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Lithium-ion batteries don’t work well in the cold a battery researcher explains the chemistry at low temperatures – The Conversation

Rechargeable batteries are great for storing energy and powering electronics from smartphones to electric vehicles. In cold environments, however, they can be more difficult to charge and may even catch on fire.

Im a mechanical engineering professor whos been interested in batteries since college. I now lead a battery research group at Drexel University.

In just this past decade, I have watched the price of lithium-ion batteries drop as the production market has grown much larger. Future projections predict the market could reach thousands of GWh per year by 2030, a significant increase.

But, lithium-ion batteries arent perfect this rise comes with risks, such as their tendency to slow down during cold weather and even catch on fire.

The electrochemical energy storage within batteries works by storing electricity in the form of ions. Ions are atoms that have a nonzero charge because they have either too many or not enough electrons.

When you plug in your electric car or phone, the electricity provided by the outlet drives these ions from the batterys positive electrode into its negative electrode. The electrodes are solid materials in a battery that can store ions, and all batteries have both a positive and a negative electrode.

Electrons pass through the battery as electricity. With each electron that passes to one electrode, a lithium ion also passes into the same electrode. This ensures the balance of charges in the battery. As you drive your car, the stored ions in the negative electrode move back to the positive electrode, and the resulting flow of electricity powers the motor.

While AA or AAA batteries can power small electronics, they can be used only once and cannot be charged. Rechargeable Li-ion batteries can operate for thousands of cycles of full charge and discharge. For each cycle, they can also store a much higher amount of charge than an AA or AAA battery.

Since lithium is the lightest metal, it has a high specific capacity, meaning it can store a huge amount of charge per weight. This is why lithium-ion batteries are useful not just for portable electronics but for powering modes of transportation with limited weight or volume, such as electric cars.

However, lithium-ion batteries have risks that AA or AAA batteries dont. For one, theyre more likely to catch on fire. For example, the number of electric bike battery fires reported in New York City has increased from 30 to nearly 300 in the past five years.

Lots of different issues can cause a battery fire. Poorly manufactured cells could contain defects, such as trace impurities or particles left behind from the manufacturing process, that increase the risk of an internal failure.

Climate can also affect battery operation. Electric vehicle sales have increased across the U.S., particularly in cold regions such as the Northeast and Midwest, where the frigid temperatures can hinder battery performance.

Batteries contain fluids called electrolytes, and cold temperatures cause fluids to flow more slowly. So, the electrolytes in batteries slow and thicken in the cold, causing the lithium ions inside to move slower. This slowdown can prevent the lithium ions from properly inserting into the electrodes. Instead, they may deposit on the electrode surface and form lithium metal.

If too much lithium deposits on the electrodes surface during charging, it may cause an internal short circuit. This process can start a battery fire.

My research group, along with many others, is studying how to make batteries that operate more efficiently in the cold.

For example, researchers are exploring swapping out the usual battery electrolyte and replacing it with an alternative electrolyte that doesnt thicken at cold temperatures. Another potential option is heating up the battery pack before charging so that the charging process occurs at a warmer temperature.

My group is also investigating new types of batteries beyond lithium ion. These could be battery types that are more stable at wider temperature ranges, types that dont even use liquid electrolytes at all, or batteries that use sodium instead of lithium. Sodium-ion batteries could work well and cost less, as sodium is a very abundant resource.

Solid-state batteries use solid electrolytes that arent flammable, which reduces the risk of fire. But these batteries dont work quite as well as Li-ion batteries, so itll take more research to tell whether these are a good option.

Lithium-ion batteries power technologies that people across the country use every day, and research in these areas aims to find solutions that will make this technology even safer for the consumer.

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Lithium-ion batteries don't work well in the cold a battery researcher explains the chemistry at low temperatures - The Conversation

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SK On presents improved fast-charging battery and cold-proof LFP chemistry – www.electrive.com

The South Korean battery trade fair has been running since Wednesday at the Coex Convention & Exhibition Centre in Seoul. According to the company, the SF cell presented there by SK On has been improved, particularly in terms of energy density. The version of the cell with a high nickel content in the cathode presented in 2021 already offered a charging time of 18 minutes for the usual charging window of ten to 80 per cent. This charging time also applies to the 2024 version, although the energy density is said to be nine per cent higher resulting in a longer range with the same battery size or a smaller and cheaper battery with the same range. However, SK On does not specify whether the statement refers to the volumetric or gravimetric energy density.

