Where are official battery replacements even sold?

[Ondrashek06]

So Nintendo doesn't offer battery replacements for the DS(i) anymore. But I've always been wondering where exactly could I buy OFFICIAL NINTENDO replacement batteries, as stores like Amazon are filled to the brim with fake ones that look like they'll explode in a day of usage.

 

[FAST6191]

Be wary of official stuff as this point as there are three main options for such things, maybe four. I also have not checked to see if the same batteries or an effective replacement was used in a newer device as sometimes that happens.

1) Official stuff sold as replacement. Trouble being it will have sat in a box for however many years now and probably be into deep discharge. You might recover that but it is a not inconsiderable feat that you will likely want specialist gear for, if not some slightly specialist skills (though I imagine you could find a guide dealing with what stages to put constant current, constant voltages and monitor temperatures for as it will still be the same chemistry as a lot of other batteries -- just a different shape and maybe some kind of onboard controller).
There might have been a few official shops, or replacement part shops that ordered several from Nintendo's own replacement shop (quite possibly at this point the official way of doing it), back when and several of those did also appear to operate through Amazon, Ebay and other tat merchants as well as their own shops.

2) Official stuff sold as replacement but kept alive by some dealer with a clue. Good luck there as I have never seen such a thing outside of some very specialist equipment, much less for a failure of a console like the DSi.

3) Official stuff sold as something stripped for parts (buy cracked screen DSi, sell motherboard, buttons, shell, parts from board, battery... as separate for way more than cracked screen item cost). Massively variable as deep discharge and simple used for 5000 charges before now and thus half dead battery are possibilities here, almost as much of a gamble as third party stuff.

4) Ghost shift stuff. Basically Nintendo official but either done as a ghost shift (you have the tools and such all there, steal some materials or get the same in from the same factory and make your own) or failed QA for some hopefully minor reason.

Third party stuff can also be reasonable, especially if you don't just buy the cheapest thing out of Hong Kong. At the same time I would also be the first one to say it is often a gamble.