Al/O2 high power/high energy cells

The Al/O₂ system is a primary, mechanically rechargeable power source delivering high power at a cell voltage of 1 V. It is suited best for applications at constant load or with low load variations where it is easy to control the efficiency. A major advantage is that it can be used at this high rate over a long to very long time. Using oxygen as the comburent makes it possible to maintain steady power densities of 1 W/cm² even in a compact battery design without thermal runaways. The use of air may have supplementary advantages, when the volume is not critical. The current densities are reduced (⩾0.4 A/cm²) but the conditions on the whole are more moderate: lower temperature range, lower concentrations, and less corrosion problems at standby. The reaction products are harmless and have little pollution effects. Before use the system has to be activated, and a specific delay is required to reach the temperature allowing the maximum (nominal) power. In the activated condition the system may be stored for an unlimited time