According to SK On, it has succeeded in shortening the transport path of the lithium ions through a special coating process that drastically reduces the anode resistance, as well as through an anode alignment process. In addition, an optimised fast charging protocol with analysis solutions was also used in the development of the Advanced SF Battery in order to maximise the charging speed.

In addition to the Advanced SF Battery with the same charging time but higher energy density, SK On has also developed in the other direction and is also exhibiting the SF+ Battery in Seoul: This achieves a charging time of just 15 minutes, but there is no statement on energy density in the announcement.

To achieve a shorter charging time, the transport distance for the lithium ions in the SF+ Battery has been reduced and their movement speed increased at the same time, as the Koreans explain. This was achieved by applying high-capacity silicon with low-resistance graphite to the double-layer structure developed in-house.

In addition to the two new variants of the SF cell, the Winter Pro LFP cell was also presented at InterBattery. Generally, a LFP battery suffers 50~70 per cent drop in driving range it can offer at a low temperature (-20). However, compared to the existing conventional LFP, the Winter Pro LFP Battery extends the charging and discharging capacity by 16 per cent and 10 per cent, respectively, while increasing the energy density by 19 per cent, writes SK On about the new development. However, no further details were given.

At the battery trade fair, South Korean competitor Samsung SDI had also announced its intention to mass-produce solid-state batteries in 2027. Samsung SDI has been producing prototype cells with solid electrolyte since 2023, but had previously avoided making a statement on the start of mass production.

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The Fragrant Phenomenon: Christmas Trees and Their Invisible Affect on Indoor Air Chemistry – SciTechDaily

Researchers at NIST studied the emission of VOCs from live Christmas trees and their interaction with ozone. They found that monoterpenes are the primary VOCs emitted, which decrease over time and react with ozone to form low levels of formaldehyde. The study concludes that Christmas trees have a minimal impact on indoor air quality for most people. Credit: SciTechDaily.com

Every holiday season, Americans buy nearly 30 million live Christmas trees. Many families enjoy not only having a live tree inside their homes but also smelling the fresh fragrance it creates. That smell comes from chemicals called volatile organic compounds (VOCs). However, little is known about how much is emitted and whether they have any health impacts.

Our nose is a good chemical sensor, said Dustin Poppendieck, an environmental engineer at the National Institute of Standards and Technology (NIST). We know that these trees are emitting something, and the question then becomes: How big of a source is it? We wanted to explore which chemicals are emitted and how much, and to put that into the context of other sources of chemicals in a house, he said.

To answer these questions, Poppendieck and his NIST colleagues took a common type of Christmas tree a Douglas fir and sealed it inside a chamber. They then measured the amount and type of VOCs it emitted over 17 days. They also investigated whether the VOCs reacted with other components of indoor air to create new compounds.

The teams findings have been published in the journal Indoor Environments.

NIST researchers placed a common type of Christmas tree in a sealed chamber for 17 days to monitor and measure the chemicals it emits. These chemicals, called volatile organic compounds (VOCs), give that pine smell and can react with ozone to form byproducts. The researchers found low amounts of these chemicals, which may be a potential concern for people who are sensitive to them. Credit: M. King/NIST

The fresh smell that is commonly associated with Christmas trees comes from a group of VOCs called monoterpenes, which are also found in air fresheners, candles and some personal care products. In the outdoors, conifers, the group of plants that includes most Christmas trees, release monoterpenes, and they can affect outdoor air quality. But little is known about how much monoterpene is released when a tree is cut down and placed indoors.

Studies also show monoterpenes can react with ozone. Ozone in the upper atmosphere serves as a protective barrier against the Sun. At ground level, ozone is created through chemical reactions with light and can cause symptoms such as coughing and throat irritation. Ozone also reacts readily with other chemicals in the air to form new compounds. So, the researchers were interested in seeing the effects of ozone in the presence of an indoor tree.

They placed it inside an environmentally controlled chamber, where they could measure the chemicals emitted from the tree in real time. Using a technique that can detect airborne organic compounds, known as proton-transfer reaction mass spectrometry (PTR-MS), they measured the VOCs emitted over a 17-day period.

