Tutorial: Build a Rechargeable Battery Pack

Tech Talk
1

Alright I have been modding electronics for many years, and building sticks for just as long. As with many others I got in on the Street Fighter 4 craze and was able to help pay for college.

Thank you all.

So I am going to start a few Tutorials in order to give back to the community.

Here is my Tutorial on how to wire up a charging circuit for those of you who need Battery packs for Wireless projects (for PS3 or Xbox360) Both systems use about a 3volt supply, so these work for both (I have tested)

Parts List:
REMEMBER THE PRICES LISTED ARE AVERAGE IF YOU INTEND TO ONLY BUY ONE OF EACH! GENERALLY YOU CAN GET A BAG OF 100 OF MOST OF THESE ITEMS FOR ONLY $4-$9 WHICH WOULD DRASTICALLY LOWER THE OVERALL COST.

**2x Rechargable AA Batteries **(NIMH works the best but Nicads also work, but Nicads suck :stuck_out_tongue: also remember the larger the MAH, the longer they will last!)
Price: $4.00

http://i186.photobucket.com/albums/x169/poisonfree10/nimhAA-2500400.jpg

3x lengths of wire (between 20-26 gauge should be fine)
Price: Free, cut some old mouse chord or something

1x Battery Harness (This holds your 2x AA cells)
Price: $0.85

http://i186.photobucket.com/albums/x169/poisonfree10/AAHArness.jpg

1x 3v LED (Shows when the charger is plugged in, You can also replace this with a 3v LED push button like I do on my joysticks over at WWW.GANGSTERGAMER.COM where I have the Charging light double as the Synch button)
Price: $0.10

http://i186.photobucket.com/albums/x169/poisonfree10/LED.jpg

**1x 10 ohm watt (or watt) resistor **[Color code: Brown/Black/Black/Gold(or silver)]
Price: $0.10

http://i186.photobucket.com/albums/x169/poisonfree10/10ohm.jpg

1x 1 kohm Watt (or watt) resistor [color code: Brown/Black/Red/Gold(or silver)]

http://i186.photobucket.com/albums/x169/poisonfree10/1kohm.jpg

1x 1N4001 Rectifier Diode (or any 1amp 50v diode)
Price: $0.10

http://i186.photobucket.com/albums/x169/poisonfree10/1N4001_50V_1Amp_Diode.gif

1x Panel Mount 3.5mm Female DC Power Jack
Price: $3.00)

http://i186.photobucket.com/albums/x169/poisonfree10/35mmDC.jpg

1x Charging Cable from an old Nokia Cellphone (USB-to-3.5mm Nokia cables are available at most dollar stores, or you could use your old nokia charger)
Price: $1.00

http://i186.photobucket.com/albums/x169/poisonfree10/USBCHARGECABLE.jpg

To wire it up it’s simple, Solder the + lead from the battery pack to the 10ohm resistor, then solder that resistor to the 1N4001 Diode (striped side,) from there connect to the + terminal (center pin) of your DC Charging port. at that junction (after the Diode) solder the 1k ohm resistor, then solder the 3v LED after that. That completes the + side of the circuit.

Now simply wire the - side of the LED (identifiable by looking for a flattened side of the LED) to the negative terminal of your DC charging port. then solder the - wire from your battery pack to that - terminal on the charging port as well, and you are done.

I usually wrap up the components in heat shrink tubing (remember to slide it on before you start soldering, but its no big deal if you forget, just de-solder one end and slide it over)

I recommend for the first charge to let the batteries charge for 6hrs, after that they can fully charge in only a couple hours.

Here is an image to help with the wiring, good luck!

http://i186.photobucket.com/albums/x169/poisonfree10/charge_curcuit.jpg

2

Awesome!!! Thank you for posting this. I had a quick question, is there anyway to make it indicate when a charge is complete?

3

Another option is if the battery pack is easily accessible, why not just remove the batteries from the pack and charge them in a seperate AA battery charger? This way you could just pop in other batteries that you have and won’t have any down time.

4

So the LED is to indicate how much battery power is left, am I assuming right?

If so, lol Gameboy.

5

The way its described above, the LED is used to indicate that the charging is operational. I don’t think the OP meant it to show battery level.

I’m pretty sure if you press the Xbox/PS3 home button, the system menu would show the batter level.

6

Can you keep playing while its charging?

7

Nice tutorial. This is good for X360 users wanting more power for LEDs and other stuff.

Just a note though, the PS3 controllers use a 3.7V battery pack (li-ion) so they cannot be replaced with nicad, nimh, AA or AAA (1.2-1.5V). They need to be replaced with li-ion batteries (1 cell is 3.7V). Best bet for upgrading the PS3 batteries is to use an 18650 cell but make sure it’s protected! An RCR123A would work also but probably have only marginally better capacity than the original pack unless you put 2 or more in parallel.

–edit–

I don’t see why not, you can do it with the 360 play and charge kit so probably this too.

BTW, one of the best batteries you can get are the Sanyo Eneloops. 2000mAh for the AAs I believe and low self discharge rates.

