Who is the best mobile battery manufacturer?

Panasonic is the leader in Lithium battery. LG Sony and Samsung also have large research departments.. But lag behind Panasonic in capacity and it also used by tesla in their cars. Just as an example the 18650 which is 1860mah which was the original capacity Li Ion battery used almost everywhere, they have 4400 mah in the same shape and size now. While most Chinese are under 1000mah..

Although not necessarily, I have over 20 year old Li ion batteries still in working condition made by LG Sony etc.. But these were only charged to under 4.10 volts.. None of the batteries charged above that voltage to get higher capacity lasts even 5 years and usually go bad in 1 or 2 años. if 4.1v is 100% 4.2 gives like 120% and 4.4v gives over 30% etcétera. But the faster the battery will die over the 4.1 volts.. Capacity also drops faster for each recharge.. IE a battery charged to 4.3 volts will drop double the capacity each recharge than a battery that is only charged to 4.2 volts. So except capacity to drop much faster for batteries charged higher.

So as you can capacity is directly related to voltage and also directly related to capacity drop. I dont have any Panasonic batteries still working because they sell on capacity and hence charged to higher voltage but they dont expect you to use the device more than a couple of years max anyway.

I do not like our disposable culture. That is a lot of waste. Waste that is dangerous. And no one disposes the waste properly.