................................................................................................................ BaTiO nanoparticle with 5 nm of SiO coating ........................................................

  • 3
  • 2

The BaTiO crystal structure. The green, red, and blue atoms are titanium,

3

oxygen, and barium, respectively. Source: <www.crystalmaker.com> ........................ 10

  • 7.
  • Dielectric Test Fixture 1645-1B (bottom) and Agilent E4980A precision LCR

meter (top) ................................................................................................................. 11

8. 9.
Top and side views of the ultracapacitor module layers ............................................. 13 Eight-zone belt furnace temperature settings ............................................................. 13 Belt furnace temperature profile ................................................................................. 14 SEM images of BaTiO (a) uncoated from TPL, (b) coated with Al O ,
10. 11.

  • 3
  • 2
  • 3

and (c) Al O -coated treated at 750 °C for 30 hr ........................................................ 15

  • 2
  • 3

12. 13. 14. 15.
Optical microscopy photographs of untreated (a) uncoated, (b) SiO -coated,

2

and (c) Al O -coated BaTiO pellets .......................................................................... 15

  • 2
  • 3
  • 3

Optical microscopy photographs of (a) uncoated, (b) SiO -coated,

2

and (c) Al O -coated BaTiO pellets treated at 900 °C for 1 hr .................................. 16

  • 2
  • 3
  • 3

Optical microscopy photographs of (a) uncoated, (b) SiO -coated,

2

and (c) Al O -coated BaTiO pellets treated at 1,100 °C for 1 hr ............................... 16

  • 2
  • 3
  • 3

Plots of (a) permittivity, (b) DF, and (c) ESR samples treated at 900 °C for 15 hr and 1,100 °C for 1 hr compared to the untreated powders ......................................... 17

iv

LIST OF FIGURES (Continued)

16. 17. 18. 19.
Plots of (a) permittivity, (b) DF, and (c) ESR samples treated at 900 °C for 1 hr compared to the untreated powders ............................................................... 19

Ultracapacitor test cell made from SiO -coated BaTiO deposited by screen

  • 2
  • 3

printing ...................................................................................................................... 20 Plots of (a) permittivity, (b) DF, and (c) ESR plots of powdered samples treated at 900 °C for 1 hr before and after furnace sintering .................................................. 21

SEM image showing a 75% densification and the porosity of SiO -coated BaTiO

  • 2
  • 3

test cell with 184 nF of capacitance ........................................................................... 22 Voltage versus time plot used for the discharge method ............................................. 23 Breakdown curves for a device exhibiting breakdown >500 V ................................... 24
20. 21.

  • 22.
  • Plots of (a) capacitance, (b) DF, and (c) ESR the capacitor test cells, made from

the dielectric material treated at 900 °C for 1 hr before and after furnace sintering ........................................................................................................ 25

23. 24.
Ultracapacitor cells in parallel .................................................................................... 27 Ultracapacitor package............................................................................................... 27

v

LIST OF TABLES

1. 2. 3. 4. 5. 6. 7.
Model for corresponding capacitance ranges .............................................................. Ultracapacitor/Battery comparison .............................................................................
36

  • 8
  • BaTiO materials ........................................................................................................

3

Dielectric ink formulation ........................................................................................... 12 Furnace nitrogen flow profile ...................................................................................... 14 Synthesis profile effect on dielectric permittivity ......................................................... 18 SiO -coated BaTiO capacitor test cell characteristics ................................................. 23

  • 2
  • 3

vi

LIST OF ACRONYMS, SYMBOLS, AND ABBREVIATIONS

  • AC
  • alternating current

AgZn Al O silver zinc alumina

  • 2
  • 3

  • ALD
  • atomic layer deposition

  • barium titanate
  • BaTiO

DC

3

direct current

  • DF
  • dissipation factor

EEE EDLC ESR electrical, electronic, and electromechanical electrochemical double-layer capacitor equivalent series resistance

