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Our review provides a brief overview of efficient QDs, synthesis, strategies for designing QDs based PV cells, shortcomings, and suggestions to overcome the drawbacks that limit efficiency.
DOI: 10.1038/s41560-024-01450-9 A research breakthrough in solar energy has propelled the development of the world's most efficient quantum dot (QD) solar cell, marking a significant leap toward the commercialization of next-generation solar cells. This
A quantum dot solar cell (QDSC) is a solar cell design that uses quantum dots as the captivating photovoltaic material. It attempts to replace bulk materials such as silicon, copper indium gallium selenide (CIGS) or cadmium telluride (CdTe). Quantum dots have bandgaps that are adjustable across a wide range of energy levels by changing their size.
Spin-cast quantum dot solar cell built by the Sargent Group at the University of Toronto. The metal disks on the front surface are the electrical connections to the layers below. A quantum dot solar cell (QDSC) is a solar cell design that uses quantum dots as the captivating photovoltaic material.
The first report on the efficiency of Quantum Dot Sensitized Solar Cells (QDSSCs) was 0.12%. As of today, the efficiency is reported as 18.1 %, and further, the researchers are working to improve the efficiency of QDSSCs. 1. Introduction Energy is an essential part of modern life, leading to ever-increasing consumption across the world.
"Quantum dot breakthrough could lead to cheap spray-on solar cells". Gizmag.com. Retrieved 2014-06-22.
Quantum dot solar cells have the potential to increase the maximum attainable thermodynamic conversion efficiency of solar photon conversion up to about 66% by utilizing hot photogenerated carriers to produce higher photovoltages or higher photocurrents.
The 21700 battery is a Li-ion battery named after its 21mm × 70mm cylindrical size (diameter × height). When compared to AA size and 18650 type cells, their height and diameter both are larger.
The diameter of the 21700 battery is 21mm. To be more precise, it has an approximate length of 70mm and an approximate diameter is 21mm but technically 21700 cell size is allowed with some tolerance in length and diameter. Thus you could find specifications written as (say) 21 ± 0.41mm ✖ 70 ± 0.25mm on the datasheet and features of the li-ion cell.
21700 cell, as the name suggests, stands for a cylindrical cell with 21mm width and 70mm height. It was first introduced in 2017 by a Tesla and Panasonic collaboration. 21700 was introduced as an alternative to the long-running 18650 model, which was introduced by Sony in 1991.
The 21700 cell increased the working volume over the 18650 by a factor of >1.4x 21700 => ~21mm in diameter and ~70.0mm long These dimensions vary between manufacturers. Using data from the Cell Database we can see that 70g is a good nominal figure for the mass of a 21700 cell. The 21700 cell by definition should be 21mm in diameter and 70mm high.
However, most 21700 cells are based on lithium-ion (Li-ion) technology, which is widely used across many types of rechargeable batteries due to its excellent energy density and long lifespan. There are several types of lithium-ion chemistries that could be used within the 21700 format:
The most significant difference between the 21700 and 18650 batteries is their size and capacity. The 21700 is larger (21mm x 70mm) compared to the 18650 (18mm x 65mm), and this size difference allows the 21700 to store more energy. Capacity: The 21700 typically holds 5000mAh or more, while the 18650 generally maxes out around 3500mAh.
One of the key advantages of 21700 batteries is their energy density. Typically, 21700 batteries have an energy density ranging from 250 Wh/kg to 300 Wh/kg, depending on the chemistry used. This is a notable improvement compared to 18650 batteries, which usually offer around 180 Wh/kg to 250 Wh/kg.
The top 10 lithium-ion battery manufacturers in the world in 2024 includes:CATL (Contemporary Amperex Technology Co., Limited)LG Energy Solution, Ltd. Panasonic CorporationSAMSUNG SDI Co.
10. BYD Company Ltd. BYD Company Ltd. manufactures and sells rechargeable batteries, including NiMH, lithium-ion, and NCM batteries. The company mainly serves the electronics, automobiles, new energy, and rail transit industries and has established over 30 industrial parks across six continents globally.
13. Lithion Battery Inc. Lithion Battery Inc. is a vertically integrated manufacturer of primary and secondary battery cells, rechargeable and non-rechargeable battery packs, and battery modules. The company boasts a full range of in-house engineering, design, and testing capabilities – offering one-stop, comprehensive energy and power solutions.
