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Accurate state of health (SOH) estimation of rechargeable batteries is important for the safe and reliable operation of electric vehicles (EVs), smart phones, and other battery operated systems. We propose a novel method for accurate SOH estimation which does not necessarily need full charging data. Using only partial charging data during normal usage, 10 derived voltage values ( v s e i ) are collected. The initial v s e i point is fixed and then for every 1.5% increase in the Coulomb counting, other points are selected. The difference between the v s e i values (Δ v s e i ) and the average temperature during the charging form the feature vector at different SOH levels. The training data set is prepared by extrapolating the charging voltage curves for the complete SOH range using initial 400 cycles of data. The trained artificial neural network (ANN) based on the feature vector and SOH values can be used in any battery management system (BMS) with a time complexity of only O (n 4) . Less than 1% mean absolute error (MAE) for the test cases has been achieved. The proposed method has a moderate training data requirement and does not need any knowledge of previous SOH, state of charge (SOC) vs. OCV relationship, and absolute SOC value. [ABSTRACT FROM AUTHOR]

The overall performance of battery packs may be affected by imbalances between the series connected cells which is more likely in packs with high number of cells needed to provide a high voltage as needed for example in electric vehicles. In this case, the overall capacity and power capability of the pack are limited by the weakest cell in the stack which results in incomplete utilisation of the pack's capabilities. In traditional centralised battery systems (TCBS), this is addressed by implementing cell active/passive balancing circuitry/techniques which restore some of the pack's energy capability. This paper proposes the use of cascaded modular battery systems (CMBS) to remove the need for extra balancing circuitry and maximises the performance and reliability of a battery system containing unequal matched/aged cells. The analysis is assessing the CMBS overall system efficiency, reliability and weight compared to the TCBS for a design of a 300 V/3.6 kW battery system as a case study. [ABSTRACT FROM AUTHOR]

The ultrahigh theoretical specific capacity and energy density of lithium‐sulfur batteries have attracted extensive research, but the main issues including the insulating nature of sulfur, large volumetric expansion during discharging, and shuttle effect of polysulfides still need to be solved. Herein, a hierarchical high‐porosity graphene oxide‐porous carbon/sulfur (GO‐PC/S) composite cathode is designed and fabricated. In this work, sodium chloride was used as temporary space holders to create a hierarchical porous structure for accelerating the transmission of Li+, accommodating the volumetric expansion, and enlarging the specific surface area (342.623 m2 g−1) up to eight times. Owing to the abundant oxygen‐containing functional groups of GO, sulfur and polysulfides can be effectively immobilized and the conductivity is enhanced by porous carbon. The Li−S battery exhibits outstanding kinetic performance and rate capability (618.3 mAh g−1 at 2 C) as well as excellent cycling performance over 300 cycles. [ABSTRACT FROM AUTHOR]

Highlights • The main focus is accelerated testing and degradation modeling of Li-ion batteries. • Discharge C-rate variable has been investigated for accelerating the battery testing. • The model is inspired by the physics of SEI layer formation. • The model utilizes historical degradation data for better generalization capability. • The non-linear mixed effect regression technique has been used to capture the battery-to-battery variations. Abstract As Li-ion batteries are used in increasingly diverse applications, their performance and reliability become more critical. Reliability testing of Li-ion batteries involves battery capacity fade monitoring over repeated charging/discharging cycles. Cycling at a nominal charge/discharge current requires an extensive amount of time and resources, and hence a battery qualification process based on battery cycle testing may cause delays in time to market. Discharge C-rate variable can be used for accelerating Li-ion battery cycle testing. This paper develops an accelerated capacity fade model for Li-ion batteries under multiple C-rate loading conditions, to translate the performance and degradation of a battery population at accelerated C-rate conditions to normal C-rate conditions. A nonlinear mixed-effects regression modeling technique is used to take into account the variability of repeated capacity measurements on individual batteries in a population. The model is validated using the experimental data from two battery populations that have been fielded. [ABSTRACT FROM AUTHOR]

Abstract Alkali-metal ions storage in carbon materials is of great interests for developing high-performance anodes for batteries. While Li, Na ions storage has been extensively investigated, systematic studies on the correlation between K ions storage and carbon microstructure have rarely been conducted. The large radius of K ions leaves a legitimate question whether the charge storage sites for Li and Na ions are also active for K ions. Herein, electrospun carbon nanofibers are employed as model materials to explore the K-ion storage behaviors in carbon with representative microstructures. By combining in-situ characterization and theoretical calculations, three active sites have been unveiled, including (i) uptake of K-ion by defect sites; (ii) K ions adsorption on isolated graphene sheets in partially disordered carbon; (iii) K ions intercalation between graphene layers for carbon with a high degree of graphitization. A similar reversible capacity around 280 mAh/g is obtained for various carbon structures while their voltage profiles are highly disparate. Remarkably, it is found that non-graphitic carbon presents better rate capability and less temperature-dependence due to the faster ion diffusion. These findings offer new insights into the design of advanced carbon anode materials with tunable properties for K-ion batteries. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract Sodium-ion batteries (SIBs) have recently drawn great interest as an alternative due to their lower cost compare to lithium-ion batteries (LIBs). As in the practical application in LIBs manufacturing, Cu and Al foils are generally used as the current collectors for the anode and cathode of SIBs respectively. The concern for amorphous Li-Al alloy formation at ∼0.2 V is the main reason for selecting a different metallic (i.e. Cu) current collector. However, it is not the case for the SIBs since Na-Al alloys are formed at much lower potentials. In this paper, we demonstrate that the electrochemistry of SIBs allows an Al current collector to be used for the SIB anode without any adverse effect. The cell performance using a high capacity Sb 2 S 3 -reduced graphene oxide (Sb 2 S 3 -rGO) composite anode is undistinguishable between the use of Cu and Al current collectors. The reversible storage of Na+ in this Sb 2 S 3 -rGO composite is evaluated on both Cu-foil and Al-foil current collectors and comparable results are obtained: high desodiation specific capacities of ∼555 mAh g−1 (on Al-foil current collector) and 537 mAh g−1 (on Cu-foil current collector) for 70 cycles at 100 mA g−1. Therefore, the Al current collector can replace Cu in SIBs, which simplifies the construction of SIB cells and reduces the material cost in SIB production. Graphical abstract Image 1 Highlights • The Al current collector is used in anode for the electrochemistry of NIBs. • The effect of Al and Cu current collectors is compared on Sb 2 S 3 -rGO composite anode. • The capacity of ∼555 mAh g−1 on Al-foil for 70 cycles is obtained in Sb 2 S 3 -rGO anode. • 537 mAh g−1 on Cu-foil for 70 cycles at 100 mA g−1 is obtained in Sb 2 S 3 -rGO anode. [ABSTRACT FROM AUTHOR]

