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Lithium-ion battery second life usage might be an interesting solution for certain applications and it can bring not only environmental benefits but also e.g. lower electric vehicles or hybrid electric vehicles total cost of ownership. However, the electrical performance and performance degradation of the battery systems in the second life application are still unknown what brings significant economic risk and hinders second life battery usage. This work investigates the capacity and power degradation of the 2.5Ah nanophosphate LiFePO4/C cells under different the second life calendar ageing regimes.

Lithium Sulfur batteries are receiving a lot of research interest because of their intrinsic characteristics, such as very high energy density and increased safety, which make them a suitable solution for zero-emission vehicles and space application. This paper analyses the influence of the temperature on the performance parameters of a 3.4 Ah Lithium-Sulfur battery cell. Furthermore, the values of the internal resistance and entropic heat coefficient, which are necessary for the parametrization of a heat generation model, are determined experimentally.

Lithium-ion batteries have already gained acceptability for Electric Vehicles (EVs) and Hybrid Electric Vehicles (HEVs) applications because of several reasons such as high theoretical capacity, their cycle-life, and high specific energy density. The intention of this experimental research is to study the surface temperature evolution of a 13 Ah Nano Lithium-Titanate battery cell for the usage of rechargeable energy storage system under fast charging conditions. The nominal voltage of the cell is 2.26V and the nominal capacity is 13.4 Ah. In this research, contact thermocouples were employed in order to measure the surface temperature evolution of the cell. A relatively non-uniform temperature distribution was observed over the cell surface.The position of the maximum temperature was seen around the negative tab of the cell.

Despite the cost of li-ion batteries is gradually falling, the price for li-ion batteries is still too high in order to significantly impact the mass market adoption of e-mobility and household battery applications. It is expected that it might take another several years before lithium-ion batteries obtain grid parity and Electric Vehicles (EVs) will become competitive in cost with conventional vehicles (Figure 1). In consequence, a different approach for battery cost reduction can be investigated.

The impedance behavior of a 3.4 Ah pouch Lithium-Sulfur cell was extensively characterized using the electrochemical impedance spectroscopy (EIS) technique. EIS measurements were performed at various temperatures and over the entire state-of-charge (SOC) interval without applying a superimposed DC current. The obtained results have revealed a high dependency of the pouch cell’s impedance spectrum on the operating conditions. An equivalent electrical circuit was proposed to further analyze the results and to quantify the contributions of different resistances to the total impedance of the Li-S pouch cell at different SOCs and temperatures.

Thermal modeling of lithium-ion batteries is gaining its importance together with increasing power density and compact design of the modern battery systems in order to assure battery safety and long lifetime. Thermal models of lithium-ion batteries are usually either expensive to develop and accurate or equivalent thermal circuit based with moderate accuracy and without spatial temperature distribution.This work presents initial results that can be used as a fundament for the cost-efficient development of the two-dimensional thermal model of lithium-ion battery based on multipoint electrothermal impedance spectroscopy.

Current lithium-ion battery research aims in not only increasing their energy density but also power density. Emerging applications of lithium-ion batteries (HEV, PHEV, grid support) are becoming more and more power demanding.The increasing charging and discharging power capability rates of lithium-ion batteries raises safety concerns and requires thermal management of the entire battery system. Moreover, lithium-ion battery’s temperature influences both battery short term (capacity, efficiency, self-discharge) and long-term (lifetime) behaviour. Thus, thermal modelling of lithium-ion battery cells and battery packs is gaining importance.Equivalent thermal circuits’ models have proven to be relatively accurate with low computational burden for the price of low spatial resolution; nevertheless, they usually require expensive equipment for parametrization.Recent research initiated by Barsoukov et al. proposed electrothermal impedance spectroscopy (ETIS) as a novel and non-destructive method of characterizing the thermal properties of batteries by defining frequency dependent thermal impedance.This paper aims to systematize the state of knowledge about ETIS, presents measurement methods on the example of a high-power LiMO2/Li4Ti5O12 battery cell and discusses the prospect.

