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A new type of battery that can charge ten times faster than a lithium-ion battery created

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A new type of battery that can charge ten times faster than a lithium-ion battery created

It is difficult to imagine our daily life without lithium-ion batteries. They dominate the small format battery market for portable electronic devices, and are also commonly used in electric vehicles. At the same time, lithium-ion batteries have a number of serious issues, including: a potential fire hazard and performance loss at cold temperatures; as well as a considerable environmental impact of spent battery disposal.

According to the leader of the team of researchers, Professor in the Department of Electrochemistry at St Petersburg University Oleg Levin, the chemists have been exploring redox-active nitroxyl-containing polymers as materials for electrochemical energy storage.

These polymers are characterised by a high energy density and fast charging and discharging speed due to fast redox kinetics. One challenge towards the implementation of such a technology is the insufficient electrical conductivity. This impedes the charge collection even with highly conductive additives, such as carbon.

Looking for solutions to overcome this problem, the researchers from St Petersburg University synthesised a polymer based on the nickel-salen complex (NiSalen). The molecules of this metallopolymer act as a molecular wire to which energy-intensive nitroxyl pendants are attached. The molecular architecture of the material enables high capacitance performance to be achieved over a wide temperature range.

‘We came up with the concept of this material in 2016. At that time, we began to develop a fundamental project “Electrode materials for lithium-ion batteries based on organometallic polymers”.

It was supported by a grant from the Russian Science Foundation. When studying the charge transport mechanism in this class of compounds, we discovered that there are two keys directions of development. Firstly, these compounds can be used as a protective layer to cover the main conductor cable of the battery, which would be otherwise made of traditional lithium-ion battery materials. And secondly, they can be used as an active component of electrochemical energy storage materials,’ explains Oleg Levin.

The polymer took over three years to develop. In the first year, the scientists tested the concept of the new material: they combined individual components to simulate the electrically conducting backbone and redox-active nitroxyl-containing pendants. It was essential to make certain that all parts of the structure worked in conjunction and reinforced each other.

The next stage was the chemical synthesis of the compound. It was the most challenging part of the project. This is because some of the components are extremely sensitive and even the slightest error of a scientist may cause degradation of the samples.

Of the several polymer specimens obtained, only one was found to be sufficiently stable and efficient. The main chain of the new compound is formed by complexes of nickel with salen ligands. A stable free radical, capable of rapid oxidation and reduction (charge and discharge), has been linked to the main chain via covalent bonds.

‘A battery manufactured using our polymer will charge in seconds – about ten times faster than a traditional lithium-ion battery. This has already been demonstrated through a series of experiments. However, at this stage, it is still lagging behind in terms of capacity – 30 to 40% lower than in lithium-ion batteries. We are currently working to improve this indicator while maintaining the charge-discharge rate,’ says Oleg Levin.

The cathode for the new battery has been fabricated – a positive electrode for use in chemical current sources. Now we need the negative electrode – the anode. In fact, it does not have to be created from scratch – it can be selected from the existing ones. Paired together they will form a system that, in some areas, may soon supersede lithium-ion batteries.

”The new battery is capable of operating at low temperatures and will be an excellent option where fast charging is crucial. It is safe to use – there is nothing that may pose a combustion hazard, unlike the cobalt-based batteries that are widespread today. It also contains significantly less metals that can cause environmental harm. Nickel is present in our polymer in a small amount, but there is much less of it than in lithium-ion batteries,’ says Oleg Levin.

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Innovative approach to perovskite solar cells achieves 24.5% efficiency

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Innovative approach to perovskite solar cells achieves 24.5% efficiency


Innovative approach to perovskite solar cells achieves 24.5% efficiency

by Simon Mansfield

Sydney, Australia (SPX) Mar 28, 2024






In groundbreaking research published in Nano Energy, a team led by Prof. CHEN Chong at the Hefei Institutes of Physical Science, part of the Chinese Academy of Sciences, has significantly improved the performance of perovskite solar cells (PSCs). By integrating inorganic nano-material tin sulfoxide (SnSO) as a dopant, they have boosted the photoelectric conversion efficiency (PCE) of PSCs to an impressive 24.5%.

Traditional methods of enhancing the charge transport in the critical hole transport layer (HTL) of PSCs involve the use of lithium trifluoromethanesulfonyl imide (Li-TFSI) to facilitate the oxidation of the HTL material spiro-OMeTAD. However, this method suffers from low doping efficiency and can leave excess Li-TFSI in the spiro-OMeTAD film, reducing its compactness and long-term conductivity. Additionally, the oxidation process typically requires 10-24 hours to achieve the desired electrical conductivity and work function.



The HFIPS team’s innovation lies in their development of a rapid and replicable method to control the oxidation of nanomaterials, using SnSO nanomaterial to pre-oxidize spiro-OMeTAD in precursor solutions. This novel approach not only enhances conductivity but also optimizes the energy level position of the HTL, culminating in a high PCE of 24.5%.



One of the key advantages of the SnSO-regulated spiro-OMeTAD HTL is its pinhole-free, uniform, and smooth morphology, which maintains its performance and physical integrity even under challenging conditions of high temperature and humidity. Additionally, the oxidation process facilitated by this method is significantly faster, taking only a few hours- a crucial factor in improving the commercial production efficiency of PSCs.



