From an Enhanced Understanding to Commercially Viable Electrodes: The Case of PTCLi₄ as Sustainable Organic Lithium‐Ion Anode Material

Abstract

for tomorrow's society. [1][2][3] For this purpose, however, the battery technology itself must become sustainable as well. A great step forward toward this highly desirable goal would be the replacement of currently utilized inorganic electrode compounds, which commonly require energy-intensive synthesis methods and relatively rare metals, by eco-efficient organic lithium storage materials, ideally using biomass as precursors. [4] While this general concept has been proposed as early as the development of the first commercial lithium-based battery, [5] it was basically the work of Armand, Poizot, Tarascon, and co-workers, [6][7][8] reporting the reversible electrochemical activity of conjugated carbonyl functionalities, which triggered a continuously rising interest in studying macromolecular and polymeric compounds as lithium, and-due to their great versatility-sodium battery electrode materials. [9][10][11] In addition to their high availability, low cost, and environmental friendliness, organic active materials offer the distinguished advantage of tailorable lithium reaction potentials and capacities by carefully designing the molecular architecture. [9][10][11][12][13] In particular, the presence of planarly delocalized π-electrons, following the incorporation of phenyl groups in the units interconnecting the electrochemically active carbonyl functions, results in improved achievable capacities and Organic active materials are currently considered to be the most promising technology for the realization of fully sustainable secondary batteries. However, the understanding of the underlying reaction mechanisms is still at its beginning. In this paper, an in-depth investigation of tetra-lithium perylene-3,4,9,10-tetracarboxylate as a lithium-ion anode model compound is presented, which can be easily synthesized from commercially available 3,4,9,10-perylene-tetracarboxylic-dianhydride. The results reveal that the lithium uptake is limited to two lithium ions per molecule along a two-phase equilibrium potential within an operational voltage range down to 0.1 V. Below the corresponding potential plateau at 1.1 V the origin of the extra capacity is solely related to the presence of large amounts of conductive carbon. Based on these findings, optimized electrode composites with increased active material ratios of up to 95 wt% and a total active material mass loading of about 12.0 mg cm −2 , that is, remarkably augmented areal capacities (≈1.2 mAh cm −2 ), using percolating carbon nanotubes as electron conductor and environment-friendly, fluorine-free aqueous binders, are developed. In addition to the more than tenfold increase in areal capacity, these optimized electrode compositions show enhanced first cycle coulombic efficiencies, thus providing a great leap forward toward their commercial exploitation.

Sustainable Energy Storage: Recent Trends and Developments toward Fully Organic Batteries

“…In contrast, Iordache et al. demonstrated a hybrid lithium‐ion cell using perylene‐3,4,9,10‐tetracarboxylate as active electrode material, which featured a stable voltage of 1.2 V and an initial capacity of 120 mAh g −1 , losing 25 % over the first 200 cycles . Consequently, the material was also used in a fully organic cell, using a hexyl‐linked perylene diimide polymer as second electrode material .…”

“…[102] In contrast,I ordache et al demonstrated ah ybrid lithium-ion cell using perylene-3,4,9,10-tetracarboxylatea sa ctivee lectrode material, which featured as table voltage of 1.2 Vand an initial capacityo f1 20 mAh g À1 ,l osing 25 %o ver the first 200 cycles. [103] Consequently,t he material was also used in a fully organic cell, using ah exyl-linked perylene diimidep olymer as second electrode material. [76] The cell possessed a slightly decreasing discharge voltage with an average at 1.1 V and ac apacity of 75 mAhg À1 ,w hichs howed ar easonable drop to 80 %w ithin the first 200 cycles (Figure14).…”

Glycination: A Simple Strategy to Enhance the Cycling Performance of Perylene Dianhydride for Secondary Li–Ion Battery Applications

“…Moreover, the electronic conductivity of perylene tetracarboxylic dianhydride (PTCDA) was further improved by adding conductive additives such as CNTs and reduced graphene oxide (rGO) to achieve higher current densities ,. In addition, lithium salt of perylene tetracarboxylate (Li 4 ‐PTC) has also been reported as anode material for LIBs, which exhibited well‐defined potential plateaus at 1.2 V vs. (Li/Li + ) with negligible polarization and good cyclability ,,. Taking advantage of high potentials of perylene polyimides (cathode) and low potential of its carboxylate derivative (anode), Iordache and coworkers reported a perylene‐based all organic lithium‐ion battery with good cyclability .…”

“…In addition, lithium salt of perylene tetracarboxylate (Li 4 ‐PTC) has also been reported as anode material for LIBs, which exhibited well‐defined potential plateaus at 1.2 V vs. (Li/Li + ) with negligible polarization and good cyclability ,,. Taking advantage of high potentials of perylene polyimides (cathode) and low potential of its carboxylate derivative (anode), Iordache and coworkers reported a perylene‐based all organic lithium‐ion battery with good cyclability . Though polymerization of aromatic diimides mitigates its dissolution in the electrolyte effectively, it still causes poor cyclability particularly, at low current densities, possibly due to fragmentation of polyimides into monomers via rupturing of N−N bonds in the polymer chain during electrochemical lithiation/delithiation process .…”

Tuning the Electrochemical Properties of Organic Battery Cathode Materials: Insights from Evolutionary Algorithm DFT Calculations

“…The latter problem is mainly due to the fact that the functional redox groups need to be connected to conjugated organic cores, which in turn are not redox active but contributes to weight and volume. For SOMs, significant improvement on cycling stability has been achieved with the development of carboxylates following the pioneer work of Tarascon and co‐workers . Special focus has been given to dilithium terephthalate (Li 2 TP), because it can be straightforwardly obtained by recycling polyethylene terephthalate (PET) plastic and can deliver a reversible capacity of 300 mAh g −1 .…”