As per the analysis by IMARC Group, the top lithium-ion battery companies are focusing on developing and designing technologically advanced product variants. They are also making heavy investments in research and development (R&D) activities to introduce miniaturized lithium-ion batteries with improved efficiency.
Companies operating in this sector, such as Samsung SDI and Contemporary Amperex Technology Co., Limited, produce numerous products varying from small-sized Li-ion batteries to large power devices. These batteries are essential in numerous applications, including electronic devices, electric vehicles (EVs), and renewable energy storage systems.
In 1999, LG Chem made Korea's first lithium-ion battery. Later, in the 2000s, it supplied batteries for the General Motors Volt. After that, the company became a key supplier for many global car brands, such as Ford, Chrysler, Audi, Renault, Volvo, Jaguar, Porsche, Tesla, and SAIC Motor.
Samsung SDI is a major supplier of lithium-ion batteries for EVs. It develops and supplies key battery materials like cathode materials, which are crucial for the performance and efficiency of lithium-ion batteries. The company has secured supply agreements with leading automakers, including Stellantis, Rivan, BMW, and Volkswagen Group.
Open-circuit voltage of an individual cell in the range of 1 V. 2 V Determined by the particular chemistry For higher terminal voltages, multiple cells are connected in series.
Vanadium flow batteries employ all-vanadium electrolytes that are stored in external tanks feeding stack cells through dedicated pumps. These batteries can possess near limitless capacity, which makes them instrumental both in grid-connected applications and in remote areas.
Their single vanadium element system avoids capacity fading caused by crossover contamination in iron-chromium flow batteries (ICFBs) . Additionally, VRFBs use an aqueous electrolyte, eliminating the safety risks associated with bromine vapor corrosion in zinc-bromine flow batteries (ZBFBs) .
A laboratory-scale single cell vanadium redox flow battery (VRFB) was constructed with an active area of 64 cm 2. The electrolyte was produced by dissolving vanadium pentoxide in sulphuric acid.
Vanadium redox flow battery is one of the most promising devices for a large energy storage system to substitute the fossil fuel and nuclear energy with renewable energy. The VRFB is a complicated device that combines all the technologies of electrochemistry, mechanical engineering, polymer science, and materials science similar to the fuel cell.
The ideal electrolyte for vanadium batteries needs to ensure the stability of high-concentration vanadium ions in different oxidation states over a wide temperature range. A key issue to be resolved is to improve the stability of V 5+ at high temperatures (50 °C) and V 3+ at low temperatures (−5 °C).
Furthermore, research progress in other battery fields shows that optimizing electrolyte formulations [21, 22] and ion transport [23, 24] can significantly enhance energy density and cycling stability, providing valuable insights for improving vanadium redox flow battery electrolytes. Table 1.
The top 5 companies shipping the most in 2023 remained CATL, BYD, EVE Energy, REPT BATTERO, and Hithium. CATL led with shipments exceeding 70 GWh.
As the largest battery cell supplier, CATL occupies the top spot, with a shipment volume of 16.7GWh, accounting for 27.9%. Samsung SDI as one of top 10 energy storage battery cell manufacturers was established in 1970 to manufacture and sell batteries worldwide.
Specializing in the research and development, manufacturing and sales of new energy vehicle power battery systems and energy storage, the world's leading new energy innovation technology company. As the largest battery cell supplier, CATL occupies the top spot, with a shipment volume of 16.7GWh, accounting for 27.9%.
The top five largest energy storage cell manufacturers in the first half are CATL, EVE Energy, REPT, Hithium, and BYD. CATL secured the top position with orders from major customers like Tesla and Fluence. EVE Energy received orders from all big customers, sustaining second place in the industry.
The Japanese market mostly supplies local brands. Amperex Technology Limited (ATL) as top 10 energy storage battery cell manufacturers in the world was established in 1999. It is a well-known lithium-ion battery producer and innovator in the industry. It provides high-quality rechargeable lithium-ion battery cells, packaging and system integration.
In 2024, global and Chinese energy storage battery shipments will continue to grow, and it is expected that China's energy storage battery shipments will exceed 200GWh, accounting for about 88%.
