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

[Robert L Cochran]

Ooops, I keep forgetting to email the list. Sorry Joerg.

Bob

-------- Original Message --------
Subject:        Re: [avr-chat] Li-ion cell phone batteries
Date:   Sat, 29 Mar 2008 19:57:35 -0400
From:   Robert L Cochran <address@hidden>
To:     Joerg Wunsch <address@hidden>
References:     <address@hidden>
<address@hidden> <address@hidden>
<address@hidden>



It's very likely that your black and red wires are the battery poles,
> and the blue one goes to a thermistor (against black, the negative
> pole) that is used to monitor the battery temperature when charging
> inside the cell phone.  This is because the cell phone charger circuit
> wants to charge with the highest possible current (so the charging
> time gets as short as possible).  If you reduce your current to a safe
> value beforehand, you are not strictly required to also monitor the
> temperature.
>
>   
Okay, the connector looks like a really small 3-pin female JST
connector. I could cut the connector off the wires, and solder on a
two-pin female JST connector I happen to have -- if it is safe to solder
those wires, I mean...the heat from a soldering operation on the battery
wires won't explode the battery, will it? Assuming I can safely solder
the positive and negative wires to a larger-sized 2-pin female JST
connector, I can then connect the battery to my lipo charger using the
same bananna plug adapter I use for my 11.1v lipo batteries. I don't
have a datasheet for the battery -- my Google searches don't seem to
find a "Power Products" website. I can set it up for not more than 800
mAh and 1C charging. That charger is pretty smart and I think it will
suggest a charging voltage and current.

I can put everything in a 9 mm ammunition container I happen to have.

Does all this make sense...or should I just buy a battery from Sparkfun
which comes fully documented?

I do in fact have a bench supply. It's a BK Precision 1670A and right
now I have it set up for my lipo charger. I really love the lipo/li-ion
batteries because they give me the freedom to move around with my projects.

Thanks

Bob