DcMc's GCP!

[DcMc]

Hey guys,

I'm building my first portable!
I want to house it in a portable dvd player case with a 7 inch lcd (the player will be totally gutted and have no original parts inside it) and since alot of portable dvd players have detachable battery packs, I thought it would be perfect for a portable.
It will also have a wiikey fusion

Thoughts?

 

[Crazy Inventor]

Hey guys,

I'm building my first portable!
I want to house it in a portable dvd player case with a 7 inch lcd (the player will be totally gutted and have no original parts inside it) and since alot of portable dvd players have detachable battery packs, I thought it would be perfect for a portable.
It will also have a wiikey fusion

Thoughts?

It depends on if you plan on trimming the motherboard. The motherboard is fairly small in height but you'd still need a fan and possibly the original heat-sink. The idea is nice but unless you added height to the casing then it might be a tight fit. Good luck. Also I'm almost done with my portable and I can barely fit things in my case, so try to fit everything in it the way you want it aligned to see how it fits then move the parts around untill you get the configuration you want. And great idea with using the battery that came with it, gives you a spot for it. Again, Good Luck.

 

[DcMc]

So i've decided to ditch the portable DVD player idea.
I was wondering though, what would be the best way to use these (click here) batteries in a portable? Or am i way off base and should i use different ones? How many and how should i wire them?

 

[Tchay]

So i've decided to ditch the portable DVD player idea.
I was wondering though, what would be the best way to use these (click here) batteries in a portable? Or am i way off base and should i use different ones? How many and how should i wire them?

Those will work just fine. If you wire 2 of them in series, you will get 7.4v @ 4000mAh capacity. That will get you about 2 hours if I am not mistaken.

If you want more battery life and you have a lot of room in your case, buy 4 of them, wire 2 in series, the other 2 in series, then join both sets in parallel. If you are confused, stick with 2 batteries and/or find higher amp batteries.

 

[unicycler17]

If you buy those batteries, make sure that you buy ones with tabs, and solder to the tabs.

 

[DcMc]

So if i had 4 of them i would wire them like this:

 

[unicycler17]

Yes. Remember you will also need a pcb, and if you're only using 7.4v, you need to build a custom regulator

 

[DcMc]

What do you mean a pcb? what for?

 

[unicycler17]

A protection circuit board, so that your batteries wont explode.

 

[DcMc]

Can someone direct me to a thread that explains how to do this?

 

[Crazy Inventor]

Can someone direct me to a thread that explains how to do this?

Here try http://www.brighthub.com/engineering/electrical/articles/68396.aspx. IT gives information on how to build a PCB and even how to build low(and high) voltage indicators.

EDIT: Couldn't shorten it, it corrupted the url.

 

[DcMc]

I'm still confused

 

[Crazy Inventor]

I'm still confused

With what, how to make the PCB ,because I can't help, you there or with batteries in general?

 

[DcMc]

Just with the pcb and why i need it

 

[Crazy Inventor]

Just with the pcb and why i need it

Without a PCB I'm 99.99% sure that the battery will overcharge and too much overcharging could wear out the battery and possibly cause it to explode. Try these. They're the same battery that you were planning on using but with a PCB on it (sorted from lowest price to highest) and you get four for just about $20.

 

[Ashen]

Just with the pcb and why i need it

Without a PCB I'm 99.99% sure that the battery will overcharge and too much overcharging could wear out the battery and possibly cause it to explode. Try these. They're the same battery that you were planning on using but with a PCB on it (sorted from lowest price to highest) and you get four for just about $20.

There is no "possibly" about it. If you charge Lipo/Li-ion battery's without a protection PCB. THEY WILL EXPLODE.

Those e-bay batterys linked above are most likely garbage. These things have been gone over hundreds of times on these forums. All you'd have needed to do is read the sticky's in the voltage section. Still, this is most relevant to what you want and should get you started:

http://forums.benheck.com/viewtopic.php?f=43&t=34576

 

[XCVG]

Li-po/Li-ion batteries exploding without a PCB is not strictly true. RC hobby batteries generally do not use PCBs, as the current draw is too high and they would add extra weight (or maybe they are just cheap pricks). The thing is, the speed controller has undervoltage protection and the chargers used are special balancing chargers that continuously monitor the pack. Still, they sometimes swell or catch fire. In the portabilizing world, though, you want a PCB.

 

[DcMc]

Is it feasible to build a pcb? just one like the 2 battery one at benheck

 

[unicycler17]

Just buy one. They're less than ten bucks, and do you really want to risk blowing up your portable?

 

[DcMc]

Okay, I got polycase samples, and im gonna use 2 polycases put together. It's gonna be huge, but it will also have a TON of battery life. like 6 hours hopefully