In recent years, graphite containing some proportion of SiO
-based materials for lithium-ion batteries has been investigated widely owing to its high specific capacity. An efficient binder is ...critical to maintain both the electronic and mechanical integrity of the SiO
-based graphite composite anode electrodes. In this study, we present a discussion on the water-soluble binders of styrene butadiene rubber (SBR) and poly acrylic acid (PAA) in a 15% SiO
-graphite composite anode with half cell (coin) and high voltage pouch battery. The peeling strength of the anode electrode using two binders was measured. The first coulombic efficiency and discharge specific capacity of SiO
-graphite was 83.6% and 626.5 mA h g
using the SBR as binder, while 81.2% and 636.1 mA h g
using the PAA binder, respectively. Based on the results from EIS, rate performance and the mechanism of the SBR emulsion binder, SBR binder is more conducive to the transfer of electrons and ions on the electrodes. In practical applications (high voltage pouch battery), the batteries with the PAA binder show better cycle performance and achieve lower swelling (7.49%) compared with those with the SBR binder (9.56%) at the 450th cycle in the range of 2.75-4.35 V.
Accurate state of charge (SOC) estimation plays a crucial role in the safe and efficient operation of batteries. The coulomb counting (CC) approach has been used extensively in industrial production ...as a relatively easy-to-use and reliable algorithm for estimating battery SOC. However, the accuracy of standard CC method is constrained and it cannot satisfy some complex operating environment requirements. In this paper, a CC approach based on non-destructive charge and discharge differentiation is proposed on NCM battery. This method corrects the battery's initial SOC value using the open-circuit voltage method. It also corrects the actual capacity of the battery based on temperature, discharge rate and aging. Finally, it corrects the CC method's cumulative error using non-destructive capacity differentiation (dQ/dV) and voltage differentiation (dV/dQ). Experimental results show the maximum estimation error of the proposed approach is 3.33 % in the temperature range of −10 °C to 45 °C which is 15.57 % lower than the traditional OCV - CC method at −10 °C.
•A coulomb counting approach based on non-destructive charge and discharge differentiation is proposed on NCM battery.•This method corrects the coulomb counting method's cumulative error using non-destructive capacity differentiation and voltage differentiation.•The maximum estimation error of the proposed approach is 3.33 % in the temperature range of −10 °C to 45 °C.
The tin (Sn)-modified HZSM-5 was employed to upgrade biomass pyrolysis volatiles to prepare bio-oil, and the deterioration of bio-oil and catalyst was focused. A new parameter indicating the ...physicochemical properties was defined as the comprehensive fuel-grade index (CFI). The catalyst initially demonstrated the better performance to transform oxygen-containing organics to hydrocarbons; consequently, the bio-oil had a higher CFI value. The fresh catalyst produced 33.43% of bio-oil with the higher hydrocarbon content of 41.60%, and the proportions of monocyclic aromatic hydrocarbons (MAHs) and light aliphatic hydrocarbons (LAHs) reached 74.59% and 20.02%, respectively. However, with the extension of catalyst using-time, the obvious decrease of hydrocarbons caused the significant decrease of CFI. Furthermore, the cracking and reforming diffusion performance supported by the acid and textural properties of the catalyst deteriorated severely, which contributed to the proportion increase of polycyclic aromatic hydrocarbons (PAHs). The decrease of the acid and textural properties were attributed to the coke generated and deposited into the pores and on the surface of the catalyst. The deposited cokes could be divided into two types including semihydrogenated coke and carbonaceous coke, and the former was the main one. The carbonaceous coke was formed in the initial stage of catalytic reaction, gradually inducing more precursors to cover active sites and block pores, and then generated more semihydrogenated coke, eventually causing the catalyst performance deterioration. This study provided an insight for improving sustainability in terms of understanding process deterioration.
In order to make full use of the heat in the internal combustion engine exhaust pipe, based on the typical working condition, the numerical distributions of the pressure and temperature field were ...carried out. The three-dimensional steady calculation model of the fluid-solid coupling system was established between the exhaust gas and the thermoelectric generator. The structure of the collector was optimized in consideration of the uniformity temperature of the hot end, the continuous operating temperature limit and the back pressure of the exhaust pipe. Simultaneously, a flow diversion control strategy was firstly proposed to divert the exhaust gas. The result showed that, when the length, width and height of the collector box was 400mm 100mm and 110mm, the temperature of the hot side was well-distributed under both conditions. The temperature of the hot end reached 168.80°C, the steady output power was 132W, and the back pressure was 16.8kPa under normal condition. Under extreme condition there were 201.38°C, 186W, and 13.8kPa. Combining with the continuous operating limit of the hot side of TEMs-230°C, this structure can meet the temperature requirements in the hot side and keep in the sustainable range of thermoelectric material through diversion control.
