Where do I get 18650? e scooter battery pack
Even the most respected manufacturers of 18650 cells (LG, Samsung, Sony, Panasonic, Sanyo) do not produce cells with such a high capacity. Their best cells are aroud 3500 mAh max.

So cells that are supposedly 9800 mAh tell me that these cells will be CRAP. I guarantee you that these will have far less usable capacity than 9800 mAh. You might be lucky if they can store 2000 mAh.

Besides that, dealing with Li-Ion based cells is not for the clueless. You need to have a good understanding of how to treat them. If you don't then don't tell you I did not warn you after your battery explodes/starts smoking/catches fire/lasts only 2 minutes.

One last point: why do you think e scooters / e-bikes / electric cars are expensive ? Let me tell you: it's the batteries. Good batteries are expensive. Don't waste your money on cheap brandless batteries with no guarantee that they work. Manufacturers (of e scooters etc.) know that so they buy quality batteries, they are worth it.