This study presents the first laser porosificated silicon anode for lithium‐ion batteries. The pulsed laser induced pore creation improves the cycling stability of the d = 210 nm thick sputtered thin film anodes compared to plain Si. Galvanostatic cycling with a charge capacity limited to C = 932 mAh g−1 and a 2C current rate shows a stable cycling for more than N = 600 cycles. After N = 3000 cycles the laser porosificated and crystallized Si has a remaining capacity of C3000 > 120 mAh g−1. Postmortem scanning electron microscopy images after N = 3000 cycles prove that the laser porosification reduces cracks in the active layer.

The increasing need for high capacity batteries in plug-in hybrids and all-electric vehicles gives rise to the question of whether these batteries should be equipped with a few large capacity cells or rather many low capacity cells in parallel. This article demonstrates the possible benefits of smaller cells connected in parallel because of discharge effects. Measurements have been conducted proving the beneficial influence of a lower SoC on the thermal runaway behaviour of lithium-ion cells.A second test series examines the short circuit currents during an ongoing thermal propagation in parallel-connected cells. With the help of a developed equivalent circuit model and the results of the test series two major system parameters, the ohmic resistance of a cell during thermal runaway R tr and the resistance post thermal runaway R ptr are extracted for the test set-up. A further developed equivalent circuit model and its analytical description are presented and illustrate the great impact of R ptr on the overall discharged capacity. According to the model, cells with a capacity of no more than C cell = 10-15 Ah and a parallel-connection of 24 cells show the most potential to discharge a significant amount.