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To meet the expected performance requirements of lithium‐ion batteries (LIBs), novel electrode materials, coatings and electrolytes have been studied in terms of their degradation mechanisms. Nevertheless, most of the methods used to track these mechanisms are not in operando, i. e., they do not follow them upon the practical LIB cell operation. The differential voltage analysis (DVA) and the incremental capacity analysis (ICA) constitute in operando techniques that can greatly help in monitoring batteries degradation mechanisms. We report here an in house developed software that allows the visualization of the DVA and the ICA curves of tested cells, with the possibility of rebuilding an experimental full‐cell capacity vs. potential curve through fitting of its electrodes' half‐cell capacity vs. potential curves. Those features can be applied to multiple charge‐discharge cycles without data pretreatment, offering data exportation. We illustrate the functionalities of our software and indicate perspectives for its further development. [ABSTRACT FROM AUTHOR]

Lithium-ion capacitors (LICs) are an optimal candidate to bridge the gap between lithium-ion battery and conventional supercapacitors as the promising electrochemical energy storage devices with fast charging-discharging capability and long cycle life. A three-electrode LIC pouch cell is fabricated employing an electrochemically driven lithium pre-doping method. Active materials of cathode and anode of LIC cells are activated carbon and pre-lithiated carbon, respectively. The electrochemical performances and capacity fading behaviors of LICs in an operating potential range of 2.2–3.8 V have been analyzed. The most direct influencing factor to LIC cycle performance is pointed at the developed capacity originated from the effective application of cathode material during the charge storage process. It was deeply discovered that the determined key to properties in a LIC system refers to the type of anode material and anode potential swing. Capacity fading of LICs upon cycling is proposed to be caused by the lapse of lithium stored in anode by dV/dQ analysis and an increase of internal resistance mainly emphasized on the structure difference through EIS characterization. As the energy density is increased to reach 63.05 Wh kg−1 based on the weight of both cathode and anode active materials and concurrently the initial capacitance is retained up to 96.33% after 5000 cycles at 8 C, HC as an anode material shows the prominent electrochemical performance. [ABSTRACT FROM AUTHOR]

The usage of electric vehicle batteries to assist the main electric grid for the storage of energy provided by intermittent sources should become an essential tool to increase the penetration of green energies. However, this service induces additional usage on the cells and, therefore, could degrade them further. Since degradation is path-dependent, it is of paramount importance to test the impact of all the different grid applications on the batteries. In this work, we tested the additional usage induced by using electric vehicle batteries for frequency regulation at moderate rates during rest or charge and found no detrimental effect after around 2000 cycles on the cells.

This paper presents results from a field test performed on commercial power-optimized lithium-ion battery cells cycled on three heavy-duty trucks. The goal with this study was to age battery cells in a hybrid electric vehicle (HEV) environment and find suitable methods for identifying cell ageing. The battery cells were cycled on in-house developed equipment intended for testing on conventional vehicles by emulating an HEV environment. A hybrid strategy that allows battery usage to vary within certain limits depending on driving patterns was used. This concept allows unobtrusive and low-cost testing of battery cells under realistic conditions. Each truck was equipped with one cell cycling equipment and two battery cells. One cell per vehicle was cycled during the test period while a reference cell on each vehicle experienced the same environmental conditions without being cycled. Differential voltage analysis and electrochemical impedance spectroscopy were used to identify ageing of the tested battery cells. Analysis of driving patterns and battery usage was performed from collected vehicle data and battery cell data.

This paper presents results from a field test performed on commercial power-optimized lithium-ion battery cells cycled on three heavy-duty trucks. The goal with this study was to age battery cells in a hybrid electric vehicle (HEV) environment and find suitable methods for identifying cell ageing. The battery cells were cycled on in-house developed equipment intended for testing on conventional vehicles by emulating an HEV environment. A hybrid strategy that allows battery usage to vary within certain limits depending on driving patterns was used. This concept allows unobtrusive and low-cost testing of battery cells under realistic conditions. Each truck was equipped with one cell cycling equipment and two battery cells. One cell per vehicle was cycled during the test period while a reference cell on each vehicle experienced the same environmental conditions without being cycled. Differential voltage analysis and electrochemical impedance spectroscopy were used to identify ageing of the tested battery cells. Analysis of driving patterns and battery usage was performed from collected vehicle data and battery cell data. [ABSTRACT FROM AUTHOR]

The usage of electric vehicle batteries to assist the main electric grid for the storage of energy provided by intermittent sources should become an essential tool to increase the penetration of green energies. However, this service induces additional usage on the cells and, therefore, could degrade them further. Since degradation is path-dependent, it is of paramount importance to test the impact of all the different grid applications on the batteries. In this work, we tested the additional usage induced by using electric vehicle batteries for frequency regulation at moderate rates during rest or charge and found no detrimental effect after around 2000 cycles on the cells. [ABSTRACT FROM AUTHOR]