Jean-Christophe Daigle

A novel and scalable synthesis route for DBUHFSI protic organic ionic plastic crystal , validated as a conductive matrix for all-solid-state batteries.

Correction for ‘High performance LiMnFePO₄/Li₄Ti₅O₁₂ full cells by functionalized polymeric additives’ by Jean-Christophe Daigle et al., Mater. Adv., 2021, 2, 253–260, https://doi.org/10.1039/D0MA00679C.

Herein, we report a novel class of additives based on functional polymers for electrode fabrication applied in the first fast charge–discharge and high-voltage LiMnFePO₄/Li₄Ti₅O₁₂batteries operating at 3.0 V.

In the battery industry, the performance of lithium-ion batteries operating at a high voltage is enhanced by utilizing functional additives in electrolytes to achieve higher energy densities and longer lifetimes. These additives chemically stabilize the electrolyte and aid in the formation of a stable cathode electrolyte interphase (CEI). In this paper, the investigation of oxidative potentials of more than 100 additives, using density functional theory calculations to determine the best candidates for CEI formation, is reported. The method was validated by comparing the calculated oxidation potentials and the experimental data obtained using linear sweep voltammetry based on the evaluation of 18 candidates. Further electrochemical studies (AC impedance and cycling stability) on six selected additives were conducted. Among the tested additives, the addition of quinacridone at 0.03% weight concentration resulted in the formation of a less resistive surface film on the cathode in Li/Ni_0.5Mn_0.3Co_0.2O₂ coin cells. Moreover, the capacity retention in Gr/Ni_0.5Mn_0.3Co_0.2O coin cells increased from 62% to 77% after 200 cycles at 1C and approximately 4.4 V. The derived results suggest that the combination of the oxidation potential prediction with impedance study could be used as a powerful tool to properly and efficiently select CEI-forming additive candidates for improved battery performance.

We report the analysis of comb-like polymers by solid-state NMR. The polymers were previously evaluated as solid-polymer-electrolytes (SPE) for lithium-polymer-metal batteries that have suitable ionic conductivity at 60 °C. We propose to develop a correlation between ¹³C solid-state NMR measurements and phase segregation. ¹³C solid-state NMR is a perfect tool for differentiating polymer phases with fast or slow motions. ⁷Li was used to monitor the motion of lithium ions in the polymer, and activation energies were calculated.

Lithium titanium oxide (Li₄Ti₅O₁₂)-based cells are a very promising battery technology for ultrafast-charge–discharge and long-cycle-life batteries. However, the surface reactivity of lithium titanium oxide in the presence of organic electrolytes continues to be a problem that may cause expansion of pouch cells. In this study, we report on the development of a simple and economical grafting method for forming hybrid polymer–Li₄Ti₁₅O₁₂ nanoparticles, which can be successfully applied in lithium-ion batteries. This method utilizes a low-cost and scalable hydrophobic polymer that is applicable in industrial processes. The hybrid materials demonstrated exceptional capability for preventing the degradation of cells in accelerated aging and operating over 150 cycles at 1C and 45 °C.