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It depends on how you define "battery". I guess definition is different depending on if you are a chemist, an engineer or a consumer. When electrical engineers speak of batteries, they typically mean a _battery cell_ - a component. Then there's the end user application with a cell + electronics embedded in plastics with two metallic poles exposed. That is a more commonly called a _battery pack_.

If we look at classical alkaline batteries ("AA"/"AAA") which you have in various household equipment, they are actually bought from the local store as nothing but a battery cell. Shorting these won't be as spectacular since they have high internal resistance. They will get hot, but probably not to the point where they catch fire.

Li/ion battery cells often come in the very same mechanical shape. If you would short the poles of such a cell and enable a high current fast discharge, you may get thermal runaway causing a fire or explosion. There is nothing preventing this from happening except the resistance of the paper clip etc, which in case of raw copper won't be high at all.

It is not by any means mandatory that a Li/ion _cell_ has supervisory electronics built-in - this is an option. In case they have it, there will be a current sensing IC included in the mechanics. This seems more common than just having a fuse, because we still want high currents to pass during charging and then a fuse might be too blunt. The supervisory IC will measure current across a resistor, but it might also interract with a thermistor to also check the temperature. Having both makes for "redundancy" - two separate technologies that can be used as backup for each other, if one of them fails.

It is custom that battery chargers for higher currents also use a thermistor, not just to prevent overheating but to prevent charging in too low temperatures. The charger may either interact with the electronics attached to the cell, or in case there is none, place a NTC thermistor physically close to the surface of the batteries.

If more than one cell is used, the supervisory electronics is moved externally to a "BMS" (battery management system IC) which in addition to checking currents also balances the charge/discharge between the multiple cells. A supervisory BMS + multiple cells is what we call a battery pack.

Any combination of all of the above is possible. You can have no supervision, or supervision per cell, or supervision per pack.

Now in case of a battery pack for something like a drill like the one you link, it isn't really a "battery" but rather a whole electric system with a PCB. These need to be extra rugged because of the environment and also because it is expected to sit next to a mean little DC motor drawing all its current from it.

Now if you buy a copy of the Ryobi battery from a fishy site like Aliexpress, they will likely have cheaped out on some or all of this. The manufacturer might not even claim compliance with any particular standard or that the product is suitable for the market in the country where you live. Consumers are supposed to check for markings that verify such compliance: CE, FCC, UL etc. 

But all of that is still no guarantee. I stumbled across this [report](https://www.cpsc.gov/Recalls/2013/One-World-Technologies-Recalls-Ryobi-Cordless-Tool-Battery-Pack) regarding a 4Ah version of these very batteries, original Ryobi. There is _nothing_ a consumer could have done to know that these faulty ones were fire hazards. You'll notice it when it bursts into flames.

Older drills used NiMH or NiCd, which is much more safer and forgiving chemistries, but nowhere near the capacity of Li/ion. They didn't require supervisory circuits.