In their experiment, the researchers simulated a home environment. They decorated the tree in a typical holiday lighting setup and shone bright lights on it to mimic the day-night cycle. They turned off the lights every 12 hours and watered the tree every day. They brought in outside air at a rate typical for households, and constantly measured chemicals in the indoor air.

Monoterpenes were the most abundant VOC emitted from the tree. They peaked during the first day before diminishing significantly by the third day. Their concentration was initially at the same level of a plug-in air freshener or newly constructed house before it quickly dropped by nearly 10 times its original amount, said Poppendieck. The researchers detected 52 distinct types of monoterpenes.

Researchers then injected ozone into the chamber to see how it affected indoor air chemistry. They found that ozone reacted with the monoterpenes, forming byproducts such as formaldehyde, another type of VOC, as well as other reactive chemicals. The monoterpene concentration diminished even more with the introduction of ozone, while formaldehyde levels rose, which showed an impact on indoor air chemistry. However, the amount of formaldehyde created was relatively small at around 1 part per billion. Typical U.S. houses have formaldehyde concentrations ranging from 20 to 30 parts per billion.

For people who are sensitive to VOCs, Christmas trees could be one possible cause for watery eyes and noses, especially when initially brought indoors. In that case, Poppendieck suggests, opening a window near the tree will reduce exposure. In addition, newly cut trees can be left outdoors or in a garage for three days before bringing them into the home as the emission strength naturally decays over time.

But for most people, Poppendieck said, this shouldnt be a major concern. Im still going to have a Christmas tree in my house.

Reference: Jingle bells, what are those smells? Indoor VOC emissions from a live Christmas tree by Dustin Poppendieck, Rileigh Robertson and Michael F. Link, 22 December 2023, Indoor Environments. DOI: 10.1016/j.indenv.2023.100002

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The Fragrant Phenomenon: Christmas Trees and Their Invisible Affect on Indoor Air Chemistry - SciTechDaily

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How important is relationship chemistry? | dating advice – Harper’s Bazaar UK

Anyone whos been on their fair share of dates will know the feeling: youre getting along really well, theyre making you laugh, you can see theyre attractive. On paper, this should be a perfect match but theres just something missing. Some people call it chemistry, others love at first sight; Carrie Bradshaw memorably termed it the zsa zsa zsu. Were all conditioned to believe in that indefinable spark, which can be the make-or-break element of a successful relationship. But how important is that initial pull of cant-resist-you attraction?

Specific chemicals in the brain, like dopamine and vasopressin, create lust and make us focus on that one person: they make us crave them, almost obsess about them, says relationship psychologist

Andie and Ben fall in love in How To Lose A Guy In 10 Days, despite Andie doing her best to achieve the opposite

But for those worried that a partnership might be dead in the water if those first-date butterflies aren't there, theres good news: theres a big step between lust and love, and some of the most successful relationships do develop over time. The classic trope of friends to more-than-friends is more than just a storyline used in romantic comedies like When Harry Met Sally; in fact, friendship has been proven as one of the best foundations on which to build a relationship, and more than two-thirds of British couples start out as friends first. In these cases, attraction develops from forming an emotional bond first, says Gottlieb. This is crucial for relationship longevity.

Initial attraction is intoxicating, as well socially highly valued in a society that still promotes romantic ideals such as The One. However, real relationships are much more about communication and commitment than they are fireworks in the early days, says Gottlieb. Attraction is built from compatibility, and compatibility can be created, she explains. For example, even if partners dont have the same hobbies or interests, they can still bond over different interests by allowing each other to talk about their passions and by asking questions. Films like How To Lose A Guy In 10 Days and the newly released Anyone But You, starring Sydney Sweeney, are testament to how spending quality time with someone can make attraction blossom out of less than nothing as the old adage goes, theres a thin line between love and hate.

This knowledge that good relationships dont always come naturally isnt just helpful for single people on the lookout for love. Its also very important for couples who lose their initial spark, says Gottlieb. Couples need to prioritise alone time and schedule date nights, like they did at the beginning. A lot of attraction in dating is the result of novelty, and merely being intimate with a new person. There are many opportunities to create novelty in a long-term relationship, like going to new places together, trying a different hobby, or being more romantic with each other.

