JournalTOCs

About Help News

eTransportation
Number of Followers: 2

This is an Open Access Journal

Open Access journal
ISSN (Online) 2590-1168
Published by Elsevier

[3203 journals]

Wayside energy recovery systems in DC urban railway grids
- Abstract: Publication date: August 2019Source: eTransportation, Volume 1Author(s): Fabian Meishner, Dirk Uwe SauerAbstractIn modern electrified and rail-bound mass transit vehicles, a considerable part of the braking energy is still dissipated via resistors. This applies in particular to less connected and low frequented grid sections. For this purpose, wayside energy recovery systems can be used to store excess energy and release it during acceleration of nearby vehicles. They offer further advantages, such as a potential reduction in the power requirement of substations or additional safety and reliability. This paper provides an overview of actual demonstrations of various systems in public transport grids. The focus is on the most important technologies (namely: supercaps, flywheels, batteries and inverters), as well as the respective manufacturers and products. The achievable improvements, based on both real demonstrations and scientific studies, are identified and critically evaluated. Important points for a better assessment of the systems are worked out. A future forecast is given for each of the four technologies.
Lithium-ion battery fast charging: A review
- Abstract: Publication date: August 2019Source: eTransportation, Volume 1Author(s): Anna Tomaszewska, Zhengyu Chu, Xuning Feng, Simon O'Kane, Xinhua Liu, Jingyi Chen, Chenzhen Ji, Elizabeth Endler, Ruihe Li, Lishuo Liu, Yalun Li, Siqi Zheng, Sebastian Vetterlein, Ming Gao, Jiuyu Du, Michael Parkes, Minggao Ouyang, Monica Marinescu, Gregory Offer, Billy WuAbstractIn the recent years, lithium-ion batteries have become the battery technology of choice for portable devices, electric vehicles and grid storage. While increasing numbers of car manufacturers are introducing electrified models into their offering, range anxiety and the length of time required to recharge the batteries are still a common concern. The high currents needed to accelerate the charging process have been known to reduce energy efficiency and cause accelerated capacity and power fade. Fast charging is a multiscale problem, therefore insights from atomic to system level are required to understand and improve fast charging performance. The present paper reviews the literature on the physical phenomena that limit battery charging speeds, the degradation mechanisms that commonly result from charging at high currents, and the approaches that have been proposed to address these issues. Special attention is paid to low temperature charging. Alternative fast charging protocols are presented and critically assessed. Safety implications are explored, including the potential influence of fast charging on thermal runaway characteristics. Finally, knowledge gaps are identified and recommendations are made for the direction of future research. The need to develop reliable onboard methods to detect lithium plating and mechanical degradation is highlighted. Robust model-based charging optimisation strategies are identified as key to enabling fast charging in all conditions. Thermal management strategies to both cool batteries during charging and preheat them in cold weather are acknowledged as critical, with a particular focus on techniques capable of achieving high speeds and good temperature homogeneities.

JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762

Your IP address: 18.204.42.98

Home (Search)
API
About JournalTOCs
News (blog, publications)