8

This is definitely something I’ve been interested in doing for a controller.

As crazed already pointed out, 3.7v Li-ions seem like they would be the best for this; they are what PS3 official controllers use, but tend to have a low capacity. But Mek says that he’s tested them (hopefully both the official wireless PCBs) and NIMHs work.

So some questions:
Can you just replace the PS3 battery with rechargeable batteries and have the USB plug/system charge it?
Do these batteries need added circuits for protection of the PCB or do the PCBs come with those circuits? If so, what do these circuits need to look like?
What about overcharging in the circuit Mek shows?
What about using a wall-socket phone charger instead of that USB kind?

9

Li-ions aren’t too bad capacity wise but you’re right, they are a bit less dense size/power wise compared to NiMH though. They’re pricey too. Either way, pretty much anything you get will be an upgrade from the stock sixaxis though as I believe it’s around 600mAh (coin cell pack it seems like, since it’s so thin).

http://www.batteryjunction.com/tenergy-37-6600-pcb.html
That’s what I plan on using :slight_smile:

You raise some interesting concerns however slagcoin. I guess the thing we need to know is how the charging circuitry works and when or how it determines to terminate the charge. I imagine it will charge but I don’t know if it would terminate the charge too early to fill the battery (or too late for AAs). Also, NiMH’s termination voltage is probably different. This is probably me overthinking but I won’t know until I try it.

I think overcharging ties in with the previous problem of how it determines when to terminate the charge, I would imagine this is all part of the controller PCB and not the battery since the battery appeared to have no PCB (it’s super thin). I’ll open the old pack when I get my new one and confirm that it’s working.

I don’t know about the protection, when I swap out the batteries I’ll let you know if the controllers fry or not :slight_smile: I would imagine that’s a part of the controller PCB as well, if there even is any. I wouldn’t imagine it necessary as long as the controller draws only the necessary current for what it needs. I don’t think that any function of the controller would create a direct short on the battery which would pass significant current through the controller. Unless the controller shorts out by accident or something.

Most of this is speculation of course, hence the I think and I guess. Hopefully I won’t have to wait long on my batteries to actually try it out.

For the wall socket, a powered USB port outputs 5V and I believe 500mA although I don’t think the current matters since it’s voltage regulated. So any wall socket phone charger that output 5V should be ok.

BTW I love your site slagcoin :slight_smile: It helped me a lot!

10

Some info:

-The LED is just to indicate that the charger is plugged in, it does not indicate the status of the charge.

-The 10 ohm resistor provides enough resistance to keep the temperature of the cells down during 12+ hour charging sessions. I would never recommend charging anything over an entire weekend. I monitored the temp with a Lazer thermometer for 10hrs and the temp never got over 80F (Generally damage happens at 125F+)

(I have a Nyko Charging station that melted, so just don’t leave batteries charging forever, even if they claim to have a charge detecting circuit)

-I have wired a 2xAA NIMH Pack directly to a Sixaxxis PCB and it ran fine, I did not test the life though. It did function fine with the pack. The LIPO 3.7 pack that the Sixxaxxis is supposed to run off of is an odd voltage, but it could be achieved with a Harness that uses 4 AA cells, bridge one cell space, and use 3 AA cells. I think I’ll try that ASAP I have some 4 AA harnesses lying around.

-Playing and charging works fine with XBOX controllers.

-I have dissected multiple Rechargeable packs in order to identify and test out the components. This simple setup is what most packs have in them with a direct charging port. The cells are easily removed from the harness so eventually when they do stop taking a good charge , you can swap them out with regular NIMH batteries without having to figure out the charging setup again.

-I have used this setup for other electronic projects and the cells have had no noticeable life issues in comparison to those I charged with a Regulated charging circuit.

11

It’d be nice to have 3 LEDs (say Red, Yellow and green) to achieve some basic charge status.

Maybe use some comparators to light up LEDs according to voltage supplied by charger. However, I have no idea what voltage corresponds to a completely flat battery, a half charged and fully charged, when a USB charger is connected. I was thinking about using some zener diodes to reduce the voltage available to status LEDs (higher zener with “more charged” status LEDs - erm, does that make sense ?).

Interesting thread as someone asked me to add this to his wireless stick mod.

12

Do you happen to have a pic of the wiring all done? It would be a great help for me personally :pleased:

13

alotta people were asking me how i did my re-charge circuit for my wireless stick. all the information can be found in this thread. very helpful. was wondering if we could get this stickied or maybe linked to in the “Everything you need to know about” thread.

good stuff here.

oh yeah, i can also confirm that if you’re batteries die and you plug it into the stick / wall, it will let you play while its charging. so basically it runs off wall power alone. very cool.

here’s a shot of my breadboard mockup:

and the guts (mind you, its a non-common ground, so alotta wires):

]

and side of stick w/ panel jack:

14

Do any electronics suppliers offer a better battery pack than what Radio Shack sells? I hate that you have to unscrew it to open it.

15

Dunno but this looks like a good deal.

http://www.thomas-distributing.com/maha_2700_rechargeable_batteries.php