Originally Posted by Pokemon Trainer Sarah
The only problem is that the internal battery only lasts a certain amount of time, so all the Pokemon Gold/Silver's internal batteries would be dying sometime soon depending on how much they've been played.
There's a sticky thread that links you to a tutorial for replacing the battery here: http://www.pokemonelite2000.com/foru...ad.php?t=35844
Yes the internal battery does has a specific lifetime, but it only lasts within that amount of time provided it has been used, stored & charged under ideal conditions. These batteries which are used in Cartridges are Li-ion batteries (Lithium Ion). Lithium Ion batteries (not to be confused with single use Lithium) are incredibly light compared to other kinds of battery. Making them ideal for use in portable consumer devices. Lithium Ion has a high energy density which means for the overall physical size and weight they can store more energy than other types of rechargeable cell.
By default a Lithium Ion battery operates at a much higher voltage than other conventional technologies. This allows for more power from less cells and there for significantly impacts the design of a particular device. Typically a Lithium Ion cell operates at around 3.7 volts, where as a NiMH or NiCd cell can only provide 1.2 volts.
Lithium Ion cells like all batteries suffers from self discharge. With Li however it is significantly less than NiMH (Nickel Metal Hydride) or NiCd (Nickle Cadmium). Usually able to hold charge for several months with no active use. Lithium batteries can be stored for up to 10 years as long as they are given monthly top-up charges.
Another important point is that if a cartridge is not inserted in the GBC/GBA the Li-Ion battery inside is not charged, because of this its life span is reduced because if you leave the cartridge & its battery to fully discharge while in storage the circuitry which controls the inner workings of the battery will fuse and the battery will not be able to charge back-up. So when you wish to store a Li cell or your device for a prolonged period of time you should ensure that it is kept away from direct sunlight, in low humidity and as cold as possible (down to refrigerator temperature at most, never freeze them). 15 degrees Celsius is optimal. You should store the battery with a partial charge or around 40% but since this is impossible, don't worry about it. Furthermore, instead of meddling with cartridge's circuitry and going through the hassle of replacing the battery, I suggest that you simply buy a new one or maybe a second hand cartridge since new ones would most probably be out of stock by now.