Suddenly my Galaxy s20 stopped charging with the super fast wall module and cable. Tried different module and cable with no effect. Older Samsung charger with USBB-Cable charges at standard rate. Wireless charger works fine.
Got brief flash of a large red triangle on wireless charger.
Considering that when you fast charge ANY battery that it's charging is going to create a lot of heat, and it's going to make the lithium battery expand faster which is going to wear it down faster as well. Due to s20 being an older model, The battery is going to struggle to take in all of that charge all at once so quickly. Fast charge cables are like using a waterfall to fill a shot glass. As where normal charge cables Are like using a sink to fill a cup. Either way, if you go too fast, it's gonna get messy.... Batteries expand as they are charged, And if charged too much or too quickly or both, then your battery could quite possibly explode. This is why newer models have a shut off where they will not allow any more charge to be taken in once it reaches 100%
Generic information about over heating is accurate. My problem turns out to be a damaged charging port daughter board, and the red triangle display indicated overheating during Wireless charging. I was using a third-party wireless charger, which may not fully cooperate with the Samsung devices (the watch seems to get stuck at 92% randomly).
Repair of the phone is possible, but given it's age and likely stress of the battery, I will replace with S 25 and get a Samsung multi-device wireless charger.