  • hydrogen gas
  • H

2

HESSCap IBLC high energy solid state capacitor internal barrier layer capacitor inductance, capacitance, resistance lithium-ion
LCR Li-ion

  • N
  • nitrogen gas

2

  • O
  • oxygen

PdAg SEM palladium silver scanning electron microscopy

vii

LIST OF ACRONYMS, SYMBOLS, AND ABBREVIATIONS (Continued)

  • Si
  • silicon

  • SiO
  • silica

2

SPS Ti spark plasma sintering titanium

viii

NOMENCLATURE

A C D E e

surface area capacitance distance energy electron

f

frequency current

I j

imaginary part of impedance power

P P

maximum power stored charge resistance, resistor time

max

Q R t

tan δ loss tangent delta

voltage

V V

final voltage initial voltage reactance

f

V

i

X Z

impedance ix

NOMENCLATURE (Continued)

εεε

vacuum permittivity effective permittivity relative permittivity

0eff

r

x
TECHNICAL MEMORANDUM

A NOVEL SOLID STATE ULTRACAPACITOR
1. INTRODUCTION

NASA analyzes, tests, packages, and fabricates electrical, electronic, and electromechanical (EEE) parts used in space vehicles. One area that NASA wishes to advance is energy storage and delivery. Currently, space vehicles use rechargeable batteries that utilize silver zinc (AgZn) or lithium ion (Li-ion) electrochemical processes. These current state-of-the-art rechargeable batteries cannot be rapidly charged, contain harmful chemicals, and suffer from early wear-out mechanisms. A solid state ultracapacitor is an EEE part that offers significant advantages over current electrochemical and electrolytic devices. The objective of this research is to develop an internal barrier layer capacitor (IBLC) using novel dielectric materials as a battery replacement with a focus on such advantages as longer life, lower mass-to-weight ratio, rapid charging, on-demand pulse power, improved on-pad standby time without maintenance, and environmental friendliness.

Ultracapacitor behavior has been reported in a number of oxides including reduced barium titanate (BaTiO ) ferroelectric ceramics. BaTiO is a ceramic material in the perovskite family that

  • 3
  • 3

possesses a high dielectric constant. Individual coating of ferroelectric BaTiO grains with a silica

3

(SiO ) shell followed by spark plasma sintering (SPS) in reducing conditions has been shown to

2
5

lead to stable ultracapacitor behavior. The permittivity values have been reported to be ≈10 in electroceramics. It has also been shown that treating oxidized BaTiO at high temperatures in reduc-

1
3

ing forming gas atmosphere (96% nitrogen gas (N ), 4% hydrogen gas (H )) produces an N-type

  • 2
  • 2

2

semiconducting material. The outer coating, which remains an insulating shell, combines with this semiconducting internal layer, resulting in millions of nanocapacitors in parallel. The combination of a semiconducting grain with an insulating boundary leads to the IBLC effect.

These so-called giant ultracapacitor properties are not easily controlled. The American
Piezo Ceramics International reports a relative dielectric constant of 1,550 and a dielectric dis-

3

sipation factor (DF) of 0.5 for single crystal BaTiO . High permittivity values such as relative

3

permittivity ε ≈10,000 are reported in polycrystalline ferroelectric BaTiO . Reduced BaTiO of

r

  • 3
  • 3

5 4

grain sizes between 70 and 300 nm have yielded colossal permittivity values in the order of 10 . The purpose of this study is to evaluate shell-coated BaTiO processed under reducing conditions

3

to produce the IBLC effect.
1

2. BACKGROUND
2.1 Conventional Capacitors

A capacitor is an electrical component consisting of two conducting electrodes separated by an insulating dielectric material. When voltage is applied across the capacitor, opposite charges accumulate on the surface of each electrode, developing a static electric field. This field causes atoms in the insulator to polarize, producing an internal electric field. Capacitors are able to store energy in this overall electric field. This is illustrated in figure 1.

