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The current Li-ion battery technology has reached its maturity and incremental improvements in energy density can not meet the ever increasing demand for more energy and power for portable electronic applications.Stabilized Lithium Metal Powder (SLMP TM ) is an enabling material and technology that creates opportunities for more choices of active materials to be used in Liion batteries resulting in systems with improved performance in energy, safety and possibly cost. In this work we have discussed the initial results for lithium powder stability in selected solvents. Material has been incorporated into Li-ion cells and resultsindicate that SLMP could be used as an independent source of lithium. Examples of using SLMP to improve the first cycle efficiency in silicon composite material and of Li-ion cell built with non-lithium providing cathode, such as the first Li-ion battery fabricated with a metal fluoride, BiF 3, are discussed. Approaches for synthesis of tin and silicon nanocomposites are presented.

The Li-ion capacitor (LIC) is composed of a lithium-doped carbon anode and an activated carbon cathode, which is a half Li-ion battery (LIB) and a half electrochemical double-layer capacitor (EDLC). LICs can achieve much more energy density than EDLC without sacrificing the high power performance advantage of capacitors over batteries. LIC pouch cells were assembled using activated carbon (AC) cathode and hard carbon (HC) + stabilized lithium metal power (SLMP ® ) anode. Different cathode configurations, various SLMP loadings on HC anode, and two types of separators were investigated to achieve the optimal electrochemical performance of the LIC. Firstly, the cathode binders study suggests that the PTFE binder offers improved energy and power performances for LIC in comparison to PVDF. Secondly, the mass ratio of SLMP to HC is at 1:7 to obtain the optimized electrochemical performance for LIC among all the various studied mass ratios between lithium loading amounts and active anode material. Finally, compared to the separator Celgard PP 3501, cellulose based TF40-30 is proven to be a preferred separator for LIC. IntroductionPeople are always pursuing more efficient energy storage devices which can provide high energy density, good power performance and long cycle life. The electrochemical double-layer capacitor (EDLC) contains two symmetrical activated carbon electrodes with high surface area and porous structure. Although the EDLC has the characteristics of high power and long cycle life, the energy density of an EDLC is less than 10% of that of a Li-ion battery (LIB), which restricts its application in the field of hybrid electric vehicles (HEVs), electric vehicles (EVs) and other large-scale energy storage systems. Therefore, in recent years considerable research has been focused on the development of a high energy density EDLC. Among all the energy storage systems that have been investigated and developed in the last few years, Li-ion Capacitors (LICs) have emerged to be one of the most promising because LICs achieve higher energy density than conventional EDLCs, and better power performance than LIBs as well being capable of long cycle life. LICs contain a pre-lithiated LIB anode electrode and an EDLC cathode electrode 1-3 . Extensive research has been done to optimize the electrochemical performance of the LICs 4-19 . Recently, Xu et al. 20 reported the effect of the electronic spatial extents (ESE) of ions for overpotential of Li-ion capacitors. Zhang et al. 21 studied

Lithium metal anode is regarded as the holy grail for the next generation battery materials due to its high theoretical specific capacity which is 10 times higher than that of graphite1. Currently, the most advanced lithium-ion battery cells have energy density of ~300 Wh/kg. Whereas, lithium metal batteries with liquid or semi solid electrolyte from Solidenergy2 and Sion Power3 have demonstrated record specific energy density of over 400 Wh/kg. Solid-state batteries use non-flammable solid electrolytes instead of liquid and, therefore, offer improved safety. The 20 Ah multi-layer all solid-state cells made by Solid Power have achieved 330 Wh/kg.4 However, solid state batteries can exceed the energy density of today's lithium-ion batteries only when the thin lithium metal foil (<20 um thickness) is used as anode enabling a pathway to beyond 400Wh/kg.Industrial scale thin Lithium metal foil is produced by hydraulic extrusion followed by a rolling process. This process usually requires a delicate balance between the pressure and tension created by both extruder and winder, so that the resulting foil is not torn or stretched, retaining all the dimensional characteristics required. This process can be extremely challenging when making lithium metal films with thickness less 20 µm due to the poor mechanical properties of lithium metal.5 Moreover, the cost of making these foils dramatically increases as the thickness decreases. Livent has recently developed Printable Lithium Technology (PLT), which incorporates stabilized lithium metal powder (SLMP®) into a stable printable formulation. This presentation will cover thin lithium foil manufacturing processes and highlight advantages and disadvantages of our approach. The electrochemical performance results will be presented.Figure 1A compares the 50 μm commercially available lithium foil (left) and 20 μm printed lithium foil (right) laminated to copper current collector. Figure 1A shows that a uniform film made from printable lithium formulation is consistent across the application area. Figure 1B and figure 1C are the optical microscope images of 50 μm commercially available lithium foil and 20 μm printed lithium foil, respectively. Figure 1B shows commercial foil made with conventional extrusion and rolling process has rough and scratched surface. Figure 1C shows that printed lithium foil preserves the shape of precursor particles and boundaries are formed creating higher surface area that potentially can mitigate dendrite growth by distributing current over a wider area. Figure 1D and 1E show the SEM and EDS images of the printed Lithium foil after lamination. Figure 1D and 1E show the clear presence of oxygen at the boundaries. Figure 1F shows the microscope image of printed lithium foil before calendering which is a monolayer. Figure 1G compares lithium plating and stripping properties of testing conducted in a symmetric pouch cell format with a current collector coated with 20 um printed lithium foil vs. 50 um commercially available lithium foil. Figure 1G shows ...