motors for charger

[jasto]

how can you connect a phone battery to a motor to charge it bearing in mind that a phone battery has three terminals?
what is the purpose of the centre terminal in a phone battery?

 

[Diver300]

The centre terminal is often the thermistor.

There are strict rules about charging lithium batteries or they explode. You would be better to regulate the voltage to 5 V and feed that to the phone. The charging circuit in the phone will keep the battery happy.

 

[carbonzit]

[post made in error. sorry!]

 

[Reloadron]

OK Jasto this subject was pretty much well beat up in this thread you started but we can visit the subject a little more I guess.

First as to the 3 wires on the battery. Could be as mentioned for a thermistor to monitor internal battery temperatures during charge. Bad and ugly things can happen if a battery gets too hot during a charge. The battery could also be a "Smart Battery" and Google is your best friend as to what exactly a smart battery is. The third wire could be any number of things that really depend on the phone and the battery and how they are configured. Also as Diver 300 mentions, if cell phone batteries are incorrectly charged (like over voltage) really bad and ugly things can happen. Thus unless you really understand the actual battery, how it is configured and how it works trying strange charging methods may be pretty unwise. Got it?

Now as to the motor runs a generator that charges a battery to run the motor in a big happy circle I had that very same idea when I was about 10 years old. I didn't quite have an understanding of perpetual motion and the idea seemed good to me. Hell, it made perfect sense. I presented this wonderful idea to my father who actually was an electrical engineer. He told me it would not work but if I wanted to try it then build it. I used old 12 volt automotive generators. Before cars had alternators they had generators and if you powered a generator it ran like a motor only backwards.

That damn project amused me for the better part of the summer of 1960. My batteries kept going dead. Sure looked good on paper in the beginning. One day my father took my hand and placed it on my motor and asked what I felt? I said it was hot. The same was true of my generator. Thus began my understanding of loss! Dad always said, you can't get something for nothing and I guess 51 years later he is still right about that.

Your plan with this idea is not well thought out. You may want to consider using a few solar cells to safely charge a phone battery. That would be a good project.

Ron

 

[carbonzit]

Your plan with this idea is not well thought out. You may want to consider using a few solar cells to safely charge a phone battery. That would be a good project.

Or a hand-cranked generator if you really like the idea of spinning things that generate electricity.

Heh; your little story reminds me of when my friend and I invented a really kewl thing--a continuously-variable gear setup for transmissions--until we realized that it was physically impossible. We were a little older than you were.

I think the OP stubbornly refuses to believe that perpetual motion is not possible. Hell, the friction losses alone from two motors, as he proposes, would be tremendous!

 

[Vizier87]

wow. a lot of input there. In my experience, charging it directly from a 5V source (like a typical Nokia charger) is okay so long as you know the rating of the battery. The exploding part.... I'm not sure. I've been charging and recharging 'em myself (I think I've played with nearly 30 Li-ion batteries that way) and nothing serious happened, just some heating issues and they're just in one or two cases AFAIR.

Also, I've seen the PMM thread, and I'm afraid you just have to be happy with using a Wind turbine connected to the motor>>An inverter circuit>>to the battery terminals.

 

[Reloadron]

@ Vizier87

Hey guys, don't diss my page if it's not good enough 'coz I'm no scientist on this.

Hell no and I like your images. Really nice and informative web. Personally, I have never had a battery LiPo type explode. I did manage to have a large NiCad cell explode in my hand and am damn glad the ends blew off rather than the force on my hand. Damn, that stung and hurt!

Jasto, however, still seems to have a way to go on the learning curve and I just don't want to encourage things till he has a better handle on batteries, motors, generators and other entertaining things.

Ron

 

[Vizier87]

@ Vizier87
Hell no and I like your images. Really nice and informative web. Personally, I have never had a battery LiPo type explode. I did manage to have a large NiCad cell explode in my hand and am damn glad the ends blew off rather than the force on my hand. Damn, that stung and hurt!

Jasto, however, still seems to have a way to go on the learning curve and I just don't want to encourage things till he has a better handle on batteries, motors, generators and other entertaining things.

Ron

Haha.. I was too paranoid about criticism until I edited my post above. Sorry for that, but thanks for the kind remark.

Edit: Just for references anyway.