Anyone know of a good usb battery pack?

[Big-O]

I need a link to a good usb battery pack that a company sells, not a kit because I do not want to blow up my psp,ipod,etc. I would like it if it supplied the same voltage as a standard usb port.

[dankicksass]

A link to a kit is not a technical question. How to build your own, on the other hand, is.

You should already be familiar with the parts used in this hack, how it works, and how easy it is to do.

how-to: ‘usb battery’ v2
Jason Striegel wrote:

thanks to everyone’s great feedback, i’ve now got a usb battery that’s much more efficient and capable of delivering more current to a portable device. like i promised, i put together a slick little case to finish this hack off right. read on for some tips on building your own.

quick improvement
as mentioned by several readers, you’ll want to use a 5 volt regulator ic instead of the resistor/zener-diode combo i discussed previously. you’ll be able to charge your device faster while it is running and it’s much more efficient, which will give your 9 volt a longer battery life.

the best part is that it’s easier and cheaper to do it this way. just grab an lm7805 from your local hacker store and wire it up. connect the positive battery terminal to the 7805 input pin, the positive usb pin to the 7805 output pin, and connect the negative battery terminal and the usb ground pin to the 7805 ground pin.

which is which? if you hold the 7805 with the text facing you and the pins downward, the pins from left to right are: input, ground, output. it looks like this:

for the female usb connector, look down into the end of the connector so that it is oriented like so:

pin 1 is the positive (5v) terminal (which goes to the output of the 7805) and pin 4 is ground (which goes to the 7805 ground pin).

Code: Select all

You can find a USB-A Female connector most commonly in a USB-PS2 mouse adapter, bundled with most USB mice.  Carefully cut away the green plastic to reveal a USB-A Female connector, a PS2 Male connector, wire, and glue.  The glue can be removed with your soldering iron or a knife.  Always be careful when using sharp or hot tools.

easiest way to test

several people were wondering how to tell if you are going to fry your device. here’s the easiest way to test when you are all done wiring:

1. cut a standard usb cable in half.
2. plug the male end into your usb battery.
3. connect the positive and negative ends of your multimeter to the red and black usb wires respectively.
4. if it reads something very close to 5v then you are wired correctly.

making a case

usb battery case 1

i chose to make my case out of polystyrene plastic. you can find this stuff in sheet form at most hobby stores. it’s the same kind of plastic used in your standard plastic model kit and the sheet form lends itself nicely to making flat sided objects… like a small case for a usb battery!

basically, you can just cut the sheet to the size you want with an x-acto knife. then, just glue them together carefully with standard issue model cement. the cement is a polystyrene solvent and it melts the connected peices of plastic together. when you are finished with the basic assembly, use a sheet of 400 grit sandpaper to smooth the sides down and bevel the edges.

room with a view

here you can see the case during construction. i want it to be small, so i sized it just large enough to accommodate the battery and usb connector.

regarding the usb connector. metal can be notoriosly hard to secure to plastic. model cement works best for styrene on styrene, but 2 part epoxy or super glue seem to do the best job for syrene on metal. try to affix the largest possible surface area. i glued small pieces of styrene to each of the 4 faces of the usb connector. you can then cement on more styrene to build up a larger surface area which can then be securely affixed to the front of the case.

sliding door

to close off the battery compartment, i made a pretty simple sliding door. it’s just two pieces of styrene with a third smaller piece sandwiched in between. this slides on rails which were made by cementing thin strips of styrene to the case.

where to go from here

i’m still sithout an ipod shuffle, but that about wraps it up for my usb battery. there’s no reason you need to stop here, though. you can make something very similar for the firewire interface for a normal ipod with two 9v batteries in series and an lm7812 12v regulator. you can use ‘found’ objects like the altoids tins for your case. if you really want to get exotic, you could use something like bondo (wear gloves) over a styrene frame to make something more custom or organic looking.

i’m looking forward to seeing what you folks come up with. get out there, do something cool, and send it in!
comments

[Big-O]

Uh, why are you being a smart ass on the forum? you know what I mean, I want a link to a usb battery pack THAT IS MASS PRODUCED BY A LARGE CORPORATION. NO ASSEMBLY REQUIRED.

[Skyone]

Uh, why are you being a smart ass on the forum? you know what I mean, I want a link to a usb battery pack THAT IS MASS PRODUCED BY A LARGE CORPORATION. NO ASSEMBLY REQUIRED.

Whether or not he's being a smart-ass, you're being a jack-ass. Smart up or shut up. He's right, it's not a technical answer if it's just a link to some random site.

[shmagoogin77]

search

[dankicksass]

Uh, why are you being a smart ass on the forum? you know what I mean, I want a link to a usb battery pack THAT IS MASS PRODUCED BY A LARGE CORPORATION. NO ASSEMBLY REQUIRED.

http://search.ebay.com/search/search.dl ... sb+battery

[Big-O]

Uh, why are you being a smart ass on the forum? you know what I mean, I want a link to a usb battery pack THAT IS MASS PRODUCED BY A LARGE CORPORATION. NO ASSEMBLY REQUIRED.

Whether or not he's being a smart-ass, you're being a jack-ass. Smart up or shut up. He's right, it's not a technical answer if it's just a link to some random site.

Looks like we've got another one too.

WHat I really ment was, I want a battery pack in production, I put that in my first and second posts. How about if anyone want's to help and not up thier post count, try posting with a little more sanity.

[Skyone]

...try posting with a little more sanity.

Heh, funny guy.

[Big-O]

[bicostp]

Standard USB ports output 5 volts at something like 500ma. Using a 9v battery and a 7805 will give you the right voltage. (if you don't believe me, build that thing and use a USB fan or light to test it. )

WHat I really ment was, I want a battery pack in production...

Then this doesn't belong here.

Moverizing...

[Skyone]

Standard USB ports output 5 volts at something like 500ma. Using a 9v battery and a 7805 will give you the right voltage. (if you don't believe me, build that thing and use a USB fan or light to test it. )

WHat I really ment was, I want a battery pack in production...

Then this doesn't belong here.

Moverizing...

I can't suugest that 7805 9v battery stuff, it's fried two of my iPods.

[loup]

I can't suugest that 7805 9v battery stuff, it's fried two of my iPods.

I would be inclined to think that you did something wrong then

[Skyone]

I can't suugest that 7805 9v battery stuff, it's fried two of my iPods.

I would be inclined to think that you did something wrong then

Uhm, no. The 7805 output 5.01v... is that too much?

[loup]

Unfortunately I don't have an iPod so I'm not sure on its specifics. Is it supposed to charge off of 5vdc? If so, and 5.01vdc is enough to kill it, that would mean that it only has less than a .2% tolerance, that seems unlikely. I would guess it probably has at least a 5% tolerance, that means it can accept up to 5.25 volts.

I suppose that this does beg the question, how good are those 7805s you're using?

I'm also having a hard time wrapping my mind around the fact that you killed 2 iPods doing this. One would think that after killing your first iPod you'd do one of two things, either not try it again (okay, judging by the kind of people we all are on this board this doesn't seem likely,) or you'd figure out what the flaw was in your original design and figure out how to fix it.

I would suggest to anyone trying this hack, measure the output of the device, make sure that the power and ground are actually on the right pins, and maybe try it on something cheap before you kill your $300 iPod

[gamemasterAS]

I can't suugest that 7805 9v battery stuff, it's fried two of my iPods.

JOEVENIX did it he has a pick of it charging a shuffle on his site.