Battery not detected

An extended battery for the Thinkpad x230 is not being detected and it isn’t charging either.
I have flashed the bios and done everything that the thinkpad community has discussed. The battery was discharging when I got it (so I know it works), but it wasn’t detected.
Now that the battery is dead, and it isn’t charging at all.

Any ideas?

Bios - 2.75 (with an ECmod)

Make sure the battery is connected securely. Then check output of:

inxi -B