Capacity degrading over repeated charge/discharge cycles is a main parameter for evaluating battery performance, which is commonly used for determining the state of health. However, it is difficult to measure the available capacity because it requires the normal operation to be terminated and a long time-consuming detection process. This study presents an online available-capacity estimation method by combining extended Kalman filter (EKF) with Gaussian process regression (GPR) for the daily partial charge data of lithium-ion batteries. First, GPR is used to establish an empirical model of the time-voltage curve in the constant current charge cases. Second, by analyzing the characteristics of the charge curve, the daily piecewise partially charge data are registered with the piecewise complete charge data to update GPR model and preestimate the equivalent complete charge time. On this basis, the equivalent complete charge time is refined by EKF. Furthermore, the available capacity estimation of the battery with constant current charge processes under different aging conditions is achieved. It is verified by experiments that the estimated error can be controlled within 5% when the actual available capacity is greater than 90% of the initial capacity. [ABSTRACT FROM AUTHOR]

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One-dimensional nanostructures comprising MoSe 2 nanosheets and carbon with uniformly distributed nanovoids are prepared through the application of a simple selenization treatment to electrospun nanofibers. Size-controlled polystyrene nanobeads in the form of an aqueous suspension are introduced for the first time as an electrospinning solution, which enables the precise control of void size and uniform distribution of nanovoids in the one-dimensional (1D) nanostructure. The discharge capacity and Coulombic efficiency of the porous MoSe 2 /C composite nanofibers after the 200th cycle at a current density of 0.2 A g −1 are 454 mA h g −1 and 98.4%, implying efficient Na + ion insertion and extraction in the composites. In addition, a high discharge capacity of 280 mA h g −1 at a current density of 7.0 A g −1 demonstrates an excellent rate capability and fast Na + ion and electron transfer. Few-layered MoSe 2 and highly conductive carbon facilitate ion and electron diffusion during cycling. Uniformly distributed nanovoids in the structure can accommodate the volume expansion induced by electrochemical reaction of Na + ions with the composites and allow efficient penetration of electrolyte into electrodes. [ABSTRACT FROM AUTHOR]

Abstract Lithium-sulfur (Li-S) batteries exhibit great potential for next-generation high energy density energy storage. However, the insulativity of sulfur and the "shuttle effect" of polysulfides result in low utilization efficiency of active sulfur, fast capacity decay and inferior cycling stability, which pose the key challenge to their practical applications. Herein, a N, I-dual-doped hierarchical porous activated carbon (NIWFC) is successfully prepared for advanced Li-S batteries by the simple one-pot pyrolysis and hydrothermal processes. The obtained NIWFC owns interconnected porous framework with desirable specific surface area (2088.56 m2 g−1) and large volume space (1.106 cm3 g−1), which can accommodate high content of active sulfur and immobilize polysulfides through physical confinement. Moreover, the existence of N and I heteroatoms could effectively strengthen the chemical adsorption to polysulfides and create more active sites to enhance sulfur utilization. Attributed to these merits, impregnating sulfur into NIWFC (NIWFC/S) as cathode of Li-S batteries achieves a high initial discharge capacity of 1284.1 mAh g−1 at 0.1 C (remaining at 916.7 mAh g−1 after 100 cycles) and the outstanding cycling stability with a low capacity fading rate of 0.061% per cycle over 350 cycles at 1.0 C. This work provides a facile and cost-effective strategy to design a novel sustainable N, I-dual-doped porous carbon for high performance Li-S batteries and various energy storage fields. Graphical abstract A novel sustainable N, I-dual-doped hierarchical porous activated carbon (NIWFC) is rationally designed and successfully fabricated by the facile pyrolysis and hydrothermal processes for the advanced lithium-sulfur (Li-S) batteries. Image 1 Highlights • A novel N, I-dual-doped porous carbon is designed and successfully fabricated. • The porous NIWFC material displays the strong adsorbability for polysulfides. • The as-prepared NIWFC/S cathode exhibits remarkable electrochemical performance. [ABSTRACT FROM AUTHOR]

Abstract: Disordered carbons have captured extensive interest as anode materials for Na‐ion batteries (NIBs) due to the abundant resources, competitive specific capacity, and low cost. Here, a facile strategy of pre‐oxidation is successfully adopted to tune the microstructure of carbon anode to facilitate sodium storage. Pitch is selected as the low‐cost and high carbon yield precursor. An easy pre‐oxidation treatment in air can enable pitch to realize an effective structural conversion from ordered to disordered at further carbonization processes. Compared with the carbonized pristine pitch, the carbonized pre‐oxidation pitch increases the carbon yield from 54 to 67%, the sodium storage capacity from 94.0 to 300.6 mAh g−1, and the initial Coulombic efficiency from 64.2 to 88.6%. Experiment results reveal that the introduction of oxygen based functional groups is the key to achieve the highly disordered structure, not only ensuring the cross‐linkage during low‐temperature pre‐oxidation process but also suppressing the carbon structure from melting and rearranging in the high‐temperature carbonization process. Most importantly, this facile pre‐oxidation strategy can also be extended to other carbon precursors to facilitate the low‐cost and high‐performance disordered carbon anodes for NIBs and beyond. [ABSTRACT FROM AUTHOR]

We develop a novel approach to improve the robustness of the interface between the hydrocarbon (HC) membrane and the perfluorosulfonic acid (PFSA) ionomer-based catalyst layer (CL) in membrane electrode assemblies (MEAs). This approach involves the creation of a gradient-composition interfacial bonding layer, in which the HC and PFSA contents are gradually varied along the thickness direction. The layer is fabricated using a simple spray-coating method, in which HC and PFSA ionomer mixtures with different compositions are sprayed stepwise onto both sides of the HC membrane surface. The interfacial structure developed in this process minimizes the chemical incompatibility between the HC and PFSA polymers. Owing to the tightly bound sublayers resulting from the intertwined HC and PFSA microdomains, the gradient-composition bonding layer provides a significantly improved interfacial adhesion strength (14 times higher than that of the pristine membrane without bonding layer) between the HC membrane and the PFSA-based CL. Finally, the fabricated MEA exhibits a >433% higher durability in humidity cycling tests compared with the pristine MEA without interfacial bonding layer, together with a better retention of its initial performance. [ABSTRACT FROM AUTHOR]

