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this work presents an alternative method for fabricating Li-ion electrodes in which the use of aluminum/copper current collectors and expensive binders is avoided. Low-cost natural cellulose fibers with a 2-mm length are employed as binder and support for the electrode. The objective of this method is to eliminate the use of heavy and inactive current collector foils as substrates and to replace conventional costly binders with cellulose fibers. Moreover, no harmful solvents, such as N-methylpyrrolidone, are employed for film fabrication. Water-soluble carbons are also utilized to reduce the preparation time and to achieve a better repartition of carbon in the electrode, thus improving the electrochemical performance. flexible and resistant Lifepo 4 (Lfp), Li 4 ti 5 o 12 (Lto), organic 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA), and graphite electrodes are obtained with active mass loadings similar to those obtained by the current casting method. The initial discharge capacity of approximately 130 mAh•g −1 at 2 C is obtained for an LFP/LTO paper battery with an approximately 91.6% capacity retention after 1000 cycles. An all-organic prelithiated PTCDA/graphite cell without a transition metal is prepared and electrochemically tested. It is one of the first selfstanding batteries that is composed of organic redox active molecules and biodegradable components reported in literature. Over the past decade, flexible electronics 1,2 have undergone rapid developments in the fields of wearable 3,4 and implantable devices 5 , flexible displays 6 , and even flexible radio frequency identification tags 7. Li-ion battery is the most developed energy supply technology that satisfies high demands in energy, power, and long cycle life 8,9. For these reasons, flexible Li-ion batteries have gained particular attention as a future energy storage solution for lightweight and flexible devices 10,11. The widely used method for fabricating Li-ion electrodes (i.e., web-coating method), however, is unable to adequately satisfy these requirements 12. In fact, Cu and Al metal foils, which are generally used as current collector and support to spread the cathode or anode ink, lose contact with the active material during repeated bending 13. Moreover, the conventional method usually employs costly binders (such as polyvinylidene fluoride (PVDF)) that are dissolved in solvents (e.g., N-methyl-2-pyrrolidone (NMP)), which are characterized by high toxicity 14. Drying such electrodes also consumes a significant amount of energy because of their high boiling point (204.3 °C) and low vapor pressure (e.g., 1 mm Hg at 40 °C for NMP) 15. A greener process that employs sodium carboxymethyl cellulose as a low-cost binder and water as solvent has been reported 16-18 ; however, some major problems have to be resolved. Water-based electrodes exhibit agglomeration effects, poor ink homogeneity, and residual moisture after drying, which considerably reduce the cycle life of the battery 19. According to the cost modeling proposed by Wood et al. 20 ...

A LiCoPO4-based high-voltage lithium-ion battery was fabricated in the format of a 1.2 Ah pouch cell that exhibited a highly stable cycle life at a cut-off voltage of 4.9 V. The high-voltage stability was achieved using a Fe-Cr-Si multi-ion-substituted LiCoPO4 cathode and lithium bis(fluorosulfonyl)imide in 1-methyl-1-propylpyrrolidinium bis(fluorosulfony)imide as the electrolyte. Due to the improved electrochemical stability at high voltage, the cell exhibited a stable capacity retention of 91% after 290 cycles without any gas evolution related to electrolyte decomposition at high voltage. In addition to improved cycling stability, the nominal 5 V LiCoPO4 pouch cell also exhibited excellent safety performance during a nail penetration safety test compared with a state-of-the-art lithium ion battery. Meanwhile, the thermal stabilities of the 1.2 Ah pouch cell as well as the delithiated LiCoPO4 were also studied by accelerating rate calorimetry (ARC), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and in situ X-ray diffraction (XRD) analyses and reported.

All‐solid‐state batteries (ASSB) require stable and safe lithium (Li) metal anode, which needs surface preparation to increase lithium diffusion and impede the formation of dendrites. In this work, the formation of a thin LiZn layer on lithium metal using sputter deposition is reported. This method was selected due to the absence of solvents and by‐products generated during the modification, for its rapidity and because the formation of the alloy is performed in a clean and controlled atmosphere. Zinc has been chosen for its low cost and high Li+ ion diffusion coefficient of the corresponding LiZn alloy that is 1000 times higher than Li. Different parameters for the Zn deposition were investigated such as the distance between the Zn target and Li foil, the effect of substrate tilt and the direct current applied to the target. Electrochemical performance of LiFePO4/solid polymer electrolyte/Li ASSB demonstrated the superiority of the LiZn anodes and the clear influence of deposition parameters on the durability and performance at high C‐rates. Scanning electron microscopy images of the cross‐sectional view of LFP/SPE/Li stackings extracted from pouch cells after cycling showed an evident migration of Zn into the bulk Li metal anode as well as the formation of AlZn nanoparticles.

Significant electrochemical performance improvement of symmetric Li/Li polymer cells at C/4 by using ceramic-rich coated lithium anodes.