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Lithium batteries' big unanswered question
As the quiet whirr of electric vehicles gradually replaces the revs and noxious fumes of internal combustion engines, a number of changes are set to filter through our familiar world. The overpowering smell of gas stations will fade away into odourless charge stations where cars can re-juice their batteries as needed. Meanwhile, gas-powered generator sites that dot the horizon may be retrofitted to house massive batteries that could one day power entire cities with renewable energy.
This electrified future is much closer than you might think. General Motors announced earlier this year that it plans to stop selling gas-powered vehicles by 2035. Audi's goal is to stop producing them by 2033, and many other major auto companies are following suit. In fact, two-thirds of the world's passenger vehicle sales will be electric by 2040. And grid-scale systems the world over are growing rapidly thanks to advancing battery storage technology.
While this may sound like the ideal path to sustainable power and road travel, there's one big problem. Currently, lithium (Li) ion batteries are those typically used in EVs and the megabatteries used to store energy from renewables, and Li batteries are hard to recycle.
One reason is that the most widely used methods of recycling more traditional batteries, like lead-acid batteries, don't work well with Li batteries. The latter are typically larger, heavier, much more complex and even dangerous if taken apart wrong.
In your average battery recycling plant, battery parts are shredded down into a powder, and then that powder is either melted (pyrometallurgy) or dissolved in acid (hydrometallurgy). But Li batteries are made up of lots of different parts that could explode if they're not disassembled carefully. And even when Li batteries are broken down this way, the products aren't easy to reuse.
"The current method of simply shredding everything and trying to purify a complex mixture results in expensive processes with low value products," says Andrew Abbott, a physical chemist at the University of Leicester. As a result, it costs more to recycle them than to mine more lithium to make new ones. Also, since large scale, cheap ways to recycle Li batteries are lagging behind, only about 5% of Li batteries are recycled globally, meaning the majority are simply going to waste.
英国莱斯特大学（University of Leicester）的物理化学家安德鲁·阿伯特（Andrew Abbott）说，“目前的电池回收方法只是简单地将所有东西粉碎，然后再提取精炼复杂的混合物，这一回收过程成本高，但成功回收的产品价值却不高。”因此，回收锂电池的成本比开采更多金属锂来生产新锂电池的成本还要大。此外，由于大规模廉价回收锂电池的方式相当落后，全球只有大约5%的锂电池能够回收。换言之，大多数锂电池最后都成了垃圾废品。
But as demand for EVs escalates, as it's projected to, the impetus to recycle more of them is set to barrel through the battery and motor vehicle industry.
The current shortcomings in Li battery recycling isn't the only reason they are an environmental strain. Mining the various metals needed for Li batteries requires vast resources. It takes 500,000 gallons (2,273,000 litres) of water to mine one tonne of lithium. In Chile's Atacama Salt Flats, lithium mining has been linked to declining vegetation, hotter daytime temperatures and increasing drought conditions in national reserve areas. So even though EVs may help reduce carbon dioxide (CO2) emissions over their lifetime, the battery that powers them starts its life laden with a large environmental footprint.
锂电池的回收还不是造成环境压力的唯一原因。开采锂电池所需的各种金属需要大量资源。开采一吨锂需要消耗50万加仑的水。在智利的阿塔卡马盐滩（Atacama Salt Flats），因为开采锂矿，结果造成植被减少、白天气温升高，以及所在的国家保护区干旱日益严重等环保问题。因此，尽管电动汽车可以有助于减少二氧化碳的排放，但为其提供动力的电池一开始就对环境造成了很大的影响。
If the millions upon millions of Li batteries that will give out after around 10 years or so of use are recycled more efficiently, however, it will help neutralise all that energy expenditure. Several labs have been working on refining more efficient recycling methods so that, eventually, a standardised, eco-friendly way to recycle Li batteries will be ready to meet skyrocketing demand.
"We have to find ways to make it enter what we call a circular lifecycle, because the lithium and the cobalt and nickel take a lot of electricity and a lot of effort to be mined and refined and made into the batteries. We can no longer treat the batteries as disposable," says Shirley Meng, professor in energy technologies at the University of California, San Diego.
加州大学圣地亚哥分校（University of California, San Diego）的能源技术教授孟颖（Shirley Meng）说，“我们必须找到方法让锂电池进入我们所说的循环生命周期，因为锂、钴和镍需要大量的电力和大量的工作来开采、提炼和制造电池。我们不能再把锂电池当作一次性使用的产品。”
How to recycle Li batteries
A Li battery cell has a metal cathode, or positive electrode that collects electrons during the electrochemical reaction, made of lithium and some mix of elements that typically include cobalt, nickel, manganese and iron. It also has an anode, or the electrode that releases electrons to the external circuit, made of graphite, a separator and an electrolyte of some kind, which is the medium that transports the electrons between cathode and anode. The lithium ions travelling from the anode to the cathode form an electric current. The metals in the cathode are the most valuable parts of the battery, and these are what chemists focus on preserving and refurbishing when they dismantle an Li battery.