According to statistics, the world's energy storage battery shipments in 2023 are 173GWh, an increase of 60% year-on-year, of which China's energy storage battery shipments are about 159GWh, accounting for 92%.
The anode and cathode materials are mixed just prior to being delivered to the coating machine. This mixing process takes time to ensure the homogeneity of the slurry. Cathode: active material (eg NMC622), polymer binder (e.g. PVdF), solvent (e.g. NMP) and conductive additives (e.g. carbon) are batch mixed. The anode and cathodes are coated separately in a continuous coating process. The cathode (metal oxide for a lithium ion cell) is coated onto an aluminium electrode. The. The electrodes up to this point will be in standard widths up to 1.5m. This stage runs along the length of the electrodes and cuts them down in width to. Immediately after coating the electrodes are dried. This is done with convective air dryers on a continuous process. The solvents are recovered from this process. Infrared technology is used as a booster on Anode lines.
[PDF Version]Battery cell production is divided into three main steps: (i) Electrode production, (ii) cell assembly, and (iii) cell formation and finishing . While steps (1) and (2) are similar for all cell formats, cell assembly techniques differ significantly . Battery cells are the main components of a battery system for electric vehicle batteries.
The manufacture of the lithium-ion battery cell comprises the three main process steps of electrode manufacturing, cell assembly and cell finishing. The electrode manufacturing and cell finishing process steps are largely independent of the cell type, while cell assembly distinguishes between pouch and cylindrical cells as well as prismatic cells.
lithium-ion battery production. The range stationary applications. Many national and offer a broad expertise. steps: electrode manufacturing, cell assembly and cell finishing. cells, cylindrical cells and prismatic cells. each other. The ion-conductive electrolyte fills the pores of the electrodes and the remaining space inside the cell.
The cell is filled with an electrolyte, which is composed of lithiumhexafluorophosphate (LiPF6) conductive salt . The manufacturing process of the cell is the one described in . The data for the energy consumption of the battery cell manufacturing are taken from .
The battery manufacturing process is a complex sequence of steps transforming raw materials into functional, reliable energy storage units. This guide covers the entire process, from material selection to the final product's assembly and testing.
Electrode manufacturing is the first step in the lithium battery manufacturing process. It involves mixing electrode materials, coating the slurry onto current collectors, drying the coated foils, calendaring the electrodes, and further drying and cutting the electrodes. What is cell assembly in the lithium battery manufacturing process?
Heterojunction solar cells (HJT), variously known as Silicon heterojunctions (SHJ) or Heterojunction with Intrinsic Thin Layer (HIT), are a family of technologies based on a formed between semiconductors with dissimilar. They are a hybrid technology, combining aspects of conventional crystalline solar cells with.
Heterojunction solar cells (HJT), variously known as Silicon heterojunctions (SHJ) or Heterojunction with Intrinsic Thin Layer (HIT), are a family of photovoltaic cell technologies based on a heterojunction formed between semiconductors with dissimilar band gaps.
Heterojunction solar panels are assembled similarly to standard homojunction modules, but the singularity of this technology lies in the solar cell itself. To understand the technology, we provide you with a deep analysis of the materials, structure, manufacturing, and classification of the HJT panels.
Silicon heterojunction solar cells (SHJ) is a promising candidate for cost-effective high-efficiency solar cells. The high performance is driven by a superior surface passivation provided by the solar cell structure where a thin silicon amorphous buffer layer separates the bulk from the highly recombinative metallic contacts.
In the case of front grids, the grid geometry is optimised such to provide a low resistance contact to all areas of the solar cell surface without excessively shading it from sunlight. Heterojunction solar cells are typically metallised (ie. fabrication of the metal contacts) in two distinct methods.
1.8W. The process requirements for manufacturing SHJ solar cells have several advantages compared with those for conventional homojunction c-Si solar cells. The first advantage is the low thermal budget during the heterojunction formation; the deposition temperature of a-Si:H and ITO layers is usually less than 250°C.
Heterojunction solar cells can be classified into two categories depending on the doping: n-type or p-type. The most popular doping uses n-type c-Si wafers. These are doped with phosphorous, which provides them an extra electron to negatively charge them.
