It is a huge step up to use a Lithium cobalt Ion cell WITH a protection PCB, so that is a good step, but as these photo's show, there are still variations in the quality of the PCB & components used.
There are also some great threads that have been written on Li-Ions in general, such as this one started by Newbie.
The main concern that some of us are trying to (diplomatically) get across is to both learn about the proper use of Li-Ions (which you may already know about--but a surprising number of Li-Ion users do not), but also to appreciate the quality control/manufacturing issues with various brands.
When you get into cheap Chinese technology products, some of them are good and some are downright dangerous. Most of these Chinese companies are ripping off patented quality products, and reproducing them as cheaply as possible. Most have no international liability/reputation concerns, so they have little motivation to go the extra mile to ensure a basic standard is followed, or even that their products are safe.
Good examples of safety design issues are the cheap Chinese chargers that unlike the more expensive Hong Kong manufactured Pila IBC, do not terminate the charging at 4.2V, but many Li-Ion users have no idea what can go wrong with overcharging them, or even if a charger they are looking at does terminate properly. They focus instead on some irrelevant issue such as the charging rate, like that makes it a better charger for Li-Ions.
The next issue to examine is the DX link to your trustfire 18650 cells gives the detailed technical information of:
- High rate discharge, no "memory effect"well, what does that mean exactly? How high of a rate of discharge should one assume is safe with these cells over a sustained duration? What are the over-charge and discharge protections set at? How have their PCB & protection components been tested? Who tested and verified them? What type of quality does the underlying cell have? How reliable is their manufacturing process? Do they have any quality control? Do they give a rat's arse if anything goes wrong?
- Short circuit, over-charge and discharge protection
Since you are going to rely on the PCB protection circuit as your proper cell management strategy, don't you think it would be wise to find out the details and reputation of the components of the cells? This example from Norm was clearly his fault but it shows something that really happened from a supposedly "smart" charger....that wasn't really very smart or safety oriented. Another video of a forced laptop fire induced from intentional overcharging.
Will a Trustfire brand cell with unknown quality of protection PCB/components give adequate protection? If you are willing to gamble, it may turn out fine....but I want something that has a reputation and quality track record. Has AW's cells been 100% perfect? No. I returned a batch 1-2 years ago that had problems...and I got detailed feedback on how this manufacturing defect happened, and the improved QA afterwards from AW, since his repuation as a seller is at stake. You don't have that reassurance or reputation from Trustfire/Ultrafire/Random-Fire.
Sorry for this being a little bit "preaching," but I only began to learn about the detailed risks about Lithium Cobalt batteries just over a year ago...and I know these issues need to be stated freshly for new users who are not aware yet.