This work demonstrates the feasibility of a novel solvent‐free anode production for lithium‐ion batteries. It combines a modified dry‐mixing procedure with an innovative electrostatic coating process. The mixing is divided into two steps. At first, carbon black and binder are deagglomerated and recombined to a matrix structure by intensive mixing. In a second less intensive step, this matrix is blended with graphite. The powder mixture is fluidized and then transferred to the current collector by inducing a high voltage. After a subsequent hot pressing step, the powder coating is permanently fixed on the current collector. This procedure is presented with three different fluorinated binders. Furthermore, effects of different mixing intensities on the powder and electrode properties are examined. The electrodes are investigated in the three‐electrode T‐cell setup versus lithium metal to examine their C‐rates and cycle stabilities. The produced anodes offer comparable electrochemical performance to conventional wet‐coated ones on electrode and cell levels. Overall, this new process is a suitable alternative to the conventional electrode production techniques.

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This work presents life cycle analysis, the primary energy demand and balance, as well as overall sustainability of using Pb-acid and Li-ion technology in residential photovoltaic systems. It is shown that the ecological amortization in residential storage occurs after only a few months of operation. The Li-ion storage system becomes environmentally positive after 0.6 years while Pb-acid systems require 1.8 years of operation before it becomes environmentally positive. Electricity generated by photovoltaics in residential systems is stored in battery systems with a typical capacity between 5 and 20 kWh. In this application Pb-acid and Li-ion batteries are the most common storage technologies. The environmental benefits of electricity storage generated by a 10 kWp PV-generator in combination with a 7.5 kWh battery is compared to the environmental costs of producing the storage system ( Fig. 1). In analyzing the environmental costs of producing a battery storage system, the energy usage in the following processes were compared for lithium-ion and lead-acid technology.r cell production r production of the battery system r transport to the customer This is then compared to the environmental benefits of the photovoltaic system, resulting in the minimum operation time needed for ecological amortization of the different battery technologies. MethodologyThe applied methodology was to investigate the real demand of primary energy for the production of 1 kWh storage capacity. For this reason, the energy demands of two battery production lines were analyzed. One line produces 1.4 million pieces Pb-acid SLI batteries per year with 12 V and 60 Ah energy content. The other line has the capability to produce 1.5 million Li-ion cells with 3.7 V nominal voltage and 20.5 Ah energy content per year.The data were obtained from real operating lines. 1 All the energy demands along production steps, starting from the raw materials to the final battery have been taken into account. The operating time of both lines was set to 280 days per year in 3 shift mode. Production scrap was taken into account with 5% for the Pb-acid line and 8% for the Li-ion line.Based on the total energy demand for one year of operation the primary energy demand for the production of one cell or battery, as well as the demand for producing 1 kWh storage capacity has been calculated for each battery technology. On the cell level the degrees of utilization (depth of discharge in recommended use) and lifetime during usage were taken into account (Table I).On system level the operation of both battery technologies in a photovoltaic home storage system is compared.Both cell typed are assembled to 7.5 kWh buffer systems and compared for an expected lifetime of 20 years of operation. The z E-mail: karl-heinz.pettinger@haw-landshut.de basic data used for the simulation are real measured PV-data and were obtained in Southern Germany (location Ruhstorf a. d. Rott) and standard load profiles for a typical 4-person household. 2Additionally a scenario for the transport has ...

This paper presents a comprehensive study of the influences of lamination at both electrode-separator interfaces of lithium-ion batteries consisting of LiNi1/3Mn1/3Co1/3O2 cathodes and graphite anodes. Typically, electrode-separator lamination shows a reduced capacity fade at fast-charging cycles. To study this behavior in detail, the anode and cathode were laminated separately to the separator and compared to the fully laminated and non-laminated state in single-cell format. The impedance of the cells was measured at different states of charge and during the cycling test up to 1500 fast-charging cycles. Lamination on the cathode interface clearly shows an initial decrease in the surface resistance with no correlation to aging effects along cycling, while lamination on both electrode-separator interfaces reduces the growth of the surface resistance along cycling. Lamination only on the anode-separator interface shows up to be sufficient to maintain the enhanced fast-charging capability for 1500 cycles, what we prove to arise from a significant reduction in growth of the solid electrolyte interface.

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