I noticed one of my Fenix lights tonight got real hot when being charged with the USB-C laptop charger. Is there a danger in relying on these higher-current-draw chargers in lights, especially since the manufacturers don’t provide their own limited charging blocks anymore?
There are a lot of variables.
How many amps does that light claim to charge at?
How low was the battery voltage when you started charging and did you feel it at various time periods during the full charge cycle? How long did it take and how long into the charge cycle did it seem hot. Do you normally let the voltage get that low before you charge that cell in that light? If you’re not able to answer those questions then it’s hard to say of it really got hotter than normal.
You may need a magnifying glass. What does that power supply say it will put out for amps at 5 volts?
No, you can use any USB-C charger you want. The device and the charger talk to each other digitally and “agree” on a current, even when it’s a huge 100W+ USB-C charger for laptops.
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If the flashlight’s charging circuit is reasonably designed, which a Fenix should be, then it should be safe to plug into any USB power supply that is reasonably designed, which an Apple should be.
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Apple has always been very careful about their bricks, especially since they switched to using USB-C PD, where they carefully follow the standards to every detail. Unless it’s broken, it’s definitely not to blame.
If you happen to have an external charger that shows internal resistance of a battery maybe you can check whether that battery of yours have high IR; perhaps its the battery building heat.
happens to me last month while charging a 5 year old MJ1 18650 with Nitecore UMs2. When i surface check the battery after 20 minutes charging at 1amp, the cell gets hot, pull it out and cool it with a fan.
Now im draining that green guy with my nightstand flashlight.
Cheers 
Update: I put the light on a regular android charger and the heat wasn’t an issue. I don’t think any harm is being done with a mac charger. it was just trippy to see the heat produced with the increased voltage.
There’s probably no difference in voltage. While PD power supplies can provide more than 5V if the device requests it, very few flashlights will do that.
There’s not really such a thing as a “regular Android charger”, but I’m assuming you mean a 5V USB-A power supply. The maximum current it can supply will affect how fast the battery charges and how warm the flashlight gets, and should be marked on the power supply. The Macbook power supply can likely output up to 3A, and your “regular Android charger” probably does less.
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I often use a power supply that came with my Android phone 4 years ago. Kyocera. It has a type-c port and it’s capable of 3 amps at 5 volts. It is also capable of 9,15 and 20 volts. If the flashlight calls for one amp it puts out one amp. If the flashlight calls for 2 amps it puts out two amps. Actually I’ve seen as high as 2.1 amps for short periods on some convoy flashlights that claim to charge at 2 amps. That’s all at 5 volts. When Samsung and some other high-end phones still came with power supplies I’m sure they used very similar power supplies even 6 years ago.
If the light is capable of 2 amps and you supply 1.5 amps then yeah it’s not going to get as hot. Unless you’ve measured the temperature with an infrared thermometer you don’t know exactly how hot it got.
Some Samsung phones in recent years have allowed the user to control how fast it charges. You can use standard charging or fast charging or super fast charging. That’s up to 45 Watts with the proper power supply.
While the current iPhone 16 pro can charge at up to 40 Watts, 27 w for the regular 16. Previous iPhones could only do 20 or 27 Watts depending on model.
Most of the important things already mentioned in this topic, but just a tip if you want to have a bit more peace of mind for a few $:
It might be worth purchasing a (cheap) USB-C to USB-C, 2-way USB meter, like the 2 models showed below. I believe I’ve paid between 5 to 6 euro each for them on Aliexpress.
Regardless how accurate they are, they at least give you an idea in which voltage mode (5, 9, 12, 15, etc.) the device/flashlight is being charged and at (roughly) what amps and/or watts. That way you can more easily spot if a charger (or device) is acting weird. You can also compare numbers between different chargers to see in which way they behave different.
The only downside might be that it sometimes might be difficult to directly plug these meters into a flashlight, if the USB-C port is recessed, due to a rubber protection flap for example. The upside is that then you could also plug it directly into the charger and measure it that way, since both meters work in 2 directions.
I have put in a Wurkkos TS10 for scale in the first photo:
And a photo I took recently from the ‘Hidance’ one in action, used to register the total charging time of a device:
