Towards higher specific energy, all-solid-state batteries are on the way

 

The solid-state battery track is crowded, and domestic and foreign companies have entered the game
 

Internationally, companies such as Toyota, Volkswagen, BMW, Hyundai Motor, Daimler, Hyundai, Honda, LG New Energy, and SK Innovation are vigorously developing solid-state batteries in order to seize the electric vehicle market
.
Among them, many companies have put forward clear time plans.
For example, Hyundai plans to trial production of electric vehicles equipped with solid-state batteries in 2025, partial mass production in 2027, and full mass production around 2030; Toyota plans to cooperate with Panasonic in 2025.
Cooperate to launch an electric vehicle using solid-state batteries; BMW plans to launch a prototype vehicle equipped with solid-state batteries by 2025, and start road testing of vehicles equipped with all-solid-state batteries by 2025, and achieve mass production by 2030; LG New Energy is expected to achieve mass production of all solid-state batteries in 2026; SK Innovation plans to use nickel-cobalt-manganese cathodes and silicon or graphite anodes in solid-state batteries by 2025
.

 

Domestic car companies and battery companies are not far behind.
CATL publicly stated in May 2021 that the company has been deeply involved in the field of solid-state batteries for many years, and its technical level is in the first echelon in China; BYD has started research on all-solid-state batteries since 2016.
, the number of patents ranked first in China
.
In addition to improving the energy density of solid-state batteries, BYD also focuses on improving the safety performance of solid-state batteries
.
Recently, BYD published a patent showing that BYD has developed a solid-state electrolyte, the solid-state electrolyte layer will not have the problem of cracking the protective layer, and even if a solid-state electrolyte particle fails to prevent lithium dendrite growth, other layers in the layer.
The particles also prevent the growth of lithium dendrites, which can improve the safety performance of the battery
.

 

　　All-solid-state battery technical barriers
 

　　An all-solid-state battery is a battery that uses solid electrodes and solid electrolytes
.
All-solid-state batteries can currently be divided into four categories: polymer all-solid-state batteries, thin-film all-solid-state batteries, sulfide all-solid-state batteries, and oxide all-solid-state batteries
.
At present, the development of these four all-solid-state batteries is in different predicaments: polymer all-solid-state batteries can only operate at high temperatures, and are not resistant to oxidation, and can only be matched with lithium iron phosphate cathodes, so the energy density is relatively high.
Low; thin-film all-solid-state batteries with large-capacity cells are difficult to manufacture, and the manufacturing cost is relatively high; the sulfide material of sulfide all-solid-state batteries is sensitive to air, high cost, and has poor solid-solid contact inside the positive electrode and negative electrode; oxidation All-solid-state (battery), the electrolyte ceramic sheet is easy to be brittle, the interface resistance is high, and it is difficult to prepare large-capacity cells
.

 

　　Despite facing many technical barriers, all-solid-state batteries have attracted increased investment from many car companies and battery manufacturers
.
In the long run, batteries with lower cost and longer battery life have become the demands of consumers, and the development of all-solid-state batteries is imperative
.

 

　　The development direction of batteries in the future: moving towards higher specific energy
 

　　The high cost of batteries and short driving range have always been the concerns of many consumers when purchasing electric vehicles, and they are also the main factors hindering the further development of electric vehicles
.
The pain points of electric vehicles actually guide the development direction of power batteries.
According to the current development trend, the future batteries will move towards higher specific energy, and the entire battery cell will move from liquid to safer mixed solid-liquid and full-scale.
Solid-state battery development
.

 

　　Original title: Towards higher specific energy, all-solid-state batteries are on the way