Ann: $21.5 Million Non-Renounceable Rights Issue, page-154

Aluminum Is Interesting
Aluminum air batteries are particularly interesting for several reasons. The energy density (watt-hours per kilogram) is as much as five to ten times that of current production lithium ion cells. Aluminum metal for the anode is extremely light and, as the cathode is air, the overall package can be much lighter than most other battery types. Aluminum is also cheap—especially when compared to the rising costs of lithium. Aluminum air batteries have been used as experimental range extenders for electric vehicles, supplementing the built-in rechargeable batteries. They have also found limited uses in the military for aircraft and underwater vehicles, where their high power and light weight are of great benefit.

Unfortunately, aluminum air batteries also have some limitations. Thus far, the design has only been practical for non-rechargeable batteries. During the electrochemical reaction of the aluminum anode with the electrolyte, the aluminum is converted into a hydrated alumina that can no longer take part in the reaction. Work is underway to develop replaceable aluminum anode electrodes so that the battery can have more than one useful life.

Losing Their Mojo
Another problem with aluminum air batteries is how quickly they lose their charge. The batteries can be stored for long periods of time in their unused condition. Once they are switched on, however, they begin to degrade very quickly. Where a typical commercial lithium ion battery might lose about 5 percent of its charge after a month of storage, an aluminum air battery will lose about 80 percent of its charge over the same period, as the electrolyte reacts with the aluminum anode.

Several methods have been tried to reduce the corrosion reaction of the aluminum anode. Changes in the electrolyte formulation, for example, can reduce the degradation of the material, but also have been found to drastically reduce the power output of the battery. Others have tried pumping the electrolyte out of the cell when the battery is not in use, and pumping it back in when battery power is needed. This approach works, but aluminum corrosion products can often clog the plumbing system that pumps the electrolyte.

https://www.designnews.com/electronics-test/solution-aluminum-air-battery-issue/171999835659812

Gw