Exploring novel hole transport materials (HTMs) with high hole mobility and eco-friendly processability are imperative for the commercialization of perovskite solar cells (PSCs). However, there is a ...‘trade-off’ that the introduction of large-conjugated units aiming to ensure high hole mobility, inevitably compromises the green-solvent solubility of HTMs. In this work, a hybrid strategy of rigidity and flexibility is proposed, in which the conjugated unit is assembled by the rigid binaphthylamine core, and the amide-bond constitutes the flexible backbone. Polar solubilizing units ethylenedioxythiophene and thiophene are used as bridges to construct two kinds of polymers, cited as EDOT-SMe and T-SMe, respectively. Both polymers achieve high hole mobility, well-matched energy levels and efficient defect passivation effect toward the perovskite films. When processing the HTM films with the green solvent (2-methylanisole), the corresponding PSCs deliver fill factors as high as 82.7% for EDOT-SMe and 81.9% for T-SMe, respectively. Consequently, power conversion efficiencies of 20.25% for EDOT-SMe and 20.09% for T-SMe are realized, outperforming that of commercial polymer polybis(4-phenyl) (2,4,6-trimethylphenyl)amine (PTAA, 19.71%). Moreover, PSCs with these polyamides achieve good long-term stability. This work paves a new path for exploring efficient and green-solvent processable polymeric HTMs.
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•Two kinds of green-solvent processable polyamides are synthesized.•The polyamides are incorporated with multiple passivation anchors toward perovskite.•An improved long-term device stability is achieved by polyamide-based PSCs.
In this paper, functionalized carbon-anchored Li 4 Ti 5 O 12 (C-LTO) ultrathin nanosquares were synthesized via a combination of ball milling and solid state routes in a large scale. The resulting ...products were investigated by instrumental analyses such as XRD, SEM, HRTEM and IR. It was found that the transformation from microspheres to nanosquares was readily achieved through a “mechanical activation and Ostwald ripening” mechanism via examining the intermediate product structure at different reaction stages. This research indicates that C-LTO nanosquares with high crystallinity are a promising anode material for high-specific-energy in rechargeable lithium batteries.
Metal halide perovskite solar cells have received a lot of attention from researchers because of their excellent performance, and their efficiency has increased rapidly over the past decade and is ...now comparable to that of conventional crystalline silicon solar cells. Perovskite solar cells (PSCs) are currently most commonly constructed with SnO2 as an electron transport layer (ETL). Nevertheless, its existence of bulk phase defects and surface defects pose an impediment to developing a higher level as the most favorable electron transport layer. This paper suggests an efficient technique to decrease the defects of SnO2 through incorporating a metal halide SnF2 in planar (n-i-p type) perovskite solar cells. Divalent Sn in SnF2 is easily oxidized to tetravalent Sn, leading to more conversion of divalent Sn to tetravalent Sn, which inhibits the formation of oxygen vacancies from the source. F replaces defective sites, passivates oxygen vacancy defects, and reduces the content of hydroxyl oxygen on the surface. Doping SnF2 enhances the conduction band value and conductivity of SnO2, making the energy levels of the ETL and perovskite interfaces more compatible. This eliminates energy barriers in charge transport. Consequently, the fill factor of planar PSCs that were prepared through SnO2:SnF2 ETL exhibited an increase from 80.01% to 82.12%. Furthermore, the efficiency of PCE underwent an improvement from 21.43% to 22.65%.
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In recent years, graphite containing some proportion of SiO
x
-based materials for lithium-ion batteries has been investigated widely owing to its high specific capacity. An efficient binder is ...critical to maintain both the electronic and mechanical integrity of the SiO
x
-based graphite composite anode electrodes. In this study, we present a discussion on the water-soluble binders of styrene butadiene rubber (SBR) and poly acrylic acid (PAA) in a 15% SiO
x
-graphite composite anode with half cell (coin) and high voltage pouch battery. The peeling strength of the anode electrode using two binders was measured. The first coulombic efficiency and discharge specific capacity of SiO
x
-graphite was 83.6% and 626.5 mA h g
−1
using the SBR as binder, while 81.2% and 636.1 mA h g
−1
using the PAA binder, respectively. Based on the results from EIS, rate performance and the mechanism of the SBR emulsion binder, SBR binder is more conducive to the transfer of electrons and ions on the electrodes. In practical applications (high voltage pouch battery), the batteries with the PAA binder show better cycle performance and achieve lower swelling (7.49%) compared with those with the SBR binder (9.56%) at the 450th cycle in the range of 2.75-4.35 V.
The effects of water-soluble binder styrene butadiene rubber (SBR) and poly acrylic acid (PAA) for the 15% SiO
x
-graphite composite anode in half cell and high voltage pouch cell were investigated.
In this paper, functionalized carbon-anchored Li
4
Ti
5
O
12
(C-LTO) ultrathin nanosquares were synthesized
via
a combination of ball milling and solid state routes in a large scale. The resulting ...products were investigated by instrumental analyses such as XRD, SEM, HRTEM and IR. It was found that the transformation from microspheres to nanosquares was readily achieved through a "mechanical activation and Ostwald ripening" mechanism
via
examining the intermediate product structure at different reaction stages. This research indicates that C-LTO nanosquares with high crystallinity are a promising anode material for high-specific-energy in rechargeable lithium batteries.
Ultra-thin C-LTO nanosquares with high crystallinity were synthesized on a large scale and their electrochemical performance was measured in 18 650 batteries.
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