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Silicon carbon void structures (Si-C) are attractive anode materials for Lithium-ion batteries to cope with the volume changes of silicon during cycling. In this study, Si-C with varying Si contents (28 ‑ 37 %) are evaluated in all-solid-state batteries (ASSBs) for the first time. The carbon matrix enables enhanced performance and lifetime of the Si-C composites compared to bare silicon nanoparticles in half-cells even at high loadings of up to 7.4 mAh cm-2. In full cells with nickel-rich NCM (LiNi0.9Co0.05Mn0.05O2, 210 mAh g-1), kinetic limitations in the anode lead to a lowered voltage plateau compared to NCM half-cells. The solid electrolyte (Li6PS5Cl, 3 mS cm-1) does not penetrate the Si-C void structure resulting in less side reactions and higher initial coulombic efficiency compared to a liquid electrolyte (72.7 % vs. 31.0 %). Investigating the influence of balancing of full cells using 3-electrode ASSB cells revealed a higher delithiation of the cathode as a result of the higher cut-off voltage of the anode at high n/p ratios. During galvanostatic cycling, full cells with either a low or rather high overbalancing of the anode showed the highest capacity retention of up to 87.7 % after 50 cycles.

Silicon anodes offer a very promising approach to boost the energy density of lithium-ion batteries. While silicon anodes show a high capacity and, depending on the system, a good cycle stability in half-cells vs lithium, their integration in industrially applicable lithium-ion full-cells is still challenging. Balancing described as the capacity ratio of negative and positive electrode (n/p ratio) is a crucial necessity for the successful design of lithium-ion batteries. In this work, three different silicon based anode systems, namely carbon coated silicon nanowires, columnar silicon thin films and silicon-carbon void structures are compared in LIB full cells containing NMC111 cathodes. By varying the areal capacity of the NMC111 cathode, the influence of the balancing was investigated over a broad n/p range of 0.8−3.2. The aim was to find an ideal compromise between lithium plating suppression, high cycling stability and maximized energy density. To underline the high volumetric energy density, the columnar silicon thin films are additionally analyzed in multilayered pouch cells with NMC622 and NMC811 cathodes resulting in 605 Wh L−1 and 135 Wh kg−1 and even 806 Wh L−1 and 183 Wh kg−1 as demonstrated on stack level.

In recent years, both silicon thin films and nickel-rich layered oxides have received much attention as promising anode or cathode materials for next generation lithium ion batteries, respectively. In this work, full cells containing Li[Ni0.8Co0.1Mn0.1]O-2 (NCM811) as cathode in combination with amorphous columnar silicon thin films as anode are evaluated in coin cells and 3-electrode cells with varying capacity balancing. Full cells with area capacity ratios of negative to positive electrodes (n/p-ratio) reaching from 1.15 : 1 to 2.70 : 1 are studied. The cells with a high n/p-ratio (2.00 : 1 and 2.70 : 1) show significantly lower specific capacity of 115 mA h g(NCM)(-1) after 50 cycles of galvanostatic cycling in comparison to 130 mA h gNCM-1 for a cell with a n/p-ratio of 1.15 : 1. One reason for this phenomenon is the decline of the initial coulombic efficiency with increasing n/p-ratios. Secondly, through only partial utilization of the silicon anode by using high n/p-ratios, the anode potential is increased at the end of charge. This leads to a higher cathode potential and therefore a faster degradation of the cell. In summary, for designing high performance NCM811/Si full cells, high n/p-ratios should be avoided.

Uromodulin (UMOD) mutations are responsible for three autosomal dominant tubulo-interstitial nephropathies including medullary cystic kidney disease type 2 (MCKD2), familial juvenile hyperuricemic nephropathy and glomerulocystic kidney disease. Symptoms include renal salt wasting, hyperuricemia, gout, hypertension and end-stage renal disease. MCKD is part of the 'nephronophthisis-MCKD complex', a group of cystic kidney diseases. Both disorders have an indistinguishable histology and renal cysts are observed in either. For most genes mutated in cystic kidney disease, their proteins are expressed in the primary cilia/basal body complex. We identified seven novel UMOD mutations and were interested if UMOD protein was expressed in the primary renal cilia of human renal biopsies and if mutant UMOD would show a different expression pattern compared with that seen in control individuals. We demonstrate that UMOD is expressed in the primary cilia of renal tubules, using immunofluorescent studies in human kidney biopsy samples. The number of UMOD-positive primary cilia in UMOD patients is significantly decreased when compared with control samples. Additional immunofluorescence studies confirm ciliary expression of UMOD in cell culture. Ciliary expression of UMOD is also confirmed by electron microscopy. UMOD localization at the mitotic spindle poles and colocalization with other ciliary proteins such as nephrocystin-1 and kinesin family member 3A is demonstrated. Our data add UMOD to the group of proteins expressed in primary cilia, where mutations of the gene lead to cystic kidney disease.