Tech CSI: What killed these devices?

Let's test your powers of observation. Can you see what killed these devices, and offer a possible explanation as to why?

I have a lot of broken tech. Most of it dies because of hard work or abuse. I have two gadgets on the bench of enlightenment this morning, and I thought I'd bring you along for the autopsy.

I have one charger and one power bank. The 100W USB-C port on the charger is dead, and the power bank comes on, but after a few seconds goes into a weird mode where it doesn't output power.

Check this out: OnlyKey: The ultimate security key for professionals

Here's a shot of the internals of the power bank. Can you see the problem?

What's wrong?

What's wrong?

The photos below show the issue in greater detail. Can you tell what happened, and suggest a reason why?

Here's a shot of the internals of the charger. Can you see the problem?

What's wrong?

What's wrong?

The photos below show the issue in greater detail. Can you tell what happened, and suggest a reason why?

Answers below!

Power bank

I opened one side of the power bank and couldn't see anything wrong. But when I popped the other cover off, I saw corrosion (what I call 'green crusties") on the circuit board. A clear sign of moisture getting into the power bank (I did leave this one outside hooked up to a GoPro a few months ago, and it did rain on it, but it's also been on travels with me far and wide, so theere's been plenty of opportunities for this one to get wet).

There's also significant corrosion on the batteries, again pointing to water ingress being the issue.

Charger

I noticed on the charger that there was some brown schmoo around the seams of the charger as I was taking it apart. That gave me my first clue. Once inside, I noticed more brown staining around the capacitors. Then I noticed that the end has popped off one of the capacitors. I can also see some black staining near a resistor, suggesting that this has popped, releasing the "Magic Smoke."

My diagnosis -- knowing the history of this charger -- is that the problem here was overheating. This charger has been on my desk working 24/7 for a long time now, sometimes buried under stuff, and one of its jobs has been powering my MacBook Pro.

Did you spot these issues?