Like batteries on ebay shipped from china or Japan?
If you put an aftermarket battery in your phone that is not approved under the conditions of your warranty then essentially you void it. There are ways to get much better battery life out of your stock battery but if the battery you have is bad then you want to replace it with an approved battery.
I am buying two batteries from different sellers on E-bay and my old battery works better than one of the "High Capacity Battery" with 2450mah and the other one never works on my cellular and i am talking about when i did the installation i place the battery charger for a lot of time and my cellular never turns on the battery charging steps in the screen.
I personally would not, aftermarkets are a hit-or-miss for me.
You could try making a post here and see if they have batteries in stock, you would want to ensure that if there are no more HTC-made ones, that the Aftermarket has some type of insurance or guarantee that your phone will not become damaged due to failure. (As insane as it might sound, there are some aftermarket part outlets that have a guarantee that I have purchased before online and will replace a unit if their part causes a malfunction.)
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