Help identifying a replacement battery


I am seeking help. I have a Steepletone phone ( that I need to source a replacement battery for. I can see it needs a Lithoum Ion battery

But I am really strugelling to find out the connector it needs to have. Much googleing has not resolved this. I enclose a photo:

It is quite hard to get a ruler into the battery enclosue - the one in the pic is at an angle and not flat -, but it is about 8.5 mm. What is the name of the 3 pin connector that I need to source a battery for?



Well, there are two questions; the physical connector and what they are supposed to be connected to. It could be a temperature sensor for the charge controller trying to avoid making the battery catch fire.

A random web search turns up a page that shows multiple similar JST-family and MOLEX-family connectors, some with NTC (negative temperature coefficient) temperature sensor pins, but which have multiple incompatible conventions for what pin connects to what…

It may help if you have a picture of the old battery with the connector, showing the wire colors, since it’s fairly common that black is negative, red is positive, and white is temperature sense for these.

It looks like the pin pitch is about 2mm; it seems too small to be 2.5mm or 2.54mm. So JST PH-3 is a possibility. It doesn’t look to me like Molex 51004/51065. JST PH does have an opening at one side like that.

But you’ll still need to figure out what wires go where.

Unfortunatly I do not have the origional battery. the unit was supplied without one. I have also tried to google for the manual, but no luck!

Also in side the phone as its a simple 2g phone will simply be the bones of a feature phone and the 3 pin connector is unlikley to be no different electrically than any other phone battery and most of mine have 3 connectors.


Well, there’s nothing on the surface that says what pin is what. If you want to open up the case and start to “buzz it out” to see what it’s connected to you can. I’ve done the best I can for helping identify the most likely connector, in any case. Good luck.

Might be helpful:
battery charging - Why are there 3 pins on some batteries? - Electrical Engineering Stack Exchange.

Check with these people and see if they were the ones who sold the phone and if they have a user manual with battery information:

Yes that is exactly what I did! And the outcome is a little more confsing. They say as follows:

The battery specifications are:

BL-5C 1020mAh
3.7v 3.8wh
Rechargeable Li-ion
It has 3 wires to a white plastic micro plug that will plug in inside the battery compartment of the telephone.

When I google the BL-5c it seem to me to be the trusty and ubiquitious “Nokia” battery present in phones of a generation ago but still used today e.g. in the classic Nokia 6100. However all the BL-5c batteries I can find on line are have flat contacts and no wires! I for sure could get a standard BL-5C and some how wire it to the connectors. They have supplied some photos of their battery they can supply, but unfortunatly not to my location in the EU as they are based in Great Britian! This is super frustrating. I attach the photos. So the issue now seems to be (1) can I source a BL-5C with wires and the appropriate connector and (2) what is the exat spec of the connector. The ones on batteries I have that look similiar, but, are much smaller. I have also now opened iup the phone and the dimention of the socket on the outside is amost exactly 10mm. I have asked them what the spec if but they have not given an answer. I am pursuing this, but, I am deaing with customer services and I suspect the members of this forum will be more expertise here and so will appreciate further help. At least this clears up what the middle connector does!

Photos from the company of their battery


Photos from the inside of the device. I was quite supprised to find tha tit was not simply a feature phone in a bigger case and has a bespoke board although it does seem to be based around a standard chip set.

I will post some more photos in a follow up as the system is limiting me to 5 photos.

Many thanks for any help.

More photos

So I think I hvae finally identified the connector as a JSP XHP 3. No amount of googeling finds a BL-5C with such a connector. Does anyone have any tips of soldering wires to the flat contacts of a standard BL-5c?

Use as little heat as possible.
Apply a little flux to the contacts if you have it.
Tin both the contacts and the connecting wire.
Solder the wire to the tab. Apply just enough heat for the solder to flow.

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