18650 Lithium Ion Batteries. Which are the best?

[MavicFT1P]

im a ebay person myself.
I had a friend who works for them, and i dont want him
turned into a box

 

[Detritalgeo]

If you hook up your HG2's to one of these you will have full protection, a USB charge port and a steady 5V output (then add a boost converter module if you need more Voltage) You can even do a few cells in parallel and still have a reasonable charge time.

5V 1A Micro USB TP4056 DW01A 18650 Lithium Battery Charging Board Charger Module 732387202165 | eBay

P.s., if you look at the TP4056 datasheet, you can add thermal protection by connecting a few resistors and a thermistor.