For those that complain all the time about the lack of LARGE LITHIUM batteries in our phones in the US, this is for you !
There are rules in this country about how many watt hours and the capacity of the mAh limit that batteries can have to be transported from overseas into this country without them changing the classification to what is called dangerous goods. Dangerous goods significantly incur larger shipping fees to be brought into the US, and transported throughout the US.
In the US single cell lithium batteries are capped at just under 5200 mAh, and has to be under 20 Watt hours ( how much power a battery used in 1 hour) Samsung's 5000 mAh battery is rated at 19.85 Watt hours just a hair under the limit. All lithium batteries in cell phones have to be submitted to the FCC for testing for rating (publicly available, it's how leakers get their info on upcoming phone releases)
Write to your US rep to have the antiquated regulations revised for modern tech and improved safety of newer lithium batteries.
Please don't came back with, but, One+13 has a 6000 mAh battery, it doesn't it is dual cell . It has 2 3000 mAh batteries so it could be sold in the US and EU. The EU it is capped at 5600 mAh ( couldn't find info on Watt Hours) Edit: One Plus uses Silicon Carbon batteries!
BTW, Samsung's 5000 mAh has been rated for 2000 charging cycles before the battery health will reach 80%. Those new 6000 mAh batteries that TechTubers have been raving about, they have been rated for 1500 charging cycles before reaching 80 battery health due to faster charging rates.
Ps, another tidbit.
Before you ask then why doesn't Samsung just put a 5200 mAh battery in the Ultra. Good question, during the manufacturing of lithium ion batteries mAh can fluctuate between each battery produced, this is why in the battery section of about phone it will say typical, 5000 mAh, it could be as much as 150mAh higher or lower. Samsung has to insure that it doesn't go over 5200 mAh.
??? Also, why does your profile status display "Writer"? 
