Iv like to test and know how much uptime can be achieved by different powerbank.

I purchased this powerbank case on ebay and then purchased the 18650 3.7v batteries separately.

I have built two powerbank with identical cases but different batteries. 

• Powerbank – $5.35
• Batteries 18650 9600mha – $24.80
• Batteries 18650 6000mha – $22.49

The results?

• Batteries 18650 9600mha – 23 Hours
• Batteries 18650 6000mha – 18 Hours

It should also be noted that the Raspberry Pi is online via wifi during the whole test while getting pinged every minute.