The cans for the 18650 and 21700 are made from nickel plated steel and deep drawn in a two-stage process. The result is the base of the can is thicker than the cylindrical side wall. 1. 18650 1.1. Base thickness ~0.3mm 1.2. Wall thickness ~0.22 to 0.28mm 2. 21700 2.1. Base thickness ~0.3. Cylindrical cells are used in numerous applications and cooling varies from passive through to immersed dielectric cooling. The diameter, length and connection of the. Cylindrical cells are designed with a number of safety features including a defined vent path/weakness. The capacity is relatively small and.
Cylindrical lithium battery cells are generally used in power batteries, such as the typical 21700 battery cells carried in the Tesla Model 3, which once made 21700 popular in the battery cell market. However, cylindrical cells are not the only advantages; their shortcomings are also obvious.
This paper investigates 19 Li-ion cylindrical battery cells from four cell manufacturers in four formats (18650, 20700, 21700, and 4680). We aim to systematically capture the design features, such as tab design and quality parameters, such as manufacturing tolerances and generically describe cylindrical cells.
There are many types of cylindrical cells, such as 14650, 17490, 18650, 21700, 26650 and so on. Cylindrical lithium batteries are more prevalent in Japanese and Korean lithium battery companies, and there are also companies of appropriate scale in China that produce cylindrical lithium batteries. Ⅲ.
For instance, “65” represents a height of 65mm. Fifth Digit: The fifth digit indicates the cylindrical shape of the cell. Typically, it's “0” for cylindrical cells. By following this naming convention, we can easily identify the size and shape of cylindrical lithium-ion battery cells.
A generic overview of designing cylindrical Li-ion battery cells. Function 1: Two types of jelly roll designs can be distinguished: With tabs and tabless. Jelly rolls with tabs can be realized with a single tab (Design A) or several tabs in a multi-tab design (Design B).
The following is a common cylindrical cell structure; see the image below for details: Ordinary cylindrical lithium-ion batteries consist of a casing, a cap, a positive electrode, a negative electrode, a separator, and an electrolyte. Generally, the battery casing is the battery's negative electrode, and the cap is the battery's positive electrode.
Production Supervisor, Battery Cell ManufacturingLead and develop a motivated production teamCollaborate with engineering to enhance manufacturability and productivityDevelop training programs and support team member growthOversee issue resolution and maintain quality standardsDevelop and uphold standardized Manufacturing InstructionsEnsure safety and compliance, promoting continuous improvement.
If you want to make the switch and invest in some rechargeable batteries, we can help. We've done all the research for you if you just want to browse through our picks, but we also cover what you should look for in a rechargeable battery.
So, after getting deep knowledge of how rechargeable batteries work, here are some applications of rechargeable batteries mentioned below. Rechargeable batteries can be used for electricity generation distribution and in-stand-alone power systems. They can be used to power electric vehicles ranging from scooters to locomotives.
There are both environmental and financial benefits to using rechargeable batteries in lieu of standard batteries. Because rechargeable batteries allow you to buy less of them over time, you're creating less waste, both from dead batteries and packaging from new packs of batteries.
Marshall Brain, Charles W. Bryant, Clint Pumphrey & Yara Simón "How Batteries Work" 1 April 2000. Rechargeable Batteries - Rechargeable batteries are used in most electronics, such as cell phones, laptops, and mp3 players.
Different types of batteries have different charging characteristics and require specific charging methods. It is crucial to follow the manufacturer's guidelines and use the recommended charger to avoid overcharging. In conclusion, rechargeable batteries can be overcharged, especially lithium-ion batteries.
Rechargeable batteries have to be made of certain elements, like lithium, to allow for a safe recharging process. Non-rechargeable batteries are typically called alkaline batteries, with zinc and manganese dioxide as electrodes and either potassium or sodium hydroxide as the electrolyte solution dividing the two.
When the battery is discharged, the reactions occur in the opposite direction, releasing the stored energy. One of the main advantages of rechargeable batteries is that they can be used multiple times, reducing the number of batteries that end up in landfills.
For winter storage, disconnect the batteries, charge them to 50%, and store them in a dry, well-ventilated place. Don't let them get below -15°F (-26°C).
By following the right storage practices, you'll be ensuring your battery lasts longer, and your devices keep running smoothly for years to come. The first rule of battery storage is simple—never store a lithium-ion battery in an environment that's too hot or too cold. These batteries work best in moderate, room-temperature environments.
