Next Article in Journal
Potential Impact of Renewable Energy on the Sustainable Development of Russian Arctic Territories
Previous Article in Journal
Rooftop PV: Potential and Impacts in a Complex Territory
Article

Series-Parallel Reconfigurable Electric Double-Layer Capacitor Module with Cell Equalization Capability, High Energy Utilization Ratio, and Good Modularity

College of Engineering, Ibaraki University, Hitachi 316-8511, Japan
*
Author to whom correspondence should be addressed.
Academic Editor: Francesco Lufrano
Energies 2021, 14(12), 3689; https://doi.org/10.3390/en14123689
Received: 11 May 2021 / Revised: 9 June 2021 / Accepted: 18 June 2021 / Published: 21 June 2021
(This article belongs to the Section D: Energy Storage and Application)
Voltages of electric double-layer capacitor (EDLC) modules vary rather wider than traditional secondary batteries. Although EDLCs should desirably be cycled in a voltage range as wide as possible to achieve a high energy utilization ratio, the wide voltage variation of EDLC modules impairs the performance of DC–DC converters. To address such issues, previous works reported series-parallel reconfiguration techniques, which are roughly divided into balance- and unbalance-shift circuits. However, conventional balance-shift circuits are not applicable to modules comprising odd number cells, impairing modularity. Unbalance-shift circuits, on the other hand, unavoidably cause cell voltage imbalance that reduces energy utilization ratio. This paper proposes a novel series-parallel reconfigurable EDLC module with cell voltage equalization capability. The proposed reconfigurable EDLC module is applicable to any number of cells, realizing good modularity. Furthermore, all cells in the proposed module can be charged and discharged uniformly without generating cell voltage imbalance, achieving an improved energy utilization ratio compared with conventional techniques. A five-cell module prototype was built for experimental verification. While the module voltage varied between 1.04 and 2.83 V, all cells discharged from 2.5 to 0.3 V. The result is equivalent to a 98.6% energy utilization ratio. View Full-Text
Keywords: electric double-layer capacitor (EDLC); energy utilization ratio; series-parallel reconfiguration; voltage equalization electric double-layer capacitor (EDLC); energy utilization ratio; series-parallel reconfiguration; voltage equalization
Show Figures

Figure 1

MDPI and ACS Style

Uno, M.; Lin, Z.; Koyama, K. Series-Parallel Reconfigurable Electric Double-Layer Capacitor Module with Cell Equalization Capability, High Energy Utilization Ratio, and Good Modularity. Energies 2021, 14, 3689. https://doi.org/10.3390/en14123689

AMA Style

Uno M, Lin Z, Koyama K. Series-Parallel Reconfigurable Electric Double-Layer Capacitor Module with Cell Equalization Capability, High Energy Utilization Ratio, and Good Modularity. Energies. 2021; 14(12):3689. https://doi.org/10.3390/en14123689

Chicago/Turabian Style

Uno, Masatoshi, Ziyan Lin, and Kakeru Koyama. 2021. "Series-Parallel Reconfigurable Electric Double-Layer Capacitor Module with Cell Equalization Capability, High Energy Utilization Ratio, and Good Modularity" Energies 14, no. 12: 3689. https://doi.org/10.3390/en14123689

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop