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An advanced lithium-ion polymer battery (LIPB) has higher energy density, long-life cycle, and flexible configuration that can be arbitrarily shaped. It is the mainstream candidate for electronics products as energy storage device. However, an energetic LIPB will generate an abnormal electrochemistry reaction and will even cause spontaneous ignition to the battery pack in case cells fail, such as a short circuit or thermal runaway. Two commercial 603450 LIPBs, whose cathodes include lithium cobalt oxide (LiCoO₂, LCO) and lithium nickel cobalt manganese oxide (LiNi x Co y Mn z O 2 , NCM), were examined for their thermophysical data. Enhanced calorimetry methods are modified to analyse an LIPB's heat capacity and enthalpy. In case thermal runaway the heat capacity and enthalpy are 0.99 kJ g–1 K–1 and 11.76 kJ for an LCO cell and 0.96 kJ g–1 K–1 and 10.68 kJ for an NCM cell, respectively. Furthermore, TNT equivalency mass is 7.62 g for an LCO and 7.01 g for an NCM cell. An LIPB is examined to identify the fire-explosion behaviour and thermokinetic data for enhancing battery thermal management. [ABSTRACT FROM AUTHOR]

Nano-composite polymer electrolyte (NCPE), poly(vinylidenefluoride-hexafluoropropylene)-poly(methylmethacrylate) grafted natural rubber with lithium tetrafluoroborate and zirconia (PVdF-HFP/MG49-LiBF4-ZrO2) was prepared by a facile one-pot in situ sol–gel method. The influence of zirconia nano-fillers on the electrochemical, chemical and structural properties of polymer electrolyte was investigated. The interaction of polymer electrolyte and zirconia was explored via density functional theory (DFT). Electrochemical impedance spectroscopy study showed that the optimum ionic conductivity is 2.39 × 10−3 S cm−1 (6 wt% zirconia). X-ray diffractogram results revealed a decreasing trend of crystalline phases and no lithium salt peaks were observed upon the addition of zirconia. As a result, the LiBF4 salt was well-solvated in the polymer matrix with a one-fold increase in lithium transference number. Remarkably, a good electrochemical stability was achieved at 6.9 V from a linear sweep voltammetry (LSV) analysis. Observations from the infrared spectra indicate that chemical interactions occurred at the carbonyl and fluoride functional groups and is further corroborated by DFT studies. Micrograph images showed that the zirconia nano-particles were successfully produced (7–15 nm). The nanocomposite polymer electrolyte possesses promising charge/discharge performance and has the potential to be applied in lithium-ion polymer battery. The high electrochemical stability and flexible nanocomposite for lithium ion polymer battery application. The high electrochemical stability and flexible nanocomposite for lithium ion polymer battery application. Highlights: The sizes of ZrO2 nano-particles are in the range of 7–15 nm. High ionic conductivity (2.39 × 10−3 S cm−1) and electrochemical stability (6.9 V) was achieved for the nanocomposite polymer electrolyte sample. Nano-particle zirconia improved the lithium transference number by a fold from 0.103 to 0.216. The nanocomposite polymer electrolyte was able to maintain a good ionic conductivity (~10−5 S cm−1) at a high temperature of 200 °C. [ABSTRACT FROM AUTHOR]

Modelling, simulation, and validation of the 12-volt battery pack using a 20 Ah lithium−nickel−manganese−cobalt−oxide cell is presented in this paper. The cell characteristics influenced by thermal effects are also considered in the modelling. The parameters normalized directly from a single cell experiment are foundations of the model. This approach provides a systematic integration of actual cell monitoring with a module model that contains four cells connected in series. The validated battery module model then is utilized to form a high fidelity 80 Ah 12-volt battery pack with 14.4 V nominal voltage. The battery cell thermal effectiveness and battery module management system functions are constructed in the MATLAB/Simulink platform. The experimental tests are carried out in an industry-scale setup with cycler unit, temperature control chamber, and computer-controlled software for battery testing. As the 12-volt lithium-ion battery packs might be ready for mainstream adoption in automotive starting−lighting−ignition (SLI), stop−start engine idling elimination, and stationary energy storage applications, this paper investigates the influence of ambient temperature and charging/discharging currents on the battery performance in terms of discharging voltage and usable capacity. The proposed simulation model provides design guidelines for lithium-ion polymer batteries in electrified vehicles and stationary electric energy storage applications.

Application of gel polymer electrolytes (GPE) in lithium-ion polymer batteries can address many shortcomings associated with liquid electrolyte lithium-ion batteries. Due to their physical structure, GPEs exhibit lower ion conductivity compared to their liquid counterparts. In this work, we have investigated and report improved ion conductivity in GPEs doped with ionic liquid. Samples containing ionic liquid at a variety of volume percentages (vol %) were characterized for their electrochemical and ionic properties. It is concluded that excess ionic liquid can damage internal structure of the batteries and result in unwanted electrochemical reactions; however, samples containing 40–50 vol % ionic liquid exhibit superior ionic properties and lower internal resistance compared to those containing less or more ionic liquids.

As implantable devices become more sophisticated and their extended functionalities impact their energy requirements, they not only rely on charging for the extra energy but also become ever more sensitive to battery deep discharge or overcharge. Accurate state-of-charge (SOC) estimation plays a fundamental role in ensuring the operation safety of implantable medical devices. Temperature variation can impact the battery model parameters and directly affect the accuracy of SOC estimation. This study investigates a temperature-compensated model for lithium-ion polymer batteries that incorporates an extended Kalman filter method to estimate the state of the dynamic nonlinear system and its parameters, from 37 °C to 40 °C at intervals of 1 °C. Both simulation and experimental results indicate that the estimation error can be effectively limited to within ±3%. Through the accurate SOC estimation, the conventional constant current to constant voltage charging strategy is guided in order to reduce the charging time and increase the charging capacity. [ABSTRACT FROM PUBLISHER]

A new composite polymer electrolyte (CPE) containing a flame-retardant material, Mg(OH) 2 , is fabricated via a two-step process: porous poly(vinylidene-co-hexafluoropropylene) films composited with different Mg(OH) 2 contents are first prepared via casting and extraction steps, and they are then impregnated with a liquid electrolyte. As the Mg(OH) 2 content in the CPEs increases, their flame-retardant properties are greatly improved compared to those of the bare polymer electrolyte. Moreover, the better wettability of Mg(OH) 2 toward a liquid electrolyte leads to higher ionic conductivities of CPEs, thereby resulting in a better rate capability in LiCoO 2 /graphite lithium-ion polymer batteries (LiPBs). However, the Mg(OH) 2 content must be limited to less than 40 wt% to maintain the mechanical properties of the corresponding CPEs. [ABSTRACT FROM AUTHOR]

Recently Lithium-ion polymer (LiPo) battery attracts more interests in both technology and application for its high energy density and easy to be manufactured in different shapes. The LiPo battery quality is essential for all the applications, and the defect detection of LiPo cell sheets in the automatic production line is critical to battery quality control. After capturing the images of two sides of LiPo cell sheets with controlled manipulators in the automatic line, support Tucker machines (STM) method based on the tensor is applied to detect bubble defects in Lithium-ion polymer cell sheets. The preprocessing of the cell sheet images and the proposed STM based method are detailed. The experimental results demonstrate that the proposed STM based bubble defect detection method is more efficient than other common learning based methods, and the proposed STM based method is potential for classification in image applications. [ABSTRACT FROM AUTHOR]

In order to maximize the capacity/energy utilization and guarantee safe and reliable operation of battery packs used in electric vehicles, an accurate cell state-of-charge (SoC) estimator is an essential part. This paper tries to add three contributions to the existing literature. (1) An integrated battery system identification method for model order determination and parameter identification is proposed. In addition to being able to identify the model parameters, it can also locate an optimal balance between model complexity and prediction precision. (2) A radial basis function (RBF) neural network based uncertainty quantification algorithm has been proposed for constructing response surface approximate model (RSAM) of model bias function. Based on the RSAM, the average pack model can be applied to every single cell in battery pack and realize accurate terminal voltage prediction. (3) A systematic SoC estimation framework for multi-cell series-connected battery pack of electric vehicles using bias correction technique has been proposed. Finally, three cases with twelve lithium-ion polymer battery (LiPB) cells series-connected battery pack are used to verify and evaluate the proposed framework. The result indicates that with the proposed systematic estimation framework the maximum absolute SoC estimation error of all cells in the battery pack are less than 2%. [ABSTRACT FROM AUTHOR]

Accurate estimations of cell state-of-charge (SoC) for multi-cell series-connected battery pack are remaining challenge due to the inconsistency characteristic inhabited in battery pack and the uncertain operating conditions in electric vehicles. This paper tries to add three contributions. (1) A data-driven filtering process is proposed to select one represented cell to typify the voltage behavior of battery pack. (2) An improved battery model considering model and parameter uncertainties is developed. (3) An adaptive SoC estimator has been developed, in which the SoC of each cell in battery pack can be accurately predicted. The SoC of battery pack can be located with the SoC values of each cell. It significantly improves the safety operation of battery. The result indicates that the estimation errors of voltage and SoC for all the LiPB cells are less than 3% even if given big erroneous initial state of estimator. [ABSTRACT FROM AUTHOR]

Random copolymers comprising 2-(dimethylamino)ethyl methacrylate (DMAEMA) and methyl methacrylate (MMA) are synthesized by radical polymerization using 2,2′-azobis(2-methylpropionitrile) (AIBN) as an initiator. Gel polymer electrolytes (GPEs) are prepared by in situ thermal curing using different ratios of siloxane-epoxide cross-linker to poly(DMAEMA- co-MMA) and various contents and types of liquid electrolytes. GPEs offer several advantages such as in situ thermal cross-linking without requiring an additional radical initiator, relatively shorter curing time (~3 h) and lower curing temperature. When the ratio of the siloxane-epoxide cross-linker to poly(DMAEMA- co-MMA) is 1:5, the GPE with 98 wt% liquid electrolyte exhibits the highest ionic conductivity of 8.87×10 S/cm at 30 °C. The electrochemical stability window of the GPE is measured to be 5.1 V vs. Li/Li. A unit cell comprising LiCoO/GPE/graphite exhibits an initial discharge capacity of 145.6 mAh/g at 0.1 C, and the unit cell has good rate capability and cycling performance. [ABSTRACT FROM AUTHOR]

Abstract: We present a cross-linked gel polymer electrolyte for lithium-ion polymer batteries that can be easily synthesised without any initiators. The gel polymer electrolyte has a high ionic conductivity comparable to a liquid electrolyte, as well as favourable interfacial characteristics between the electrodes and the electrolyte during cycling. The lithium-ion polymer batteries assembled with cross-linked gel polymer electrolyte exhibit improved capacity retention and good rate capability. [Copyright &y& Elsevier]

Highlights: [•] A lumped parameter battery model against different battery aging levels is proposed. [•] The RLS based method is used to identify the parameter of battery model in real-time. [•] A data-driven based adaptive SoC estimator is developed by RLS and AEKF algorithm. [•] The robustness of the SoC estimator against varying loading profiles is evaluated. [•] The robustness of the SoC estimator against different aging levels is evaluated. [ABSTRACT FROM AUTHOR]

Highlights: [•] A data-driven multi-scale extended Kalman filtering is developed for battery system. [•] A lumped parameter battery model against different aging levels has been proposed. [•] The proposed approach has less computation efficiency but higher estimation accuracy. [•] The proposed approach can estimate battery parameter, capacity and SoC concurrently. [•] The robustness of the proposed approach against different aging levels is evaluated. [ABSTRACT FROM AUTHOR]

Abstract: An accurate SoC (state of charge) and SoP (state of power capability) joint estimator is the most significant techniques for electric vehicles. This paper makes two contributions to the existing literature. (1) A data-driven parameter identification method has been proposed for accurately capturing the real-time characteristic of the battery through the recursive least square algorithm, where the parameter of the battery model is updated with the real-time measurements of battery current and voltage at each sampling interval. (2) An adaptive extended Kalman filter algorithm based multi-state joint estimator has been developed in accordance with the relationship of the battery SoC and its power capability. Note that the SoC and SoP can be predicted accurately against the degradation and various operating environments of the battery through the data-driven parameter identification method. The robustness of the proposed data-driven joint estimator has been verified by different degradation states of lithium-ion polymer battery cells. The result indicates that the estimation errors of voltage and SoC are less than 1% even if given a large erroneous initial state of joint estimator, which makes the SoP estimate more accurate and reliable for the electric vehicles application. [Copyright &y& Elsevier]

Abstract: Time-dependent, thermal behaviour of a lithium-ion (Li-ion) polymer cell has been modelled for electric vehicle (EV) drive cycles with a view to developing an effective battery thermal management system. The fully coupled, three-dimensional transient electro-thermal model has been implemented based on a finite volume method. To support the numerical study, a high energy density Li-ion polymer pouch cell was tested in a climatic chamber for electric load cycles consisting of various charge and discharge rates, and a good agreement was found between the model predictions and the experimental data. The cell-level thermal behaviour under stressful conditions such as high power draw and high ambient temperature was predicted with the model. A significant temperature increase was observed in the stressful condition, corresponding to a repeated acceleration and deceleration, indicating that an effective battery thermal management system would be required to maintain the optimal cell performance and also to achieve a full battery lifesapn. [Copyright &y& Elsevier]

Abstract: A gel polymer electrolyte (GPE) was successfully prepared by means of an in situ cross-linking reaction of poly(2-vinylpyridine-co-styrene) and oligo(ethylene oxide) with epoxide functional groups at 65°C without using a polymerization initiator. A stable gel polymer electrolyte could be obtained by adding only 1% of a polymer gelator. The ionic conductivity of the GPE containing 99wt% of liquid electrolyte was measured to be ca. 10−2 S/cm at the ambient temperature. The ionic conductivity of the resulting GPE was comparable to that of a pure liquid electrolyte. The electrochemical stability window of the prepared gel polymer electrolytes was measured to be 5.2V. The test cell carried a discharge capacity of 133.2mAh/g at 0.1C and showed good cycling performance with negligible capacity fading after the 200th cycle, maintaining 99.5% coulombic efficiency throughout 200 cycles. The resulting gel polymer electrolyte prepared by in situ thermal cross-linking without a polymerization initiator holds promise for application to on the high power lithium-ion polymer batteries. [Copyright &y& Elsevier]

nion receptor-coated separators were prepared by coating poly(ethylene glycol) borate ester (PEGB) as an anion receptor and poly(vinyl acetate) (PVAc) as a good adhesive material towards electrodes onto microporous polyethylene (PE) separators. Gel polymer electrolytes were fabricated by soaking them in an liquid electrolyte, 1 M LiPF in EC/DEC/PC (30/65/5, wt.%). As the weight ratio of PEGB to PVAc in a coating layer increased, gel polymer electrolytes showed higher cationic conductivity and electrochemical stability. The cationic conductivity and electrochemical stability of the gel polymer electrolyte based on coated separator with PVAc/PEGB (2/5, weight ratio) could reach 2.8 × 10 S cm and 4.8 V, respectively. Lithium-ion polymer cells (LiCoO/graphite) based on gel polymer electrolytes with and without PEGB were assembled, and their electrochemical performances were evaluated. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports a modeling approach for the scale-up of a lithium-ion polymer battery (LIPB). A comparison of the experimental discharge curves with the modeling results confirmed that the parameters used to model a small-scale LIPB could be applied to a large-scale LIPB provided the materials and composition of the electrodes as well as the processes for manufacturing the batteries were the same. The potential and current-density distribution on the electrodes of a LIPB were predicted as a function of the discharge time using the finite element method. In addition, the temperature distributions of the LIPB were calculated based on the modeling results of the potential and current-density distributions. The temperature distributions from the model were in good agreement with the experimental measurements. [Copyright &y& Elsevier]

Abstract: The combination of graphite or silicon monoxide (SiO)/graphite=1/1 mixture with a solvent-free solid polymer electrolyte (SPE) was fabricated using a new preparation process, involving precoating the electrode with vapor-grown carbon fiber (VGCF) and binders (polyvinyl difluoride: PVdF or polyimide: PI), followed by the overcoating of the SPE. The reversible capacity of [graphite | SPE | Li] and [SiO/graphite | SPE | Li] cells were >360 and >1000mAhg−1 with 78% and 77% for the 1st Coulombic efficiency, respectively. The reversible capacities were 75% at the 250th cycle for [graphite | SPE | Li] and 72% at the 100th cycle for [SiO/graphite | SPE | Li]. The electrode used was compatible with that of the conventional liquid electrolyte system, and the SPE film could be formed on the electrode by the continuous overcoating process, which will lead to a low-cost electrodes and low-cost battery production. The solid-state lithium-ion polymer battery (SSLiPB) developed in this study, which consisted of [LiFePO4 | SPE | graphite], showed the reversible capacity of 128mAhg−1 (based on the LiFePO4 capacity) with favorable cycle performance. [Copyright &y& Elsevier]

Abstract: We tested 4.2V Li-ion polymer batteries (LIPB) with physical gel electrolyte, poly(vinylidene fluoride) (PVDF), 4.4V LIPB and 4.4V Li-ion batteries (LIB) with a liquid electrolyte. The discharge capacity of the 4.4V LIPB reached 520Whl−1 which was 9% higher than that of the 4.2V LIPB. The 4.4V LIPB had a high capacity retention ratio of 91.4% at 3C because of the excellent ion conductivity of the PVDF gel. The capacity retention ratio of the 4.4V LIPB was 82% after 500 cycles, which is comparable to those of some commercial LIBs. The 4.4V LIPB retained its original thickness even after many cycles and after being stored at 90°C, whereas the 4.4V LIB swelled by over 20%. Peaks in the FT-IR spectrum of the discolored separator in the 4.4V LIB after storage were assigned to Cbonds, suggesting that the separator in direct contact with the 4.4V cathode had been oxidized. The PVDF gel electrolyte not only had a high ionic conductivity but also completely suppressed oxidation. The 4.4V LIPB with PVDF gel electrolyte has properties suitable for practical cells, namely, high energy density, high permanence and it is safe to use. [Copyright &y& Elsevier]

Abstract: The overcharge performances of lithium-ion polymer batteries (LIPB) have been studied by monitoring their temperature variation and analyzing the generated heat during overcharge. The critical concentration of lithium in the cathode material is determined for the thermal runaway of the battery. Solutions against the thermal runaway are proposed based on these results. [Copyright &y& Elsevier]

Abstract: Gel-type polymer electrolytes are prepared using PVdF/PEGDA/PMMA, LiPF6/LiCF3SO3 mixed lithium salts and ceramic fillers such as Al2O3, BaTiO3 and TiO2. The electrochemical properties of these electrolytes, such as electrochemical stability, ionic conductivity and compatibility with electrodes are investigated in addition to the physical properties. The charge–discharge performances of lithium-ion polymer batteries using these get-type polymer electrolytes are investigated. The gel-type polymer electrolytes containing a mixed lithium salt of LiPF6/LiCF3SO3 (10/1, wt.%) exhibit more stable ionic conductivity and lower interfacial resistance than those containing only LiPF6. In addition, an Al2O3 filler improves interfacial stability between the electrode and the polymer electrolyte. Stacking cells (MCMB 1028/LiCoO2, 8cm×13cm×7ea) composed of gel-type polymer electrolytes based on PVdF/PEGDA/PMMA, LiPF6/LiCF3SO3 (10/1, wt.%) and Al2O3 filler maintain 95% of initial capacity after 100 cycles at a C/2 rate. [Copyright &y& Elsevier]

Abstract: The di(trimethylolpropane) tetraacrylate-based gel polymer electrolyte (GPE) was stable electrochemically up to 4.5V versus Li/Li+ and showed the ionic conductivity of 6.2×10−3 Scm−1 at room temperature. Lithium-ion polymer batteries with the GPE were prepared and their performances were also investigated. The battery showed good rate capability and low temperature performance. The cell delivered 95.1% of the initial discharge capacity at 1.0C rate after the 150th cycling. At the over-charged test, the temperature did not exceed 90°C and neither leakage of electrolyte nor explosion was observed in the cell. [Copyright &y& Elsevier]

Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) is one of the most popular polymers for polymer electrolyte membranes because of its excellent operating characteristics and superior electrochemical properties. The electrochemical performances of polymer electrolyte membrane can be enhanced by evenly dispersing nano-meter SiO2 particles in the polymer. In this paper, non-woven fabrics were immersed in the mixed solution of PVDF-HFP/ SiO2/butanone/butanol/plasticizer, and then dried in a vacuum oven to remove the solvents and the plasticizer and to make porous composite polymer electrolyte membranes. The prepared composite membranes supported by non-woven fabrics boast good mechanical strength and excellent electrochemical properties: the electrochemical stability window is 4.8 V vs. Li+/Li, and the ionic conductivity is 3.35x10-4 S/cm (around 60% of that of a common PE membrane) at room temperature. The lithium-ion polymer battery assembled by the composite membrane exhibits high rate capability and excellent cycling performance. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the cross-linking-type gel polymer electrolyte (GPE) was prepared using trimethylolpropane triacrylate and trimethylolpropane ethoxylate triacrylate and their electrochemical performances were evaluated. The ionic conductivity of the GPE at 20°C was around 5 × 10−3 ∼ 6 × 10−3 Scm−1. The GPE had good electrochemical stability up to 4.5V versus Li/Li+. The electrochemical performance of TMPETA-based cell was better than that of TMPTA-based cell. The discharge capacity of the TMPETA-based cell at the 2.0C rate was 98% of the discharge capacity at the 0.2C rate. The discharge capacity of the TMPTA- and TMPETA-based cell was stable with the charge–discharge cycling [Copyright &y& Elsevier]

Composite electrolytes composed of a blend of polyethylene glycol diacrylate (PEGDA), poly(vinylidene fluoride) (PVDF) and poly(methyl methacrylate) (PMMA) together with a non-woven fabric have been prepared by means of ultra-violet cross-linking. As the non-woven fabric serves as a mechanical support medium, the composite electrolyte has good integrity up to an initial liquid electrolyte uptake of 1000% (ethylene carbonate (EC)–dimethyl carbonate (DMC)–ethylmethyl carbonate (EMC)–LiPF6). The ionic conductivity of the composite electrolytes reaches 4.5 mS cm-1 at an ambient temperature of around 18 °C and are electrochemically stable up to about 4.8 V versus Li/Li+. The conductivity and interfacial resistance remain almost constant even at 80 °C. Scanning electron micrographs show that the high-temperature behavior is associated with structural stability that is induced by chain entanglement between PVdF, PMMA and PEGDA network. A MCMB|LiCoO2 cell using the composite electrolytes retains >97% of its initial discharge capacity after 100 cycles at the C/2 rate (150 mA), and delivers more than 80% of full capacity with an average load voltage of 3.6 V at the 2C rate. The cell also shows much better cycle-life than one with a PVdF-coated composite electrolyte at high temperatures because of the better liquid electrolyte retention capability. [Copyright &y& Elsevier]

The electrochemical and physical properties of composite polymer electrolytes based on a blend of poly(methyl methacrylate) (PMMA) and poly(ethylene glycol diacrylate) (PEGDA) are investigated. The addition of nanometre-size TiO2 filler decreases the crystallinity of the polymer electrolytes and also improves the ionic conductivity and the interfacial resistance between the electrode and the electrolyte. In addition, this ceramic filler enhances the mechanical strength of the electrolytes. A prototype battery, which consists of a graphite anode, a LiCoO2 cathode, and the composite polymer electrolyte coated on a poly(propylene) (PP) separator, shows good cycling performance at high rate. [Copyright &y& Elsevier]

A porous polyacrylonitrile (PAN) membrane was prepared and characterized. Gel polymer electrolytes were prepared from these porous membranes via soaking in an organic electrolyte solution. They showed high ionic conductivity (2.8×10−3 S/cm) at room temperature and sufficient electrochemical stability over 5.0 V that allowed application in lithium-ion polymer batteries. [Copyright &y& Elsevier]