Regular maintenance and safety checks are important to ensure a safe environment for storing and handling lithium-ion batteries. This isn't a one-off task but an ongoing commitment, so scheduling regular inspections of your storage solutions is key. It's also important to keep an eye on the batteries themselves.
Follow guidelines for cleaning, disconnecting, and choosing the right storage location to safeguard your batteries. Monitoring and maintenance during winter storage are crucial for preserving lithium batteries. Regular inspection, temperature monitoring, and maintenance charging help ensure optimal battery health and performance.
The UK doesn't have specific regulations or legislation for the general storage of lithium-ion batteries. The Health and Safety Executive has, however, published guidance on good practices for handling and storing batteries, even though it is not compulsory. Regulations are not prescriptive but instead follow the typical routes:
Lithium-ion battery fires can even reignite after being contained. In this post, we'll talk through the safe storage requirements for lithium-ion batteries that manage the risks to keep people and facilities safe. The UK doesn't have specific regulations or legislation for the general storage of lithium-ion batteries.
Handle with Care: When handling the batteries, be mindful of their fragility and avoid dropping or mishandling them. Lithium batteries are sensitive to physical impact, and any damage to the battery casing can compromise their integrity and safety. 7.
You have a couple of recharging solutions to consider should your electric car run out of battery: If it is not possible to recharge at a nearby charging station then you can use a portable charger or call for a breakdown cover provider who will charge the EV with a partial charge or tow you to a charging station. Here's a. So, power is starting to run out or you've come to a complete stop, let's look at your options: 1. Find a nearby charging station Yep – captain obvious. The most common-sense answer is. Most EVs provide real-time information about the battery's state of charge, so it's really easy for drivers to see how low the battery is getting. Here are. Try to keep calm, this is stressful but panicking can make the situation worse. As soon as you notice your battery is running critically low or the car starts to lose power you should pull over safely onto the hard shoulder or. An electric car could potentially travel for around 10-40 miles on a low battery before running out of power (estimated for a battery of around 10%.
[PDF Version]You have a couple of recharging solutions to consider should your electric car run out of battery: If it is not possible to recharge at a nearby charging station then you can use a portable charger or call for a breakdown cover provider who will charge the EV with a partial charge or tow you to a charging station.
The best way to avoid running out of battery is to ensure you're never in that position; this is much easier nowadays with improved EVs. Be careful not to charge your EV to 100% too often or drain it to 0%, as doing either can damage your battery condition, limiting your battery life and range.
As soon as you notice your battery is running critically low or the car starts to lose power you should pull over safely onto the hard shoulder or the nearest safe area away from the traffic. Turn on your hazard lights to alert other drivers and place a warning triangle at a safe distance behind the car.
On the off chance you do run out of electricity, contact your breakdown provider. It may have a small battery booster that can give you enough charge to get to a charging station. If not, ask for a flatbed truck to take you to a nearby charging station.
When an electric car runs out of battery the power to the electric motor will eventually stop. The electric motor is pretty important, as you can imagine, it makes the vehicle drive! So the car will gradually lose speed and eventually come to a complete stop.
If you run out of battery power, there is less of a chance you'll damage your EV's powertrain than if you were to starve an internal combustion engine of fuel. For instance, EVs don't have a fuel pump or fuel filter that can be damaged by running the engine with an empty fuel tank. An EV will simply slow down and, eventually, completely shut down.
LiFePO4 batteries are generally considered to be safe. They do have some potential safety risks to be aware of. For example, they can still catch fire if damaged or subjected to extreme conditions, such as high temperatures or physical impact. It is important to handle LiFePO4 batteries with care and follow proper. To ensure the safety of LiFePO4 batteries, it is important to handle and maintain them properly. This includes charging them using a compatible. Compared to other lithium-ion battery chemistries, such as lithium cobalt oxide and lithium manganese oxide, LiFePO4 batteries are generally. Overall, LiFePO4 batteries are considered to be a safe choice for a variety of applications due to their high level of stability and built-in protection features.
Other lithium-ion battery chemistries, such as lithium cobalt oxide (LiCoO2) and lithium manganese oxide (LiMn2O4), have a high level of safety. Still, they have a higher risk of thermal runaway and overheating than LiFePO4 batteries.