In the realm of next generation cathode materials for Li-ion rechargeable batteries, Li and Mn riched (LMR) cathodes are important candidate because of its high nominal voltages and specific discharge capacities. However, capacity and voltage fade in LMR cathodes are attributed to the formation of spinel like phase with repeated cycling. In the present work, LMR cathode of composition 0.5Li2MnO3-0.5LiMn0.375Ni0.375Co0.25O2 (layered notation Li1.2Mn0.55Ni0.15Co0.1O2) and its potassium doped variants are investigated in terms of their structural and electrochemical behavior. The cycleability, rate capability and voltage fade characteristics of potassium doped cathodes are found to be improved as compared to the undoped cathode. Thus, Li1.184K0.016Mn0.55Ni0.15Co0.1O2LMR cathode yields a capacity retention ~86% after 50 charge-discharge cycles. Using X-ray diffraction and Raman spectroscopy analyses in conjunction with impedance spectroscopy, X-ray photoelectron spectroscopy, and galvanostatic intermittent titration technique we have established that cycling induced layered to spinel phase transition is retarded in K doped LMR cathodes to yield improved electrochemical performance and voltage fade characteristics. [ABSTRACT FROM AUTHOR]

A hybrid Zn battery is developed by integrating a Zn-Co 3 O 4 battery and a Zn-air battery at the cell level, which combines the unique advantages of a high working voltage and a high discharge capacity. However, the design of the working electrode, which is the key to the battery performance, is absent in the literature. In this work, the electrode design of hybrid Zn-Co 3 O 4 /air batteries for performance improvements is investigated by considering the active material loading and the surface hydrophobicity of the Co 3 O 4 nanosheet-decorated carbon cloth electrode. The results demonstrate that the capacity of the Zn-Co 3 O 4 battery first dramatically increases with the loading, but the improvement becomes limited when the loading further increases. The discharge voltage plateau of the Zn-air battery increases first and then keeps decreasing. The reason is that although both the active material and the surface area increase, the increased dimension of nanosheets increases the transport resistance, especially for electrons and oxygen. For a given electrode, the discharge voltage of the Zn-air battery first increases with an increase of the hydrophobicity due to the creation of gaseous oxygen transport pathway, but then decreases due to the coverage of active sites. While both the voltage and the capacity of the Zn-Co 3 O 4 battery decrease with the hydrophobicity, which is attributed to the decreased contact surfaces between the reactant and the liquid electrolyte. Based on the optimized active material loading and surface hydrophobicity, a hybrid Co 3 O 4 /air battery delivers a high energy density of 936 Wh kg −1 (on the weights of Co 3 O 4 and consumed Zn) and stable discharge and charge voltages ranging from 0.94 V to 2.01 V for 400 cycles. This work illustrates that for high-performance hybrid batteries, the active material loading of the electrode should be well designed considering the transport of electrons and oxygen, and a balance between the hydrophobicity and hydrophilicity should be established. [ABSTRACT FROM AUTHOR]

The accuracy for positional alignment of the positive electrode vs. the negative electrode is of great importance for the quality of assembly of lithium ion cells. Area-oversized negative electrodes increase the tolerance for electrode alignment. In this study, the impact of area-oversizing of the negative electrode on the specific capacity losses during charge/discharge cycling is systematically investigated by using electrochemical and analytical methodologies. It is shown, that with a higher degree of area-oversizing more active lithium is kinetically trapped in the outer negative electrode areas (“overhang”), causing performance-deteriorating losses in usable specific capacity. Nevertheless, most of this “lost” specific capacity is of reversible nature as the trapped active lithium can be electrochemically recovered, which is analytically proven by inductively coupled plasma-optical emission spectrometry (ICP-OES) and laser ablation-inductive coupled plasma-mass spectrometry (LA-ICP-MS). Given this relation, a periodic application of a short constant voltage step after discharge results in a significant performance increase. In contrast, holding the cell in the charged state is detrimental for cells with area oversized negative electrodes as the amount of reversible and irreversible trapped active lithium increases. Based on the obtained insights, the influence of variations of the electrochemical conditions on charge/discharge cycling performance is discussed. [ABSTRACT FROM AUTHOR]

Nanostructures always have an advantage in electrochemical research. In this work, the GeNb 18 O 47 nanowires are synthesized by an easy electrospinning method for the first time. We study morphologies and electrochemical properties of as-obtained GeNb 18 O 47 nanowires via the X-ray diffraction, charge/discharge curve, cyclic voltammetry, scanning electron microscopy and transmission electron microscopy. As expected, GeNb 18 O 47 nanowires exhibit impressive charge capacity of 216.9 mAh g −1 at a current density of 100 mA g −1 and high-capacity retention of 93.6% after 200 cycles. Electrochemical analyses show that GeNb 18 O 47 nanowires exhibit the lower redox polarization, smaller charge transfer resistance and higher Li + diffusion coefficient compared with sol-gel formed bulk sample. Therefore, the GeNb 18 O 47 nanowire is a promising active electrode material for the lithium batteries. [ABSTRACT FROM AUTHOR]

We report a new carbonate electrolyte of 1 M LiFSI dissolved in the EMC/FEC (70/30, v/v) solvent for lithium metal based batteries. Favorable LiF-rich SEI layer is formed on Li anode to suppress side reactions under the synergistic effect of LiFSI and FEC. Thus, the dendrite-free Li morphology and high Coulombic efficiency for Li plating/stripping can be obtained with improved cycle stability compared with conventional LiPF 6 /EC-DMC electrolyte. Li | S@pPAN cell assembled with the new electrolyte shows quite low lithium ion transfer resistance, excellent long cycle stability and rate performance. A high discharge capacity of 1270 mAh g −1 remains after 1000 cycles at 2 C, with an inappreciable capacity decay of 0.0015% per cycle. Due to the low interface impedance and high Li + diffusion coefficient, a capacity of 1210 mAh g −1 even at 10 C can be maintained. This deliberately designed electrolyte offers new insights into the understanding of interfacial stability between electrolyte and Li anode. Furthermore, our work offers a new approach towards high energy-density and high rate Li-S battery. [ABSTRACT FROM AUTHOR]

A self-charged photo-power cell, named as light sensitive energy storage device has been developed in a simplified way for application as a portable photo-charged power bank. The Photo-Power Cell is fabricated by assembling a photoelectrode (FTO) involving a dye-sensitized solar part as photo-electrons generator, combined with the electroactive and high dielectric SrF 2 -PVDFNCfilm as storage unit. Electroactive β phase crystallization and large interfacial polarization between the SrF 2 NPs and poly (vinylidene fluoride) matrix result in high dielectric value ∼ 5141 of the nanocomposite film. The device is charged by up to 1.48 V under visible light illumination (∼110 mW/cm 2 ) with a constant discharge current density ∼1.64 mA/cm 2 . The photogenerated charge and power density of the photo-power cell are found to be ∼24.3 W/m 2 and 2400 C/m 2 respectively. Our photo-power cell shows maximum areal specific capacitance ∼1600 F/m 2 with 92% energy storage efficiency. The achieved overall efficiency (%) is found ∼ 2.57. The charging-discharging stability is also tested for a long time span of 12 weeks. The efficacy and durability of our fabricated device has also been demonstrated by glowing up 24 commercially available blue light emitting diodes for 10 days with same intensity by charging one time under light. [ABSTRACT FROM AUTHOR]

In this paper, a series of sulfonated poly(ether ether ketone) (SPEEK) hybrid membrane doped by the different amount of sulfonated graphene oxide (SGO) nanosheets are prepared by solution-casting method. The membrane structure, physicochemical property and cell performance of vanadium redox flow battery (VRB) have been characterized through FT-IR, SEM, XPS, and single-cell test system, etc . The incorporation of SGO in SPEEK improves the water uptake, ion exchange capacity and proton conductivity of the hybrid membrane, and effectively reduces the swelling degree and the vanadium ion permeability. In the single cell performance test, the energy efficiency of the SPEEK/SGO-3 hybrid membrane is 81.1%, which is higher than that of SPEEK (76.0%) and Nafion 117 membrane (73.8%). And, a longer self-discharge time (56.6 h) against Nafion 117 (23.5 h) and SPEEK (32.8 h) membrane is shown. In addition, the incorporated SGO nanofillers don't improve the chemical stability of SPEEK membrane soaked by 1.5 M V 5+ solution although they block the vanadium ion permeation. Then, the durability for SPEEK/SGO hybrid membranes should be further explored for VRB system. [ABSTRACT FROM AUTHOR]

We have developed a new binder-free hybrid anode material for lithium-ion batteries, by directly coating spinel Li 4 Ti 5 O 12 particles using in-situ polymerization of styrenesulfonate (SS) to form a core-shell structure. The resulting hybrid anode has significantly improved electrochemical performance, with higher reversible capacity, rate-capability, and capacity value compared with pure Li 4 Ti 5 O 12 . Of the initial discharge capacity of 239.2 mAh g −1 , 95.6% was retained after 100 cycles at 0.1 C-rate. The high cycle performance with increased discharge capacity is attributed to the coated poly (styrenesulfonate) (PSS) shell, which takes part in lithium ion storage and prevents the growth of a solid electrolyte interface (SEI) layer. The fast electron transfer in PSS also allows high rate-capability. Moreover, we clarify the contribution of carbon conductor in the range of 0.01 V–1.0 V. [ABSTRACT FROM AUTHOR]

The overcharge safety and behaviors of lithium-ion batteries (LIBs) with LiCoO 2 cathode are investigated under a successive constant current (CC) and constant voltage (CV) charge mode. It is indicated that in the case of smaller charge currents, a higher probability for the LIBs passing the overcharging test can be obtained. The batteries can safely pass CC overcharge test at 0.25C to 10 V, and then about 80% batteries can also pass CV overcharge test. Whereas, with increasing the CC currents to 0.33C, 0.5C, and 1C, about 50%, 30%, and 10% batteries can directly pass the overcharge test at the CC step, and then about 20%, 10%, and 0% batteries approach 10 V and subsequent pass CV overcharge test, respectively. Besides the charge current, it is also demonstrated that whether the LiCoO 2 /graphite batteries are likely to achieve energy balance and pass the overcharge test basically depends on the formation of the internal short-circuit pathways derived from the cobalt and lithium deposition in the separator during the overcharge process. The cobalt deposition will be more uniform when the battery core has shape stability of assembly-structure, which can be used as an effective measure to raise LIBs through the overcharge test. In addition, relative more uniform cobalt dendrites can also be formed if a double layer separator is adopted, which reduces the local short-circuit risk caused by the melting or shrinkage of the separator and correspondingly improves the ratio of LIBs passing through the overcharge test. These risk reduction measures can be used in the battery manufacture to improve the overcharge safety of LIBs. [ABSTRACT FROM AUTHOR]

Soft carbons with high conductivity have potential advantages as high-performance sodium-ion battery anodes, however, they suffer from small interlayer distance and low hereoatom content. In this work, porous carbon nanosheets (PCNS1000) with tunable microstructure, pore structure and chemical composition were prepared from coal tar pitch through a two-step process involving NaCl template method and NH 3 treatment. PCNS1000 possesses an expanded interlayer distance of 3.82 Å, mesopore structure with average pore size of 5.7 nm, and a high nitrogen content of 4.17 wt%. Moreover, PCNS1000 retains soft carbon feature to a certain extent and consequent relative high conductivity. Benefiting from its appropriate structure and chemical composition, PCNS1000 exhibits a high reversible capacity of 270 mAh g −1 at 100 mA g −1 in sodium-ion half cells and excellent rate capability of 124 mAh g −1 at large current of 10 A g −1 . After an ultralong charge-discharge cycling of 10,000 times, a high capacity retention of 86% was achieved, indicating its excellent electrochemical stability. The full cell assembled by Na 3 V 2 (PO 4 ) 3 cathode and PCNS1000 anode delivers a high capacity of 265 mAh g −1 at 100 mA g −1 , with a good cycling ability of 89% capacity retention after 100 cycles at 1.0 A g −1 . [ABSTRACT FROM AUTHOR]

Featured Application: In the long term, results presented with this paper suggest to carry out in a systematic manner, the evaluation of batteries performances at the cycling temperature. According to this, in real applications as in automotive, it can be recommended to use the track of the temperature within the battery pack (e.g., mean) recorded by the battery management system, to define the temperature at which battery cells performances should be evaluated. In addition, room temperature can be used if needed for the comparison of battery cells performances, of same type that are though not operating at the same temperature. This paper presents the results regarding the thermal characterisation and modelling of high energy lithium-ion battery cells at both room (25 °C) and cycling (35 °C) temperatures. In this work two types of Nickel Manganese Cobalt (NMC) batteries are studied: a fresh (or uncycled) and an aged (or cycled) battery cells. The ageing of the studied NMC battery cells is achieved by means of accelerated ageing tests (i.e., repetition of numerous charge and discharge cycles) at 35 °C cycling temperature. Temperature at the surface of the battery cells is characterised, with a set of three discharge current rates 0.3C (i.e., 6 A), 1C (i.e., 20 A) and 2C (i.e., 40 A), and the evolutions at three different locations on the surface of the battery cells namely, at the top, in the center and at the bottom regions are measured. In addition, temperature and ageing dependent electrochemical-thermal modelling of the uncycled and cycled battery cells is also successfully accomplished in case of both room and cycling temperatures. Numerical simulations were carried out in case of high 2C constant current rate, and the assessment of the modelling accuracy by comparison of the predicted battery cells voltage and temperature with respect to the experimental data is further presented. With this paper, thermal performances of battery cells prior and after long-term cycling are evaluated at the cycling temperature, next to the ambient temperature. Hence, thermal characterisation and modelling results are more closely reflecting that encountered by the battery cells in real cycling conditions, so that their performances are believed in this way to be more objectively evaluated. [ABSTRACT FROM AUTHOR]

