I know this topic is half a year old, but this info may be important for anyone searching this.
I have the same situation with a Tailbat that is just a couple of days old. When USB-C is plugged in, the red light blinks less frequently (once every 2 mins) than with a working battery. The attached atom lite remains off, but works if I power it directly. I think I broke the battery after accidentally swapping the poles in the USB cable for charging. Is there any way to open and repair it?