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So I've been given a neat task that includes rigging up a charger for a broken headset... I say broken because the point where the USB plug meets the mainboard is so badly damaged that I can not fix it. This is an 80$ wireless headset my younger brother has, luckily the battery is removable and has a standard looking plug.



I've done a small bit of digging for a charger that I can just plug this into, but frankly I'm not sure what the proper places are to look, so I come to you Gerbils for assistance. In case you can't see the tiny print, the battery is a 265mAh 3.7V 1Wh Li-ion Polymer Battery Pack. Solutions I've come up with are soldering some lose wires to an old AA battery charger and sticking them into the plug, and finding an actual charger that I can just plug this into. The latter is what I really want...

You need to be really careful about charging an Li battery, fire and explosions are possible!

The approach I'd take is to try and repair the damage and charge the battery in the headset with the supplied charger. If the board is really mangled I'd consider soldering a new USB socket on the end of a short flying lead and soldering the other end of the lead further back on the board. Of course given that this is a headset everything is going to be tiny so this may well not be an option.

I certainly wouldn't just connect that battery to an old AA charger! For a start AA rechargeable are only 1.2V cells so it wouldn't charge the 3.7V pack anyway but also because that white wire on the pack is probably a temperature sensor which will tell the charging to stop if the pack gets hot and you need a charger than can understand that! I'm sure ebay will have chargers that are designed for similar battery packs but the problem is that they have to be able to understand that particular pack. End of the day the warning about "only use the supplied charger" is on there for a reason.

Some photos of the damage would be nice (both sides of the board) even it's just for laughs.

Philldoe wrote:

I've done a small bit of digging for a charger that I can just plug this into, but frankly I'm not sure what the proper places are to look, so I come to you Gerbils for assistance. In case you can't see the tiny print, the battery is a 265mAh 3.7V 1Wh Li-ion Polymer Battery Pack. Solutions I've come up with are soldering some lose wires to an old AA battery charger and sticking them into the plug, and finding an actual charger that I can just plug this into. The latter is what I really want...

Please don't use a charger that is not made for LiPo cells. At best it will kill the battery. At worst. Something like this is what you are after: http://www.batteryspace.com/smartcharge ... isted.aspx. You might have to make an adapter for the plug though.

--SS

Suggestion from an engineer: Use a LiPo charger. If you have the DIY bug and have to try, there are charge controller ICs specifically for LiPo batteries. You must use the temperature sensor -- these batteries get hot during the last 10-15% of their charge cycle and the temperature sensor is there to regulate the charging. Some cheap chargers "guestimate" this and use a pre-defined charge rate based on experience learned through testing in a lab. If you're not careful they can go into destructive thermal run-away. It's going to be easier to use on off-the-shelf charger; but, it will cost a bit if you don't already have one. It might be easiest to fix the headset.

I would take it in to the local hobby store that specializes in RC cars/boats/planes. They should be able to point you in the right direction.