How about polymer charging bank(1)

Is the carp ion charging bank good, or polymer hammer charging bank better? It really depends on your hobby. Hammer polymer battery is an upgrade product of hammer ion battery. Compared with the popular potassium ion battery, it has the advantages of large capacity, small size and safety. But it’s also more expensive, and in some ways the polymer potassium bank is better than the potassium ion bank
Polymer battery advantages

1.The operating voltage of a single battery is as high as 3.6v~3.8v, which is much higher than the 1.2V voltage of Ni-MH and Ni-spoke batteries
2. The capacity density is large, the capacity density is nickel metal hydride battery or nickel tin battery 1.5~2.5 times. Or higher
3. The self-discharge is small, and the capacity loss is small after being placed for a long time
4. Long life, normal use of its cycle life can reach more than 500 times
5.No memory effect, do not have to empty the remaining power before charging, easy to use
6. Good safety performance
The structure of the polymer potassium battery uses aluminum-plastic flexible packaging, which is different from the metal shell of the liquid cell. Once security risks occur, the liquid cell is prone to explosion, while the polymer cell will only inflate.