Megawatt charging speeds for electrified motorsports: from 5% to 85% (SOC) in just under 90 seconds

The hofer powertrain battery team developed a fully functional high-voltage battery using a market-leading BMS system and fast-charging CCS DC wallbox available on the market at the time. The initial proof of concept (POC) involved installing it in a racing kart and subjecting it to a series of complex tests under load and with real road resistance, which significantly exceeded expectations. By simulating various driving situations with the high-voltage charging system, it was possible to determine the battery’s and system’s functionalities as well as the overall performance within the powertrain system, where all measurements confirmed the groundbreaking charging curve. The hofer powertrain BlueFire battery demonstrated extremely high cycle stability. In less than 90 seconds, the battery could be recharged successfully from 5-85% S0C (State of Charge). The LTO cells used for this purpose have proven to be particularly suitable for applications that require fast charging and discharging with high charging currents and have opened new possibilities for the future.

During this initial pilot project in pre-development, it became apparent that the new battery is ideal for 24-hour endurance races that rely on extremely short charging times. In addition, it can be variably scaled to fit different applications.

In the meantime, initial discussions with interested parties and investors have started with excellent responses. The engineers are currently focusing on increasing the already very high energy density in the cells of the BlueFire battery considerably while at the same time reducing the weight of these cells.

"In endurance races, the ultimate aim is to shorten charging times during pit stops so that the sports cars return to the circuit in no time. Exactly that happens when the necessary charging energy is transferred to the BlueFire battery using the megawatt charging system and appropriate MCS connector systems. This integrated system makes purely electric endurance races, such as an LMDe race series, into a spectacular and emotional experience, comparable to the new LMDh race series today," says Gerold Sluka, a senior battery expert at hofer powertrain.