Energy storage devices, which can combine the advantages of lithium-ion battery with that of electric double layer capacitor, are of prime interest. Recently, composite cathodes, which combine a battery material with capacitor material, have shown promise in enhancing life cycle and energy/power performances. Lithium-ion capacitor (LIC), with unique charge storage mechanism of combining a pre-lithiated battery anode with a capacitor cathode, is one such device which has the potential to synergistically incorporate the composite cathode to enhance capacity and cycle life. We report here a hybrid LIC consisting of a lithium iron phosphate (LiFePO 4 -LFP)/Activated Carbon composite cathode in combination with a hard carbon anode, by integrating the cycle life and capacity enhancing strategies of a dry method of electrode fabrication, anode pre-lithiation and a 3:1 anode to cathode capacity ratio, demonstrating a long cycle life, while elaborating on the charge sharing between the faradaic and non-faradaic mechanism in the battery and capacitor materials, respectively in the composite cathode. An excellent cell capacity retention of 94% (1000 cycles at 1C) and 92% (100,000 cycles at 60C) were demonstrated, while retaining 78% (over 6000 cycles at 2.7C) and 67% (over 70,000 cycles at 43C) of the LFP capacity in the composite cathode. [ABSTRACT FROM AUTHOR]

Recently, we have reported a new all tungsto-cobalt heteropoly acid redox flow battery (all H 6 [CoW 12 O 40 ] RFB) with high coulombic efficiency. Because of the relatively large ion size and high negative charge, the tungsto-cobalt heteropoly acid anion is difficult to cross Nafion membrane, which makes it possible to employ thinner Nafion membrane in all H 6 [CoW 12 O 40 ] RFB. In this study, three types of Nafion membranes with different thickness, namely, N212 (50 μm), N211 (25 μm), and N-17 (home-made, 17 μm) are used as polymer electrolyte to investigate its effects on the performance of all H 6 [CoW 12 O 40 ] RFB. The ion permeability increases while the area specific resistanceas decreases as reducing the membrane thickness. As a result, the RFB with N211 membrane exhibits best comprehensive performance, which exhibites the energy efficiency of 88.6% at current density of 0.10 A cm −2 and the power density of 0.56 W cm −2  at 0.60 A cm −2 . Moreover, the battery delivers impressive cycling performance of 100 cycles with an average coulombic efficiency of 99.4%, energy efficiency of 80.0%, and capacity retention of 99.98% per cycle at current density of 0.20 A cm −2 . [ABSTRACT FROM AUTHOR]

Abstract: Rechargeable Li−O2 batteries represent a highly attractive battery technology, owing to a high theoretical energy density of 3500 Wh kg−1, but they suffer from large charging polarization and lithium anode degradation on cycling. Herein, we report a Li−O2 battery system with reduced polarization and a long lifespan, which is realized by using a novel Li@Super P composite anode integrated with lithium iodide in ether‐based electrolyte. Coating a Super P carbon layer, with an optimal thickness of approximately 30 μm, onto the lithium anode results in a lowered interface impedance and a decreased Li depositing/stripping overpotential (<15 mV) over 300 cycles at 0.3 mA cm−2. The Li−O2 batteries assembled with the Li@Super P anode and LiI additive could mitigate the detrimental shuttling effect of I3− and deliver a high reversible capacity of 1000 mAh g−1 with a median charge voltage lower than 3.3 V after 50 cycles. This study provides a simple yet effective way to protect the lithium anode and design high‐performance Li−O2 batteries. [ABSTRACT FROM AUTHOR]

Redox flow batteries (RFBs) are rugged systems, which can withstand several thousand cycles and last many years. However, they suffer from low energy density, low power density, and low efficiency. Integrating a Thermally Regenerative Electrochemical Cycle (TREC) into the RFB, it is possible to mitigate some of these drawbacks. The TREC takes advantage of the temperature dependence of the cell voltage to convert heat directly into electrical energy. Here, the performance increase of a TREC-RFB is investigated using two kinds of all-vanadium electrolyte chemistries: one containing a typical concentration of sulfuric acid and one containing a large excess of hydrochloric acid. The results show that the energy density of the system was increased by 1.3Wh L −1 and 0.8Wh L −1 , respectively and the overall energy efficiency also increased by 9 and 5 percentage points, respectively. The integration of the heat exchangers necessary to change the battery temperature is readily facilitated by the design of the redox flow battery, which already utilizes fluid circulation loops. [ABSTRACT FROM AUTHOR]

The long-term operation of the vanadium redox flow battery is accompanied by ion diffusion across the separator and side reactions, which can lead to electrolyte imbalance and capacity loss. The accurate online monitoring of capacity loss is therefore valuable for the reliable and efficient operation of vanadium redox flow battery system. In this paper, a model-based online monitoring method is proposed to detect capacity loss in the vanadium redox flow battery in real time. A first-order equivalent circuit model is built to capture the dynamics of the vanadium redox flow battery. The model parameters are online identified from the onboard measureable signals with the recursive least squares, in seeking to keep a high modeling accuracy and robustness under a wide range of working scenarios. Based on the online adapted model, an observer is designed with the extended Kalman Filter to keep tracking both the capacity and state of charge of the battery in real time. Experiments are conducted on a lab-scale battery system. Results suggest that the online adapted model is able to simulate the battery behavior with high accuracy. The capacity loss as well as the state of charge can be estimated accurately in a real-time manner. [ABSTRACT FROM AUTHOR]

