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Photo-rechargeable batteries (PRBs) benefit from their bifunctionality covering energy harvesting and storage. However, dim-light performances of the PRBs for indoor applications have not been reported. Herein, we present an external-power-free single-structured PRB named a dye-sensitized photo-rechargeable battery (DSPB) with an outstanding light-to-charge energy efficiency (ηoverall) of 11.5% under the dim light condition. This unprecedented ηoverall was attributed to the thermodynamically-favorable design of the DSPB that maximizes the working potential. At high-power irradiation, the kinetically-fast but thermodynamically-unfavorable iodine mediator (I−/I3−) showed the highest charge and discharge capacities even if its discharge voltage was lowest. Under dim-light for indoor applications, however, the thermodynamically-favorable but kinetically-slow copper complex mediator (Cu+/2+(dmp)2) showed energy density and efficiency superior to I−/I3− because its kinetics did not limit the harvesting capacity. The successful demonstration of the ability of the DSPB to operate a temperature-sensing IoT device only by indoor light opens the possibility of realizing indoor-light-harvesting PRBs.

We present a metal-ion-chelating organogel electrolyte, thermally gelated within cells, to solve the problems triggered by metal dissolution from cathodes of lithium ion batteries. The organogel significantly improved the capacity retention of lithium manganese oxide spinel during cycling. The organogel mitigated metal deposition on anodes by capturing metal ions (anode protection). Interestingly, the organogel inhibited metal dissolution by keeping dissolved metal ions highly concentrated around the cathode surface (cathode protection by Le Chatelier's principle).

Delithiation followed by lithiation of Li+-occupied (n-type) tetrahedral sites of cubic LiMn2O4 spinel (LMO) at ~4 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\bf{V}}}_{{{\bf{Li}}{\boldsymbol{/}}{\bf{Li}}}^{{\boldsymbol{+}}}}$$\end{document}VLi/Li+ (delivering ~100 mAh gLMO −1) has been used for energy storage by lithium ion batteries (LIBs). In this work, we utilized unoccupied (p-type) octahedral sites of LMO available for lithiation at ~3 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\bf{V}}}_{{{\bf{Li}}{\boldsymbol{/}}{\bf{Li}}}^{{\boldsymbol{+}}}}$$\end{document}VLi/Li+ (delivering additional ~100 mAh gLMO −1) that have never been used for LIBs in full-cell configuration. The whole capacity of amphi-redox LMO, including both oxidizable n-type and reducible p-type redox sites, at ~200 mAh gLMO −1 was realized by using the reactions both at 4 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\bf{V}}}_{{{\bf{Li}}{\boldsymbol{/}}{\bf{Li}}}^{{\boldsymbol{+}}}}$$\end{document}VLi/Li+ and 3 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\bf{V}}}_{{{\bf{Li}}{\boldsymbol{/}}{\bf{Li}}}^{{\boldsymbol{+}}}}$$\end{document}VLi/Li+. Durable reversibility of the 3 V reaction was achieved by graphene-wrapping LMO nanoparticles (LMO@Gn). Prelithiated graphite (LinC6, n

By coating nanoparticular lithium manganese oxide (LMO) spinel with a few layers of graphitic basal planes, the capacity of the material reached up to 220 mA h g(-1) at a cutoff voltage of 2.5 V. The graphitic layers 1) provided a facile electron-transfer highway without hindering ion access and, more interestingly, 2) stabilized the structural distortion at the 3 V region reaction. The gain was won by a simple method in which microsized LMO was ball-milled in the presence of graphite with high energy. Vibratory ball milling pulverized the LMO into the nanoscale, exfoliated graphite of less than 10 layers and combined them together with an extremely intimate contact. Ab initio calculations show that the intrinsically very low electrical conductivity of the tetragonal phase of the LMO is responsible for the poor electrochemical performance in the 3 V region and could be overcome by the graphitic skin strategy proposed.

Delithiation followed by lithiation of Li+-occupied (n-type) tetrahedral sites of cubic LiMn2O4 spinel (LMO) at ~4 $${{\bf{V}}}_{{{\bf{Li}}{\boldsymbol{/}}{\bf{Li}}}^{{\boldsymbol{+}}}}$$ V Li / Li + (delivering ~100 mAh gLMO−1) has been used for energy storage by lithium ion batteries (LIBs). In this work, we utilized unoccupied (p-type) octahedral sites of LMO available for lithiation at ~3 $${{\bf{V}}}_{{{\bf{Li}}{\boldsymbol{/}}{\bf{Li}}}^{{\boldsymbol{+}}}}$$ V Li / Li + (delivering additional ~100 mAh gLMO−1) that have never been used for LIBs in full-cell configuration. The whole capacity of amphi-redox LMO, including both oxidizable n-type and reducible p-type redox sites, at ~200 mAh gLMO−1 was realized by using the reactions both at 4 $${{\bf{V}}}_{{{\bf{Li}}{\boldsymbol{/}}{\bf{Li}}}^{{\boldsymbol{+}}}}$$ V Li / Li + and 3 $${{\bf{V}}}_{{{\bf{Li}}{\boldsymbol{/}}{\bf{Li}}}^{{\boldsymbol{+}}}}$$ V Li / Li + . Durable reversibility of the 3 V reaction was achieved by graphene-wrapping LMO nanoparticles (LMO@Gn). Prelithiated graphite (LinC6, n

