Lenovo dx show no issue with battery - ran all of the hardware diagnostics on their site. this has escalated recently - where periodically it would just shut itself off, even tho the battery had at least 20% - now it won't power on without charger and shows 98% battery. I've read some threads where this may be a windows 10 power setting issue?
Go into Control Panel by pressing the Windows key and R together then typing control into the Run box that shows up and hit the Enter key.
Select Device Manager and on top of the list is Batteries. Expand that and you'll see the Microsoft ACPI battery entry. Right click on that and select Disable and when you see the dour warning about death and destruction, ignore it and click Yes.
It may restart itself after a restart so keep going as long as you can and see if taking that utility out of the mix makes a difference.
How long have you had this laptop? Laptop batteries tend to go bad eventually, sometimes after only a year or two. Sounds like that's the problem and you need a replacement battery, but try what the other poster posted first.