Energy density 300Wh/kg batteries can be mass-produced

Lithium Grid News: Recently, there have been media reports that the electric car manufacturer Fisker has just applied for a solid-state battery patent, which increases the battery life of electric cars to an astonishing 804 kilometers. The time has also been reduced to one minute.

In China, power batteries, as one of the core components for the development of electric vehicles, have always been a hot spot in the field of battery research. In the new energy vehicle key special project of the national key research and development plan launched in 2016, the researcher Li Hong of the Clean Energy Laboratory of the Institute of Physics of the Chinese Academy of Sciences is responsible for the “research on new materials and new systems for long-lasting power lithium batteries”, which aims to develop high-energy High-density, high-safety lithium batteries to increase the range of electric vehicles, the project proposed to study three kinds of long-life power lithium batteries, lithium-ion batteries, semi-solid lithium-sulfur batteries, and solid-state lithium-air batteries, may become the future of China’s new energy vehicles. core.

Challenge the limit energy density of batteries

'Increase the energy density of power battery cells to more than 400Wh/kg, which will help significantly increase the driving range of electric vehicles. Take the BAIC EV200 as an example. For example, a 400Wh/kg battery cell is equivalent to a volumetric energy density above 800Wh/L. Keep the volume of the existing battery pack and the power consumption per ton of 100 kilometers unchanged, a single charge can not only last 620 kilometers, but also reduce costs and extend service life , To solve the current big difference between the performance of electric vehicles and fuel vehicles.' A few days ago, Li Hong said in an interview with a reporter from Science and Technology Daily.

As an important link in the overall layout of the national new energy vehicle power battery research and development, the task of this project is to develop new batteries with an energy density above 400Wh/kg at the forefront of the industry chain, which is the key to accumulating high energy density batteries Knowledge of basic scientific issues and key technologies, and provide important reference and guidance for enterprises to develop 300Wh/kg batteries simultaneously

The Ru0026D team of 'Research on New Materials and New Systems for Long-Endurance Power Lithium Batteries' is the task of challenging the extreme energy density of batteries in this project.

The energy density of mass-produced cells can be achieved at 300Wh/kg

The reporter found from the public Ru0026D plan declared by the company that there is a project team for the 300Wh/kg lithium-ion power battery route High nickel anode and nano silicon carbon anode were selected.

'From the recent progress, the energy density of mass-produced cells can reach 300Wh/kg technical indicators can be achieved.' Li Hong said.

In the recent research on new battery systems, the 'Long-Endurance Power Lithium Battery New Materials and New System Research' Ru0026D team used lithium-rich materials as the positive electrode and silicon-carbon material as the negative electrode. The energy density of the battery is up to The specific energy of the cell with lithium-rich material as the positive electrode and lithium metal as the negative electrode reaches 573Wh/kg; the specific energy of lithium-sulfur batteries reaches 600Wh/kg; the specific energy of primary lithium-air batteries reaches 780Wh/kg.

'In the development of high energy density batteries exceeding 300Wh/kg, the negative electrode containing lithium metal is an important common technology. Some research teams have proposed the use of solid electrolytes or mixed solid-liquid electrolytes to solve the problem of using or containing metal The main technical challenges faced by batteries with lithium negative electrodes.' Li Hong said.

In November 2013, the Chinese Academy of Sciences laid out the Chinese Academy of Sciences’ Strategic Leading Type A project. The project also supports the development of solid-state batteries. Three teams are involved in polymer, sulfide and in-situ solid-stateization. Progress has been made in technology.

The technical route is clear but still faces challenges

'In the soft-pack batteries of liquid electrolyte lithium-ion batteries currently developed and produced, the general liquid electrolyte weight percentage is 15%-25%. The negative electrode is carbon, silicon, etc. In the long run, it is necessary to develop an all-solid-state metal lithium battery in the future. The negative electrode contains lithium metal and the battery does not contain any liquid.' Li Hong said.

Although the technical route is relatively clear, it is currently facing great challenges. Li Hong said that from the perspective of the development of hybrid solid-liquid electrolyte batteries and all-solid-state metal lithium battery industries, it is necessary to focus on the development of solid electrolytes and metal lithium materials to solve the problems of interface ion and electron transport, as well as volume deformation and thermal stability. Most manufacturing equipment can be realized by using existing manufacturing equipment in the lithium-ion battery and primary metal lithium battery industries.

In addition, production environment control technologies such as drying rooms for mass production of lithium metal batteries have also been mastered. Despite the development of hybrid solid-liquid electrolyte batteries and all-solid-state metal lithium batteries, there are still many scientific and technological challenges, including challenges in cost control.

'As long as we thoroughly study the basic scientific problems clearly and come up with feasible and creative comprehensive solutions, even if there are difficulties, it is full of hope.' Li Hong said.