Is replacing game save batteries BEFORE memory loss possible?

[Scooter]

I have a couple of old Genesis games with game saves still on them. The batteries have to wear out eventually and I'm actually quite impressed they are still working. I know that the act of removing the battery and replacing it with a new one would wipe the memory but surely there is a way to avoid this memory loss.

Why couldn't the old battery simply be left in place and a new battery installed on top of it? By wiring positive to positive and negative to negative the same 3V electrical input would be maintained and as the old battery wears out the new one will be there to maintain the electrical input. If my old ones have lasted 10+ years, surely a new one would continue to maintain the memory for about as long. It seems the only trick would be to insulate the new battery from making contact with other components on the board but a little electrical tape should do the trick. There is plenty of space inside the typical cart for a small extra battery so such an operation couldn't be too hard.

I'll admit that with a cart which has already lost its memory due to a bad battery removing the old and soldering or clipping in a new one in its place is the best solution but there just has to be a way to maintain existing memory if it's there through a little extra effort. I have a Sega CD RAM cart which has a few useless saves on it so I think I'll get a new battery and see what I can make happen. If the memory is lost there no harm done.

Can I get these lithium batteries at any Battery Patrol store or some similar store? Walgreen's carries a wide variety of button batteries but I don't know if they will have these batteries in a lithium version. I'm pretty sure the lithium nature of these batteries is why they last so long.

[Genesis Knight]

http://www.sega-16.com/feature_page.php?id=300&title=Tech%20Talk:%20Replacing%20Dead%20Cart%20Bat teries

Anyway, IIRC you can open the cart, plug it into the Genesis, and replace the battery while the power is on. I think Joe does this a lot or something; I remember him talking about it.

[TmEE]

I would replace the battery while its in MD too... putting a new battery on top of old one is not very good idea.

[Bratwurst]

Removing the battery from a cartridge while inserted in the game system is not a good idea. You run the risk of shorting circuits with electricity running through them and frying the game (or the system as well). To say nothing of the potential health hazard to yourself.

Most Genesis gameboards have two different sets of points for the battery, it's possible to connect a second battery with wires and remove the first, to keep a steady power source to the save ram.

Personally, I don't care about save games that much. Especially if you've already beaten a game, empty save slots just give you another excuse to play through it again.

Whenever I remove old batteries from my cartridges I install a coin cell holder so future replacements no longer require desoldering/resoldering. It's generally a good idea to eventually remove all batteries as they age because they could leak chemicals onto the circuit board, causing irreparable corrosive damage.

[megbydogs]

Can I get these lithium batteries at any Battery Patrol store or some similar store?

If you are planning on replacing the battery on multiple games, check out the link below. I've purchased from this site to replace lithium coin cells for my Dreamcast VMUs and car alarms and it amounts to a HUGE saving over retail stores. Hopefully, they carry the same kind used for Genesis games and your Sega CD RAM cart. Good luck.

http://www.wholesaleforeveryone.com/page/WFE/CTGY/batteries-watch-button-coin-lithium-sp