From the first generation of iPhone in 2007 to the end of 20 17, the use time of mobile phones only increased from 6 hours to more than 10 hours in ten years, and the battery industry lags far behind the development speed of other components on mobile phones. People have to always carry a heavy charging treasure with them. On the contrary, bright news about battery performance breakthrough frequently broke out in the field of scientific research: for example, a research team in a university achieved a battery breakthrough of "charging for 5 seconds and talking for two hours". Wait, so what should we think of these news? What changes can the scientific breakthroughs in these laboratories really bring to the electronic products in our daily life? What kind of battery technology is the new development of this satellite launch? ?
20 17 12 15 a new type of aluminum-graphene battery has been developed by the superb team of polymer science and engineering department of Zhejiang university. The related paper "Ultrafast All-weather Alumina-Graphene Battery with 250,000 Cycle Life" was published in scientific progress, and the first author was Dr. Hao Chen of the team. It is reported that this battery can work at MINUS 40 degrees Celsius to 120 degrees Celsius, which can be described as both high temperature and cold resistance. In the environment of -30℃, the new battery can achieve 1000 cycles, while in the environment of 100℃, it can achieve 45,000 cycles. This new battery is still flexible. After bending 10000 times, the capacity remains completely unchanged, and even if the battery cell touches the flame, it will not catch fire and explode. ?
The battery can work normally at high temperature. Two batteries in series can light a group of LED lights. ?
The anode of this battery is graphene film and the cathode is aluminum. Two batteries connected in series can light a group of LED lights. After testing, the specific capacity of graphene anode reaches 120mAh/g (mah/g). If one charge and discharge is taken as a cycle, the fast charge can be fully charged within 1. 1 sec, and it still has a reversible specific capacity of11mah/g. After 250,000 charge and discharge cycles, it can still maintain the capacity of 965,438+0% with almost no power loss. If the smart phone uses this battery, it can be used for nearly 70 years even if it is charged 10 times a day. ?
Is the new battery too powerful? The truth is ...?
After reading the above description, do you think this new battery is too powerful? ! I hope it can be mass-produced and used on our mobile phones as soon as possible, so that we can abandon the bulky charging treasure as soon as possible? But what is the real situation? Let's start with the origin of this invention. ?
On 20 15, the Dai Hongjie Research Group of Stanford University published their research results in the journal Nature. The anode is made of pyrolytic graphite foam at high temperature, and the aluminum ion battery with high specific capacity and long cycle is realized for the first time. Inspired by this, the research team of Professor Gao Chao of Zhejiang University tried to make electrodes for aluminum batteries with graphene films. ?
The aluminum ion battery developed by Stanford University and the negative electrode material of the battery. ?
"The performance of the battery depends on the state in which electrons and ions' run' between the anode and the cathode." Professor Gao Chao, the head of the research team, said that electrode materials should allow as many electrons and ions as possible to run smoothly or return to their positions quickly. If there are not enough roads or roads are crowded, performance will be affected. ?
After a year and a half of exploration and accumulation, the superb team put forward the design principle of "three highs and three continuity" for graphene cathode materials. "Three highs" refers to the high quality, high orientation and high porosity of microstructure; "Three continuity" refers to the existence of a continuous conductive network, a continuous ion transport channel and a continuous ion intercalation channel in the macro structure. In principle, this design makes the performance of aluminum-graphene battery take a big step forward. Before, the specific capacity of aluminum battery has been hovering around 60mAh/g, and the number of repeated charge and discharge is also within a thousand times. ?
"Taishan Beidou" in rechargeable battery industry-lithium ion battery?
At present, the most common commercial rechargeable battery is lithium-ion battery. The concept of lithium-ion battery was first put forward by Professor M.S.Whittingham of the United States in 1970. It was successfully developed by Yoshino Akira's team of Asahi Kasei Co., Ltd. in 199 1 year, and then commercialized by Sony Corporation in 1 year, with a total of * *. ?
Although its relatively stable performance can meet the current general use scenarios, lithium metal is an expensive and active rare metal. This means that the cost of lithium batteries will not be reduced to a very friendly level. At the same time, the safety risks of lithium batteries in many special occasions have to attract our attention. The relevant regulations on the carrying and consignment of lithium batteries in aviation industry prove the safety of lithium batteries in unconventional environment. ?
