Those of you familiar with lithium ion rechargeable batteries may wonder how these new lithium AA batteries work given that common rechargeable lithium batteries have a nominal voltage of 3 volts or greater depending upon chemistry.

The rechargeable lithium cells are usually lithium manganese. Lithium iron disulfide cells are a nominal 1.5 volt cell. These are sold as a higher capacity replacement for alkaline batteries. These batteries are mostly primary cells (non-rechargeable) but there are some versions that are rechargeable, however I do not know if there are any in actual production.

There are experimental high temperature versions of lithium iron disulfide cells that are being used in electric vehicles. These might be workable for commercial vehicles that are always operating but to keep a battery at the required temperatures (around 350 centigrade) while idle would be wasteful and consumers aren’t going to wait for their car battery to warm up before they drive somewhere. There is at least one company that has a ambient temperature rechargeable lithium iron disulfide cell with patents pending.

I’ve seen numerous references on the web to secondary cells but I have yet to find anyone actually selling a rechargeable lithium iron disulfide cell. The potential advantage of such a cell, in terms of power to weight ratio, would be substantial.

I’ve tried to find information on the web on exactly what it is that makes this particular chemistry non-rechargeable and what it is that does make the rechargeable varieties rechargeable and I’ve found nothing. So if you happen to know, please leave a comment. Any good references would be appreciated.