The performance of lead-acid battery is improved in this work by inhibiting the corrosion of negative battery electrode (lead) and hydrogen gas evolution using ionic liquid (1-ethyl-3-methylimidazolium diethyl phosphate). The results display that the addition of ionic liquid to battery electrolyte (5.0 M H 2 SO 4 solution) suppresses the hydrogen gas evolution to very low rate 0.049 ml min −1 cm −2 at 80 ppm. Electrochemical studies show that the adsorption of ionic liquid molecules on the lead electrode surface leads to the increase in the charge transfer resistance and the decrease in the double layer capacitance. I also notice a noteworthy improvement of battery capacity from 45 mAh g −1 to 83 mAh g −1 in the presence of ionic liquid compound. Scanning electron microscopy and energy dispersive X-ray analysis confirm the adsorption of ionic liquid molecules on the battery electrode surface. [ABSTRACT FROM AUTHOR]

In an all-vanadium redox flow battery (VRFB), a shunt current is inevitable owing to the electrically conductive electrolyte that fills the flow channels and manifolds connecting cells. The shunt current decreases the performance of a VRFB stack as well as the energy conversion efficiency of a VRFB system. To understand the shunt-current loss in a VRFB stack with various designs and operating conditions, a mathematical model is developed to investigate the effects of the shunt current on battery performance. The model is calibrated with experimental data under the same operating conditions. The effects of the battery design, including the number of cells, state of charge (SOC), operating current, and equivalent resistance of the electrolytes in the flow channels and manifolds, on the shunt current are analyzed and discussed. The charge-transfer efficiency is calculated to investigate the effects of the battery design parameters on the shunt current. When the cell number is increased from 5 to 40, the charge transfer efficiency is decreased from 0.99 to a range between 0.76 and 0.88, depending on operating current density. The charge transfer efficiency can be maintained at higher than 0.9 by limiting the cell number to less than 20. [ABSTRACT FROM AUTHOR]

Abstract: Hybrid sodium‐based dual‐ion capacitors (NDICs), which integrate the advantages of supercapacitors and sodium‐ion batteries, have attracted tremendous attention recently. In this work, hybrid sodium‐based dual‐ion capacitors are successfully developed with nitrogen‐doped microporous hard carbon as the cathode and soft carbon as the anode. N‐doping is beneficial to the functional groups, porous structure, and electric conductivity of hard carbon. Hybrid NDICs possess a wide voltage range (0.01–4.7 V), high‐energy density of 245.7 W h kg−1 at a power density of 1626 W kg−1, long cycle life (1000 cycles), and outstanding rate performance. [ABSTRACT FROM AUTHOR]

Abstract: The intrinsic polysulfides shuttle, resulting from not only concentration‐gradient diffusion but also slow conversion kinetics of polysulfides, bears the primary responsibility for the poor capacity and cycle stability of lithium–sulfur batteries (LSBs). Here, it is first presented that enriched edge sites derived from vertical standing and ultrathin 2D layered metal selenides (2DLMS) can simultaneously achieve the thermodynamic and kinetic regulation for polysulfides diffusion, which is systematically elucidated through theoretical calculation, electrochemical characterization, and spectroscopic/microscopic analysis. When employed to fabricate compact coating layer of separator, an ultrahigh capacity of 1338.7 mA h g−1 is delivered after 100 cycles at 0.2 C, which is the best among the reports. Over 1000 cycles, the cell still maintains the capacity of 546.8 mA h g−1 at 0.5 C. Moreover, the cell exhibits outstanding capacities of 1106.2 and 865.7 mA h g−1 after 100 cycles at stern temperature of 0 and −25 °C. The superior low‐temperature performance is appealing for extended practical application of LSBs. Especially, in view of the economy, the 2DLMS is recycled as an anode of lithium‐ion and sodium‐ion batteries after finishing the test of LSBs. The low‐cost and scalable 2DLMS with enriched egde sites open a new avenue for the perfect regulation of the sulfur electrode. [ABSTRACT FROM AUTHOR]

Abstract: Sodium ion batteries (NIBs) have become attractive promising alternatives to lithium ion batteries in a broad field of future energy storage applications. The development of high‐performance anode materials has become an essential factor and a great challenge toward satisfying the requirements for NIBs, advancement. This work is the first report on GeS2 nanocomposites uniformly distributed on reduced graphene oxide (rGO) as promising anode materials for NIBs prepared via a facile hydrothermal synthesis and a unique carbo‐thermal annealing. The results show that the GeS2/rGO hybrid anode yields a high reversible specific capacity of 805 mA h g−1 beyond the theoretical capacity, an excellent rate capability of 616 mA h g−1 at 5 A g−1, and a cycle retention of 89.4% after 100 cycles. A combined ex situ characterization study reveals that the electrochemically driven amorphization plays a key role in achieving efficient sodium storage by accommodating excess sodium ions in the electrode materials. Understanding the sequential conversion‐alloying reaction mechanism for GeS2/rGO hybrid anodes provides a new approach for developing high‐performance energy storage applications. [ABSTRACT FROM AUTHOR]

Abstract: Despite the outstanding gravimetric performance of lithium–sulfur (Li–S) batteries, their practical volumetric energy density is normally lower than that of lithium‐ion batteries, mainly due to the low density of nanostructured sulfur as well as the porous carbon hosts. Here, a novel approach is developed to fabricate high‐density graphene bulk materials with “ink‐bottle‐like” mesopores by phosphoric acid (H3PO4) activation. These pores can effectively confine the polysulfides due to their unique structure with a wide body and narrow neck, which shows only a 0.05% capacity fade per cycle for 500 cycles (75% capacity retention) for accommodating polysulfides. With a density of 1.16 g cm−3, a hybrid cathode containing 54 wt% sulfur delivers a high volumetric capacity of 653 mA h cm−3. As a result, a device‐level volumetric energy density as high as 408 W h L−1 is achieved with a cathode thickness of 100 µm. This is a periodic yet practical advance to improve the volumetric performance of Li–S batteries from a device perspective. This work suggests a design principle for the real use Li–S batteries although there is a long way ahead to bridge the gap between Li–S batteries and Li–ion batteries in volumetric performance. [ABSTRACT FROM AUTHOR]