Subsequently, in order to reduce costs, scientists developed sodium batteries and aluminum batteries in the laboratory. Among them, aluminum is the most abundant metal element in the earth's crust, which is cheap and safe, and is an ideal negative electrode material for battery preparation. But for many years, the overall performance of aluminum batteries is still not as good as that of lithium-ion batteries and supercapacitors. The key problem of aluminum battery technology is to design a cathode material that can match aluminum and work efficiently. Only in this way can its excellent electrochemical performance really be brought into play. ?
Professor Yoshino akira and the first tubular lithium-ion battery prototype he designed for the experiment. ?
Professor Gao Chao pointed out that at present, there is still much room for improvement in the positive electrode specific capacity, output voltage and surface load of aluminum batteries, and the energy density is not enough to compete with lithium-ion batteries. In the future, it is necessary to further improve the energy density on the basis of maintaining high power density. In addition, the classical ionic liquid electrolyte is expensive at present, and if cheaper electrolyte can be found, the commercial prospect of aluminum ion batteries will be broader. Unless the cost is controlled at an acceptable level in the market, it is difficult to commercialize any new invention. ?
Large coater for lithium ion battery production workshop?
New Breakthrough of Green Battery: Does it take at least 8 to 10 years for commercialization?
In the past 20 years, as the core industry in the new energy industry, green batteries have been sought after by all walks of life, the government has increased investment, and the scientific research community is also enthusiastic. The papers published in the top international journals Nature and Science claim to have achieved a technological breakthrough. The essence of these papers is to announce to the world that they have developed a new battery material or discovered some key mechanism. ?
However, readers may not know that most of the battery prototypes in the laboratory are similar to the button cell used in watches. The commercial battery is a battery called 18650. It is the standard lithium-ion battery model set by Sony Corporation of Japan, the originator of lithium-ion battery, in order to save cost, where 18 means the diameter is 18mm, 65 means the length is 65mm, and 0 means the cylindrical battery. Whether it is a mobile power supply, a laptop or a battery in a Tesla electric sports car, it is this kind of battery. The production of this kind of battery cell needs the help of large-scale professional equipment to make and assemble in a dust-free and closed factory workshop. The laboratory obviously does not have this condition. Even if a cheap electrolyte can be found as an alternative material for ionic liquid electrolyte in the follow-up research, it will take at least 8 to 10 years to commercialize the battery prototype in the laboratory.
18650 battery and 2032 button cell?
Speaking of laboratories, in addition to universities and national laboratories, laboratories under enterprises also have a very important position. For example, the world-famous Xerox Center Laboratory in the United States in the last century was in the 1970s, and almost all the important technologies needed by the computer revolution were born in this laboratory. Some people say that at that time, half of the top computer talents in the world worked here. Do you think it's awesome? It is said that when Jobs visited Xerox Lab, he saw the graphical user interface and mouse for the first time and blushed with excitement. When he went back, he used it on an Apple computer. ?
In fact, the central laboratory affiliated to this enterprise is not just Xerox. More famous is Bell Laboratories, which belongs to AT & amp； Since the establishment of T Company, Bell Laboratories has obtained more than 27,000 invention patents, with an average of 4 patents per working day, and also won 8 Nobel Prizes, more than most countries. However, after so many years, only personal computers, laser printers, mice and graphical user interfaces are really used in our lives and remembered. ?
At present, the development of battery industry is more driven by micro-innovation within enterprises, such as the proportion of cathode materials, coating technology of materials, battery assembly technology and so on to improve the performance and safety of batteries. ?
To put it bluntly, for enterprise research, it is enough to know why, and it is not necessary to know why. It is important to know what to do and find a solution without having to study it clearly at the level of basic science. ?
Indeed, science and technology are two different things. Our primitive ancestors knew how to pry stones with sticks, which is technology; You don't have to wait until Archimedes put forward the lever principle, that's science. Watt improved the steam engine, as long as it can be used, it is technology; You don't have to figure out first, what is the principle of steam doing work? It's called science. ?
The purpose of scientific research is to serve the society, and every paper published in a journal has its significance. Periodicals stipulate that its significance must be clearly written in the abstract and conclusion of the paper. But these meanings are all expressed in strict professional terms, which is difficult for researchers who are not in this research field to understand, let alone ordinary non-scientific researchers. As for the eye-catching reports in the media, it is purely to attract attention. Next time you see this headline party news, consider it entertainment news.