Meng says to think of an Li battery like a bookshelf with many layers, and the lithium ions rapidly move across each shelf, cycling back each time to the top shelf – a process called intercalation. After years and years, the bookshelf naturally starts to break down and collapse. So when chemists like Meng dismantle an Li battery, that's the sort of degradation they see in the structure and materials.
"We can actually find the mechanisms, [and] either using heat or some kind of chemical treatment method, we can put the bookshelf back [together]," says Meng. "So we can let those recycled and refurbished materials go back to the assembly line to the [Li battery] factories to be made into new batteries."
Improving Li battery recycling and ultimately making their parts reusable will reinfuse value into the Li batteries already out there. This is why scientists are advocating for the direct recycling process Meng describes – because it can give the most precious parts of Li batteries, like the cathode and anode, a second life. This could significantly offset the energy, waste and costs associated with manufacturing them.
But disassembling Li batteries is currently being done predominantly by hand in lab settings, which will need to change if direct recycling is to compete with more traditional recycling methods. "In the future, there will need to be more technology in disassembly," says Abbott. "If a battery is assembled using robots, it is logical that it needs to be disassembled in the same way."
Abbott's team at the Faraday Institution in the UK is investigating the robotic disassembly of Li batteries as part of the ReLib Project, which specialises in the recycling and reuse of Li batteries. The team has also found a way to achieve direct recycling of the anode and cathode using an ultrasonic probe, "like what the dentist uses to clean your teeth," he explains. "It focuses ultrasound on a surface which creates tiny bubbles that implode and blast the coating off the surface." This process avoids having to shred the battery parts, which can make recovering them exceedingly difficult.
阿伯特在英国法拉第研究所（Faraday Institution）的团队正在研发机器人拆卸锂电池的技术，这是专门研究锂电池的回收和再利用计划ReLib Project的一部分。这个研究团队还发现了一种利用超声波探头实现阳极端和阴极端直接回收的方法。他解释道，“就像牙医清洁牙齿一样，用超声波聚焦在正负两个电极板表面，使内层产生微小的气泡，然后发生内爆，将表面的涂层炸离。”这一过程维护了这两个重要部件的完整，避免了以往必须完全拆解因而使得回收大不易这个难题。
According to Abbott's team's research, this ultrasonic recycling method can process 100 times more material over the same period than the more traditional hydrometallurgy method. He says it can also be done for less than half the cost of creating a new battery from virgin material.
Abbott believes the process can easily be applied to scale, and used on larger grid-based batteries, because they typically have the same battery cell structure, they just contain more cells. However, the team is currently only applying it to production scrap, from which parts are easier to separate, because they're already free of their casings. The team's robotic dismantling tests are ramping up though. "We have a demonstrator unit that currently works on whole electrodes and we hope in the next 18 months to be able to showcase an automated process working in a production facility," says Abbott.
Some scientists are advocating for a move away from Li batteries in favour of ones that can be produced and broken down in more eco-friendly ways. Jodie Lutkenhaus, a professor of chemical engineering at Texas A&M University, has been working on a battery that is made of organic substances that can degrade on command.
一些科学家正在提倡抛弃锂电池，转为使用能够以较环保的方式生产和分解的电池。美国德州农工大学（Texas A&M University）的化学工程教授朱迪·卢肯豪斯（Jodie Lutkenhaus）一直在研究一种由有机物质制成可以按指令降解的电池。
"Many batteries today are not recycled because of the associated energy and labour cost," says Lutkenhaus. "Batteries that degrade on command may simplify or lower the barrier to recycling. Eventually, these degradation products could be reconstituted back into a fresh new battery, closing the materials life-cycle loop."
It's a fair argument considering that, even when a Li battery is dismantled and its parts are refurbished, there will still be some parts that can't be saved and become waste. A degradable battery like the one Lutkenhaus' team is working on could be a more sustainable power source.
Organic Radical Batteries (ORBs) have been around since the 2000s, and function with the help of organic materials that are synthesised to store and release electrons. "An Organic Radical Battery has two of these [materials], both acting as electrodes, that work in concert to store and release electrons, or energy, together," explains Lutkenhaus.
The team uses an acid to break their ORBs down into amino acids and other byproducts, however, conditions need to be just right for the parts to degrade properly. "Eventually we found that acid at elevated heat worked," says Lutkenhaus.
