Hello,
I replaced the battery on my Lenovo X1 Extreme Gen2 with this one: [product|IF245-160-1] (iFixIt support confirmed that it's compatible with the Gen2). After installing the battery everything seemed to work: the power LED was orange and KDE indicated that the battery was at 72% and charging.
I worked for a while on my other laptop, and then noticed that the Lenovo was powered off. It will not power on at all now. I removed the battery but it's still dead.
Any ideas what the issue might be?