Re: [Fwd: Re: [avr-chat] Li-ion cell phone batteries]

[Blake Leverett]

On Sunday 30 March 2008, Joerg Wunsch wrote:
> I don't really understand why the danger of LiIon and LiPo cells is
> often exaggerated.  Yes, they can burn when being handled improperly.
> But about any kind of battery with enough stored energy in it is
> dangerous, in one way or another.  Your 44 Ah car battery is probably
> much more dangerous than an 800 mA LiIon cell.  It contains lead acid,
> and its stored energy can easily arrange for an explosion if you
> shortcut the battery e.g. by dropping a tool onto it that doesn't
> evaporize within a few hundred milliseconds.  Yet, nobody talks about
> banning lead acid batteries...

I don't think I was exaggerating the dangers.  And I do agree that LiIon 
batteries are safe in cellphones and laptops.  LiIon batteries are more 
dangerous than other types for two reasons - LiIon's are less forgiving of 
mishandling, and they are MUCH more flammable than other types.  Of course 
any battery can start a fire, but other batteries do not themselves burn so 
much.

So, the main message is to be careful - don't abuse LiIon batteries, and keep 
them in a fireproof container if there's any question about the battery.  
Remember the OP was talking about using a used battery from an unknown 
source.  Not every engineer knows about the special properties of these 
batteries, and learning by experience is costly.

Blake