Recently, an academic article published in Nature's Energy under the title of “Nature” has aroused great concern in the global energy community. A new research result from Stanford University brings new hope for large-scale energy storage. The school’s material is a new type of water battery—manganese hydrogen battery (Mn-H)—invented by the famous Chinese professor Cui Ying’s experimental group. It can be recharged more than 10,000 times and can achieve more than 10 years of stability. Its low cost and long lifespan. The potential performance of high energy density is expected to bring about tremendous changes in the field of large-scale energy storage.
According to the first author of the study, Dr. Chen Wei of the Stanford University School of Materials Science and Engineering introduced that the manganese hydrogen battery they invented uses a high surface area carbon as the positive current collector and a readily soluble manganese sulfate as the electrolyte. Hydrogen controlled by catalyst acts as a negative electrode. The battery is different from any previous water cell in terms of design, charge and discharge principle, test method and performance.
The results show that the manganese hydrogen battery has very good electrochemical performance, such as a stable discharge voltage of 1.3 volts, a high rate of discharge current 100mA/cm 2, More than 10,000 cycles of stabilization, and high mass energy density of 139Wh/kg and volume energy density of 210Wh/L. Moreover, the battery is easily scaled for large-scale energy storage.
Large-scale energy storage is the core technology for achieving the universal application of renewable energy. Existing large-scale energy storage technologies (such as pumped energy storage, compressed air energy storage) and various energy storage batteries (such as lithium-ion batteries, sodium-sulfur batteries, The flow batteries) all have different problems and are far from meeting the requirements for large-scale energy storage at low cost, safety, high energy density, and high stability. Cui Wei said: 'The invention of manganese hydrogen batteries will have a large-scale energy storage pattern. It will have an important impact and further alleviate the serious carbon emissions and air pollution brought about by traditional fossil fuels.
In the field of large-scale energy storage, in order to achieve this goal, scientists have developed a number of effective battery systems, including lithium-ion batteries, lead-acid batteries, flow batteries, sodium-sulfur batteries, liquid metal batteries and so on. However, these batteries do not have low energy density, short cycle life, high cost, harsh working conditions, and a long way to go in practical applications.
The main limiting factors for several battery systems include, in terms of energy density, the lead-acid battery is only 30-50 Wh/kg, and the fluid battery is also <50 Wh/l; 在循环寿命上, 铅酸电池<500次, 钠硫电池<1500次; 在封装成本上, 锂离子电池~250$/kWh, 铅酸电池~170$/kWh, 流体电池~450$/kWh; 在工作温度上, 钠硫电池要求300-350 ℃, 液态金属电池要求>450 °C.
According to the current U.S. Department of Energy’s recommendation, batteries that can be used for large-scale energy storage must meet the following conditions: The energy that can be charged and discharged in one hour is not less than 20 kilowatts, and at least 5 thousand charge and discharge can be supported, and the service life is Not less than 10 years. From a practical point of view, the price of a battery that satisfies the above conditions should not be higher than 2,000 US dollars, that is, the price for storing energy per kilowatt-hour should be less than 100 US dollars.
Professor Cui Wei proposed a new concept three years ago. Manganese and hydrogen were used as positive and negative electrodes respectively, and water was used as an electrolyte. Theoretically, it should be possible to realize large-scale energy storage in terms of energy density, service life, and price. The strict requirements. Under the guidance of Prof. Cui Wei, Chen Wei, a postdoctoral researcher of Chinese nationality at Stanford University, has conducted more than three years of exploration and experimental testing. Chen Wei said that the hydrogen battery device and various parameters After more than one thousand iterations of trial and error experiments, they finally obtained an optimized device and test conditions, which resulted in excellent battery performance. This newly developed battery can still not be apparent after 10,000 cycles of repeated charge and discharge. Decay, battery life has achieved an order of magnitude increase on the basis of the existing main energy storage methods.
Cui Wei Laboratory Postdoctoral Researcher Chen Wei Shows Battery Prototype
The prototype's new 3-nanometer-sized manganese-manganese-hydrogen battery currently generates only about 20 milliwatt-hours (mWh) of power, which is about the same as the energy level of the LED flash light hung on the key ring. Nevertheless, the experimenters believe this After the original technology is further improved, it will be expected to realize the industrialization of large-scale energy storage in the near future.
Cui Wei said that the technology is still in the experimental stage, and its research group is further optimizing the experimental prototype. These optimizations mainly focus on two aspects: first, to increase the energy density of the battery, and second, to reduce the cost of the battery. For example, in the earlier The use of platinum as a catalyst in the experiment is now considering the search for cheaper alternatives. After optimization, the research group will continue to conduct relevant pilot and large-scale tests. Professor Cui Wei has already obtained relevant patents and has set up the company. Industrialization.
According to Cui Wei, the global large-scale energy storage market has a scale of trillions of US dollars. Once the manganese-hydrogen battery can be industrialized and applied as expected, it will make the clean energy network more stable and bring about important social and economic development. Large-scale clean energy power plants, small residential areas, and household power consumption may all benefit from it. On the other hand, the industrialization and application of manganese-hydrogen batteries will also make it possible for the popularity of electric vehicles to be further approached. Stable power grids can provide this goal. possibility.
