Which have advantageous solid-state batteries or liquid batteries?

Which have advantageous solid-state batteries or liquid batteries?

As China has become the world's largest electric vehicle market, power battery industry has also developed rapidly. The production and sales of lithium batteries are increasing year by year.

However, as the industrialization of lithium batteries gradually matures, the state subsidizes the subsidies for new energy vehicles and batteries until the policy is abolished. The development of the current industry and the implementation of policies put new demands on the energy density of batteries. The development trend of power batteries is moving toward a safer and more energy-intensive side.

Solid-state lithium metal batteries are the best solution for energy density?

"Solid lithium metal batteries are the best solution for energy density." Hu Qichao, founder and CEO of Massachusetts Solid Energy Company, believes that from the development trend of current lithium battery technology, from the perspective of route development, solid-state lithium metal batteries are the optimal solution for energy density. The state of the current battery is moving from a liquid to a solid state in a safer direction.

So, which one is more advantageous than solid-state batteries and liquid batteries?

The traditional liquid lithium battery is aptly called "rocking type battery". The two ends of the rocking chair are the positive and negative poles of the battery, and the middle is electrolyte (liquid). Lithium ion is like an excellent athlete. It runs back and forth between the two ends of the rocking chair. During the movement of lithium ions from the positive pole to the negative pole to the positive pole, the charging and discharging process of the battery is completed. The principle of a solid-state battery is the same, except that its electrolyte is solid, and its density and structure allow more charged ions to accumulate at one end, conducting more current, thereby increasing battery capacity.

Therefore, with the same amount of electricity, the solid-state battery will become smaller. Not only that, because there is no electrolyte in solid-state batteries, sealing becomes easier. When used on large equipment such as automobiles, there is no need to add additional cooling tubes, electronic controls, etc., while saving costs and reducing weight. In addition, in terms of energy density, the technology of lithium batteries is developing from a higher energy density of lithium ions to lithium metal.

Hu Qichao introduced that the solid-state lithium metal battery he and the team are currently working on is understood in an analogous way, putting the current universal smartphone battery and the battery together. Solid-state lithium metal batteries are half the size of the former, but the amount of electricity stored is the same. Moreover, the battery is lighter in weight and lower in battery cost. At present, pure solid metal batteries are generally used in relatively high-end fields such as military,special and drone.

Breakthrough in the basic research of controlling lithium dendrite formation, lithium metal industrialization is waiting

In the battery market, lithium batteries quickly occupy the market by virtue of their safety, long service life, low maintenance cost, light weight, complete charge and discharge, and no memory effect.

However, during the use of the lithium battery, an internal irreversible electrochemical reaction such as decomposition of the electrolyte, deactivation of the active material, collapse of the positive and negative structures, and reduction in the number of lithium ion insertion and deintercalation may occur, resulting in a decrease in capacity. Especially in the current requirements of fast charging, the higher the charging and discharging voltage and the higher the temperature, the faster the capacity of the lithium battery decreases, and the battery life decay is a challenge in the industry.

"Lithium metal can exceed the graphite and silicon carbon negative electrode in performance, and can be made smaller." Hu Qichao introduced that the control of lithium dendrite technology, based on solid electrolyte solution can solve the problem of life decay to a large extent. . However, at present, the cost of solid-state lithium metal batteries is relatively high, and it is more suitable for applications that are lighter and less cost-conscious.

In fact, the United States Massachusetts Solid Energy Company is currently one of the few battery companies in the world that can achieve a power battery energy density of more than 500Wh, and is currently the only battery factory to achieve mass production supply.

It is understood that in 2012, Hu Qichao founded SolidEnergy after graduating from MIT, and began the research of secondary lithium metal batteries, which increased the energy density to twice that of traditional lithium-ion batteries. It has raised more than $50 million in well-known venture capital institutions in the US and Asia. In the first half of 2012, Hu Qichao won the Clean Energy Award from the US Department of Energy and the runner-up in the National Clean Energy Business Plan Competition. In the same year, it was also selected by Forbes magazine as one of the 30 outstanding scientists under the age of 30.

In 2017, SolidEnergy released the first generation of Hermes (High Energy Rechargeable MetalCellsforSpace), the world's lightest secondary battery with an energy density of 480Wh/Kg, which may trigger a new round of battery revolution in ground and air transportation. Hu Qichao said that in the future, SolidEnergy is ready to put this technology into space, defense, consumer-grade drones, smart phones, wearable equipment and electric vehicles. A new lithium metal industrialization model are coming.

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