Abstract: Presently, commercialization of sodium‐ion batteries (SIBs) is still hindered by the relatively poor energy‐storage performance. In addition, low‐temperature (low‐T) Na storage is another principal concern for the wide application of SIBs. Unfortunately, the Na‐transfer kinetics is extremely sluggish at low‐T, as a result, there are few reports on low‐T SIBs. Here, an advanced low‐T sodium‐ion full battery (SIFB) assembled by an anode of 3D Se/graphene composite and a high‐voltage cathode (Na3V2(PO4)2O2F) is developed, exhibiting ultralong lifespan (over even 15 000 cycles, the capacity retention is still up to 86.3% at 1 A g−1), outstanding low‐T energy storage performance (e.g., all values of capacity retention are >75% after 1000 cycles at temperatures from 25 to −25 °C at 0.4 A g−1), and high‐energy/power properties. Such ultralong lifespan signifies that the developed sodium‐ion full battery can be used for longer than 60 years, if batteries charge/discharge once a day and 80% capacity retention is the standard of battery life. As a result, the present study not only promotes the practicability and commercialization of SIBs but also points out the new developing directions of next‐generation energy storage for wider range applications. [ABSTRACT FROM AUTHOR]

Li 4 Ti 5 O 12 microspheres (LTOS)/multiwalled carbon nanotubes (MWCNTs) composites with different contents of MWCNTs have been prepared by electrostatic self-assembly. In the preparation, the surface charge of cetyltrimethylammonium bromide (CTAB)-functionalized HNO 3 -treated MWCNTs (CTAB-functionalized MWCNTs) in aqueous solution is positive because of the hydrophobic force between MWCNTs and the long alkane chain of CTAB, while that of LTOS is negative. Therefore, electrostatic attraction occurs between LTOS and CTAB-functionalized MWCNTs when they approach, and LTOS/MWCNTs composites are obtained after removing CTAB by calcination. Notably, LTOS/MWCNTs composites with 10  wt. % MWCNTs exhibit superior rate performance and cyclic stability. Their specific capacities at 5C, 10C, 20C, 40C and 60C are 170, 168, 167, 165 and 160 mAh·g −1 , respectively. Even at 80C and 90C, the specific capacities are still as high as 154 and 152 mAh·g −1 . Moreover, the specific capacity retains 140 mAh g −1 after 2000 cycles at 10C. The excellent performance of LTOS/MWCNTs composites is mainly owing to the conductive network forming by MWCNTs connecting different LTOS, acting as highway for the fast transmission of electrons and ions during charge-discharge process. [ABSTRACT FROM AUTHOR]

Conventional state of health (SoH) estimation is often based on the capacity or resistance of lithium-ion cells. However, online capacity or resistance measurements are rarely achievable in electric vehicles. An alternative indicator should replace capacity and resistance to make online SoH diagnosis more manageable. In this paper, we introduce a novel SoH indicator, which is extracted from the cell temperature variation rate curve during the constant current charge process. There are two observable cooling areas in the temperature variation rate curve. The distance between these two areas, defined as t min , could serve as a gauge for cell SoH if electrode active material loss is negligible during the operation. In order to validate the assumption, test data from both calendar aging and cycle life tests on a commercial lithium-ion pouch cell is utilized. From the 544 aging data units, a linear correlation is observed between t min and SoH with a product-moment correlation coefficient of 0.954. The same correlation is found for all the tested cells under different aging conditions, which makes t min a promising indicator for SoH estimation. [ABSTRACT FROM AUTHOR]

The behaviour of Na 2/3 Co 2/3 Mn 2/9 Ni 1/9 O 2 in composite electrodes is studied via Na half-cells utilizing a dedicated cyclic voltammetry approach. The application of increasing sweep rates enabled a detailed analysis of the red-ox peaks of this material. All peak currents due to cathodic/anodic processes demonstrated clear capacitive properties. This finding widens the picture of classical Na + insertion/extraction in this complex oxide, as purely diffusive processes of Na + through its layers do not fully explain the pseudocapacitance displayed by its red-ox peaks, which are typically linked to concomitant oxidation state changes for its transition metal atoms and/or phase transitions. No phase transition was observed during in operando X-Ray diffraction upon charge to 4.2 V vs. Na + /Na, proving good structural stability for P2-Na x Co 2/3 Mn 2/9 Ni 1/9 O 2 upon Na + removal. The origin of such pseudocapacitive properties is likely nested in strong electrostatic interactions among the metal oxide slabs and a tendency to release Na + from its crystallites, e.g. to form surface by-products upon air exposure. Such a reactivity induces defects (e.g. vacancies) in its lattice and charge compensation mechanisms are required to maintain an overall charge neutrality, thus ultimately influencing the electrochemical properties. Possible limiting factors for the performances of this compound in composite coatings are also discussed. [ABSTRACT FROM AUTHOR]

Electron transfer and lithium ion diffusion rates are the key factors leading to sluggish electrochemical kinetics of LiMn 0.8 Fe 0.2 PO 4 . In this work, we have successfully synthesized graphene-embedded LiMn 0.8 Fe 0.2 PO 4 composites via a facile graphene oxide assisted solvothermal route associated with carbonthermal treatment. The effect of graphene on the morphology, crystalline structure as well as electrochemical properties of LiMn 0.8 Fe 0.2 PO 4 is investigated. It can be found that the introducing graphene can reduce the particle size to form LiMn 0.8 Fe 0.2 PO 4 nanocrystals without destroying the crystalline structure of LiMn 0.8 Fe 0.2 PO 4 . And the LiMn 0.8 Fe 0.2 PO 4 nanocrystals dispersed on the graphene sheets which were further cross-linked via the oxygen-containing groups of GO as cross-linking sites, resulting in that graphene sheets embedded in the LiMn 0.8 Fe 0.2 PO 4 composites. Benefiting from the LiMn 0.8 Fe 0.2 PO 4 nanocrystal and embedded graphene, the interconnected conducting network referred to electron and lithium ion transport pathways can be improved, resulting in enhanced electrochemical performance. The graphene embedded LiMn 0.8 Fe 0.2 PO 4 composite displays a high discharge capacity of 163.5, 149.2, 136.0, 120.6, 100.1 and 84.5 mA h g -1 at various rate of 0.1C, 0.5C, 1C, 2C, 5C and 10C, respectively. Meanwhile, it still maintains a reversible capacity of around 120 mA h g -1 after 100 cycles at a rate of 1C. [ABSTRACT FROM AUTHOR]

The development of advanced anode materials is the crucial to the enhanced performance of sodium ion batteries, which is a potential substitute to lithium ion batteries. In this work, two-dimensional coupling nanostructures with Sb nanoplates embedded ultrathin few-layered MoS 2 nanosheets (MoS 2 /Sb) have been synthesized through a one-pot solvothermal method. The assembled sodium battery with the anode of MoS 2 /Sb yields a high reversible capacity of 666 mAh g −1 and 454 mAh g −1 at current densities of 0.1 A g −1 and 10 A g −1 , respectively, demonstrating its good cyclicity and rate performance. The tightly embedded contact between ultrathin MoS 2 nanosheets and Sb nanoplates not only improve the electronic conductivity, but accommodate the volume expansion of metallic Sb and prevent the restacking of few-layer MoS 2 nanosheets. Therefore, the synergetic effects of the two dimensional nanocomponents are responsible for their excellent performance. [ABSTRACT FROM AUTHOR]

