Solved What is the best way to charge battery's?

[Manestricker]

I am referring to the circuit inside of the portable and how can you add a battery life indicator to tell if the battery is charged or dead?

SOLVED:

You don't have to remove the batteries to wire them, you wire a charging jack to your pcb, and connect it to the outside of the case.

Here's a diagram that shows you basically what you need to do: http://bitbuilt.net/forums/index.php?threads/charge-and-play.334/
When it's on, your batteries are powering your portable. When it's off, your charging jack is connected to your batteries, and you can charge them. If you don't care about being able to connect to wall power and play off that while charging your batteries, you can leave out that yellow power jack.

 

[bentomo]

What you're looking for is a battery management circuit. We don't know of any stand alone good ones but I'm designing one right now. As for the low battery indicator the cheapest solution is to measure the voltage under load with a resistor voltage divider and drive a transistor with that. However, that depends on the saturation voltage of the transistor, so you need a little trimmer potentiometer to adjust for the desired voltage.

 

[Manestricker]

What you're looking for is a battery management circuit. We don't know of any stand alone good ones but I'm designing one right now. As for the low battery indicator the cheapest solution is to measure the voltage under load with a resistor voltage divider and drive a transistor with that. However, that depends on the saturation voltage of the transistor, so you need a little trimmer potentiometer to adjust for the desired voltage.

So will I have to make my own circuit? Also if you could post circuits that you have used in the past that would be great.

 

[bentomo]

There are a few development boards out there that people have used directly in their portables. Right now most people use a switch and an external charger. The diagram is here on the forums. Hard to link on mobile

 

[Manestricker]

So are people currently removing their batteries and putting them back in or just charging them directly with no pcb involved?

Also here is a diagram of how I think this will work.

 

[JacksonS]

There must be a protection circuit between the batteries and the charger/load. That's just required so the batteries aren't overcharged or fully discharged, since that can be dangerous with lithium ion batteries. So anything connected to the batteries should go through a protection circuit.

 

[Luke]

You don't have to remove the batteries to wire them, you wire a charging jack to your pcb, and connect it to the outside of the case.

Here's a diagram that shows you basically what you need to do: http://bitbuilt.net/forums/index.php?threads/charge-and-play.334/
When it's on, your batteries are powering your portable. When it's off, your charging jack is connected to your batteries, and you can charge them. If you don't care about being able to connect to wall power and play off that while charging your batteries, you can leave out that yellow power jack.