If it shows nothing on the screen and it just beeps, you're right thinking that it's a hardware issue. I am getting the beep sounds continuously. Lenovo - ThinkPad L450 14' Intel Core i5 2. proc/acpi/ibm/fan shall control both of them at the same time, and report data from the first fan. Just go to find and download “Lenovo PC Diagnostics” in APP Store with mobile phone.
You can click on the laptop computers for more information also. Click on the Show Details button, and in a moment it will refresh the settings and tell your the Bar-Code number of the battery. 80GHz with Turbo Boost, 8 Cores, 16MB Cache) 8th Generation Intel® Core™ i7-8750H Processor (2.