[energy storage technology] battery will save the world

Battery pioneer Whitingham said: "We only know the point of fur." With every effort made by the world to get rid of dependence on fossil fuels, batteries are likely to play an increasingly important role in our daily lives, with lithium batteries even more so.

　 Will batteries compete with petrol storage capacity in the future?

Three years ago, a science journalist, Farhad Manjoo, wrote an article to the American Internet magazine saying that "better batteries will save the world," while the subtitle "rebutted" the headline and said, "Too bad. It is impossible to do it." Although the automotive sector had just launched the Tesla S, Nissan LEAF, Chevrolet Volt, and released a large number of new hybrid and pure electric vehicles, from the box economy to two luxury hybrid Porsche.

The problems that Manjoo and others foresee are manifold: (1) car batteries are very expensive; (2) "energy density" (the amount of energy per unit of weight) seems to be far worse than gasoline; (3) there may be Danger - The key new material for lithium batteries is itself unstable, and it turns into powder in the air. One problem is that moisture may explode. Another problem is that this material is "insulated" and there is a possibility of "thermal breakdown" - rapid heating until ignition. Therefore, it is important that lithium be kept cool and dry.

But this last warning is precisely why lithium has become an attractive battery material: its dangerous energy is a huge advantage. Therefore, there is a silent lithium “sprint” in battery technology that has been and continues to be truly progressing. In recent years, due to the progress of batteries, fossil fuel vehicles have become "aesthetic" choices, not an economic necessity. Our urban power grid will become more complex and more predictable, reliable and economical.

Battery shock

Car batteries have changed from lead-acid to lithium-ion batteries, and nickel-cadmium flashlights have turned to handheld lithium-ion designs and batteries have become more efficient. Without a lithium-ion battery, there will almost certainly not be a current "mobile phone society." But approaching large-scale equipment such as vehicles and power stations to save our energy-consumed lives is full of winners such as the A123 system and its sponsors, Fiskar Karma, and Mo. Energy, Avestor, and Envia, which used to power General Motors, all lost millions and barely escaped the starting gates.

If anyone understands the challenges facing the battery revolution, it was this person who opened the battle for Exxon's lithium-ion battery in the late 1970s. It was M. Stanley Whittingham, who is now professor of chemistry at Binghamton University in northern New York, who predicted that "in a decade, every car will be a hybrid or electric vehicle."

He thinks there are many reasons for optimism. For example, a lot of resources are being invested in the technical challenges of making better batteries, from small, start-up computer companies and colleges to laboratories with well-equipped universities such as Harvard and Stanford, as well as major national laboratories in the United States, including Argonne. Lawrence Livermore and Sandia, as well as laboratories of major companies in Germany, the Netherlands, France, Japan, South Korea and China.

There is also a clear and urgent need to reduce the human emission of greenhouse gases. To replace fossil fuel energy, batteries will play a big role. Consumers clearly need renewable energy: sales of electric and hybrid vehicles are growing strongly, for example.

Better batteries offer two big prizes: First, affordable electric vehicles, which are the pillars of our future "mobile society"; followed by more flexible and decentralized power grids, as advanced fixed-cell batteries will be lower Prices maintain the electricity supply of our homes and factories.

Ending "mileage" anxiety

Initially proposed electric and hybrid cars are modest, with each driving range of 40 to 100 miles (excluding Tesla's high-priced electric vehicles rated at 265 miles), and only under ideal conditions. However, the second generation will soon reach 200 miles. The big Korean company LGChem supplies battery packs for the Chevrolet Volt and Ford Focus. It is reported that its updated lithium-ion design will drive these cars to 200 miles in 2016. Elon Musk, chairman and chief shareholder of Tesla Electric Vehicles, said that in August this year, his company was working on new batteries and it was necessary to increase the company's car mileage to 500 miles.

At the same time, the cost of the battery is declining. The research company Navigant pointed out that the price of laptop batteries was about US$1,000 per kilowatt-hour five years ago, and today “the price is close to US$250 per kilowatt-hour”. In July 2012, McKinsey ̇ Company reported that the price of advanced lithium-ion batteries for automobiles will be reduced from US$500 per kilowatt-hour in 2011 to US$160 per kilowatt-hour by 2025. Faving said that by 2020, the battery turnover will increase from today's 12 billion U.S. dollars to 75 billion U.S. dollars.