A novel SiOx@C composite is designed that uses benzene for both the homogenous dispersion of the Si source and simultaneous fabrication of a multiple carbon matrix on the composite. The overall morphology of the SiOx@C composite and uniformly carboncoated Si nanoparticles are verified using transmission electron microscopies with elemental mapping. This benzene-based synthesis process results in exceptional electrochemical properties for SiOx. At a current density of 0.5 A g−1, the SiOx@C composite delivers a discharge capacity of 591 mAh g−1 with 99% coulombic efficiency over 600 cycles. Furthermore, the SiOx@C composite exhibits outstanding power capability with a capacity of 602 mAh g−1 at a current density of 2 A g−1, corresponding to ~68% of that measured at 0.1 A g−1. In contrast, the capacity of pristine SiOx is extremely degraded under similar conditions [ABSTRACT FROM AUTHOR]

Recently, Cu element has been introduced into layered sodium transition metal oxides (NaxTMO2) as cathode materials for sodium ion batteries to engineer rate and cycling performance. To study the unique role provided by Cu, we designed, synthesized and tested four different compositions of P2-type Nax(MnyFezCo1-y-z)O2 and three compositions of P2-type Nax(MnyFezCo1-y-z)O2 cathode materials. When cycled in the full voltage range of 1.5~4.5 V under different rates 0.1 C, 1 C and 10 C, the cyclability of MnFeCu-based compounds is better than that of MnFeCo-based ones. Using X-ray diffraction, we observed the P2 to O2-like phase transition of MnFeCu-based materials upon charging and studied its influence on battery performance. Limiting the P2-O2 phase transition delivers less capacity, but improves cyclability. By DFT simulations, we showed that different Na diffusivity and site preference in the high voltage phase contribute to the difference in the electrochemical performances of these cathode materials. [ABSTRACT FROM AUTHOR]

Phosphorus-encapsulated carbon nanotubes with nanopores on the sidewalls (P@DMWCNTs) were investigated as an improved anode material with high capacity for lithium ion batteries in order to achieve reversible insertion/extraction reactions of lithium ions through the nanoporous sidewalls with the effective pathway of lithium ions. A P@DMWCNT anode demonstrated excellent reversible capacities of approximately 850 mAh/g with high Coulombic efficiencies of 99.9% at the fiftieth charge-discharge cycle. However, lithium metal and/or lithium oxides were deposited on the surface of the anode, resulting in capacity fading compared with the capacity of <1900 mAh/g at the first cycle. On the other hand, transmission electron microscopic (TEM)/energy dispersive X-ray spectroscopic (EDX) images and X-ray photoelectron spectroscopic (XPS) spectra indicated that phosphorus was stably encapsulated into the carbon nanotubes after the charge-discharge cycles. They suggest that a P@DMWCNT anode shows partially-reversible reactions assuming xLi + P↔LixP during charge-discharge cycles. [ABSTRACT FROM AUTHOR]

The reliability and safety of battery operations necessitate an efficient battery management system (BMS) with accurate battery state of charge (SOC) and capacity estimation techniques. This paper investigates the incremental capacity analysis (ICA) and differential voltage analysis (DVA) methods for onboard battery SOC and capacity estimation. Since the conventional cell terminal voltage based ICA/DVA methods are sensitive to the changed battery resistance and polarization during battery aging processes, the SOC based ICA/DVA methods are proposed to address this problem as so to accurately identify features of interest on incremental capacity (IC) and differential voltage (DV) curves for applications. Three feature points (FPs) that are potential to be easily identified by battery management systems are extracted from the SOC based IC/DV curves, and then the relations between FPs and cell SOCs/capacities are quantified and applied for battery SOC and capacity estimation. The robustness of the proposed approach against various aging levels and erroneous cumulative capacities is evaluated. Promising results with the maximum absolute error of 1.0% and the relative error of 2.0% can be achieved for battery SOC and capacity estimation, respectively. [ABSTRACT FROM AUTHOR]

Exploring suitable electrode materials with high rate capability and long-term cycling stability for sodium-ion batteries (SIBs) is of great importance but still challenging. In this work, we report a facile strategy to synthesize the nanocomposite of porous NaTi 2 (PO 4 ) 3 nanoparticles coated with a thin carbon layer (NTP/C). The unique structural and component merits endow the NTP/C nanocomposite with excellent charge transfer kinetics and enhanced structural stability. Compared with the pristine NTP nanoparticles, the NTP/C nanocomposite exhibits significant enhanced rate capability (108.9 mA h g −1 at 0.2C and 55.0 mA h g −1 at 20C) and long-term cycling performance (capacity retention of 78.8% after 2000 cycles at 10C). The electrochemical results indicate the NTP/C nanocomposite could be a high-performance anode material for SIBs. [ABSTRACT FROM AUTHOR]

Previously, a highly efficient reduced order model (ROM) for Li(MnNiCo)O 2 /Graphite polymer battery based on electrochemical principles has been developed for real time applications. The execution time is significantly reduced compared to that of the electrochemical thermal full order model while beginning of life of the battery with the approximately same accuracy can be predicted. However, prediction of the end of life associated with degradation effects of battery was not included. Our investigations on aging mechanisms of the Li(MnNiCo)O 2 (MNC) lithium ion batteries have revealed that side reaction is the main cause among others for capacity and power fade of the battery. The production of the side reaction forms thin unsolvable layers that adhere to the surface of the graphite particles and grow as cycled, which is called solid electrolyte interphase (SEI). Growth of the SEI leads to loss of the lithium ions, loss of the electrolytes and loss of the active volume fraction. These effects are described using the Butler-Volmer kinetics and aging parameters. Particularly, electrolyte solvent diffusion described by Fick's law is integrated into the degradation model, which results in quantifying the electrolyte solvent concentration in SEI. The exchange current density of the side reaction is formulated as a function of electrolyte solvent and lithium ion concentration, which justifies the reaction rate in the aspect of reactants. In addition, temperature dependency of the model parameters is also considered by adopting the energy equations. Finally, the degradation model is incorporated into the ROM. Performances of the integrated ROM are compared with the experimental data collected from a high power pouch type lithium ion polymer battery with Li [MnNiCo]O 2 /Graphite chemistry. [ABSTRACT FROM AUTHOR]