Piezoresistive Free-standing Microfiber Strain Sensor for High-resolution Battery Thickness Monitoring.

Area of Science:

• Materials Science
• Electrical Engineering
• Energy Storage

Background:

• Microfiber strain sensors are crucial for detecting mechanical deformations in space-limited applications.
• In situ monitoring of battery thickness requires high-resolution sensors with low detection limits.

Purpose of the Study:

• To develop a highly sensitive strain sensor for in situ lithium-ion battery thickness monitoring.
• To demonstrate the sensor's accuracy and applicability in real-time battery analysis.

Main Methods:

• Fabrication of a compliant fiber-shaped sensor using a wet-spinning method.
• Incorporation of microspherical core-shell conductive particles within an elastomer composite.
• Measurement of electrical resistance changes under applied strain.

Main Results:

• The sensor exhibits high strain sensitivity and an extremely low detection limit of 0.00005.
• Demonstrated high durability over 10,000 cycles.
• Successfully monitored real-time thickness changes of a lithium-ion battery pouch cell during charge and discharge.

Conclusions:

• The developed microfiber strain sensor is a promising, low-complexity solution for soft strain gauges.
• This technology enables accurate in situ monitoring of battery performance and integrity.
• The sensor's high sensitivity and durability make it suitable for advanced battery management systems.