In the near future, battery cars will compete with gasoline-powered cars in terms of cost. Musk once said that the "Holy Grail" for battery power is $100 per kilometer-hour, which he expects to achieve within five to seven years. Tesla is working with Japan’s Matsushita to build a $5 billion “battery factory” in Spoks, Nevada, to create advanced batteries that are profitable on a scale. It is estimated that 500,000 battery packs will be produced each year, doubling the production of lithium-ion batteries worldwide.

Powerful BYD Qin

The battery has three basic components: two electrodes, an anode (negatively charged) and a cathode (positively charged), and an intermediate electrolyte (or commonly known as a battery fluid). What happens is a chemical reaction that closes the battery circuit (that is, turns on the light switch), electrons flow out of the anode, flow into the cathode through the electrolyte, and flow through the bulb to do work. The ion flow is in the opposite direction. The end result is a neutral condition where the battery is either discarded or recharged.

Most car batteries are now rechargeable, and some form of lithium is used as an electrode, cobalt or carbon is used as another electrode, and aluminum oxide is used as an electrolyte. But researchers are eager to see the next "big thing" is to explore the progress in battery technology from "crawling to sprint." Some major advances have shown hope of success. The energy density is about three to five times that of lithium ion. According to theoretical platinum standards, the fuel for cars even exceeds gasoline.

The most daring concept is Lithium-Air, which is replaced by traditional metals as the cathode and replaced with carbon. The battery is completely reformed and the oxygen atoms in the air are extracted to replace the oxides in the electrolyte. A team at the Massachusetts Institute of Technology (MIT) proposed a cathode made of nanowires. This is a very tiny structure built with a single atom and is actually made from a genetic variant virus. This is a very tricky material, and the laboratory design has proved to be twice as high as a typical lithium-ion battery and recharged faster.

With the advancement of battery chemistry, new materials like this will be the key. Graphene, which is ultra-thin (only as wide as the atom's width) single-layered carbon, was originally manufactured by two Russian scientists at the University of Manchester in 2003 (and was awarded the 2010 Nobel Prize in physics for this purpose) and developed as an electrode material. It is surprisingly strong, flexible and conductive. It can also be manufactured on a large scale and cheaply. Order online at $5 per gram. In the battery, it can drastically reduce the charging time and increase the energy storage capacity. Both XG Science and the SciNode system from Northwestern University and Argonne National Laboratory and headquartered in Michigan, United States, are working on graphene batteries. According to SciNode, its anode can provide three times or more of storage capacity than conventional carbon. According to China's Xinhua News Agency, Trass may also have a graphene project.

Stick to it, "to the dawn"

At the same time, we may be approaching the golden era of "fixed energy storage." There is no weight requirement for batteries that do not need to be moved, meaning that developers can use heavier, less unique, and cheaper materials. Such batteries provide backup power to make the grid more reliable and avoid peaks in peak energy costs, collecting non-peak-period renewable wind turbine and solar panel energy, and thus being inexpensive.

This design tends to reflect the work done on the car, but there are notable exceptions. AquionEnergy, headquartered in Pittsburgh, specializes in microgrids and partially complete power solutions, including solar, wind, or other renewable energy generation in remote areas. Its advanced battery cost is roughly equivalent to the old lead-acid battery, but its duration has doubled.

At MIT, Donald Sadoway and his team developed solid-state batteries that lasted a long time. According to them, it is easy to scale up. The material is common and inexpensive, but the design is completely innovative: it maintains a liquid state, accelerates electron and ion exchange, and the battery itself is kept at high temperatures, relies on tight insulation to maintain 350°F or more, but still produces energy with a 75% efficiency. , more than double the internal combustion engine. The AMBRI (original liquid metal battery company), based in Cambridge, is manufacturing the battery. It is said that the battery will continue for several decades and its performance will hardly decrease. Even if it is fully discharged, it is expected that the capacity of 10,000 cycles will still be 98%. This is a great success. Next year, the prototype was sent to four states for field testing.

The trick here is to compete with local power companies for the rate, and there is no advanced battery in this place. If you only do the “peak adjustment” and add extra power to the grid during the peak demand period, the rate may double or even triple (usually after noon) and the locality will pay in person soon.

Of course, there is still a long way to go. As battery pioneer Whitingham said, "We only know the point of fur." With every effort by the world to get rid of dependence on fossil fuels, batteries are likely to play an increasingly important role in our daily lives and may help to save the planet.