This is a good point. All batteries are not created equal, and this applies to lithium 123A cells as well as others.

For the best reference regarding 123A *performance*, see the thread, 123 Battery Shoot Out on CPF. This is the most complete and definitive information on 123A battery performance I've seen.

In regards to safety, this is a serious concern with lithium technology. People should keep in mind that in addition to a failure of the battery, they can explode violently and they vent very dangerous fumes.

While talking about rechargeable lithium technology, the thread Li-Ion protection technology and possible dangers is a good read to get familiar with the dangers of lithium technology. I'd suggest it for anyone using any type of lithium batteries.

Note there are potential issues with manufacturing defects as Doug points out, and problems with people not understanding the risks well enough and doing things they shouldn't.

The first category is difficult to ascertain, but our best defense is as Doug suggests. Try to avoid "off-brands".

The latter is more under our control and basically comes down to: DO NOT mix and match cells of different brands or different charge levels! This means once cell lights are intrinsically more safe than multi cell lights.

Don't allow these batteries to be shorted!

Also, do not use UNprotected li-ion rechargables unless you know what you are doing!

Use of protected li-ion rechargables should still be done with care and understanding of the issues. Don't mix and match different charge levels, different brand/models, etc. Use a charger that does independent cell charging or only charge one cell at a time.

-john