Prof. CHEN Chong highlighted the importance of this breakthrough, stating, “Also, the oxidation process only takes a few hours, which is good for improving the commercial preparation efficiency of PSCs.” This advancement not only marks a significant leap in the efficiency and stability of PSCs but also holds substantial implications for their commercial viability.



Research Report:A nanomaterial-regulated oxidation of hole transporting layer for highly stable and efficient perovskite solar cells


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Revolutionary technique boosts flexible solar cell efficiency to record high

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Revolutionary technique boosts flexible solar cell efficiency to record high


Revolutionary technique boosts flexible solar cell efficiency to record high

by Simon Mansfield

Sydney, Australia (SPX) Mar 28, 2024






Researchers at Tsinghua University have made a significant breakthrough in the efficiency of flexible solar cells, leveraging a novel fabrication technique to set a new efficiency record. This advancement addresses the longstanding challenge of the lower energy conversion efficiency in flexible solar cells compared to their rigid counterparts, offering promising implications for aerospace and flexible electronics applications.

Flexible perovskite solar cells (FPSCs), despite their potential, have historically lagged in efficiency due to the polyethylene terephthalate (PET)-based flexible substrate’s inherent softness and inhomogeneity. This limitation, coupled with durability issues arising from the substrate’s susceptibility to water and oxygen infiltration, has hindered the practical deployment of FPSCs.



The team from the State Key Laboratory of Power System Operation and Control at Tsinghua University, alongside collaborators from the Center for Excellence in Nanoscience at the National Center for Nanoscience and Technology in Beijing, introduced a chemical bath deposition (CBD) technique. This method facilitates the deposition of tin oxide (SnO2) on flexible substrates without the need for strong acids, which are detrimental to such substrates. Tin oxide is essential for the FPSCs as it acts as an electron transport layer, crucial for the cells’ power conversion efficiency.



Associate Professor Chenyi Yi, a senior author of the study, explained, “Our method utilizes SnSO4 tin sulfate instead of SnCl2 tin chloride, making it suitable for acid-sensitive flexible substrates. This approach not only enhances the efficiency of FPSCs but also their durability, with a new power conversion efficiency benchmark set at 25.09%, certified at 24.90%.”



The novel fabrication technique also contributes to the FPSCs’ stability, as demonstrated by the cells maintaining 90% of their initial efficiency after being bent 10,000 times. The researchers noted an improved high-temperature stability in SnSO4-based FPSCs over those made with SnCl2, pointing towards the dual benefits of efficiency and durability enhancements.



The research signifies a leap towards industrial-scale production of high-efficiency FPSCs, with potential applications ranging from wearable technology and portable electronics to aerospace power sources and large-scale renewable energy solutions. The team’s findings, supported by Ningyu Ren, Liguo Tan, Minghao Li, Junjie Zhou, Yiran Ye, Boxin Jiao, and Liming Ding, mark a pivotal step in transitioning FPSCs from laboratory to commercial use.



Research Report:25% – Efficiency flexible perovskite solar cells via controllable growth of SnO2


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KAUST advances in perovskite-silicon tandem cells

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KAUST advances in perovskite-silicon tandem cells


KAUST advances in perovskite-silicon tandem cells

by Sophie Jenkins

London, UK (SPX) Mar 28, 2024






In 2009, researchers introduced perovskite-based solar cells, highlighting the potential of methylammonium lead bromide and methylammonium lead iodide-known as lead halide perovskites-for photovoltaic research. These materials, notable for their excellent light-absorbing properties, marked the beginning of an innovative direction in solar energy generation. Since then, the efficiency of perovskite solar cells has significantly increased, indicating a future where they are used alongside traditional silicon in solar panels.

Erkan Aydin, Stefaan De Wolf, and their team at King Abdullah University of Science and Technology (KAUST) have explored how this tandem technology could transition from experimental stages to commercial production. Perovskites are lauded for their low-temperature production process and their flexibility in application, offering a lighter, more adaptable, and potentially cost-effective alternative to silicon-based panels.



Combining perovskite with silicon in a single solar cell leverages the strengths of both materials, enhancing sunlight utilization and reducing losses that aren’t converted into electrical energy. “The synergy between perovskite and silicon technologies in tandem cells captures a broader spectrum of sunlight, minimizing energy loss and significantly boosting efficiency,” Aydin notes.



However, Aydin and his colleagues acknowledge challenges in scaling tandem solar-cell fabrication for the marketplace. For instance, the process of depositing perovskite on silicon surfaces is complicated by the silicon’s texture. Traditional laboratory methods like spin coating are not feasible for large-scale production due to their inefficiency and material wastage. Alternatives such as slot-die coating and physical vapor deposition present their own set of advantages and challenges.



Moreover, the durability of perovskite components under environmental stressors such as moisture, heat, and light remains a critical concern. Aydin emphasizes the need for focused research to enhance the reliability and lifespan of perovskite/silicon tandem cells, especially in harsh conditions.



Although tandem modules have already been demonstrated in proof-of-concept stages, the timeline for their market readiness is uncertain. Nonetheless, the successful development of efficient, commercial-grade perovskite/silicon solar cells is essential for meeting global energy demands sustainably.



Research Report:Pathways toward commercial perovskite/silicon tandem photovoltaics


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All About Solar Energy at SolarDaily.com





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