Some of the issues the team is addressing are related to the way aluminum behaves over time. For example, as a TUM press release states, aluminum has a tendency to creep particularly at high pressure, meaning connectors would loosen over time. Even at lower temperatures, a paper by Austin Weber in Assembly Magazine explains that aluminum will flow when placed under constant pressure, so even if secured under twice the crimping pressure of copper, in time it will become loose as the metal flows from the pressure points.