Assessing the Thermal Safety of a Li Metal Solid-State Battery Material Set Using Differential Scanning Calorimetry

Nathan B Johnson; Bhuvsmita Bhargava; Jonathan Chang; Samaa Zaman; William Schubert; Paul Albertus

doi:10.1021/acsami.3c13344

Assessing the Thermal Safety of a Li Metal Solid-State Battery Material Set Using Differential Scanning Calorimetry

ACS Appl Mater Interfaces. 2023 Nov 22. doi: 10.1021/acsami.3c13344. Online ahead of print.

Authors

Nathan B Johnson¹, Bhuvsmita Bhargava¹, Jonathan Chang¹, Samaa Zaman¹, William Schubert², Paul Albertus¹

Affiliations

¹ Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland 20742, United States.
² Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States.

PMID: 37992236
DOI: 10.1021/acsami.3c13344

Abstract

At the earliest stage of battery development, differential scanning calorimetry (DSC) of a sample with all battery cell stack materials can provide quantitative data on the reaction thermochemistry. The resulting quantitative thermochemical map of expected reactions upon heating can then guide chemistry and component development toward improved cell safety. In this work, we construct Li_0.43CoO₂ + C + PVDF|Li_6.4La₃Zr_1.4Ta_0.6O₁₂|Li microcell DSC samples with capacity-matched electrodes and test to 500 °C. Notable observations are: (1) ∼74% of the O₂ released from the Li_0.43CoO₂ cathode reacts with C to form CO₂ rather than with molten Li to produce Li₂O, (2) PVDF pyrolysis (>400 °C) releases HF gas that exothermically reacts with Li to form LiF, and (3) reactions involving oxygen (e.g., CO₂ and Li₂O formation) account for ∼60% of the total heat released, and reactions involving HF (e.g., LiF formation) account for ∼36% of the total heat released.

Keywords: battery safety; ceramics; differential scanning calorimetry; electrode crosstalk; layered metal oxide; lithium metal; solid state; thermal runaway.