So I'm reading the “Battery Replacement Installation Manual” for the battery I just bought [1] and as translated instructions go, it's not that bad. But there are some choice bits though …
## Why does the phone echo?
The echo of the phone may be due to the installation problem. Can you see if there are any loose parts, because the battery will not affect the quality of the phone's call unless there is no power and cause the phone shut down.
“The echo of the phone?”
Feedback? Hearing my own voice echoed back to me? Maybe?
Anyway, carrying on …
## Why did I receive a swollen battery?
Because this kind of battery is encrypted …
I have no clue here. It states that swelling may occur if the temperature exceeds 158°F (70°C), and enter sleep mode if the temperature is too low, although it doesn't state what “too low” means. Fortunately, the battery I received isn't swollen, so I guess it's not encrypted?
4. Please carefully check whether there is any debris or screws falling into the battery area. If there is, please clean it up before proceeding to the next step, otherwise the sundries may pierce the battery and cause a short circuit and cause spontaneous combustion.
“Sundries.” Love it!