So the next time youre tempted to call it quits after a few dates, or even end a longer relationship that seems to have lost its excitement, remember that much of romantic love is, well, romanticised. Attraction on its own cant guarantee long-term relationship success, warns Gottlieb, so dont overrate passion at the expense of reliability, stability and genuine affection. Its about committing to that person, prioritising the relationship, and a willingness to put in the continued effort. While theres nothing quite like that first dopamine hit, real love is about celebrating what comes next in all its forms.

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Tom Hanks Talks Meg Ryan Chemistry, Reveals Why They Worked So Well Together – Just Jared

Tom Hanks is opening up about working with Meg Ryan!

The 67-year-old actor and the 62-year-old actress worked together on multiple projects, which includes Youve Got Mail, Sleepless in Seattle, Ithaca, Joe Versus the Volcano and Everything Is Copy.

For Youve Got Mails recent 25 year anniversary on December 18th, an old interview resurfaced where the actor talked about the chemistry between him and his co-star.

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Its just a natural thing, he told ET. Its like, why are we friends with the people that were friends with?

I must say, Meg and I are not real close pals, he shared at the time. We see each other every now and again. Its like, we dont hang out for coffee. But when we pick up, we just pick up where we left off and its an effortless thing that I dont think either one of us examines it too much because if we did, itd be a problem.

We dont plan. We just do it, he added.

If you missed it, Tom recently revealed what he would do if he went to outer space.

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Cowboy chemistry working on court – American Press | American Press – American Press

Published 8:25 pm Tuesday, December 26, 2023

Back before the season began, Will Wade said it would take time for this group of Cowboys to come together.

I think we will be a work in progress, was Wade. We will be a much better basketball team at the end of February than we are right now.

The first-year McNeese State head coach may have been sandbagging, or he may just have been telling the truth.

It doesnt matter now, for the fact is McNeese is off to a surprisingly strong 10-2 start as they get ready for their biggest test of the season, a trip to Michigan on Friday.

The Cowboys will take on the 6-6 Wolverines from the Big Ten as their last pre-conference game. It will also close out the 2023 portion of their schedule.

At first glance at the Cowboy schedule an 8-5 start would have been impressive, now it seems silly to even think that. McNeese has won five in a row and is 7-0 at home.

The Pokes are also 6-2 against other Mid-Majors, with wins on the road over Alabama-Birmingham and Virginia Commonwealth.

Their last two victories have come over the best from last years Sun Belt Conference, as they beat defending regular-season champ Southern Miss and then tournament winner Louisiana-Lafayette.

While unexpected to most, the Cowboys themselves are not surprised.

I think we should be 12-0, said center Antavion Collum.

When asked why these Cowboys are so good so fast Collum answered, We like playing together.

To a man, each player talks first about chemistry, which is a big surprise when you consider very few of them ever met before last summer let alone play together.

We all are here for a reason, said guard Shahada Wells. Coach Wade brought us together with the vision of doing something special this season. We are all here to win.

Not all of the bonding came on the court, in fact early in the process little did. It was more about getting to know each other as people and sharing their journeys to McNeese as much as anything.

We spent a lot of time doing things off the court together, said forward Christian Shumate. Coaches put us in a lot of tough spots and we went through them together.

Learning through adversity has been a key. So when they fell down to ULL by 13 with 11 minutes left and two starters were ejected there was no panic.

We just came together at that point, said Wells. We believe in each other. We knew we could get it done.

They also believe in each other, especially when it comes to scoring. When DJ Richards came off the bench to score a career-high 24 points against Southern Miss he quickly gave credit to the other Cowboys.

They got me the ball in good spots, said Richards. It was just my night. We have a lot of guys who can score, its just whose night it is.

And it is not just one offense that McNeese is connected either. The Pokes entered this week ranked third in the nation in team defense, allowing just 57.8 points a game.

That puts them in the company of some big programs like Houston, which is first, Virginia (2nd), and Iowa State (4th). Michigan, which averages 83.8 a game, good for 31st in the nation, will test that.

The Cowboys say they will be ready.

It will be a big challenge for us and we are looking forward to it, said Collum.

So are McNeese fans who want to see just how far chemistry can take this club.

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