Evaluation of Commercial Li-Ion 2032 Coin Cells for Non-Ambient Temperature Applications

Rechargeable Li-ion 2032 coin cells are widely used in consumer electronics and fundamental battery research, yet their behavior under non-ambient conditions remains insuciently characterized. In this work, five commercial LIR2032-type cells, including standard and high-capacity variants from multiple manufacturers, were evaluated over 100 galvanostatic cycles at 0C, 24C, and 60C. Ex situ X-ray difraction confirmed graphite anodes and LiCoO2 cathodes for all cells. Galvanostatic cycling revealed that room-temperature operation provides the most stable per- formance, while low-temperature cycling limits accessible capacity through kinetic constraints and high-temperature cycling accelerates degradation despite enhanced initial utilization. Differential capacity (dQ/dV) analysis identified consistent phase-transition signatures and degradation modes, including initial ohmic resistance reduction followed by cathode-dominated aging. Electrochemical impedance spectroscopy combined with distribution of relaxation times analysis enabled separation of bulk, interfacial, charge-transfer, and diffusion processes, revealing an extended solid–electrolyte interphase self-optimization period and atypical anode impedance evolution correlated with transient capacity increases. These results provide a comparative framework for diagnosing temperature-dependent degradation in commercial coin cells.