How do you use modern rechargable battery packs on the Game Gear?

Hello everyone!

I was looking into getting the GG Powerback rechargeable battery pack for my Game Gear. I've heard that a lot of the battery packs in these have died or no longer hold charges as well as they use to.

My question is, can I replace the rechargeable battery pack in the powerback with a modern rechargeable battery pack? Yes, I know you can use rechargeable AA batteries but I rather have a device I can plug in permanently instead of swapping batteries.

Any help would be highly appreciated!

 

Are you trying to make it run off lithium ions and be able to plug in the entire unit like you would with say a cell phone for example? Also, how important is it that it be self contained? If that is important, how comfortable are you with modifying your game gear?

 

I'm perfectly fine with modifying my Game Gear.

I want to put the lithium ions inside the powerback attachment so I have room in the GG for OzOnE's upcoming HDMI mod board. After doing some research on the PowerBack, it apparently powers the GG via the ac adapter connector. Will a modern lithium ion supply 9V at 800mA?

 

Here is a video of someone putting lithium ions inside a powerback.

 

Thanks for the video. So how can I go about wiring these batteries in? I rather use a single battery or series of batteries that will match the 9V the GG is designed for. Is there a lithium ion out there that will give me the proper voltage and amps for the GG? Also, where can I get said battery?

 

I'm am a bit interested in this so I've been looking into it a little bit. As far as amps goes, the general consensus is that a stock GG draws about 300mA. This makes sense as it ran for about 2 hours on new Ni-Cds back in the day and they were generally rated at 600mAh.

As for the voltage, while the GG was powered on 9v, you'd have to see what the minimum it can be powered on is. In the video above, it seems to do ok at 7.4v. This is good as those flat cell Li-Ion packs generally only come in 3.7v. They make 9v singles that look like alkaline 9vs but they are generally low mAh. Other than that, they make 9v packs that are the older style (Round cells adhered together in a soft insulated covering) that are higher mAh, but bulky.

In the video above, he only has 1200 mAH packs. You are gonna wanna try and go higher than that in order to maximize battery life. Mind you, its not just a matter of wiring up two packs in series and stuffing them in there. Rechargeable batteries require extra circuitry in order to safely charge them. Failure to implement this can lead to explosions and fires. He shows that circuit above but doesn't go into detail.

If these can fit, http://www.adafruit.com/products/328 seem to be a good option as they are 2500mAh packs. You definitely are gonna have some homework to do with regards to the charging portion of this as it is important to get right. There is some information on the site I linked to about safely charging multiple packs at the same time, but their method involves a physical switch to change from charge mode to run mode, and I'm guessing you want to have it more like the video above where you can just charge while playing.

 

Some food for thought: Do the LED backlight mod. Huge amounts of power saved, right there.

That being said, I don't see why you couldn't swap in any kind of battery (that physically fit, obviously) in whatever power pack you fancy. As MC said, the problem is mostly with charging them, that's where the important differences are. So either recharge using an external charger, or expect to do some additional work integrating a battery-type-specific charging circuit (iirc recharging is the power board's task, so depending on space available you might need to replace that whole thing...).

 

Since the original charging circuit was designed for Ni-Cds, you would need to replace it with one that was designed for Li-Ions.

http://www.digikey.com/en/articles/techzone/2012/sep/a-designers-guide-to-lithium-battery-charging

This article goes over a lot of the things that need to be considered in designing or choosing one. Since doing it wrong involves the risk of fire, you might wanna go with external chargers unless you really know what you are doing. Although what you want to do seems like it should be an easy task, it's deceptively difficult to do correctly.

 

I have just taken my Charger Pack apart to try and bring it back to life, this is what I managed to find.


http://www.ebay.co.uk/itm/391172608222?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT

It is the exact same size and voltage as the original 6 cell battery they had in there. The MAH is higher but that means it will hold a longer charge.

I was looking at doing an internal battery mod with Li-Ions but with the additional circutry it takes up too much space to allow for any additional mods.

Once it turns up will let you know how it goes.

 

@PIXeL92

Two things with that plan.

1. The connector on the new set is much bigger than that of the old set, so you will have to replace that. The wire gauge on the new set appears to be noticeably lower than the stock pack so you'll have to do some soldering rather than cutting it off, crimping pins and fastening a new one on the end.
2. The original set is Ni-Cd while the new set is NiMH. They do have some different charging requirements, but since the powerback uses a trickle charger rather than a rapid charger, your risk is generally in making the batteries lose capacity before their time rather than fire and explosion. Although that CAN still happen if left plugged in way too long, it's very unlikely. Run a good stress test and keep checking the temperature to see how long it takes to get near a dangerous level, if at all.

Someone does exactly what you suggest in your post and it turns out ok for them. They even take the whole charging and temperature issue into account by showing measurements, although they don't seem to say how long the stress tested it for. All in all, it's a pretty good guide for what you are trying to do.

 

In regards to the connector I have got that sorted. Got a replacement cable and some shrink wrap.
I will be running some tests and noting down temps, run times and charge times for the first few days to see how well it works. I thought for £9 it was worth a gamble. I got the pack in a bundle of faulty GGs that I repair and then sell back on so it hasn't really cost me anything if it goes tits up.

Will keep you guys posted.

Cheers

 

Cool. For £9 that's definitely worth it. Can't wait to see the results.

 

What about using NiMH in place of NiCd?

I have a Game Gear battery pack (the external oval pack, not the flat one that screws on the back) and after having to wrangle with really weird screws (looks like inverted slot, the spanner bit I have barely works) tyhe old battery inside was 7.2v 1500 mAh and they are about the same size as many common "shotgun" packs but the connector is different. Also I've seen NiMH that seems to have better capacity and last longer without the risk of memory effect that NiCd suffers often.

 

That's exactly what @PIXeL92 is doing

 

My battery came yesterday, so I took the connector off of the old one and wired the new one up. However it still wasn't charging

So I probed the +ve and -ve of the DC jack and it was showing power, so going over the whole board it was as if no power was getting anywhere.

Any way it turned out the +ve trace had ever so slightly lifted off of the board so when testing it showed a connection but there wasn't a connection to the board.

With that all repaired it is working a treat. Outputing 7.32V lasts around 6 hours and charges fine it doesn't even get warm.

Before anyone asks I did try and remove the foam pads but then just fell apart in my hand, so I got some of my car body work tape and made some new foam stoppers.

 

Why not just put six ~2000mah AA batteries into the Game Gear itself?

 

Because one would need to remove those to recharge while external battery packs doesn't need to be removed?

Beside if one went NiMH route rather than NiCd, one can get over 5,000 in a Game Gear pack. The original Game Gear pack was 1300mAh

 

It was really in response to the people who are only using a 2000mah cells in their modded packs...

It would be very easy to modify the Game Gear to recharge its internal batteries, being nimh, they don't require a complex charger at all.

 

Nice job @PIXeL92 .

 

I didn't see your update to the post until now. That video was really helpful. They apparently were able to use the original power supply and the original board which is something that I would like to do! I think I'll follow that guide and see how it turns out. 4 hours is ok but is there a way to make it last longer. Will I need something like a 2.5A battery or is that too much?