HE3DA~R battery concept represents a unique technological platform based on threedimensional electrodes using lithium nano-materials (patented HE3DA~R technology). The basic unit of HE3DA accumulator represent graphite anode, ceramic separator and LiNi1/3Mn1/3Co1/3O2 cathode. The layered LiNi_(1/3)Mn_(1/3)Co_(1/3)O2 (NMC 111) is a promising cathode material and represents environmentally acceptable replacement of widely used LiCoO2(1). NMC 111 is isostructural to layered LiCoO2, its Co content is only 1/3 of that in LiCoO2 and exhibits impressive stability upon cycling, reasonable specific capacity (150 mAh/g) and good high rate capability. Due to relatively low Li~+ diffusion coefficients of the order of 10~(-10)- 10~(-15) cm~2 /s (2) NMC 111 material consisting of nanocrystals with well-developed structure represents the best candidate for stable and fast Li-ion battery. NMC 111 for the basic unit of 48 V accumulator - 4 V cell is prepared by optimized procedure producing stable material providing charge capacity of 141 mAh/g (cyclic voltammetry) and 144 and 135 mAh/g (galvanostatic chronopotentiometry) at 1 and 10C, respectively(3). Evaluation of 103 Wh battery module containing optimized cathode NMC 111 material proved its stability and availability of 89% theoretical charge capacity after 5 formatting cycles. Battery passed successfully Audi battery test. In all 10 cycles of 3x15 s 100 A discharge the value of battery potential after 3rd discharging pulse did not decrease below 2.4 V limit. The first prototype of 48 V accumulator consisting of 12 particular basic modules was completed and tested. It passed successfully both load test and Audi battery test. To decrease further the production expenses and to minimize the amount of toxic Co, 4 V HE3DA cells with Ni rich cathode material (NMC 622 and 532) were assembled and tested. However, in contrary to expectations, their charge capacity did not exceed the values of the cell with NMC 111. Although graphite is a cheap and frequently used anode material, its layered structure exhibiting volume expansion of ca 13% in a fully lithiated state(4) represents a safety issue for Liion batteries. In contrary, TiO2 polymorphs are known as environmentally friendly and safe anode materials. We tried to develop easily scalable preparation of TiO2 anatase and TiO2(B) with reasonable charge capacity and cycling stability. Electrochemical measurements of optimized products proved charging capacities of 170-220 mAh/g for both anatase and TiO2(B) with a capacity drop less than 3% after 50 cycles at 1C charging rate.
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