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Hierarchical porous carbon (HPC, DUT‐106) with tailored pore structure is synthesized using a versatile approach based on ZnO nanoparticles avoiding limitations present in conventional silica hard templating approaches. The benefit of the process presented here is the removal of all pore building components by pyrolysis of the ZnO/carbon composite without any need for either toxic/reactive gases or purification of the as‐prepared hierarchical porous carbon. The carbothermal reduction process is accompanied by an advantageous growing of distinctive micropores within the thin carbon walls. The resulting materials show not only high internal porosity (total pore volume up to 3.9 cm3 g−1) but also a large number of electrochemical reaction sites due to their remarkably high specific surface area (up to 3060 m2 g−1), which renders them particularly suitable for the application as sulfur host material. Applied in the lithium‐sulfur battery, the HPC/sulfur composite exhibits a capacity of >1200 mAh g−1‐sulfur (>750 mAh g−1 electrode) at a high sulfur loading of ≥ 3 mg cm−2 as well as outstanding rate capability. In fact, this impressive performance is achieved even using a low amount of electrolyte (6.8 μl mg−1 sulfur) allowing for further weight reduction and maintenance of high energy density on cell level.

The lithium sulfur battery system has been studied since the late 1970s and has seen renewed interest in recent years. However, even after three decades of intensive research, prolonged cycling can only be achieved when a large excess of electrolyte and lithium is used. Here, for the first time, a balanced and stable lithium sulfur full cell is demonstrated with silicon–carbon as well as all‐carbon anodes. More than 1000 cycles, a specific capacity up to 1470 mAh g−1 sulfur (720 mAh g−1 cathode), and a high coulombic efficiency of over 99% even with a low amount of electrolyte are achieved. The alternative anodes do not suffer from electrolyte depletion, which is found to be the main cause of cell failure when using metallic lithium anodes.

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A novel electrolyte approach for a lithium-sulfur secondary battery is presented, realistically portrayed on pouch cell level, with its decisive element being a new electrolyte system, a mixture of a hydrofluoro ether and sulfolane. The hereby suppressed polysulfide solubility enables high discharge capacities and requires only very low electrolyte excess (< 2.6 μL mg S −1 ) achieving high coulomb efficiencies above 94% (capacity retention of 77% over 40 cycles) without the necessity of adding lithium nitrate for shuttle suppression. Due to the low volatility, this adopted electrolyte concept promises significant benefits for large operational battery units.