Nokia Battery pinout

Yes, your multimeter leads.

OK Let's label the pinouts as ABCD. The battery is fully charged. So I measure just over 4V between A and D. Between A and C I measure just under

As the battery is very popular I would assume that someone out there has already done the hard work for me. That's why I ask whether anyone has come across a website with the internal details.

Forget the battery, why not check the charger you already have.

"Heywood Jablome">

Bet the polarity is marked in the plastic nearby as well.

It will maybe read something like 50 ohms to 50 kohms.

........... Phil

Two outside ones are + and - (marked on the label side). The other two are for battery id (you can get BMC-3 which is NiMH in the same housing, it works with the same phones). I've read some details about middle terminals some months ago and don't remember very well. I think there is a resistor between middle terminals with different value for BLC-2 and BMC-3.

My own research - BLC-2 seems to have ~122 k resistor between the middle terminals and nothing else while BMC-3 has ~39 k resistor between middle terminals and a diode(?) between + and closest terminal - 0.37V one way one no current other way.

I'll try to dig out the original info.

Tom

he'd be better off with the ni-mh battery in my opinion, lithium batteries are very picky about how they are charged and likely to go bang in a bad way if handled wrong, however, you could use an old 3310 or equiv' to hold and charge the battery and just tap from it with some wire.

highly recommend using the ni-mh version if you are going to charge with simple stuff.

charging

hack" I

Thanks Tom. I'll investigate that and see what resistance I get. What I am also interested in is the charge rate, maximum allowed discharge rate and other specs, so if there is a reasonably reputable web site with these figures, that would be nice.

I am quite aware of the dangers of incorrectly charging/discharging lithium batteries. The charge circuit that I plan to build within my device will be microprocessor controlled with fail safes. Unfortunately the space requirement does not allow for a mobile phone to be inside the enclosure.

Pull the battery apart. If you don't want to destroy your ask a phone shop if they have any dead ones.

You're probably better off researching lithium ion chargers - I understand their charging regime is different to NiMH and NiCad, and I'm fairly sure that with the correct circuit you can charge them properly using only the + and - terminals, so you don't really need to know what the other connections are for.

That would be the phone wouldn't it? :-)

correct

correct

The 2 center terminals 'should' be a temp sensor for use with a delta time/delta temp charging system. Easy way to tell is if it changes when it's warmed up in the hands or cooled in the fridge.

I know temperature change is often used for detecting end of charge for NiCads, but is it also used for LiIon?

"Poxy"

Convert the energy into mass - maybe ???

......... Phil

You are right - the energy has to go somewhere - obviously in increasing mass... But in my admittedly limited experience with lithium polymer batteries, my charger doesn't use temperature sensing. I'm wondering whether temperature change is customarily used in consumer devices like mobile phones.

In my case, the charger tapers the charge current, which I assume means some kind of constant-voltage charge.

BTW

Batteries are CHEMICAL machines - not electronic components..

They are products of the CHEMICAL engineering industry.

Very bloody secretive.

Very bloody weird stuff.

Full of outrageous scams.

See my contributions to EA magazine re: the great DSE Ni-Cd fraud .

....... Phil

NO!

"budgie"

Eg

.......... Phil

connections

I have looked into charging lithiums. The general practice is to hold a constant current till the battery reaches 4.2V, then taper off the current and hold the voltage at 4.2V till the charge current is under 10% of what it initially started at. Then switch off. (no trickle charge)

It would still be nice tho to find a web page of someone who has already done something like this. I'm sure they have and I'm sure there is a web site that describes it but its a shame that these phones and batteries are so popular that every site I find using google is one that wants to sell me nokia accessories!!!

For the record I'd prefer not to open the battery so I would still like to know for sure what is connected to the other terminals and other specs. including charge current etc.