There are a number of challenges ahead for this degradable battery though. The materials needed to create it are expensive, and it has yet to provide the amount of power required for high-demand applications like EVs and power grids. But perhaps the greatest challenge degradable batteries like Lutkenhaus's face is competing with the already well-established Li battery.
The next step for scientists pushing direct recycling of Li batteries forward is working with battery manufacturers and recycling plants to streamline the process from build to breakdown.
"We are really encouraging all the battery cell manufacturers to barcode all the batteries so with robotic AI techniques we can easily sort out the batteries," says Meng. "It takes the entire field to cooperate with each other in order to make that happen."
Li batteries are used to power many different devices, from laptops to cars to power grids, and the chemical makeup differs depending on the purpose, sometimes significantly. This should be reflected in the way they're recycled. Scientists say battery recycling plants must separate the various Li batteries into separate streams, similar to how different types of plastic are sorted when recycled, in order for the process to be most efficient.
And even though they face an uphill battle, more sustainable batteries are slowly but surely coming onto the scene. "We can already see designs entering the market which make assembly and disassembly easier, and it is probable that this will be an important topic in future battery development," says Abbott.
On the production side, battery and car manufacturers are working on cutting down on the materials needed to build Li batteries to help reduce energy expenditure during mining and the waste each battery creates at the end of its life.
Electric car manufacturers have also begun to reuse and repurpose their own batteries in a number of different ways. For example, Nissan is refurbishing old Leaf car batteries and putting them in automated guided vehicles that bring parts to its factories.
Speed bumps ahead
The steadily increasing market demand for EVs already has companies across the automobile industry spending billions of dollars on increasing the sustainability of Li batteries. However, China is currently the largest producer of Li batteries by far, and subsequently ahead when it comes to recycling them.
The advent of a less complex, safer battery that is cheaper to make and easier to separate at the end of its life is the ultimate answer to the current sustainability problem with EVs. But until such a battery makes an appearance, standardising Li battery recycling is a significant move in the right direction.
And in about 2025, when millions of EV batteries reach the end of their initial life cycles, a streamlined recycling process will look much more appealing to economies the world over. So perhaps, by the time EVs become the predominant form of transport, there will be a good chance their batteries will be gearing up for a second life.
Maccabi hand Barcelona first defeat in basketball's Euro League******
JERUSALEM, Oct. 28 (Xinhua) -- Israeli champions Maccabi Tel Aviv notched an impressive 85-68 home win over Spanish champions FC Barcelona in the seventh round of basketball's Euro League on Thursday evening.
It was Barcelona's first loss in the tournament after six straight wins, while Maccabi now have five wins in seven games.
Maccabi dominated the first quarter, which ended 31-18, thanks to points by Derrick Williams, Scottie Wilbekin and Jalen Reynolds.
James Nunnally and Keenan Evans lifted the home team 45-24 ahead in the 26th minute and ended the half 56-36 up.
Nicola Mirotic led Barcelona to an 8-0 run early in the third quarter, and later the gap was cut to 65-54 at the end of the quarter with key points by Cory Higgins.
A strong team defense and significant offensive contribution by Wilbekin raised Maccabi to 74-58, and the Israeli side held on for a comfortable win.
Nunnally scored a team-high 17 points for Maccabi, with Wilbekin adding 16 more.
Higgins led the Barcelona scorers with a game-high 20 points. Mirotic added 17 points.
Barcelona will play their next game in Italy against Olimpia Milano on November 4, while Maccabi will face Saski Baskonia in Spain the following evening. Enditem
编辑 杨林鑫 校对 危卓
Panama, Peru to play January friendly******
PANAMA CITY, Dec. 3 (Xinhua) -- Panama and Peru will meet in an international friendly next month as both teams prepare to resume their 2022 FIFA World Cup qualifying campaigns.。
The clash will be played on January 16 at Estadio Nacional in Peruvian capital Lima and will have a 4pm kickoff, according to a statement published on the Panamanian football federation's official website on Friday.。
Panama, who are currently fourth in the North, Central America and Caribbean zone (CONCACAF) qualifying standings, will use the match to fine-tune ahead of a triple-header of qualifiers.。
The Central American team will face Costa Rica on January 27, Jamaica on January 30 and Mexico on February 2.。
Peru, fifth in South America's CONMEBOL qualifying tournament, will meet Colombia on January 27 and Ecuador on February 1.。
The top three teams in CONCACAF will earn an automatic World Cup berth while the fourth-ranked side will advance to an intercontinental playoff.。
In the CONMEBOL region, the top four sides will book a direct ticket to football's showpiece event in Qatar and the fifth team will clinch a playoff spot.。
Panama and Peru have not played each other since a friendly in August 2014, when the latter prevailed 3-1 in Lima. Enditem。