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  • A Non-Flammable High-Voltage 4.7 V Anode-Free Lithium Battery. Advanced materials (Deerfield Beach, Fla.) Liang, P., Sun, H., Huang, C., Zhu, G., Tai, H., Li, J., Wang, F., Wang, Y., Huang, C., Jiang, S., Lin, M., Li, Y., Hwang, B., Wang, C., Dai, H. 2022: e2207361


    Anode-free lithium metal batteries employ in-situ lithium plated current collectors as negative electrodes to afford optimal mass and volumetric energy densities. The main challenges to such batteries include their poor cycling stability and safety issues of flammable organic electrolytes. Here, we report a high-voltage 4.7V anode-free lithium metal battery using a Cu foil coated with a layer ( 950nm) of silicon-polyacrylonitrile (Si-PAN, 25.5mug cm-2 ) as the negative electrode, a high-voltage cobalt-free LiNi0.5 Mn1.5 O4 (LNMO) as the positive electrode and a safe, non-flammable ionic liquid electrolyte comprised of 4.5M lithium bis(fluorosulfonyl)imide (LiFSI) salt in N-methyl-N-propyl pyrrolidiniumbis(fluorosulfonyl)imide (Py13 FSI) with 1 wt% lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as additive. The Si-PAN coating was found to seed the growth of lithium during charging, and reversibly expand/shrink during lithium plating/stripping over battery cycling. The wide voltage-window electrolyte containing a high concentration of FSI- and TFSI- facilitated the formation of stable solid-electrolyte interphase, affording a 4.7V anode-free Cu@Si-PAN/LiNi0.5 Mn1.5 O4 battery with a reversible specific capacity of 120 mAh g-1 and high cycling stability (80% capacity retention after 120 cycles). These results represent the first anode-free Li battery with a high 4.7V discharge voltage and high safety. This article is protected by copyright. All rights reserved.

    View details for DOI 10.1002/adma.202207361

    View details for PubMedID 36193778

  • High-precision tumor resection down to few-cell level guided by NIR-IIb molecular fluorescence imaging. Proceedings of the National Academy of Sciences of the United States of America Wang, F., Qu, L., Ren, F., Baghdasaryan, A., Jiang, Y., Hsu, R., Liang, P., Li, J., Zhu, G., Ma, Z., Dai, H. 2022; 119 (15): e2123111119


    SignificanceSurgical removal of tumors has been performed to combat cancer for over a century by surgeons relying on visual inspection and experience to identify margins between malignant and healthy tissues. Herein, we present a rare-earth down-conversion nanoparticle-anti-CD105 conjugate for cancer targeting and a handheld imager capable of concurrent photographic imaging and fluorescence/luminescence imaging. An unprecedented tumor-to-muscle ratio was achieved by near-infrared-IIb (NIR-IIb, 1,500 to 1,700 nm) imaging during surgery, 100 times higher than previous organic dyes for unambiguous determination of tumor margin. The sensitivity/biocompatibility/safety of the probes and instrumentation developed here open a paradigm of imaging-guided surgery at the single-cell level, meeting all major requirements for clinical translation to combat cancer and save human lives.

    View details for DOI 10.1073/pnas.2123111119

    View details for PubMedID 35380898

  • Highly elastic and low resistance deformable current collectors for safe and high-performance silicon and metallic lithium anodes JOURNAL OF POWER SOURCES Liang, P., Huang, Z., Chen, L., Shao, G., Wang, H., Sun, H., Wang, C. 2021; 511
  • Rechargeable Na/Cl2 and Li/Cl2 batteries. Nature Zhu, G., Tian, X., Tai, H., Li, Y., Li, J., Sun, H., Liang, P., Angell, M., Huang, C., Ku, C., Hung, W., Jiang, S., Meng, Y., Chen, H., Lin, M., Hwang, B., Dai, H. 2021; 596 (7873): 525-530


    Lithium-ion batteries (LIBs) are widely used in applications ranging from electric vehicles to wearable devices. Before the invention of secondary LIBs, the primary lithium-thionyl chloride (Li-SOCl2) battery was developed in the 1970s using SOCl2 as the catholyte, lithium metal as the anode and amorphous carbon as the cathode1-7. This battery discharges by lithium oxidation and catholyte reduction to sulfur, sulfur dioxide and lithium chloride, is well known for its high energy density and is widely used in real-world applications; however, it has not been made rechargeable since its invention8-13. Here we show that with a highly microporous carbon positive electrode, a starting electrolyte composed of aluminium chloride in SOCl2 with fluoride-based additives, and either sodium or lithium as the negative electrode, we can produce a rechargeable Na/Cl2 or Li/Cl2 battery operating via redox between mainly Cl2/Cl- in the micropores of carbon and Na/Na+ or Li/Li+ redox on the sodium or lithium metal. The reversible Cl2/NaCl or Cl2/LiCl redox in the microporous carbon affords rechargeability at the positive electrodeside and the thin alkali-fluoride-doped alkali-chloride solid electrolyte interfacestabilizesthe negative electrode, both are critical to secondary alkali-metal/Cl2 batteries.

    View details for DOI 10.1038/s41586-021-03757-z

    View details for PubMedID 34433941

  • In Situ Electrode Stress Monitoring: An Effective Approach to Study the Electrochemical Behavior of a Lithium Metal Anode ACS APPLIED ENERGY MATERIALS Liang, P., Shao, G., Wang, H., Wang, C. 2021; 4 (4): 3993-4001
  • A high-performance potassium metal battery using safe ionic liquid electrolyte. Proceedings of the National Academy of Sciences of the United States of America Sun, H., Liang, P., Zhu, G., Hung, W. H., Li, Y., Tai, H., Huang, C., Li, J., Meng, Y., Angell, M., Wang, C., Dai, H. 2020


    Potassium secondary batteries are contenders of next-generation energy storage devices owing to the much higher abundance of potassium than lithium. However, safety issues and poor cycle life of K metal battery have been key bottlenecks. Here we report an ionic liquid electrolyte comprising 1-ethyl-3-methylimidazolium chloride/AlCl3/KCl/potassium bis(fluorosulfonyl) imide for safe and high-performance batteries. The electrolyte is nonflammable and exhibits a high ionic conductivity of 13.1 mS cm-1 at room temperature. A 3.6-V battery with K anode and Prussian blue/reduced graphene oxide cathode delivers a high energy and power density of 381 and 1,350 W kg-1, respectively. The battery shows an excellent cycling stability over 820 cycles, retaining 89% of the original capacity with high Coulombic efficiencies of 99.9%. High cyclability is also achieved at elevated temperatures up to 60 °C. Uniquely, robust K, Al, F, and Cl-containing passivating interphases are afforded with this electrolyte, which is key to superior battery cycling performances.

    View details for DOI 10.1073/pnas.2012716117

    View details for PubMedID 33106405