Battery replacement general query

[glamracket]

HP Envy 13 ad-105ne

Hello all. 

I've spent the last few weeks looking through the boards here, browsing various replies to questions about battery replacements. 

From the replies I have gathered that Ebay is the best place to find a replacement battery, as the enormous varieties of models produced means HP almost never has any in stock in their online store. 

I've also guessed that there may be a number of batteries that are still compatible with a laptop model, but the way this is figured out is a mystery, and the support team here is usually replying with a specific solution to an individual's question.

What I would like to ask is how can an everyday user determine which batteries are compatible with their device? For example are all the batteries which are used in HP's ad-1xx line compatible with one another? 

Cheers in advance!

[pbroussard · Accepted solution]

Well you get your model number, look up the service manual, where it has a list of all the parts, find the battery part number and start a search. HP only orders a certain run of batteries for a particular model, once they are gone, you can't get one from HP. But the makers of the batteries will run off more and sell them to resellers where they keep the supply going. Then the same battery makers will run off in some cases, the same battery they made for HP and market it as a replacement battery. Also there are battery makers using lower quality parts offering replacement batteries and a pretty good discount compared to the OEM batteries. Those are the ones that people want to avoid.