New breakthrough in lithium batteries!

Imagine if mobile phone batteries were not only safer and smaller in size, but also could last longer on a single charge!

Recently, the scientific research team of the Chinese Academy of Sciences Qingdao Institute of Bioenergy 

and Process has made new breakthroughs in the field of all solid state lithium batteries, 

which is expected to make the dream of miniaturization and long life of electronic equipment a reality. 

This achievement was published on July 31st in the international academic journal Nature Energy.

Most lithium-ion batteries used in mobile phones, computers, and other electronic devices store and release energy through liquid electrolytes. 

Now, scientists are researching a new type of battery - all solid state lithium battery. This type of battery uses solid electrolytes instead of liquids,

which makes them safer and less prone to leakage or fire like liquid electrolytes.

Although all solid state lithium batteries sound ideal, they also face some problems in research and development, 

mainly due to the difficulty in perfectly matching the chemical and physical properties of different materials inside the positive electrode of the battery,

 resulting in various interface problems that affect the energy density and service life of the battery. 

To solve this problem, the research team has developed a new material - homogenized positive electrode material (lithium titanium germanium phosphorus sulfur selenium).

Schematic diagram of microstructure evolution of composite positive electrode and homogenized positive electrode during charging process

Compared with traditional materials, this material has advantages such as high conductivity, high energy density, and long service life:

1. High conductivity: This new material combines high ionic conductivity and high electronic conductivity, 

which is more than 1000 times higher than traditional battery materials (layered oxide cathode materials). 

This means that even without relying on conductive additives, the positive electrode can smoothly complete the charging and discharging process, 

significantly improving the overall performance of the battery.

2. High discharge specific capacity: 

The discharge specific capacity of the new material is relatively high, reaching 250 milliampere hours per gram, 

exceeding the current use of high nickel positive electrode materials. 

Under the same weight or volume, batteries made of new materials can store more electrical energy. 

Not only can it allow the battery to run continuously for a longer period of time without frequent charging, 

but it can also improve the battery life; Moreover, reducing the size of the battery helps to design more compact devices.

3. Low volume change: During the charging and discharging process, the volume change of the new material is only 1.2%, 

far lower than the 50% of traditional materials (layered oxide cathode materials). 

This small volume change helps maintain the stability of the battery structure, thereby extending the battery's lifespan.

4. High energy density: The all solid state lithium battery using this new material has an energy density of 390 watt hours per kilogram, 

which is 1.3 times higher than the reported long cycle all solid state lithium batteries.

5. Long service life: All solid state lithium batteries using this material can achieve over 10000 cycles, 

and the battery can still maintain 80% of its initial capacity after 5000 cycles of charging. 

Can provide more sufficient power for a longer period of time.

This research provides technical support for the development of energy storage devices with high energy density and long service life, 

and offers safe and durable power sources for new energy vehicles, energy storage grids, deep-sea and deep space equipment. 

It is of great significance for the development of new energy storage systems.