Technically, it can be done, but’s a not a job for the faint hearted.
Lipos do fail, its not uncommon, the electrolytes start to breakdown which causes the battery to swell. The DJI MP1 battery is also glued shut, so even if you manage to swap out the cells, the likelyhood of keeping the battery case in one piece is slim.
There are cheap third party DJI MP batteries on ebay for £70. It’s worth mentioning that these same ones are available on Aliexpress (a site I use regularly) for about £40. There are also some on Amazon too for £97, these too are from China.