1. Energy Harvesting Day 4: Energy Storage
April 18, 2013 Paul Nickelsberg Orchid Technologies Engineering and Consulting, Inc.

2. Energy Harvesting Review
Energy harvesting is the process of capturing trace amounts of naturally occurring energy from various sources.
Accumulating the Energy
Storing the Energy
Applying the Energy for Useful Purpose

3. Energy Storage Battery Energy Storage Super Capacitor Energy Storage
Reservoir Energy Storage 3

4. Battery Energy Storage
Shapes and Sizes 4

5. Battery Energy Storage
Chemistry types
Source: Wikipedia 5

6. Battery Energy Storage
Chemistry types
Source: Wikipedia 6

7. Battery Energy Storage
Manganese Titanium Lithium
Source: Panasonic 7

8. Battery Energy Storage
Nickel Metal Hydride (NiMh)
Source: Panasonic 8

9. Battery Energy Storage
Rechargeable
Lithium Ion (LiI)
Source: Varta 9

10. Battery Energy Storage
Primary
Lithium Ion (LiI)
TLL /2AA
Source: Tadiran 10

11. Battery Energy Storage
Rechargeable Lithium
Thin Film Battery
Source: Cymbet 11

12. Battery Energy Storage
Rechargeable Lithium
Thin Film Battery
Source: Cymbet 12

13. Super-capacitor Energy Storage
Super Capacitor Vendors
Cap-XX
NESS Cap
Maxwell Technologies, Inc 13

14. Super-capacitor Energy Storage
Source: Maxwell
Huge selection of product types 14

15. Super-capacitor Energy Storage
Huge selection of product types
Source: Nesscap 15

16. Super-capacitor Energy Storage
Electrochemical Double Layer Capacitor (ELDC)
- Electrostatic Energy Storage is non-chemical
non-reactive
- Porous Carbon Electrodes have very high
surface area
- Compact Charge Separation Distance
10 Angstroms
- High charge / discharge cycle count
- High reliability
Source: Maxwell 16

17. Super-capacitor Energy Storage
Electrochemical Double Layer
Capacitor (ELDC)
Vw : Working Voltage
Vmin: Minimum Discharge Voltage
Vr: Recovery Voltage
Vf: Final Voltage
C = qV
C = (Idischarge x timedischarge ) / (Vworking – Vfinal)
Source: Maxwell 17

18. Super-capacitor Energy Storage
C = (Idischarge x timedischarge ) / (Vworking – Vfinal)
Source: Cap-XXl 18

19. Super-capacitor Energy Storage
C = (Idischarge x timedischarge ) / (Vworking – Vfinal) 19

20. Super-capacitor Energy Storage
ELDC Capacitor Life Cycle
High Charge / Discharge Count
ESR Affects
- Voltage Affects 20

21. Super-capacitor Energy Storage
Source: Cap-XXl 21

22. Super-capacitor Energy Storage
Cstore ≥ [Iquiessent+leak + (Iburst * tburst * fburst)] Tstore / (Vcap – Vout)
Equation Term
Typical Values
Voltage Difference
0.7V (2.5 – 1.8)
Total Time Frame
10 Seconds
Application Current
1mA
Quiescent Current
10µA
C ≥ ( ) * 10 / (2.5 – 1.8)
C ≥ 143 mF
1mA used 1 time per second over 10 Sec 22

23. Super-capacitor Energy Storage
Icharge ≥ Iquiescent + ((Iburst * tburst) / Tstore
Equation Term
Typical Values
Total Time Period
1 Second
Total Use Interval
10 mSec
Total Application Current
1 mA
Total Quiescent Current
10 µA
I ≥ (0.001 * 0.01) / 1
I ≥ 20µA
1mA used 100 times per second 23

24. Reservoir Energy Storage24

25. Energy Storage
Come back tomorrow 25