Solid state battery charges in under five-minutes
Technology company Donut Lab has published the results of the first measurements analysing the features of its solid state battery, which verifies it can be charged from 0-80 per cent in less than five minutes.
The tests, conducted by Technology Research Centre VTT, evaluate the Donut Battery’s charging speed and thermal behaviour during charging.
It simulates a worst-case scenario, in which the battery cell lacks active temperature controls and its temperature can rise freely at extremely high charging rates.
The measurement was done using two passive cooling configurations: in the first, the cell was surrounded by two lightly compressed aluminium c¯ooling plates, and in the other the cell was attached to only one bottom cooling plate.
Recharging rates are indicated using C-rates, where 1C means that the battery is charged from empty to full in one hour (e.g. 5C = ~12 min, 11C = ~5-6 min).
Traditional lithium-ion batteries typically charge at 1C to 3C with active cooling, whereas in this measurement the charging power rises to significantly higher rates without active cooling.
The test started with a standard discharge capacity test at 1C, which was followed by rapid charging tests (at 5C and 11C) with both cooling configurations.
The measurements show that the Donut Battery can withstand astonishing charging rates even without active temperature control. Under the specified testing conditions, the cell was successfully charged at 5C for over nine minutes.
At this charging power, the battery cell reached an 80 per cent state-of-charge in about 9.5 minutes and a full 100 per cent state of charge in just over 12 minutes. When discharged after charging, 100 per cent of the charged capacity was available from the cell.
The battery cell was then recharged rapidly at the extreme speed of 11C.
Charging from 0 to 80 per cent was achieved in 4.5 minutes and a full 100 per cent state-of-charge in just over seven minutes. When discharged after a full charge, 98.4 to 99.6 per cent of the battery capacity was available for use.