1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T L.1222 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (05/2018) SERIES L: ENVIRONMENT AND ICTS, CLIMATE CHANGE, E-WASTE, ENERGY EFFICIENCY; CONSTRUCTION, INSTALLATION AND PROTECTION OF CABLES AND OTHER ELEMENTS OF OUTSIDE
2、PLANT Innovative energy storage technology for stationary use Part 3: Supercapacitor technology Recommendation ITU-T L.1222 ITU-T L-SERIES RECOMMENDATIONS ENVIRONMENT AND ICTS, CLIMATE CHANGE, E-WASTE, ENERGY EFFICIENCY; CONSTRUCTION, INSTALLATION AND PROTECTION OF CABLES AND OTHER ELEMENTS OF OUTSI
3、DE PLANT OPTICAL FIBRE CABLES Cable structure and characteristics L.100L.124 Cable evaluation L.125L.149 Guidance and installation technique L.150L.199 OPTICAL INFRASTRUCTURES Infrastructure including node elements (except cables) L.200L.249 General aspects and network design L.250L.299 MAINTENANCE
4、AND OPERATION Optical fibre cable maintenance L.300L.329 Infrastructure maintenance L.330L.349 Operation support and infrastructure management L.350L.379 Disaster management L.380L.399 PASSIVE OPTICAL DEVICES L.400L.429 MARINIZED TERRESTRIAL CABLES L.430L.449 For further details, please refer to the
5、 list of ITU-T Recommendations. Rec. ITU-T L.1222 (05/2018) i Recommendation ITU-T L.1222 Innovative energy storage technology for stationary use Part 3: Supercapacitor technology Summary Recommendation ITU-T L.1222 is based on Recommendation ITU-T L.1220 and is the part related to supercapacitors.
6、Recommendation ITU-T L.1222 contains selection criteria for telecommunication application based on main performance parameters and the methods for proper use. In addition, some use cases and examples are given in an Appendix to help users. History Edition Recommendation Approval Study Group Unique I
7、D* 1.0 ITU-T L.1222 2018-05-14 5 11.1002/1000/13579 Keywords Direct current, double layer capacitor, energy storage, micro-interruptions, next generation access network, battery, supercapacitor. * To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web brows
8、er, followed by the Recommendations unique ID. For example, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T L.1222 (05/2018) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication t
9、echnologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Te
10、lecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some
11、 areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized
12、 operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words
13、“shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the
14、 practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation d
15、evelopment process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers are cautioned that this may not represent the latest information and are th
16、erefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2018 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T L.1222 (05/2018) iii Table of Contents Page 1 Scope
17、 . 1 2 References . 1 3 Definitions 1 3.1 Terms defined elsewhere 1 3.2 Terms defined in this Recommendation . 1 4 Abbreviations and acronyms 1 5 Conventions 2 6 General introduction to supercapacitors . 2 7 Working principle . 3 8 Supercapacitor technology and performance 4 9 Applications 5 10 Econ
18、omic and environmental topics . 5 Appendix I Certification information . 6 I.1 General . 6 Appendix II Application examples . 7 II.1 General . 7 Bibliography. 9 iv Rec. ITU-T L.1222 (05/2018) Introduction This Recommendation is part 3 of a series covering innovative energy storage technology for sta
19、tionary use. This series introduces the evolution of energy storage technologies applicable for use with stationary information and communication technology/telecommunication (ICT/TLC) equipment and provides global results of investigations in laboratories or from field tests in TLC/ICT network or c
20、ustomer premises (e.g., for resilience in a smart sustainable city). Mobile and portable batteries lie outside the scope of this Recommendation. Identified parts of this Recommendation series, Innovative energy storage technology for stationary use, are: Part 1: Overview of energy storage; Part 2: B
21、attery systems; Part 3: Supercapacitor technology. This Recommendation was developed jointly by ETSI TC EE and ITU-T Study Group 5 and published respectively by ITU and ETSI as Recommendation ITU-T L.1222 and ETSI Standard ETSI TS 103 533-3, which are technically equivalent. Rec. ITU-T L.1222 (05/20
22、18) 1 Recommendation ITU-T L.1222 Innovative energy storage technology for stationary use Part 3: Supercapacitor technology 1 Scope This Recommendation provides an overview of available supercapacitor (SC) technology, with details of SC characteristics (electrical, mechanical, thermal) and applicabi
23、lity in the telecommunication/information and communication technology (TLC/ICT) domain b-ETSI TR 102 532. A general overview of the evolution of energy storage technologies is provided in ITU L.1220. The adoption of SC technology is recommended for coverage of micro-interruptions of the public grid
24、 for indoor and outdoor applications. Examples of sizing and essential tests used in the network are described. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of
25、 publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list
26、 of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T L.1220 Recommendation ITU-T L.1220 (2017), Innovative energy storage technology for stationa
27、ry use Part 1: Overview of energy storage. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following term defined elsewhere: 3.2.1 electrochemical capacitor; supercapacitor b-IEC 60050-114: Device that stores energy using a double layer in an electrochemical cell. 3.2 Terms de
28、fined in this Recommendation None. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: AC Alternating Current CO Central Office DC Direct Current ELDC Electric Double Layer Capacitor FTTCab Fibre To The Cabinet FTTx Fibre To The x (x:= E = Exchange; B = Bu
29、ilding; dP = distribution Point; H = Home) 2 Rec. ITU-T L.1222 (05/2018) ICT Information Communication Technology MTBF Mean Time Between Failures NGAN Next Generation Access Network RMS Root Mean Square SC Supercapacitor SELV Safety Extra Low Voltage TLC Telecommunication UBB Ultrabroadband VAC Volt