Many still swear by this simple, flooded lead-acid technology, where you can top them up with distilled water every month or so and regularly test the capacity of each cell using a hydrometer. Lead-acid batteries remain cheaper than lithium iron phosphate batteries but they are heavier and take up more room on board.
LiFePO4 batteries are known for their high level of safety compared to other lithium-ion battery chemistries. They have a lower risk of overheating and catching fire due to their more stable cathode material and lower operating temperature. We have also mentioned this in our best LiFePO4 battery list.
One of the most attractive features of Lithium-ion batteries is their quick charging time compared to traditional lead acid batteries, making them an attractive option for those who work and live aboard. Credit: Cultura Creative RF/Alamy Credit: Cultura Creative RF/Alamy Lithium iron phosphate batteries: myths BUSTED!
Rechargeable lithium batteries have become an essential part of modern life, powering everything from portable electronics to solar energy systems. However, they are often surrounded by safety concerns—one of the most persistent myths being that these batteries pose a significant fire hazard.
A Comprehensive Guide LiFePO4 batteries, also known as lithium iron phosphate batteries, are rechargeable batteries that use a cathode made of lithium iron phosphate and a lithium cobalt oxide anode. They are commonly used in a variety of applications, including electric vehicles, solar systems, and portable electronics.
Lithium batteries' huge energy capacity means they last longer for each charge and are capable of easily 10 times more cycles (number of times they can be charged and discharged) than lead-acid batteries. Our lives are now so jammed full of technology of all kinds, and modern equipment and appliances are so power. The Ah number shows how much energy can be delivered by the battery over a period of time. So a 100Ah battery coulddeliver 100 Amps for. Depth of Discharge refers to the % you can discharge your battery. When you reach that % you must you must recharge. For lead-acid batteries, you can discharge your battery to 50%. Use. Lithium batteries extremely long lifespan and capability for a huge number of cycles means that it works out much cheaper than lead-acid batteries. Battery lifespan can be measure in cycles – that is discharge/charge cycles a battery is capable before it's ability to deliver power diminishes and it.
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The increase in battery demand drives the demand for critical materials. In 2022, lithium demand exceeded supply (as in 2021) despite the 180% increase in production since 2017. In 2022, about 60% of lithium, 30% of cobalt and 10% of nickel demand was for EV batteries. Just five years earlier, in 2017, these shares were. In 2022, lithium nickel manganese cobalt oxide (NMC) remained the dominant battery chemistry with a market share of 60%, followed by lithium iron phosphate (LFP) with a share of just under 30%, and nickel cobalt aluminium. With regards to anodes, a number of chemistry changes have the potential to improve energy density (watt-hour per kilogram, or Wh/kg). For example, silicon can be used to replace all or some of the graphite in the anode in.
The global sodium-ion battery market size was estimated at USD 321.75 million in 2023 and is expected to grow at a CAGR of 16.3% from 2024 to 2030. The global market is experiencing significant growth and is poised for further expansion in the coming years.
The market for sodium-ion batteries was estimated to be worth roughly USD 1120 million in 2021, and it is anticipated to grow to USD 2899 million by 2030. The market is expected to grow significantly over the coming years as a result of a number of driving factors.
Sodium-ion batteries play a crucial role in the transition towards cleaner and more abundant energy storage technologies and drive the Sodium-Ion Battery Market. The sodium-ion battery market demand is driven by the growing integration of renewable energy sources.
The sodium ion battery market in the U.S. is expected to grow at a CAGR of 18.9% from 2024 to 2030. Increasing demand for sodium-ion batteries from sectors like electric utilities, transportation (potentially for low-range EVs or commercial fleets), and industrial applications requiring reliable and cost-effective energy storage.
The sample report only takes 30 secs to download, no need to wait longer. The global sodium-ion battery market size was valued at USD 1025 million in 2021 and is estimated to reach an expected value of USD 2665 million by 2030, growing at a CAGR of 11.2% during the forecast period (2022 - 2030).
The Sodium-ion Battery market is divided into types and end-users for the purposes of our study. The sodium-Sulfur batteries category is predicted to rule the sodium-ion battery market in 2021 based on type. In sodium-sulfur (NAS) batteries, a type of sodium-ion battery, there is a lithium sulphide cathode and a sodium anode.