Modern lithium-ion batteries, like LiMO2/Li4Ti5O12 chemistry, are having very high power capability, which drives the need for precise thermal modelling of the battery. Battery thermal models are required to avoid possible safety issues (thermal runaways, high-temperature gradients) but also for the optimal battery pack design and for predicting battery electrical performance during operation (especially at low temperatures). Equivalent electrical circuit battery models (thermal and electro-thermal) are able to offer relatively good performance with relatively low computational efforts and may be executed on-line (e.g. in the electric vehicle Battery Management System). The Electrothermal Impedance Spectroscopy (ETIS) can be used as a relatively simple and fast method for non-destructive parametrization of the battery thermal models. However, the ETIS requires expensive galvanostat with high-bandwidth and high-current capability for large format battery cells. Thus, this paper evaluates the possibility and accuracy of performing ETIS measurements with a standard battery test station (or bidirectional power supply) with low-bandwidth.

Wind power plant operators are often faced with extra charges when their power production does not match the forecasted power. Because the accuracy of wind power forecasts is limited, the use of energy storage systems is an attractive alternative even when large-scale aggregation of wind power is considered. In this paper, the economic feasibility of lithium-ion batteries for balancing the wind power forecast error is analysed. In order to perform a reliable assessment, an ageing model of lithium-ion battery was developed considering both cycling and calendar life. The economic analysis considers two different energy management strategies for the storage systems and it is performed for the Danish market. Analyses have shown that the price of the Li-ion BESS needs to decrease by 6.7 times in order to obtain a positive net present value considering the present prices on the Danish energy market. Moreover, it was found that for total elimination of the wind power forecast error, it is required to have a 25-MWh Li-ion battery energy storage system for the considered 2 MW WT.

This paper studies the impedance characteristics of a fresh 13 Ah high-power lithium titanate oxide (LTO) battery cell and analyses its dependence on the temperature and state-of-charge. The impedance of the battery cell was measured by means of the electrochemical impedance spectroscopy (EIS) technique for the entire state-of-charge (SOC) interval and considering five temperatures between 5oC and 45oC. By analyzing the measured impedance spectra of the LTO-based battery cell, it was found out that the cell’s impedance is extremely dependent on the operating conditions. By further processing the measurements data by means of curve fitting, it was found that the parameters of the equivalent electrical circuit (and the corresponding electro-chemical processes) are following different dependencies on the SOC, which in most of the cases are only slightly changing with the measurement temperature.

Lithium-Sulfur (Li-S) batteries are a promising energy storage technology, which draws interest due to their high theoretical limits in terms of specific capacity, specific energy and energy density. However as a drawback, they suffer from a high self-discharge rate, which is mainly caused by ongoing polysulfide shuttle. In this paper, the self-discharge behavior of Li-S batteries is experimentally investigated, considering various conditions as depth-of-discharge, temperature and idling time. The self-discharge rate under different conditions is identified and quantified. Moreover, a methodology for estimating the capacity of the high voltage plateau based on a self-discharge constant was analyzed; however, the method needs further improvements in order to estimate this capacity accurately for all conditions.

Lithium ion batteries with iron phosphate cathodes are gradually improving in their performance and gaining importance, and are more and more considered for new applications. Different aspects of this chemistry were studied in numerous publications; however, very little research was devoted to detailed empirical investigations in order to find out how self-discharge of this chemistry depends on different storing conditions. Precise knowledge about the level of the self-discharge of lithium ion battery cells is very important for improving the performance of the battery management system since it allows also for more precise determination of the actual battery SOC after prolonged storage. In this paper the self-discharge of the nanophosphate LiFePO4/C is studied at different temperature, SOC conditions and at different SOH levels of the battery. Moreover, cell to cell differences in self-discharge caused by the manufacturing tolerances are investigated.