Founded in 2010, QuantumScape has spent most of the last decade perfecting solid-state batteries. Its major advancement came about four years ago when it developed a ceramic separator to replace the polymer separator conventionally used in batteries.
According to its website, the ceramic separator allows the replacement of carbon or silicon anode with lithium metal, which is much more energy-dense and stores more charge in the same volume. This also allowed QuantumScape to make an anode-less battery since lithium from the battery makes the anode on the first charge.