APPLICATIONS OF TECHNOLOGY:
- Portable electronics
- Electric and hybrid vehicles
- Load leveling for power grids
- Enables better cycling efficiency, performance, and lifetime of Li-ion batteries
- Electrolytes remain stable >4.2 volts
- Improved safety
- Low cost
Berkeley Lab researchers led by Robert Kostecki have developed a technology for extending the life and improving the electrochemical performance and safety of high-energy lithium ion batteries through thermal treatment of the carbon black additive used to make composite electrodes.
In the Berkeley Lab approach, heat treatment of carbon black in a CO2 atmosphere removes surface impurities and sp-coordinated carbon atoms, which reduces the surface reactivity of the carbon additive under the operating conditions of a high voltage Li-ion cathode. The thermal treatment process decreases surface reactivity of the carbon black and extends the electrochemical stability window of conventional electrolytes, enabling use of novel, high voltage cathode materials. By inhibiting electrolyte oxidation on composite high voltage cathodes, Li-ion batteries built with modified carbon black additives exhibit improved cyclability, longer life, and operate with lower risk of cell damage or dangerous thermal runaway conditions.
The CO2 heat treatment process can be easily integrated into the carbon black synthesis process. Importantly, the modified carbon black can be used to manufacture composite electrodes using standard, scalable, lithium ion battery electrode fabrication methods.
Carbon black, commonly used as a conducting additive in lithium ion battery composite cathodes, can be highly reactive toward organic electrolytes, particularly at voltages higher than 4.2 V. Electrolyte oxidation can occur not only on the surface of the active material, but also on the surface of carbon. This instability affects battery’s cycling efficiency, energy storage capacity, cycling life, safety and cost.
DEVELOPMENT STAGE: Bench scale prototype
STATUS: Patent pending. Available for licensing or collaborative research.
SEE THESE OTHER BERKELEY LAB TECHNOLOGIES IN THIS FIELD:
REFERENCE NUMBER: IB-3193