The precursor for a gel polymer electrolyte (GPE) consisted of tetra (ethylene glycol) diacrylate monomer, benzoyl peroxide, and 1.1 M LiPF6/EC:PC:EMC:DEC (30:20:30:20 wt.%). LiCoO2/graphite cells were prepared and their electrochemical properties were evaluated at various current densities and temperatures. The viscosity of the precursor containing 5 vol.% tetra (ethylene glycol) diacrylate monomer was around 4.6 mPa s. The ionic conductivity of the gel polymer electrolyte at 20 °C was around 6.34×10−3 S cm−1. The gel polymer electrolyte had good electrochemical stability up to 4.5 V versus Li/Li+. The capacity of the cell at 2.0 C rate was 74% of the discharge capacity at 0.2 C rate. The capacity of the cell at temperature of −10 °C was 81% of the discharge capacity at temperature of 20 °C. Discharge capacity of the cell with gel polymer electrolyte was stable with charge–discharge cycling. [Copyright &y& Elsevier]

A gel polymer electrolyte (GPE) was prepared using tetra(ethylene glycol) diacrylate monomer, benzoyl peroxide, and 1.0 M LiPF6/EC-DEC (1 : 1 vol%). The LiCoO2/GPE/graphite cells were prepared and their electrochemical properties were evaluated at various current densities and temperatures.The viscosity of the precursor containing the 5 vol% tetra(ethylene glycol) diacrylate monomer was around 4.6 mPa s. The ionic conductivity of the gel polymer electrolyte at 20°C was around 5.9×10−3 S cm−1. The gel polymer electrolyte had good electrochemical stability up to 4.3 V vs. Li/Li+. The capacity of the LiCoO2/GPE/graphite cell at 2.0 C rate was 63% of the discharge capacity at 0.2 C rate. The capacity of the cell at −10°C was 81% of the discharge capacity at 20°C. Discharge capacity of the cell with gel polymer electrolyte was stable with charge–discharge cycling. [Copyright &y& Elsevier]

Modelling, simulation, and validation of the 12-volt battery pack using a 20 Ah lithium–nickel–manganese–cobalt–oxide cell is presented in this paper. The cell characteristics influenced by thermal effects are also considered in the modelling. The parameters normalized directly from a single cell experiment are foundations of the model. This approach provides a systematic integration of actual cell monitoring with a module model that contains four cells connected in series. The validated battery module model then is utilized to form a high fidelity 80 Ah 12-volt battery pack with 14.4 V nominal voltage. The battery cell thermal effectiveness and battery module management system functions are constructed in the MATLAB/Simulink platform. The experimental tests are carried out in an industry-scale setup with cycler unit, temperature control chamber, and computer-controlled software for battery testing. As the 12-volt lithium-ion battery packs might be ready for mainstream adoption in automotive starting–lighting–ignition (SLI), stop–start engine idling elimination, and stationary energy storage applications, this paper investigates the influence of ambient temperature and charging/discharging currents on the battery performance in terms of discharging voltage and usable capacity. The proposed simulation model provides design guidelines for lithium-ion polymer batteries in electrified vehicles and stationary electric energy storage applications. [ABSTRACT FROM AUTHOR]

Mobile power bank (MPB) is an emerging consumer electronic that stores and delivers electricity to other electronics. Nowadays, MPBs are produced and discarded in massive quantities, yet their environmental impacts have never been quantitatively evaluated. Employing a life cycle assessment (LCA) approach, this study assesses the life cycle environmental impacts of MPBs, with a specific focus on comparing the environmental performance of different MPBs that are based on two types of batteries, namely, lithium-ion battery (LIB) and lithium-ion polymer battery (LIPB). The results suggest that battery production is the greatest contributor to the environmental impacts of both MPBs. LIPB based MPB is environmentally friendlier due to its higher energy density and longer cycle life. In addition, it is found that recycling can reduce the environmental burden of MPB industry as well as ease the vast depletion of metals such as cobalt and copper. The sensitivity analysis shows that figuring out an optimal retirement point and using less carbon-intensive electricity can reduce the climate change potential of MPBs. This study provides recommendations to further improve the environmental performance of MPB, including the usage of more sustainable cathode materials, market promoting direction, and formulation of end-of-life management policy. [ABSTRACT FROM AUTHOR]