Is the capacity of large-capacity polymer lithium battery as large as possible?

In today's society, most of them use some lithium batteries as a power source. Due to their small size, light weight, and large capacity, they are loved by consumers. But have you really studied whether the lithium batteries that are often used are qualified? Is the storage capacity of large-capacity polymer lithium batteries as large as possible?
Different models and specifications, especially batteries of different sizes, the higher their storage capacity, the longer the use time. Let's put aside the factors of size and weight, large-capacity spare lithium battery naturally means that the higher the storage capacity, the better.
The same large-capacity backup lithium battery model has exactly the same nominal capacity (for example, 600mAh), but the specific measured initial storage capacity is different. For example, one is 660mAh and the other is 605mAh. So is 660mAh better than 605mAh?
In fact, many battery merchants on the market now sell 40A batteries as 80A batteries with a false mark of storage capacity in order to achieve financial benefits. They remind everyone to buy batteries from lithium battery manufacturers; the actual situation is likely to be batteries with higher storage capacity.
If you are afraid of the false standard of polymer lithium batteries, then let us look at the calculation method of polymer lithium-ion batteries:
For the rapid estimation of polymer battery capacity, the commonly used estimation formula is: storage capacity = thickness * width * length * K (K unit is mah/mm^3). In the range of K value (0.07~0.11), the K value depends on the storage capacity, the larger the storage capacity, the larger the K value, the smaller the storage capacity, the smaller the K value (it can be understood that the larger the volume, the larger the K value). In practice, the K value can be set to 0.1.
For example, 103450 (10mm thick, 34mm wide, 50mm long), calculated capacity=10*34*50*0.1=1700, actual capacity is about 1800mah;
For example, 603048 (thickness 6mm, width 30mm, length 48mm), calculated storage capacity = 6*30*48*0.1=864, the actual capacity can reach 900mah.