Dielectric

+++++++++

–––––––––
– + – + – + – + – + – + – + – + – + – + – + – + – + – + – + – + – + – + – + – + – + – + – + – + – + – + – +

Positive Electrode
Negative Electrode

Load
Resistance
Electric Field

–

+

Applied Voltage

5

Figure 1. Schematic of a conventional capacitor.
Capacitance is a measure of the ability to store charge, and it is the ratio of the stored charge Q to the applied voltage V:

Q V

.

(1)

C =

The capacitance can be improved by increasing the electrode surface area A and decreasing the distance between the plates. It is also proportional to the ε , which measures how much electric flux

r

is generated per unit charge, and it is directly related to how easily a specific material polarizes in response to an electric field. The vacuum permittivity ε is a constant due to free space vacuum and

0

2

–12

is 8.854187…× 10 F/m. The relative permittivity multiplied by the vacuum permittivity is usually called the effective permittivity ε :

eff

A D

  • .
  • (2)

C = ε ε

0 r

Capacitive loads oppose the change of voltage. Impedance Z is a measure of the effect of capacitive loads. When reactance X is zero, the load is purely resistive; when resistance R is zero, the load is purely reactive. Ideal capacitors consist entirely of reactance, having infinite resistance:

Z = R+ꢀjX

(3) and

1

X =

C

.

(4)

2πfC

Loads are modeled as either series or parallel combination of a resistive and a reactive load.
The parallel resistance is typically larger than the series resistance. To measure small reactive values, such as high-valued capacitors, it is preferable to use the series model because the series resistance is more significant than the parallel resistance. When measuring large reactive values, such as high-valued inductors or low-valued capacitors, it is preferable to use the parallel model. Table 1

6

shows the capacitance ranges and which model should be used.
Table 1. Model for corresponding capacitance ranges.

Range

>100 µF

Impedance (Ω)

<10

Model

Series
10–10,000
10,000
Series or parallel
Parallel
10 nF–100 µF
<10 nF

At low frequencies, a capacitor is an open circuit, as no current flows in the dielectric.
A direct current (DC) voltage applied across a capacitor causes positive charge to accumulate on one side and negative charge to accumulate on the other side; due to the accumulated charge, the electric field is the source of the opposition to the current. When the potential associated with the charge exactly balances the applied voltage, the current goes to zero. Driven by an alternating current (AC) supply, a capacitor will only accumulate a limited amount of charge before the potential difference changes polarity and the charge dissipates. The higher the frequency, the less charge will

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    * "4 United States Patent [191 [II] Patent Number: 4,575,690 Walls et al. [45] Date of Patent: Mar. 11, 1986- [54] ACCELERATION INSENSITIVE 4,453,141 6/1984 Rosati .................................. 32 1/1 LS OSCILLATOR Primary Exatnitrer-Eugene R. LaRoche [75] Inventors: Fred L. Walls, Boulder, Colo.; John Assislatrr Exatttitrer-Jnnies C. Lee R. Vig, Colts Neck, N.J. Attorney, Agent, or Finn-Anthony T. Lane; Jeremiah G. Murray; John T. Rehberg I731 Assignee: The United Stated of America 81 represented by the Secretary of the P71 ABSTRACT Army, Wildiiligt(w, D.C. A crystiil oscill:itor, iiiclutliiig Itvo cryst:tls 01' uticq~i;il [21] Appl. No.: 715,862 acceleration sensitivity niiigiiitude illid mounted such 1 that their respective acceleration sensitivity vectors are [22] Filed: Mar. 25, 1985 aligned in an anti-parallel relationship, further includes at least one electrical reactance, such as a variable CB- [51] Int. c1.4 ............................................... H03B 5/32 [52] US. C1. ................................ 331/162; 331/116 R; pacitor, coupled to one of the crystals for providing 331/158 cancellation of acceleration sensitivities. After the ac- I581 Field of Search ....................... 310/311, 360, 361; celeration sensitivity vectors of the two crystals are 331/116 R, 158, 160, I62 aligned anti-parallel, the variiible capacitor is ad.jiisted until the iict or result;int accclcr:itioii sciisitivity vccior ~561 References Cited of the pair of resonators is reduced to zero. A second U.S. PATENT DOCUMENTS electrical reactance, such ils a vari;ible capacitor, is utilized as a tuning capacitor for adjusting the oscilla- 3,978,432 8/1916 Onw ..................................
  • Modelling of Distorted Electrical Power and Its Practical Compensation in Industrial Plant