30、 Alternating Current VDC Volt Direct Current 5 Conventions None. 6 General introduction to supercapacitors SCs store electrical energy in the form of electrical charges in two electrodes and an electric field between them. They have very low internal impedance and can be recharged in seconds. They a
31、re characterized by very high values of specific power (watts per kilogram) and are particularly suitable for peak power applications. On the other side, the specific energy (watt hours per kilogram or watt hours per litre) of SCs is much lower (about 10 times) than that of batteries and, in additio
32、n on discharge the voltage decreases from the nominal voltage to zero, thus limiting the useful energy in actual applications approximately to a quarter of the available energy (dictated by the minimum operational voltage of the apparatus). In summary, SCs are very good in providing peak power deman
33、ds, but they store low amounts of useful energy and cannot replace batteries in the majority of current applications. When integrated with a battery, SCs can significantly increase the high rate performance of storage systems and extend overall service life, as they can reduce high power drains from
34、 batteries, thus reducing battery degradation. Figure 1 shows a typical example of a high-power SC bank, e.g., for peak power shaving and Figure 2 shows a typical SC used for fibre to the x (FTTx) applications in the active access network. Rec. ITU-T L.1222 (05/2018) 3 Figure 1 Example of a supercap
35、acitor bank, 360 VDC 150 kW 320 Wh Figure 2 Examples of supercapacitors for fibre to the x (0.5 Wh at 48 VDC on left 1.6 Wh at 48 VDC on right) frontal view SC modules are installed between the alternating current/direct current (AC/DC) converter (e.g., 230 VAC/60 VDC) and the TLC load, so that the
36、TLC equipment can be powered at a safety extra low voltage (SELV) level, with primary energy source from public mains, without usage of standby batteries. These SC modules are able to provide uninterrupted power for micro-interruptions from the mains (e.g., power outages of less than few seconds), t
37、o avoid the rebooting of TLC/ICT systems (usually taking several minutes to bring back TLC/ICT service, as described in Appendix III of ITU-T L.1220). Operating temperature and cell voltage impact on SCs lifetime. High temperature and a working voltage close to the nominal voltage reduce the lifetim
38、e. Based on that, the designer can improve the lifetime by: reducing the working temperature; reducing the cell working voltage, e.g., by using more cells in series. 7 Working principle SCs are devices that are able to store more electrical energy than equivalent electrostatic capacitors. They use p
39、ositive and negative metallic plates (generally cylindrically shaped) with very large active surface and very short distance between the plates (e.g., 0.1 nm). 4 Rec. ITU-T L.1222 (05/2018) A SC consists of two electrodes, placed on aluminium supports that act as current collectors, with a dielectri
40、c separator and electrolyte between the electrodes. Electrodes are made of porous materials, to create a larger contact surface available for the electrolyte. The dielectric separator, generally made of paper, plastic or ceramic, is needed to block the transfer of electrons inside the SC, meanwhile
41、offering a high permeability for electrolyte ions. A potential difference, applied across the terminals of a SC, starts a process of separation of electrolyte ions, which generates a double layer of charge on the electrode/electrolyte interfaces. In particular, the voltage applied causes electrons t
42、o gather on the positive electrode and to the deposition of positive ionic charge on the interface with the electrolyte. In a similar way, a surplus of positive charges will be present on the negative electrode and negative ionic charge will reside on the interface with the electrolyte (see Figure 3
43、). In SCs the storage of energy is performed through a reversible process of very quick charge transfer, without redox chemical processes. This allows fast charge and discharge of SCs, with a higher number of lifecycles compared to traditional electrochemical capacitors. The very short distance betw
44、een the two electrodes results in high values for the internal electrical fields, whose strength can approach the dielectric strength of the dielectric material. This implies the adoption of a voltage limitation between the electrodes and of the associated stored energy. SCs are devices that are abl
45、e to give high levels of power in a short time, and with very high numbers of charge and discharge cycles. These features of SCs allow them to be used in applications, such as compensation for power fluctuations in the electrical grids and for voltage regulation (power quality application, to improv
46、e voltage waveform). Figure 3 Cylindrical supercapacitor and schematic of the double layer of charge 8 Supercapacitor technology and performance Table 1 provides data on the main SC performance parameters. The nominal voltage of an SC cell is dependent on its construction and the type of electrolyte
47、 (higher for organic electrolytes and lower for aqueous ones). SC specific energy is very low in general, since these devices are mainly intended to be used against transient power interruptions, not for energy back-up. Expected cycling lifetime, can reach values in the range of 500 000 to 1 000 000
48、 cycles (with voltage ranging from a maximum value to half maximum during the working cycle). Rec. ITU-T L.1222 (05/2018) 5 Table 1 SC performance parameters Parameter Typical values Nominal Voltage (V) 1-2.7 Capacity (F) 1-5000 Specific power (W/kg) 300-100 000 Specific energy (Wh/kg) 0.5-10 Energy
49、 efficiency (%) 95-98 Daily self-discharge (%) 20-40 Expected life-time (years) 5-10 Number of cycles 50 000 Temperature operating range (C) 40-65 Auxiliary system balancing system of the cell NOTE The lifetime is impacted by the capacitor temperature and root mean square (RMS) current, as high values can increase the working temperature. 9 Applications Applications for SC technology are related to next generation access networks (NGANs), using active loads spread outside traditional central offices (COs). In such a sc
