Lithium-ion battery structure that self-heats at low temperatures

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium-ion batteries experience significant power degradation below 0°C, hindering applications in cold climates.
• Current solutions involve external heating or electrolyte additives, which have limitations.
• Low-temperature power loss impacts electric vehicle range, charging, and performance.

Purpose of the Study:

• To introduce a novel lithium-ion battery structure, the 'all-climate battery' cell.
• To demonstrate a self-heating mechanism that operates without external devices or additives.
• To enhance low-temperature electrochemical performance for high discharge and charge power.

Main Methods:

• Development of a unique lithium-ion battery cell architecture enabling internal self-heating.
• Testing of the self-heating mechanism's speed and energy consumption at sub-zero temperatures.
• Evaluation of the self-heated cell's power output and comparison with conventional lithium-ion cells.

Main Results:

• The 'all-climate battery' self-heats to 0°C within 20-30 seconds at -20°C to -30°C, using minimal capacity (3.8-5.5%).
• At -30°C, the self-heated cell delivers 6.4-12.3 times more power (1,061/1,425 W/kg) than state-of-the-art cells.
• The self-heating mechanism creates a favorable electrochemical interface for improved power.

Conclusions:

• The 'all-climate battery' effectively mitigates low-temperature power loss in lithium-ion cells.
• This technology can enable efficient engine stop-start systems, potentially saving fuel in vehicles.
• Applications extend to plug-in electric vehicles, robotics, and space exploration due to efficient self-heating.