A novel synthetic route was devised for 4-aminomethyl-3-Z-methoxyiminopyrrolidine methanesulfonate (AMPM), the key intermediate of gemifloxacin, based on chemoselective hydrogenation of the cyano group in 4-cyano-3-methoxyimino-1-(N-tert-butoxycarbonyl)pyrrolidine (CMBP) with minimum reduction of the methyloxime group employing (t-Boc)2O (BOC) as in situ protecting agent. Over Raney nickel or cobalt catalysts, without in situ BOC protection of amine, the side reaction to 4-aminomethyl-3-amino-1-(N-tert-butoxycarbonyl)pyrrolidine (AABP) was extensive by simultaneous hydrogenation of the methyloxime and cyano groups in CMBP, resulting in over-reduction of the desired intermediate, 4-aminomethyl-3-Z-methoxyimino 1-(N-tert-butoxycarbonyl)pyrrolidine (Z-AMBP) all the way to AABP. When in situ BOC protection was performed, the selectivity to the desired 4-(N-tert-butoxycarbonyl)aminomethyl-3-Z-methoxyimino-1-(N-tert-butoxycarbonyl)pyrrolidine (Z-BAMBP) rose to as high as 91% over Raney cobalt by suppressing the...

Chemoselective hydrogenation of 4-cyano-3-methoxyimino-1-(N-tert-butoxycarbonyl)pyrrolidine (CMBP) to 4-aminomethyl-3-Z-methoxyiminopyrrolidine methanesulfonate (AMPM), the key intermediate for gemifloxacin, was investigated over Pd catalysts with in situ acid protection. Addition of more than 1.6 equiv of acidic protons for CMBP was found to drastically elevate both the reaction rate and selectivity to 4-aminomethyl-3-Z-methoxyimino-1-(N-tert-butoxycarbonyl)pyrrolidine (Z-AMBP) over Pd catalyst with a complete suppression of the major side reaction to 4-cyano-3-amino-1-(N-tert-butoxycarbonyl)-3,4-pyrroline (CABP). Methanol as the organic solvent was found to increase the hydrogenation rate greatly compared to other solvents with a negligible decrease of selectivity. The leaching of Pd by acid and consequent accumulation of Pd ion in the reaction mixture was negligible in CMBP hydrogenation. The novel process of chemoselective CMBP hydrogenation in acidic media over Pd catalyst was thus much simpler yet m...

The capacity of nanoparticular LiMn2O4 (LMO) spinel can be improved up to 220 mAh/g at a cutoff voltage of 2.5 V by coating with a few layers of graphitic basal planes.

At present, the global market size of Li ion battery is dramatically increasing as its application in large scale system such as electric vehicle (EV) and energy storage system (ESS) expands intensely. Accordingly, the development of high-energy-density battery for their application is urgently needed. Today, energy density of Li ion battery largely depends on the specific capacity of cathode active material. The specific practical capacity of conventional cathode active materials such as LMO (Lithium Manganese Oxide Spinel, 4V region), LNMC (Lithium Nickel Manganese Cobalt Layered Oxide), and LFP (Lithium Iron Phosphate Olivine) is 100-170 mAh/g and the utilization of cathode active materials of even higher specific capacity is essential for the development of high-energy-density battery. Cathode active materials such as sulfur, oxygen, LMO (3+4V region) have theoretically very high specific capacity (270 – 3800 mAh/g), however, cannot be adopted in today’s Li ion battery industry because in their structure they do not possess lithium which is vital for electrochemical reaction in Li ion battery. To utilize these non-lithiated cathode active materials, additional lithium must be provided to the cell. Li half-cell where Li-foil is used as the anode in the cell could be a candidate, however, the Li dendrite growth problem which might lead to battery explosion should be precedently solved for practical application. More desirable and rather easily applicable solution is the prelithiation strategy in which anode or cathode is chemically lithiated (via lithium intercalation or alloying) by short-circuit reaction between the electrode and lithium source such as lithium foil, gas or powder. The prelithiation of anode is preferred because the cathode prelithiation might yield safety problem with excessive generation of heat of reaction. In this study, we propose an elegant prelithiation mechanism in graphite anode based on the results of electrochemical reaction and physico-chemical analyses. We demonstrate the prelithiation methodology that is directly applicable in practice with high prelithiation yield (efficiency) by controlling the relevant important variables. We also show that the developed prelithiation methodology can be applied for designing and operating full cell battery in which non- (or partially) lithiated LMO is adopted as cathode active material, which delivers ~200 mAh/g in 3+4V region with good cycle capability.