    Modelling of Distorted Electrical Power and Its Practical Compensation in Industrial Plant

    MODELLING OF DISTORTED ELECTRICAL POWER AND ITS PRACTICAL COMPENSATION IN INDUSTRIAL PLANT By JAN HARM CHRISTIAAN PRETORIUS THESIS presented in partial fulfilment of the requirements for the degree DOCTOR 1NGENERIAE ' (D. Ing) in the FACULTY OF ENGINEERING of the RAND AFRIKAANS UNIVERSITY SUPERVISOR: PROF. J.D. van WYK CO-SUPERVISOR: DR. P.H. SWART DECEMBER 1997 11 PREFACE Alternating current systems employing single-frequency sinusoidal waveforms render optimal service when the currents in that system are also sinusoidal and have a fixed phase relationship to the voltages that drive them. Under unity- power factor conditions, the currents are in phase with the voltages and optimal net-energy transfer takes place under minimum loading conditions, i.e. with the lowest effective values of current and voltage in the system. The above conditions were realised in the earlier years, because supply authorities generated 50 Hz sinusoidal voltages and consumers drew 50 Hz sinusoidal currents with fixed phase relationships to these voltages. Static and rotating electrical equipment like transformers, motors, heating and lighting equipment were equally compatible with this requirement and well-behaved AC networks were more the rule than the exception. The fact that three-phase systems conveyed the bulk of the power from one topographical location to the next did not constrain the utilisation of that concept at all, even though poly-phase transmission systems were necessary to increase the economy of transmission and to furnish non-pulsating power transfer. Also, additional theory had to be developed to handle unbalanced conditions in these multi-phase systems and to take care of complex network analysis and fault conditions.
  • Title Electrical Reactance and Its' Correlates In

    Title Electrical Reactance and Its' Correlates In

    TITLE ELECTRICAL REACTANCE AND ITS' CORRELATES IN BIOLOGICAL SYSTEMS BY NELSON W. C. NMD LPCC AND NIEBER, JOZSEF HIPPOCAMPUS INSTITUTE BUDAPEST , HUNGARY 1995 ABSTRACT: In this short paper we review some of the basic principle of reactance and draw correlates to reactivity in biological systems. Biological organisms indeed have electrical capacities. Electronic stability is important for every cell in maintaining its' life. Reactance is one way that the cell could react with its external environment. This article draws correlates to cell membrane capacitance and inductance changes as possible ways of understanding the electronic function of a cell . Thus classical electronic theory could be used to describe the phenomena of cell reactivity. This has offered potentials for deeper development of bio electronic device interface, and diagnostic medical instrumentation. page 1 REVIEW OF ELECTRONIC REACTIVITY INTRODUCTION: Reactance was first described as the ability of an electronic circuit to react to voltage and amperage changes. Reactance allows us to understand the range of responsiveness of a circuit as well as its sensitivities. In fact Reactance is a correlate to sensitivity in a circuit. The voltage and amperage changes applied to a circuit effect and are effected by the capacitance and inductance of the circuit. These determine the then the reactance or range of sensitivity of the circuit and set response characteristics of the circuit. In the Handbook of Electronic Tables and Formulas (Sams & Co.) (ref. 1986 ), reactance is defined now as opposition to the flow of alternating current by the inductance or capacitance of a component or circuit. The handbook further defines capacitance reactance differing from inductance reactance.

  • Instrumentation and Control Qualification Standard

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