The main goals of this Work package can be summarized as follows:

Currently, Li-ion batteries are becoming the most widely used portable and rechargeable power source, with energy densities as high as 180 Wh kg–1. In the case of thin cells, their flexibility allows to store energy in volumes otherwise wasted with an increment of the energy/power density. The best choice for thin cells are nanostructured electrode materials, which can be synthesized by suitable wet routes leading to differently shaped particles (nanorods, nanowires, nanobelts, etc…). LiFePO4 is considered as the most suitable cathode material, due to its high electrochemical performance, low cost, high raw material availability and low environmental impact. An hydrothermal modified technique will be followed, for the synthesis, which allows to the formation of carbon coated high performing particles. Electrophoretic deposition will be pursued to get thin nanostructured cathode layers on the conductive substrate with controlled shape by means of inorganic template.

For what concerns the electrolyte, polymer membranes represent the high-end in terms of desirable properties as they are all-solid-state with a wide variety of shapes and sizes, light-weight and low fabrication cost. No corrosive or explosive liquid can leak out from a polymer electrolyte and internal short-circuit are less likely to happen, hence greater safety is guaranteed.

As anode, many metals which reversibly alloy with Li can be used, having very large specific capacity; unluckily, the insertion of Li+ ions during cycling is accompanied by enormous volume changes. This mechanical strain leads to the cracking of the electrodes and a loss of capacity to store charge. To limit this associated strain, nanostructured thin films and/or nanostructures of different systems, such as metallic alloys (Sn-Ni, Sn-Ni-Cu) and, in particular, Si, will be deposited by short and ultra short PLD technique.
Furthermore, both inkjet printing and UV curing will be adopted for the preparation of solid polymer metacrylic-based electrolytes which can readily form flexible 3D networks directly adherent to the nanostructured electrodes, allowing to withstand the large volume changes and bringing to the realization of low cost flexible cells.

In parallel, the same technology developed for the battery electrodes will be used for an important byproduct, known as supercapacitor, whose energy density lower than that of batteries (15 Wh/kg) is compensated by a superior power delivery or uptake (10 kW/kg), thus attracting research and industrial interests for the next generation of automotive electrical power source / backup. Basically, carbon based nanoporous high surface area electrodes (aligned carbon nanotubes or activated nanographite flakes) are coupled with solid electrolytes or pseudo capacitive materials (transition metal oxides) to give outstanding volumetric capacitances close to 100 F cm–3.