Naomi DIMM battery replacement

Frequently Asked Questions Technical Database
OldFoo

Post by OldFoo »

Hi!



My solution:



Image



Battery from Ebay:



http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 3D1&_rdc=1



HoP99
OldFoo

Post by OldFoo »

Nice houseofpain99 ordered some of those cells today
OldFoo

Post by OldFoo »

hi,



a tutorial in french for the french guy !!!!!!



http://www.ultimate-console.fr/=-Sega-n ... ard-=.html
OldFoo

Post by OldFoo »

I have been looking for a solution, thanks.
OldFoo

Post by OldFoo »

Hi,



Has anyone tried these as an alternative to the panasonic batteries.



2X Ultrafire 18650 3200mAh 3.7V Rechargeable Li-ion Battery



They're the same spec and about half the price of the panasonic ones.
OldFoo

Post by OldFoo »

Thanks for the great info. It was just enough that I did this myself today.



A few tips to add...



You can't "desolder" the tabs off of the original batteries on some of these as they are "spot welded" on. You can basically just grab them with some needlenose pliers and rip them off and then just use the pliers to flatten the pieces back, though, and they will work.



As for soldering battery packs, here's the deal. It helps to scuff the surface. I just hit them lightly with a bench grinder, but just about anything will work. Sandpaper, dremel tool, etc. You just need to get the surface well scuffed. Then apply some "soldering paste" or "flux". You can get this at places like Radio Shack, usually. Just a tiny film of it is all you need. Then make sure and use a high delivery iron or better yet, a soldering GUN. Pistol shaped, has a trigger.



Hold the trigger in the air until the tip will take some solder. Then put the tip on the batteries and add some solder in until it takes a film across the battery. Get this part done as quick as you reasonably can so as not to keep delivering a ton of heat into the battery.



Do this to both ends of all the cells. Then add some solder to the surfaces you ripped off the old cells. These do NOT need flux nor to be scuffed. They will take solder quite easily with just heat.



I found it easiest to use the plastic piece from between the original cells in the new pack you build and tape the two cells together. Then put them in a vice to hold for soldering. Then you just lay your tabs that you need to solder in place (you'll have two surfaces of solder touching) and hold with needlenose pliers. Apply heat with your gun to the top until it "squishes" together. Continue to hold, but remove the heat. Hold for a second, blow on it, and voila, you should have a good solder connection.



Then tape things back together.



Also, watch out for the fumes from this stuff. You don't want to be breathing it if you can help it.



If anyone knows where I can buy a couple of these packs that are "bad", I might be willing to repair a couple more and then sell replacement packs to folks who are willing to send me their bad ones.





--Donnie
OldFoo

Post by OldFoo »

Life is funny sometimes...



Turns out just a couple days after doing this mod, I found I had a dead battery in my Garmin 376C GPS unit. The GPS wouldn't recognize it was even there...it just said "Battery Missing" on the screen. It's a bit more of a "black box" than our DIMM batteries in that it's encased in a hunk of plastic, and in the past when this happened I just bought a new one.



This time I decided to hit the net and see if anyone had tried to fix these. Turns out, of course, they had. It also turns out that it can be even easier. Apparently if these are let to sit too long, they will go to 0V on the cells and you get this "Battery Missing" state where the GPS won't even try to charge it. In reality, you just need to charge the cells with something else even just a little bit first, and they MAY come back to life. Some may be damaged and need to be replaced anyway, but some may come back to life.



They are the same exact cells used in the Sega Naomi DIMM and MAY have the exact same charger on them already, too. They look VERY similar, anyway. But they are the same 18650 cells wired what appears to be the same way.



I'm not terribly interested in trying it since mine are now repaired, but I think you could buy this same Garmin pack, take it apart, and rewire it to use the same 3 pin connector from the DIMM and it'll probably work. You can buy these packs from places like this:



http://www.batteryship.com/htmlos/htmlo ... 4AodIHoAIA



You can see pictures of one taken apart and the process I'm talking about here:



http://forums.gps.org.nz/viewtopic.php?f=7&t=4131%28you



And I'm guessing someone a little more industrious than me could post exactly what 3 pin plug and pins to buy from Mouser or Digikey and you wouldn't even have to dismantle an existing pack if you didn't want to.



Hope this helps...if someone pops for the $26 to try this, let us know if it works!





--Donnie
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