Rechargeable lithium ion batteries (LIB) as state of the art devices are considered as one of the most promising technologies to meet the challenges for future questions of energy storage. Although such batteries have gained commercial success, there are still some limitations in order to realize high-power requirements, especially for electric vehicles and hybrid electric vehicles but also mobile electric devices and power tools.
Here, we present a new concept of high-power LIB electrodes combining nanostructured active materials with a binder-free 3D current collector based on vertically aligned carbon nanotubes (VACNT) on metal foils. The benefit of this special material combination is found in low internal resistances what is the key issue for realizing high-power devices. This is achieved by using synthesis methods which assure very effective electrical contacting of active material with VACNT as well as VACNT with metallic current collector. Therefore, an atmospheric pressure CVD process is used for the direct growth of VACNT on metal foils. Subsequently in-situ growth of anode (LTO, lithium titanium oxide) and cathode material (LMO, lithium manganese oxide) on VACNT by a scalable chemical solution deposition (CSD) is used. Relations between crystallization conditions of LTO/LMO and electrode performances are shown. As a result impressive rate capabilities in half cells against lithium, e.g. 110 mAh/g at 300C in case of LTO, as well as in full cell setup for LTO against LMO up to 60C are achieved.
Consequently, the unique nanocomposite structure with its superior electrical conductivity make decorated VACNT a promising material for High-Power Li-Ion batteries.
Finally we present a process concept for Roll-to-Roll electrode fabrication to bridge the gap between lab-scale material development and industrially relevant processes.
 A. S. Arico, P. Bruce, B. Scrosati, J. M. Tarascon, W. V. Schalkwijk, Nat. Mater.2005, 4, 366.
 J. Maier, Nat. Mater.2005, 4, 805
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