Thin-film lithium and lithium-ion batteries

Abstract

Research over the last decade at Oak Ridge National Laboratory has led to the development of solid-state thin-film lithium and lithium-ion batteries. The batteries, which are less than 15 mm thick, have important applications in a variety of consumer and medical products, and they are useful research tools in characterizing the properties of lithium intercalation compounds in thin-film form. The batteries consist of cathodes that are crystalline or nanocrystalline oxide-based lithium intercalation compounds such as LiCoO and LiMn O , and anodes of lithium metal, inorganic compounds such as can deliver up to 30% of their maximum capacity between 4.2 and 3 V at discharge currents of 10 mA / cm , and at more moderate discharge-charge rates, the capacity decreases by negligible amounts over thousands of cycles. Thin films of crystalline lithium manganese oxide with the general composition Li Mn O exhibit on the initial charge significant 11x 22y 4 capacity at 5 V and, depending on the deposition process, at 4.6 V as well, as a consequence of the manganese deficiency-lithium excess. The 5-V plateau is believed to be due to oxidation Mn of ions to valence states higher than 1 4 accompanied by a rearrangement of the lattice. The gap between the discharge-charge curves of cells with as-deposited nanocrystalline Li Mn O cathodes is due to a true hysteresis as opposed to a kinetically hindered relaxation observed 11x 22y 4with the highly crystalline films. This behavior was confirmed by observing classic scanning curves on charge and discharge 1 at intermediate stages of insertion and extraction of Li ions. Extended cycling of lithium cells with these cathodes at 25 and 1008C leads to grain growth and evolution of the charge-discharge profiles toward those characteristic of well crystallized films.

Interfacial phenomena between lithium ion conductors and cathodes

“…Lithium ion batteries (LIBs) and related batteries are supposed to be one of promising energy storage devices [1][2][3][4][5][6]. LIBs used for those purpose would be much larger than conventional LIBs, and all solid state batteries that employ solid electrolytes (especially inorganic ceramics electrolytes) attract interests because of their advantages that are hardly achieved by conventional batteries with liquid organic electrolytes [7][8][9]. With solid electrolytes, reliability and safety of batteries are improved because they are nonflammable, which are very important for large-scale battery systems.…”

In situ methods for Li-ion battery research: A review of recent developments

“…The Debye length for this material, as calculated from the Gouy-Chapmann theory, only amounts to a few angstroms. It is furthermore remarkable that the obtained width of the space charge layer is of the same size of the entire electrolyte layer in conventional thin film batteries [58]. In a second paper using electron holography the anode side of the electrochemical cell has been investigated [59].…”

Fabrication of Si-based three-dimensional microbatteries: A review

“…For example, Figs. 6(a) and 6(b) [29,30] show thin-film all-solid-state LIBs with a 2D sandwich structure (-) Li/LiPON/Li 2 MnO 4 (+). In the microbattery, the overall footprint area and thickness are about 3 mm 2 and 15 mm, respectively.…”