@MaverickLan
Minor edits to correct some of the poor grammer.
Observations - not to be confused with HP policy or statements
The battery has to be removed both to prevent additional damage to the hardware and because, well, the situation is just not going to get better on its own.
The battery is not likely to actually burst and according to HP data, the situation is not actually dangerous. The swelling could, however, cause structural damage to the case, hinges, display, and possibly other components.
According to the data, it is safe in the sense that the battery, until it fails utterly (and it will do so), will not likely explode or leak. You may end up with a more severely "broken" computer if something else breaks due to the expansion of the battery casing.
Even if you elected to have the computer repaired, you cannot (at least in the USA) reasonably ship a computer in this condition, even if the shipment is headed to the repair depot.
Were it me, I'd get that battery out of that computer. As a general rule, I am not one to take apart notebooks - that's what contracts and repair centers are for in my world. Nonetheless, I would make an exception for this situation. Out. Now.
Remove the battery and replace it.
OR
If you want to do so - replace the computer.
"Fat" Battery / Bloated Battery / Swollen Battery
- If the battery is in a swollen or bloated condition, the battery must be removed from the computer and replaced.
- There are no other remedies, tests, or useful options.
HP EliteBook/ProBook/Zbook Workstations - Notebook PCs - Swelling or Deformation of Notebook Battery
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