This study investigates the impact of external pressure on various solid-state battery (SSB) materials, with a focus on electrode-level. Operando testing was conducted to monitor battery cells during cycling under a range of pressures, revealing how pressure influences electrochemical behavior and overall battery performance. A specialized setup was developed to enable real-time monitoring of battery cells under different pressure and temperature conditions.
With precise pressure control and measurement, the performance of lithium iron phosphate (LFP) electrodes using a polyethylene oxide (PEO) solid electrolyte was analyzed, generating valuable data to clarify underlying mechanisms. Early tests revealed notable sensitivity to pressure changes, particularly during charging and discharging. Further testing across a spectrum of pressure conditions provided comprehensive insights into material behavior in response to varying pressures.
This work offers significant insights into the fundamental mechanisms essential for the design and optimization of solid-state batteries. Notably, the relationship between pressure, contact area, and conductivity is critical; increased pressure can enhance the contact area between the electrodes and the electrolyte, often leading to improved ionic conductivity. However, too much pressure can lead to dendrites. Therefore a “pressure-balance” is vital for optimizing the performance of solid-state batteries.
Additionally, the potential of enhanced operando analysis techniques to deepen insights into SSB materials will be presented. To further this investigation, a gas connector was integrated into the setup to connect to mass spectrometry, enabling real-time analysis of gases produced during testing. This integration facilitates a comprehensive understanding of the chemical reactions and changes occurring at the material and electrode/electrolyte interfaces within SSBs under varying temperature and pressure conditions.
The findings of this research are crucial for advancing solid-state battery technology and facilitating innovations that lead to more efficient energy storage solutions. By examining the effects of pressure on battery materials, this study aims to enhance the design and implementation of solid-state batteries across various applications.