What is the best way to buy a battery for my 3T?
dont buy online or from other sources better repair it from OnePlus service center
By sending your device into an authorized OnePlus Service Centre and have the battery replaced.
That will be a problem because I'm from Bosnia. I know how to replace the battery, I'm just interested in the best way to buy it.
Unfortunately you cannot buy an OEM battery via 3rd party retailers. OnePlus doesn't sell parts for it's devices. Only way of getting an OEM battery is by sending it in and have it replaced through an authorized OnePlus Service Center.
You can try aftermarket, though they are usually riddled with problems, such as "low temp" errors among other issues.
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