Radiolysis of Electrolytes in Batteries: A Quick and Efficient Screening Process for the Selection of Electrolyte‐Additive Formulations

Abstract

Understanding aging phenomena in batteries is crucial to the design of efficient, safe, and reliable energy storage devices as a part of the current green energy transition. Among the different aspects of a battery, the behavior of the electrolyte is a key parameter. Therefore, screening the aging characteristics of different electrolytes is of major interest. However, few screening studies exist because these are time‐consuming and require the monitoring of numerous charge and discharge cycles. It has been demonstrated here that radiation chemistry, i.e., the interaction between ionizing radiation and matter, is a valuable tool to screen the behavior of various electrolytes within a few hours. Indeed, the rapid radiolysis of electrolytes leads to the production of the same gases as produced by electrochemical cycling (i.e., H2, CO2), and the ranking of electrolytes by their H2 production yields similar performance ratings to those reported in the literature. Therefore, this direct comparison of electrolytes alone, lasting a few hours without any manufacturing operations such as the fabrication of electrochemical cells, demonstrates that controlled irradiation makes it possible to predict battery cycling behavior. Additionally, mechanisms involved in the degradation processes of different electrolytes are proposed.

Synergy between Cu and Co in a Layered Double Hydroxide Enables Close to 100% Nitrate-to-Ammonia Selectivity

“…Electrolytes exhibit a significant impact on the catalytic nitrate reduction efficiency. 67 The nitrate reduction onset potential of CuCoAl LDH/Vulcan in phosphate buffer (Figure S13a, green) shares a similar value to that observed in the Na 2 SO 4 solution (Figure S13a, blue: 0 V). Interestingly, the total cathodic current density observed in phosphate buffer is 18 mA cm −2 , which is 5 mA cm −2 less than that recorded in a Na 2 SO 4 solution (23 mA cm −2 ).…”

“…Next, the effect of the electrolyte on the nitrate reduction performance of CuCoAl LDH/Vulcan is explored (Figure S13). Electrolytes exhibit a significant impact on the catalytic nitrate reduction efficiency . The nitrate reduction onset potential of CuCoAl LDH/Vulcan in phosphate buffer (Figure S13a, green) shares a similar value to that observed in the Na 2 SO 4 solution (Figure S13a, blue: 0 V).…”

Selective Electroreduction of Nitrate into Ammonia on CuCoAl Layered Double Hydroxide for Sustainable Resourcification

“…Electrolytes exhibit a significant impact on the catalytic nitrate reduction efficiency. 76 The nitrate reduction onset potential of CuCoAl LDH/Vulcan in phosphate buffer (Fig. S8a green) is 0.13 V, which is 130 mV more positive relative to that observed in Na2SO4 solution (Fig.…”

In Situ Electron Paramagnetic Resonance Monitoring of Predegradation Radical Generation in a Lithium Electrolyte

“…Finally, it is fruitful to compare the capabilities of in situ EPR experiments with those of radiolysis, which is recently acknowledged as an analytical tool for accelerated ageing studies of electrolytes. , The radiolysis experiment is designed to mimic the electrolyte degradation occurring in real electrochemical cells by irradiation of electrolytes with energy sufficiently high to cause excitation and ionization of solvent molecules: M → M * , M •+ , e – . , In a mixture of cyclic and linear carbonates, the solvated electron decays ultrafast by attachment exclusively to an EC molecule, leading to the formation of EC anion radicals . The irradiation-generated ion-radicals undergo a series of reactions leading to the release preferentially of CO 2 and CO. , The in situ EPR experiment enables direct monitoring of anion radicals formed at the primary steps of the electrolyte oxidation due to a strong electron affinity of EC. (It is worth recalling that the microwave irradiation energy used in the EPR experiments permits splitting only the spin states of the paramagnetic species, but not to generate new radicals).…”