I had this EP205 Bluetooth speaker from the brand Ematic from 2014 (bought for 10 USD). In 2024 I realized it doesn't work when it's unplugged so the battery must be bad. This is a guide on how to replace the battery.

It was a nice speaker. Used mini USB to charge and had a bunch of accessories like a car charger. It's still for sale on Amazon.

Looking at the reviews (mostly from 2016), it looks like everyone had the same issue (battery doesn't hold a charge). I did not have this issue back then, only after a decade when I found it in the electronics/cable box.

Speaker with accessories

Spoiler alert: The battery is actually easy to change without completely opening the speaker, but my battery was bloated and I could not get it out.

Bloated battery could not be removed

First, we remove the plastic flaps and then open the metal net. Unbend (?) these two parts to remove it.

Metal net

Now you have the speaker, open these screws.

Screws to open the speaker

Don't yank the parts off, open one side to see these two connectors that should be removed.

Connectors inside the speakers

Another look at those connectors

Now you can take the top part off

Some pictures from the inside:

Inside

More inside

And then finally the battery that could not be removed without lifting the PCB.

Removing the bloated battery

It's a BL-5C battery.

Bloated BL-5C battery

I bought one for 5 USD and then donated the speaker. Hopefully, it has found a new life.